CN104834803A - Method and apparatus for calculating maximum permitted power of battery - Google Patents

Abstract

The present invention discloses a method and an apparatus for calculating a maximum permitted power of a battery. The method comprises the following steps: acquiring a polarized state of a battery when sampling for the kth times, and acquiring a polarized state parameter and a state of charge of the battery; according to the polarized state parameter when sampling for the kth times, calculating a polarized state parameter when sampling for the k+nth times; according to the state of charge and actual capacity of the battery when sampling for the kth times, calculating a state of charge of the battery when sampling for the k+nth times; and according to the polarized state parameter when sampling for the k+nth times and the state of charge of the battery when sampling for the k+nth times, calculating the maximum permitted power of the battery when sampling for the k+nth times. According to the method provided in the embodiments of the present invention, by increasing the polarized state of the battery to calculate the maximum permitted power of the battery, a calculation result is more accurate, a calculation error is reduced, calculation accuracy is improved and the service life of the battery is ensured.

Description

Battery maximum allowable power computing method and device

Technical field

The present invention relates to electric vehicle engineering field, particularly a kind of battery maximum allowable power computing method and device.

Background technology

Electric powered motor often has the restriction of maximum allowable power or electric current, and when normal use, the output of load (as drive motor) demand is in the scope that maximum allowable power limits, and battery can export any performance number.But, if the power that load request exports exceedes the scope of restriction, make the ceiling voltage of bus, minimum voltage, maximum current exceed the scope of permission, easily cause battery to produce irreversible deterioration, thus shorten the serviceable life of battery.

In correlation technique, battery management system usually adopts and in real time sends maximum available input-output power, thus restriction load (such as drive motor etc.) is taken from battery or feedback braking to the power in battery.But, when maximum allowable power being calculated in correlation technique, the polarized state of battery is not used as state variable, thus causes result of calculation to produce error, computational accuracy reduces, and easily makes battery there will be under-voltage (output) or overvoltage (input) fault.

Summary of the invention

The present invention is intended to solve one of technical matters in correlation technique at least to a certain extent.

For this reason, one object of the present invention is that proposing one can reduce the error of calculation, improves the battery maximum allowable power computing method of computational accuracy.

Another object of the present invention is to propose a kind of battery maximum allowable power calculation element.

For achieving the above object, one aspect of the present invention embodiment proposes a kind of battery maximum allowable power computing method, comprise the following steps: obtain the polarized state of battery during kth time sampling and obtain polarized state parameter and the state-of-charge of described battery, wherein, k is positive integer; Polarized state parameter when sampling according to described kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period; State-of-charge when sampling according to described kth time and the actual capacity of described battery calculate the state-of-charge of described battery when sampling for described kth+nT time; And the state-of-charge of described battery calculates the maximum allowable power of the described battery when described kth+nT sampling when sampling according to polarized state parameter during described kth+nT sampling and described kth+nT time.

According to the battery maximum allowable power computing method that the embodiment of the present invention proposes, during by obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of battery, to calculate polarized state parameter during kth+nT sampling according to polarized state parameter, and state-of-charge when calculating kth+nT sampling according to the actual capacity of state-of-charge and battery, thus the maximum allowable power of the battery when sampling for kth+nT time is calculated according to polarized state parameter during kth+nT sampling and state-of-charge, the maximum allowable power of polarized state to battery adding battery calculates, make the maximum allowable power that calculates more accurate, reduce the error of calculation, improve computational accuracy, ensure the serviceable life of battery.

In addition, battery maximum allowable power computing method according to the above embodiment of the present invention can also have following additional technical characteristic:

Further, in one embodiment of the invention, when the battery equivalent electrical circuit by having a RC circuit and the 2nd RC circuit obtains kth time sampling described battery polarized state and obtain polarized state parameter and the state-of-charge of described battery.

Further, in one embodiment of the invention, obtained the polarized state parameter of described battery by following formula, described formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance of a described RC circuit, R _lrepresent the second resistance of described 2nd RC circuit, C _srepresent the first electric capacity of a described RC circuit, C _lrepresent the second electric capacity of described 2nd RC circuit, U _srepresent the voltage of described first resistance, U _lrepresent the voltage of described second resistance, i _(k)the electric current of described battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance described in when sampling for kth+nT time, U _{l (k+nT)}represent the voltage of the second resistance described in when sampling for kth+nT time.

Further, in one embodiment of the invention, obtained the state-of-charge of described battery by energy accumulation approach, formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\η}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of described battery when representing that kth time is sampled, C represents the actual capacity of described battery, and η represents the coulombic efficiency of described battery, SOC _(k+nT)represent the state-of-charge of described battery during kth+nT sampling.

Further, in one embodiment of the invention, said method also comprises: the internal resistance obtaining described battery according to the temperature of described battery and state-of-charge.

The present invention on the other hand embodiment proposes a kind of battery maximum allowable power calculation element, it is characterized in that, comprising: the first acquisition module, during for obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of described battery, wherein, k is positive integer; State parameter computing module, polarized state parameter during for sampling according to described kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period; State-of-charge computing module, state-of-charge during for sampling according to described kth time and the actual capacity of described battery calculate the state-of-charge of described battery when sampling for described kth+nT time; And permission power computation module, during for sampling according to polarized state parameter during described kth+nT sampling and described kth+nT time, the state-of-charge of described battery calculates the maximum allowable power of the described battery when described kth+nT sampling.

According to the battery maximum allowable power calculation element that the embodiment of the present invention proposes, during by obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of battery, to calculate polarized state parameter during kth+nT sampling according to polarized state parameter, and state-of-charge when calculating kth+nT sampling according to the actual capacity of state-of-charge and battery, thus the maximum allowable power of the battery when sampling for kth+nT time is calculated according to polarized state parameter during kth+nT sampling and state-of-charge, the maximum allowable power of polarized state to battery adding battery calculates, make the maximum allowable power that calculates more accurate, reduce the error of calculation, improve computational accuracy, ensure the serviceable life of battery.

In addition, battery maximum allowable power calculation element according to the above embodiment of the present invention can also have following additional technical characteristic:

Further, in one embodiment of the invention, when described first acquisition module obtains kth time sampling by the battery equivalent electrical circuit with a RC circuit and the 2nd RC circuit described battery polarized state and obtain polarized state parameter and the state-of-charge of described battery.

