JP5655050B2 - Generator control device - Google Patents

Description

  The present invention relates to a generator control device mounted on a vehicle and driven by an internal combustion engine.

  Patent Document 1 discloses a control device for a generator mounted on a vehicle and driven by an internal combustion engine. According to this control device, during the fuel cut operation of the engine, the power generation voltage of the generator is increased and the battery is forcibly charged to forcibly charge. Only the control to reduce the power generation voltage of the generator is performed.

Japanese Patent No. 