Further, in one embodiment of the invention, described state parameter computing module obtains the polarized state parameter of described battery by following formula, and described formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance of a described RC circuit, R _lrepresent the second resistance of described 2nd RC circuit, C _srepresent the first electric capacity of a described RC circuit, C _lrepresent the second electric capacity of described 2nd RC circuit, U _srepresent the voltage of described first resistance, U _lrepresent the voltage of described second resistance, i _(k)the electric current of described battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance described in when sampling for kth+nT time, U _{l (k+nT)}represent the voltage of the second resistance described in when sampling for kth+nT time.

Further, in one embodiment of the invention, described state-of-charge computing module obtains the state-of-charge of described battery by energy accumulation approach, formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\η}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of described battery when representing that kth time is sampled, C represents the actual capacity of described battery, and η represents the coulombic efficiency of described battery, SOC _(k+nT)represent the state-of-charge of described battery during kth+nT sampling.

Further, in one embodiment of the invention, said apparatus also comprises: the second acquisition module, for obtaining the internal resistance of described battery according to the temperature of described battery and state-of-charge.

The aspect that the present invention adds and advantage will part provide in the following description, and part will become obvious from the following description, or be recognized by practice of the present invention.

Accompanying drawing explanation

The present invention above-mentioned and/or additional aspect and advantage will become obvious and easy understand from the following description of the accompanying drawings of embodiments, wherein:

Fig. 1 is the process flow diagram of battery maximum allowable power computing method according to an embodiment of the invention;

Fig. 2 is the circuit diagram of battery equivalent electrical circuit according to an embodiment of the invention;

Fig. 3 is the structural representation of battery maximum allowable power calculation element according to an embodiment of the invention; And

Fig. 4 is the structural representation of the battery maximum allowable power calculation element according to the present invention's specific embodiment.

Embodiment

Be described below in detail embodiments of the invention, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has element that is identical or similar functions from start to finish.Be exemplary below by the embodiment be described with reference to the drawings, be intended to for explaining the present invention, and can not limitation of the present invention be interpreted as.

In addition, term " first ", " second " only for describing object, and can not be interpreted as instruction or hint relative importance or imply the quantity indicating indicated technical characteristic.Thus, be limited with " first ", the feature of " second " can express or impliedly comprise one or more these features.In describing the invention, the implication of " multiple " is two or more, unless otherwise expressly limited specifically.

In the present invention, unless otherwise clearly defined and limited, the term such as term " installation ", " being connected ", " connection ", " fixing " should be interpreted broadly, and such as, can be fixedly connected with, also can be removably connect, or connect integratedly; Can be mechanical connection, also can be electrical connection; Can be directly be connected, also indirectly can be connected by intermediary, can be the connection of two element internals.For the ordinary skill in the art, above-mentioned term concrete meaning in the present invention can be understood as the case may be.

In the present invention, unless otherwise clearly defined and limited, fisrt feature second feature it " on " or D score can comprise the first and second features and directly contact, also can comprise the first and second features and not be directly contact but by the other characterisation contact between them.And, fisrt feature second feature " on ", " top " and " above " comprise fisrt feature directly over second feature and oblique upper, or only represent that fisrt feature level height is higher than second feature.Fisrt feature second feature " under ", " below " and " below " comprise fisrt feature directly over second feature and oblique upper, or only represent that fisrt feature level height is less than second feature.

Below before describing the battery maximum allowable power computing method and device proposed according to the embodiment of the present invention, the battery maximum allowable power computing technique in once correlation technique is simply described first.

In the related, the method of usual employing is by HPPC (Hybrid Pulse Power Characterization, combined power pulse characteristic) test show that battery is at different temperatures, different SOC (State Of Charge, state-of-charge) under maximum available output and output power and maximum allowable power, draw temperature (T)-state-of-charge (SOC) corresponding form such as table 1.Wherein, HPPC pulse specifically refers to adjust to the battery of different SOC and temperature after 1 hours rest, carry out charging and discharging 10s with the receptible maximum current of battery, calculate and availablely input or output power according to the associated voltage in test process, Time Calculation are maximum.

Table 1

	-20℃	-10℃	0℃	10℃	15℃	20℃	25℃	45℃	55℃	60℃	65℃
												0％	0	0	0	0	0	0	0	0	0	0	0
5％	5	5	5	5	5	5	5	5	5	5	0
												10％	5	5	5	5	10	10	10	10	5	5	0
15％	10	10	10	10	15	20	20	20	10	5	0
												20％	10	10	10	15	20	30	40	40	10	5	0
25％	10	20	20	20	30	50	60	60	10	5	0
												30％	10	20	30	30	40	60	70	70	10	5	0
40％	10	30	30	40	50	70	80	80	10	5	0
												50％	10	40	40	60	70	80	80	80	10	5	0
60％	10	40	40	60	70	80	80	80	10	5	0
												70％	10	40	40	60	70	80	90	80	10	5	0
80％	10	40	50	60	70	80	90	80	10	5	0
												90％	10	40	50	60	70	80	90	80	10	5	0
100％	10	40	50	60	70	80	90	80	10	5	0

Wherein, because a HPPC pulse can only obtain a performance number under a temperature, SOC point, therefore will obtain above table, a SOC point needs to test in each temperature, just can draw the content of whole form.Based on above table, in the process of battery operation, by BMS (Battery Management System, battery management system) battery current state is estimated, the temperature of such as present battery is in 20 DEG C, SOC is under 50% state, then can draw battery maximum allowable power be 20 DEG C with the performance number 80 kilowatts at 50% point of crossing place.If battery current state is not be on form point of crossing just at the right time, then BMS is also needed to adopt interpolation method to draw performance number.Such as battery temperature be in 17 DEG C with SOC be under 50% state, then need by 20 DEG C, the performance number under 50% state 80 kilowatts with 15 DEG C, the 70 kilowatts of interpolation methods of the performance number under 50% state draw, for linear interpolation:

Show that battery is in the performance number 74 kilowatts being in current state (it is 50% that temperature is in 17 DEG C with SOC) with crossing said method, in like manner also can obtain temperature in form point of crossing, and SOC not on form point of crossing time maximum allowable power, the battery status all not on form point of crossing for temperature and SOC, can fully utilize said method and obtain its maximum allowable power.

In addition, the state variable of battery, except SOC, temperature, can also have ageing state etc.Wherein, because battery is in use use continuously, therefore said method also can run continuously, obtains the state variable of battery continuously, thus draws the maximum allowable power of battery continuously.

But, by carrying out continuously in vehicle operation calculating in correlation technique, such as in the t0 moment, the state variable of battery system is SOC1, T1, the performance number drawn by the method in correlation technique is P1, represent under present battery status, battery system (can equal minimum or ceiling voltage limit value with steady current electric discharge at 10s end cell voltage in other words with the power discharge of P1 or charging 10s, see current limit or voltage restriction), and in battery t1 moment after after a while as 5s, the state variable of battery becomes SOC2, T2, the maximum allowable power P2 drawn by method in correlation technique.It should be noted that, the meaning that in fact P2 represents is that shelve 1h under SOC2, T2 state after, battery can carry out exporting or inputting 10s with P2, and in fact, because battery to have carried out electric discharge or the charging in 5 seconds according to P1 power in t0 ~ t1 moment, the degree of polarization of battery with HPPC test when each pulse starts to shelve 1h completely different, then now battery reality input or output performance number in theory lower than P2, once load is carried out inputing or outputing according to P2, battery will there will be under-voltage (output) or overvoltage (input) fault.

It can thus be appreciated that polarized state is as a state of battery, and the state variable not being taken as battery is applied to the maximum allowable power calculating battery in correlation technique.Namely say, the a certain particular state of battery, if only describe not enough by SOC, temperature, because this state may be reached by electric discharge, also may be reached by charging, reached by electric discharge and pass through the state reached of charging, although SOC, temperature that can be corresponding identical, its maximum allowable power and available charge power, discharge power physical presence larger difference, easily cause calculating generation error, computational accuracy reduces, and shortens the serviceable life of battery.

The present invention just based on the problems referred to above, and proposes a kind of battery maximum allowable power computing method and a kind of battery maximum allowable power calculation element.

Describe the battery maximum allowable power computing method and device that propose according to the embodiment of the present invention with reference to the accompanying drawings, describe the battery maximum allowable power computing method proposed according to the embodiment of the present invention first with reference to the accompanying drawings.With reference to shown in Fig. 1, the method comprises the following steps:

S101, obtain the polarized state of battery during kth time sampling and obtain polarized state parameter and the state-of-charge of battery, wherein, k is positive integer.

Wherein, in one embodiment of the invention, with reference to shown in Fig. 2, when obtaining kth time sampling by the battery equivalent electrical circuit with a RC circuit 10 and the 2nd RC circuit 20 battery polarized state and obtain polarized state parameter and the state-of-charge of battery.Wherein, voltage source 30 simulated battery in figure, voltage source 30 can export different voltage according to the state-of-charge of battery.

S102, polarized state parameter when sampling according to kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, obtained the polarized state parameter of battery by following formula, formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance R1 of a RC circuit 10, R _lrepresent the second resistance R2 of the 2nd RC circuit 20, C _srepresent the first electric capacity C1 of a RC circuit 10, C _lrepresent the second electric capacity C2 of the 2nd RC circuit 20, U _srepresent the voltage of the first resistance R1, U _lrepresent the voltage of the second resistance R2, i _(k)the electric current of battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance R1 during kth+nT sampling, U _{l (k+nT)}represent the voltage of the second resistance R2 during kth+nT sampling.

S103, state-of-charge when sampling according to kth time and the actual capacity of battery calculate the state-of-charge of battery when sampling for kth+nT time.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, obtained the state-of-charge of battery by energy accumulation approach, formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\η}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of battery when representing that kth time is sampled, C represents the actual capacity of battery, and η represents the coulombic efficiency of battery, SOC _(k+nT)represent the state-of-charge of battery during kth+nT sampling.

Particularly, with reference to shown in Fig. 2, the reaction mechanism more complicated of inside battery, adopts battery equivalent electrical circuit to simulate the response characteristic describing battery, by voltage source 30 simulated battery usually.Wherein, U _oCrepresent that battery is as the electromotive force of voltage source 30, R ₀represent that the ohmic internal resistance of voltage source 30 and the internal resistance R3 of voltage source 30, the first resistance R1, the second resistance R2, the first electric capacity C1, the second electric capacity C2 are respectively the element representing battery transient response characteristic.Use U _srepresent the voltage at the first resistance R1 two ends, use U _lrepresent the voltage at the second resistance R2 two ends, U represents the terminal voltage of voltage source 30, and i represents the charging and discharging currents of voltage source 30, and discharge for just, be charged as negative, then this battery equivalent electrical circuit can with the response characteristic of satisfied precision analog battery.Namely say, in the state of k moment cells known equivalent electrical circuit, then can extrapolate the state of the battery equivalent electrical circuit in k+nT (T is the sampling period, and n is positive integer) moment according to the exciting current in circuit.Be sampled as example with k+1 time below simply to set forth, this battery equivalent electrical circuit can describe in order to lower system of equations:

$\left(\begin{array}{c}{\stackrel{\·}{U}}_s\\ {\stackrel{\·}{U}}_l\end{array}\right)=\left(\begin{array}{cc}-\frac{1}{C_s{R}_s}& 0\\ 0& -\frac{1}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{1}{C_s}\\ \frac{1}{C_l}\end{array}\right)i,$ (formula 1)

U＝U _OC-R ₀i-U _s-U _l

Wherein, U _sand U _ltwo parameters represent the polarized state of voltage source 30 respectively, can use, carry out discretize to system of equations as the state variable of voltage source 30, order

$\begin{array}{c}{\stackrel{\·}{U}}_s=\frac{U_{s(k+1)}-U_{s\left(k\right)}}{T}\\ {\stackrel{\·}{U}}_l=\frac{U_{l(k+1)}-U_{l\left(k\right)}}{T}\end{array},$

Wherein, k represents the kth time sampling of certain state variable, and k+1 represents kth+1 sampling of certain state variable, as U _{s (k)}the voltage of the first resistance R1 in battery equivalent electrical circuit when representing kth time sampling, T represents the sampling period, and after discretize, system of equations becomes:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Further, be the short time characteristics such as 10s, 30s due to what usually adopt when predicting the maximum allowable power of battery, therefore at short notice, the SOC of voltage source 30 can obtain by power consumption cumulative method:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\η}{\mathrm{Ti}}_{\left(k\right)}}{C},$ (formula 2)

Wherein, SOC represents the state-of-charge of voltage source 30, and C represents the actual capacity of voltage source 30, and η is the coulombic efficiency of voltage source 30, then have:

$\left(\begin{array}{c}{\mathrm{SOC}}_{(k+1)}\\ U_{s(k+1)}\\ U_{l(k+1)}\end{array}\right)=\left(\begin{array}{ccc}1& 0& 0\\ 0& 1-\frac{T}{C_s{R}_s}& 0\\ 0& 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{\mathrm{SOC}}_{\left(k\right)}\\ U_{s\left(k\right)}\\ U_{l\left(k\right)}\end{array}\right)+\left(\begin{array}{c}-\frac{\mathrm{\ηT}}{C}\\ \frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$ (formula 3)

Then have according to formula 1:

U _(k+1)=U _{oc (k+1)}-R _{0 (k+1)}i _(k+1)-U _{s (k+1)}-U _{l (k+1)}, (formula 4)

Further, make $x=\left(\begin{array}{c}\mathrm{SOC}\\ U_s\\ U_l\end{array}\right),A=\left(\begin{array}{ccc}1& 0& 0\\ 0& 1-\frac{T}{C_s{R}_s}& 0\\ 0& 0& 1-\frac{T}{C_l{R}_l}\end{array}\right),B=\left(\begin{array}{c}-\frac{\mathrm{\ηT}}{C}\\ \frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right),$ Then formula 3 can be expressed as:

U _(k+1)＝U _oc(k+1)-R _0(k+1)i _(k+1)-(0 1 1)x _(k+1)。

S104, when sampling according to polarized state parameter during kth+nT sampling and kth+nT time, the state-of-charge of battery calculates the maximum allowable power of the battery when kth+nT sampling.

Further, in one embodiment of the invention, the embodiment of the present invention with need predict 10s from the kth moment (representing for subscript k+100) after maximum discharge power, suppose that sampling period T is 0.1s, monomer minimum is made as Vmin, after 10s, then calculate the voltage of k+100 moment voltage source 30 with the voltage of k moment voltage source 30, have following formula:

U _(k+100)=U _{oc (k+100)}-R _{0 (k+100)}i _(k+100)-(0 1 1) x _(k+100)>Vmin, (formula 5)

It should be noted that, because the internal resistance R3 of voltage source 30 is relatively constant, can think that it changes in 10s less, therefore the embodiment of the present invention is thought:

R _{0 (k+100)}=R _{0 (k)}, (formula 6)

Due in 10s be steady current electric discharge, i _(k+100)=i _(k)=i, and have unique corresponding relation due to OCV (Open circuit voltage, open-circuit voltage) and SOC, then within the short time of 10s, think that the corresponding relation of OCV and SOC is approximately linear, then:

U _oc(k+100)＝U _oc(k)+κ(SOC _(k+100)-SOC _(k))，

Wherein, К represents that the homologous thread of OCV and SOC is at SOC _(k)the tangent slope at place, then according to formula 2, formula 6 can be rewritten into:

$U_{\mathrm{oc}(k+100)}=U_{\mathrm{oc}\left(k\right)}+\mathrm{\κ}\frac{100\mathrm{\ηTi}}{C},$ (formula 7)

Can draw according to formula 3 again:

$x_{(k+100)}=\underset{n=1}{\overset{100}{\mathrm{\Σ}}}{A}^n{\mathrm{Bx}}_{\left(k\right)}+\mathrm{Bi}=A^{100}{x}_k+\left(\underset{n=0}{\overset{99}{\mathrm{\Σ}}}{A}^n\right)\mathrm{Bi},$ (formula 8)

Further, formula 6, formula 7, formula 8 are substituted into formula 5 and obtain:

$U_{\mathrm{oc}\left(k\right)}+\mathrm{\κ}\frac{100\mathrm{\ηTi}}{C}-R_{0}i-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)[A^{100}{x}_k+\left(\underset{n=0}{\overset{99}{\mathrm{\Σ}}}{A}^n\right)\mathrm{Bi}]>V_{\min },$ (formula 9)

Can obtain according to formula 9:

$i<\frac{U_{\mathrm{oc}\left(k\right)}-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)A^{100}{x}_{\left(k\right)}-V_{\min }}{R_0-\mathrm{\&kappa;}\frac{100\mathrm{\&eta;T}}{C}+\left(\begin{array}{ccc}0& 1& 1\end{array}\right)\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)B},$ (formula 10)

Wherein, be the known quantity in k moment on the right of the inequality of formula 10, then can show that the maximum discharge current from the k moment after 10s is i, maximum allowable power is i × V _min.

Further, for maximum permission charge power, similarly have:

$i>\frac{U_{\mathrm{oc}\left(k\right)}-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)A^{100}{x}_{\left(k\right)}-V_{\max }}{R_0-\mathrm{\&kappa;}\frac{100\mathrm{\&eta;T}}{C}+\left(\begin{array}{ccc}0& 1& 1\end{array}\right)\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)B}.$ (formula 11)

In sum, to discharge: make voltage source 30 just in time drop to V after obtaining 10s _minelectric current (during with this current discharge, the output power of battery is maximum), the embodiment of the present invention make use of the response characteristic that a battery equivalent-circuit model carrys out simulated battery, and by the output (terminal voltage U) of the battery equivalent electrical circuit form of recurrence equation input (the exciting current i from current state and battery equivalent electrical circuit, unknown quantity) draw, and due to exciting current i the unknown, the embodiment of the present invention make use of and is rationally similar to simplify inequality 5, thus obtain maximum permission discharge current by the method for separating inequality 9, and then obtain maximum permission discharge power.When the original state of battery equivalent electrical circuit, because voltage source 30 does not live through electric discharge or charging, so there is no polarization phenomena, therefore U _sand U _lbe 0.

In one embodiment of the invention, the embodiment of the present invention, to have the battery equivalent electrical circuit of two RC circuit, also can be reduced to a RC circuit or increase to the RC circuit of more than three.Wherein, be formula 1 according to descriptive equation, the embodiment of the present invention make use of its recurrence equation, when unknown exciting current, must send as an envoy to battery the terminal voltage short time (electric discharge namely will predicted or charging duration, as 10s) in the minimum permission sparking voltage V that drops to or be raised to _minor the highest permission charging voltage V _maxrequired electric current, and according to this electric current and V _min, V _maxshow that maximum allowable power and maximum permission are discharged or charge power.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, said method also comprises: the internal resistance obtaining battery according to the temperature of battery and state-of-charge.Namely say, in the embodiment of the present invention, internal resistance such as the internal resistance R3 of voltage source 30 of battery can be different with SOC and different with temperature, therefore can by the data form of surveying in advance with SOC and temperature for output quantity, table look-up and draw.

In an embodiment of the present invention, the embodiment of the present invention may be used for the calculating of the maximum charge and discharge power of cell, thus also can draw the peak power (battery system is formed by cell connection in series-parallel) of battery system according to the maximum allowable power of cell, and the state variable describing battery adds U _s, U _lthe state variable of two batteries, take into full account that the polarization effect of battery calculates the impact produced on battery maximum allowable power, thus the maximum permission electric discharge of battery after the short time (as 10s) can be doped more accurately, charge power, and after the embodiment of the present invention can dope the different time periods neatly, as 5s, 10s, 20s, maximum permission charging after 30s, discharge power, do not require a great deal of time and carry out actual measurement experiment, and can avoid because actual measurement experiment cannot consider the error that battery polarization state complicated and changeable causes, improve computational accuracy, realize in the operation or charging process of vehicle based on the current state (SOC of battery, polarized state) predict that battery can for load certain hour (for 10s) maximum allowable power in real time.

According to the battery maximum allowable power computing method that the embodiment of the present invention proposes, during by obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of battery, to calculate polarized state parameter during kth+nT sampling according to polarized state parameter, and state-of-charge when calculating kth+nT sampling according to the actual capacity of state-of-charge and battery, thus the maximum allowable power of the battery when sampling for kth+nT time is calculated according to polarized state parameter during kth+nT sampling and state-of-charge, the maximum allowable power of polarized state to battery utilizing battery equivalent electrical circuit to increase battery calculates, make the maximum allowable power that calculates more accurate, realize presetting battery maximum allowable power in a short time, reduce the error of calculation, improve computational accuracy, and calculate simple and convenient, ensure the serviceable life of battery better.

Next describes the battery maximum allowable power calculation element proposed according to the embodiment of the present invention with reference to the accompanying drawings.With reference to shown in Fig. 3, this calculation element 100 comprises: the first acquisition module 101, state parameter computing module 102, state-of-charge computing module 103 and permission power computation module 104.

Wherein, when the first acquisition module 101 is for obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of battery, wherein, k is positive integer.Polarized state parameter when state parameter computing module 102 is for sampling according to kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period.State-of-charge when state-of-charge computing module 103 is for sampling according to kth time and the actual capacity of battery calculate the state-of-charge of battery when sampling for kth+nT time.When allowing power computation module 104 for sampling according to polarized state parameter during kth+nT sampling and kth+nT time, the state-of-charge of battery calculates the maximum allowable power of the battery when kth+nT sampling.

In one embodiment of the invention, with reference to shown in Fig. 2, when the first acquisition module 101 obtains kth time sampling by the battery equivalent electrical circuit with a RC circuit 10 and the 2nd RC circuit 20 battery polarized state and obtain polarized state parameter and the state-of-charge of battery 30.Wherein, voltage source 30 simulated battery in figure, voltage source 30 can export different voltage according to the state-of-charge of battery.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, logical state parameter computing module 102 cross with polarized state parameter, formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance R1 of a RC circuit 10, R _lrepresent the second resistance R2 of the 2nd RC circuit 20, C _srepresent the first electric capacity C1 of a RC circuit 10, C _lrepresent the second electric capacity C2 of the 2nd RC circuit 20, U _srepresent the voltage of the first resistance R1, U _lrepresent the voltage of the second resistance R2, i _(k)the electric current of battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance R1 during kth+nT sampling, U _{l (k+nT)}represent the voltage of the second resistance R2 during kth+nT sampling.

S103, state-of-charge when sampling according to kth time and the actual capacity of battery calculate the state-of-charge of battery when sampling for kth+nT time.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, state-of-charge computing module 103 obtains the state-of-charge of battery by energy accumulation approach, and formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\&eta;}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of battery when representing that kth time is sampled, C represents the actual capacity of battery, and η represents the coulombic efficiency of battery, SOC _(k+nT)represent the state-of-charge of battery during kth+nT sampling.

Particularly, with reference to shown in Fig. 2, the reaction mechanism more complicated of inside battery, adopts battery equivalent electrical circuit to simulate the response characteristic describing battery, by voltage source 30 simulated battery usually.Wherein, U _oCrepresent that battery is as the electromotive force of voltage source 30, R ₀represent that the ohmic internal resistance of voltage source 30 and the internal resistance R3 of voltage source 30, the first resistance R1, the second resistance R2, the first electric capacity C1, the second electric capacity C2 are respectively the element representing battery transient response characteristic.Use U _srepresent the voltage at the first resistance R1 two ends, use U _lrepresent the voltage at the second resistance R2 two ends, U represents the terminal voltage of voltage source 30, and i represents the charging and discharging currents of voltage source 30, and discharge for just, be charged as negative, then this battery equivalent electrical circuit can with the response characteristic of satisfied precision analog battery.Namely say, in the state of k moment cells known equivalent electrical circuit, then can extrapolate the state of the battery equivalent electrical circuit in k+nT (T is the sampling period, and n is positive integer) moment according to the exciting current in circuit.Be sampled as example with k+1 time below simply to set forth, this battery equivalent electrical circuit can describe in order to lower system of equations:

$\left(\begin{array}{c}{\stackrel{\&CenterDot;}{U}}_s\\ {\stackrel{\&CenterDot;}{U}}_l\end{array}\right)=\left(\begin{array}{cc}-\frac{1}{C_s{R}_s}& 0\\ 0& -\frac{1}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{1}{C_s}\\ \frac{1}{C_l}\end{array}\right)i,$ (formula 1)

U＝U _OC-R ₀i-U _s-U _l

Wherein, U _sand U _ltwo parameters represent the polarized state of voltage source 30 respectively, can use, carry out discretize to system of equations as the state variable of voltage source 30, order

$\begin{array}{c}{\stackrel{\&CenterDot;}{U}}_s=\frac{U_{s(k+1)}-U_{s\left(k\right)}}{T}\\ {\stackrel{\&CenterDot;}{U}}_l=\frac{U_{l(k+1)}-U_{l\left(k\right)}}{T}\end{array},$

Wherein, k represents the kth time sampling of certain state variable, and k+1 represents kth+1 sampling of certain state variable, as U _{s (k)}the voltage of the first resistance R1 in battery equivalent electrical circuit when representing kth time sampling, T represents the sampling period, and after discretize, system of equations becomes:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Further, be the short time characteristics such as 10s, 30s due to what usually adopt when predicting the maximum allowable power of battery, therefore at short notice, the SOC of voltage source 30 can obtain by power consumption cumulative method:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\&eta;}{\mathrm{Ti}}_{\left(k\right)}}{C},$ (formula 2)

Wherein, SOC represents the state-of-charge of voltage source 30, and C represents the actual capacity of voltage source 30, and η is the coulombic efficiency of voltage source 30, then have:

$\left(\begin{array}{c}{\mathrm{SOC}}_{(k+1)}\\ U_{s(k+1)}\\ U_{l(k+1)}\end{array}\right)=\left(\begin{array}{ccc}1& 0& 0\\ 0& 1-\frac{T}{C_s{R}_s}& 0\\ 0& 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{\mathrm{SOC}}_{\left(k\right)}\\ U_{s\left(k\right)}\\ U_{l\left(k\right)}\end{array}\right)+\left(\begin{array}{c}-\frac{\mathrm{\&eta;T}}{C}\\ \frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$ (formula 3)

Then have according to formula 1:

U _(k+1)=U _{oc (k+1)}-R _{0 (k+1)}i _(k+1)-U _{s (k+1)}-U _{l (k+1)}, (formula 4)

Further, make $x=\left(\begin{array}{c}\mathrm{SOC}\\ U_s\\ U_l\end{array}\right),A=\left(\begin{array}{ccc}1& 0& 0\\ 0& 1-\frac{T}{C_s{R}_s}& 0\\ 0& 0& 1-\frac{T}{C_l{R}_l}\end{array}\right),B=\left(\begin{array}{c}-\frac{\mathrm{\&eta;T}}{C}\\ \frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right),$ Then formula 3 can be expressed as:

U _(k+1)＝U _oc(k+1)-R _0(k+1)i _(k+1)-(0 1 1)x _(k+1)。

Further, in one embodiment of the invention, the embodiment of the present invention with need predict 10s from the kth moment (representing for subscript k+100) after maximum discharge power, suppose that sampling period T is 0.1s, monomer minimum is made as Vmin, after 10s, then calculate the voltage of k+100 moment voltage source 30 with the voltage of k moment voltage source 30, have following formula:

U _(k+100)=U _{oc (k+100)}-R _{0 (k+100)}i _(k+100)-(0 1 1) x _(k+100)>Vmin, (formula 5)

It should be noted that, because the internal resistance R3 of voltage source 30 is relatively constant, can think that it becomes smaller in 10s, therefore the embodiment of the present invention is thought:

R _{0 (k+100)}=R _{0 (k)}, (formula 6)

Due in 10s be steady current electric discharge, i _(k+100)=i _(k)=i, and have unique corresponding relation due to OCV and SOC, then within the short time of 10s, think that the corresponding relation of OCV and SOC is approximately linear, then:

U _oc(k+100)＝U _oc(k)+κ(SOC _(k+100)-SOC _(k))，

Wherein, К represents that the homologous thread of OCV and SOC is at SOC _(k)the tangent slope at place, then according to formula 2, formula 6 can be rewritten into:

$U_{\mathrm{oc}(k+100)}=U_{\mathrm{oc}\left(k\right)}+\mathrm{\&kappa;}\frac{100\mathrm{\&eta;Ti}}{C},$ (formula 7)

Can draw according to formula 3 again:

$x_{(k+100)}=\underset{n=1}{\overset{100}{\mathrm{\&Sigma;}}}{A}^n{\mathrm{Bx}}_{\left(k\right)}+\mathrm{Bi}=A^{100}{x}_k+\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)\mathrm{Bi},$ (formula 8)

Further, formula 6, formula 7, formula 8 are substituted into formula 5 and obtain:

$U_{\mathrm{oc}\left(k\right)}+\mathrm{\&kappa;}\frac{100\mathrm{\&eta;Ti}}{C}-R_{0}i-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)[A^{100}{x}_k+\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)\mathrm{Bi}]>V_{\min },$ (formula 9)

Can obtain according to formula 9:

$i<\frac{U_{\mathrm{oc}\left(k\right)}-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)A^{100}{x}_{\left(k\right)}-V_{\min }}{R_0-\mathrm{\&kappa;}\frac{100\mathrm{\&eta;T}}{C}+\left(\begin{array}{ccc}0& 1& 1\end{array}\right)\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)B},$ (formula 10)

Wherein, be the known quantity in k moment on the right of the inequality of formula 10, then can show that the maximum discharge current from the k moment after 10s is i, maximum allowable power is i × V _min.

Further, for maximum permission charge power, similarly have:

$i>\frac{U_{\mathrm{oc}\left(k\right)}-\left(\begin{array}{ccc}0& 1& 1\end{array}\right)A^{100}{x}_{\left(k\right)}-V_{\max }}{R_0-\mathrm{\&kappa;}\frac{100\mathrm{\&eta;T}}{C}+\left(\begin{array}{ccc}0& 1& 1\end{array}\right)\left(\underset{n=0}{\overset{99}{\mathrm{\&Sigma;}}}{A}^n\right)B}.$ (formula 11)

In sum, to discharge: make voltage source 30 just in time drop to V after obtaining 10s _minelectric current (during with this current discharge, the output power of battery is maximum), the embodiment of the present invention make use of the response characteristic that a battery equivalent-circuit model carrys out simulated battery, and by the output (terminal voltage U) of the battery equivalent electrical circuit form of recurrence equation input (the exciting current i from current state and battery equivalent electrical circuit, unknown quantity) draw, and due to exciting current i the unknown, the embodiment of the present invention make use of and is rationally similar to simplify inequality 5, thus obtain maximum permission discharge current by the method for separating inequality 9, and then obtain maximum permission discharge power.When the original state of battery equivalent electrical circuit, because voltage source 30 does not live through electric discharge or charging, so there is no polarization phenomena, therefore U _sand U _lbe 0.

In one embodiment of the invention, the embodiment of the present invention, to have the battery equivalent electrical circuit of two RC circuit, also can be reduced to a RC circuit or increase to the RC circuit of more than three.Wherein, be formula 1 according to descriptive equation, the embodiment of the present invention make use of its recurrence equation, when unknown exciting current, must send as an envoy to battery the terminal voltage short time (electric discharge namely will predicted or charging duration, as 10s) in the minimum permission sparking voltage V that drops to or be raised to _minor the highest permission charging voltage V _maxrequired electric current, and according to this electric current and V _min, V _maxshow that maximum allowable power and maximum permission are discharged or charge power.

Further, in one embodiment of the invention, with reference to shown in Fig. 2, above-mentioned calculation element 100 also comprises: the second acquisition module 105.Wherein, the second acquisition module 105 is for obtaining the internal resistance of battery according to the temperature of battery and state-of-charge.Namely say, in the embodiment of the present invention, internal resistance such as the internal resistance R3 of voltage source 30 of battery can be different with SOC and different with temperature, therefore can by the data form of surveying in advance with SOC and temperature for output quantity, table look-up and draw.

In an embodiment of the present invention, the embodiment of the present invention may be used for the calculating of the maximum charge and discharge power of cell, thus also can draw the peak power (battery system is formed by cell connection in series-parallel) of battery system according to the maximum allowable power of cell, and the state variable describing battery adds U _s, U _lthe state variable of two batteries, take into full account that the polarization effect of battery calculates the impact produced on battery maximum allowable power, thus the maximum permission electric discharge of battery after the short time (as 10s) can be doped more accurately, charge power, and after the embodiment of the present invention can dope the different time periods neatly, as 5s, 10s, 20s, maximum permission charging after 30s, discharge power, do not require a great deal of time and carry out actual measurement experiment, and can avoid because actual measurement experiment cannot consider the error that battery polarization state complicated and changeable causes, improve computational accuracy, realize in the operation or charging process of vehicle based on the current state (SOC of battery, polarized state) predict that battery can for load certain hour (for 10s) maximum allowable power in real time.

According to the battery maximum allowable power calculation element that the embodiment of the present invention proposes, during by obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of battery, to calculate polarized state parameter during kth+nT sampling according to polarized state parameter, and state-of-charge when calculating kth+nT sampling according to the actual capacity of state-of-charge and battery, thus calculate the maximum allowable power after the kth moment starts nT according to polarized state parameter during kth+nT sampling and state-of-charge, the maximum allowable power of polarized state to battery utilizing battery equivalent electrical circuit to increase battery calculates, make the maximum allowable power that calculates more accurate, realize presetting battery maximum allowable power in a short time, reduce the error of calculation, improve computational accuracy, and calculate simple and convenient, ensure the serviceable life of battery better.

Describe and can be understood in process flow diagram or in this any process otherwise described or method, represent and comprise one or more for realizing the module of the code of the executable instruction of the step of specific logical function or process, fragment or part, and the scope of the preferred embodiment of the present invention comprises other realization, wherein can not according to order that is shown or that discuss, comprise according to involved function by the mode while of basic or by contrary order, carry out n-back test, this should understand by embodiments of the invention person of ordinary skill in the field.

In flow charts represent or in this logic otherwise described and/or step, such as, the sequencing list of the executable instruction for realizing logic function can be considered to, may be embodied in any computer-readable medium, for instruction execution system, device or equipment (as computer based system, comprise the system of processor or other can from instruction execution system, device or equipment instruction fetch and perform the system of instruction) use, or to use in conjunction with these instruction execution systems, device or equipment.With regard to this instructions, " computer-readable medium " can be anyly can to comprise, store, communicate, propagate or transmission procedure for instruction execution system, device or equipment or the device that uses in conjunction with these instruction execution systems, device or equipment.The example more specifically (non-exhaustive list) of computer-readable medium comprises following: the electrical connection section (electronic installation) with one or more wiring, portable computer diskette box (magnetic device), random access memory (RAM), ROM (read-only memory) (ROM), erasablely edit ROM (read-only memory) (EPROM or flash memory), fiber device, and portable optic disk ROM (read-only memory) (CDROM).In addition, computer-readable medium can be even paper or other suitable media that can print described program thereon, because can such as by carrying out optical scanning to paper or other media, then carry out editing, decipher or carry out process with other suitable methods if desired and electronically obtain described program, be then stored in computer memory.

Should be appreciated that each several part of the present invention can realize with hardware, software, firmware or their combination.In the above-described embodiment, multiple step or method can with to store in memory and the software performed by suitable instruction execution system or firmware realize.Such as, if realized with hardware, the same in another embodiment, can realize by any one in following technology well known in the art or their combination: the discrete logic with the logic gates for realizing logic function to data-signal, there is the special IC of suitable combinational logic gate circuit, programmable gate array (PGA), field programmable gate array (FPGA) etc.

Those skilled in the art are appreciated that realizing all or part of step that above-described embodiment method carries is that the hardware that can carry out instruction relevant by program completes, described program can be stored in a kind of computer-readable recording medium, this program perform time, step comprising embodiment of the method one or a combination set of.

In addition, each functional unit in each embodiment of the present invention can be integrated in a processing module, also can be that the independent physics of unit exists, also can be integrated in a module by two or more unit.Above-mentioned integrated module both can adopt the form of hardware to realize, and the form of software function module also can be adopted to realize.If described integrated module using the form of software function module realize and as independently production marketing or use time, also can be stored in a computer read/write memory medium.

The above-mentioned storage medium mentioned can be ROM (read-only memory), disk or CD etc.

In the description of this instructions, specific features, structure, material or feature that the description of reference term " embodiment ", " some embodiments ", " example ", " concrete example " or " some examples " etc. means to describe in conjunction with this embodiment or example are contained at least one embodiment of the present invention or example.In this manual, identical embodiment or example are not necessarily referred to the schematic representation of above-mentioned term.And the specific features of description, structure, material or feature can combine in an appropriate manner in any one or more embodiment or example.

Although illustrate and describe embodiments of the invention above, be understandable that, above-described embodiment is exemplary, can not be interpreted as limitation of the present invention, those of ordinary skill in the art can change above-described embodiment within the scope of the invention when not departing from principle of the present invention and aim, revising, replacing and modification.

Claims (10)

1. battery maximum allowable power computing method, is characterized in that, comprise the following steps:

Obtain the polarized state of battery during kth time sampling and obtain polarized state parameter and the state-of-charge of described battery, wherein, k is positive integer;

Polarized state parameter when sampling according to described kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period;

State-of-charge when sampling according to described kth time and the actual capacity of described battery calculate the state-of-charge of described battery when sampling for described kth+nT time; And

When sampling according to polarized state parameter during described kth+nT sampling and described kth+nT time, the state-of-charge of described battery calculates the maximum allowable power of the described battery when described kth+nT sampling.

2. battery maximum allowable power computing method as claimed in claim 1, its feature exists, when obtaining kth time sampling by the battery equivalent electrical circuit with a RC circuit and the 2nd RC circuit described battery polarized state and obtain polarized state parameter and the state-of-charge of described battery.

3. battery maximum allowable power computing method as claimed in claim 2, it is characterized in that, obtained the polarized state parameter of described battery by following formula, described formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance of a described RC circuit, R _lrepresent the second resistance of described 2nd RC circuit, C _srepresent the first electric capacity of a described RC circuit, C _lrepresent the second electric capacity of described 2nd RC circuit, U _srepresent the voltage of described first resistance, U _lrepresent the voltage of described second resistance, i _(k)the electric current of described battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance described in when sampling for kth+nT time, U _{l (k+nT)}represent the voltage of the second resistance described in when sampling for kth+nT time.

4. battery maximum allowable power computing method as claimed in claim 3, it is characterized in that, obtained the state-of-charge of described battery by energy accumulation approach, formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\&eta;}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of described battery when representing that kth time is sampled, C represents the actual capacity of described battery, and η represents the coulombic efficiency of described battery, SOC _(k+nT)represent the state-of-charge of described battery during kth+nT sampling.

5. battery maximum allowable power computing method as claimed in claim 1, is characterized in that, also comprise: the internal resistance obtaining described battery according to the temperature of described battery and state-of-charge.

6. a battery maximum allowable power calculation element, is characterized in that, comprising:

First acquisition module, during for obtaining kth time sampling battery polarized state and obtain polarized state parameter and the state-of-charge of described battery, wherein, k is positive integer;

State parameter computing module, polarized state parameter during for sampling according to described kth time calculates polarized state parameter during kth+nT sampling, and wherein, n is positive integer, and T is the sampling period;

State-of-charge computing module, state-of-charge during for sampling according to described kth time and the actual capacity of described battery calculate the state-of-charge of described battery when sampling for described kth+nT time; And

Allow power computation module, during for sampling according to polarized state parameter during described kth+nT sampling and described kth+nT time, the state-of-charge of described battery calculates the maximum allowable power of the described battery when described kth+nT sampling.

7. battery maximum allowable power calculation element as claimed in claim 6, it is characterized in that, when described first acquisition module obtains kth time sampling by the battery equivalent electrical circuit with a RC circuit and the 2nd RC circuit described battery polarized state and obtain polarized state parameter and the state-of-charge of described battery.

8. battery maximum allowable power calculation element as claimed in claim 7, it is characterized in that, described state parameter computing module obtains the polarized state parameter of described battery by following formula, and described formula is:

$\left(\begin{array}{c}{U}_{s(k+\mathrm{nT})}\\ U_{l(k+\mathrm{nT})}\end{array}\right)=\left(\begin{array}{cc}1-\frac{T}{C_s{R}_s}& 0\\ 0& 1-\frac{T}{C_l{R}_l}\end{array}\right)\left(\begin{array}{c}{U}_s\\ U_l\end{array}\right)+\left(\begin{array}{c}\frac{T}{C_s}\\ \frac{T}{C_l}\end{array}\right)i_{\left(k\right)},$

Wherein, R _srepresent the first resistance of a described RC circuit, R _lrepresent the second resistance of described 2nd RC circuit, C _srepresent the first electric capacity of a described RC circuit, C _lrepresent the second electric capacity of described 2nd RC circuit, U _srepresent the voltage of described first resistance, U _lrepresent the voltage of described second resistance, i _(k)the electric current of described battery equivalent electrical circuit when representing that kth time is sampled, U _{s (k+nT)}represent the voltage of the first resistance described in when sampling for kth+nT time, U _{l (k+nT)}represent the voltage of the second resistance described in when sampling for kth+nT time.

9. battery maximum allowable power calculation element as claimed in claim 8, it is characterized in that, described state-of-charge computing module obtains the state-of-charge of described battery by energy accumulation approach, formula is:

${\mathrm{SOC}}_{(k+\mathrm{nT})}={\mathrm{SOC}}_{\left(k\right)}-\frac{\mathrm{\&eta;}{\mathrm{Ti}}_{\left(k\right)}}{C},$

Wherein, SOC _(k)the state-of-charge of described battery when representing that kth time is sampled, C represents the actual capacity of described battery, and η represents the coulombic efficiency of described battery, SOC _(k+nT)represent the state-of-charge of described battery during kth+nT sampling.

10. battery maximum allowable power calculation element as claimed in claim 6, is characterized in that, also comprise:

Second acquisition module, for obtaining the internal resistance of described battery according to the temperature of described battery and state-of-charge.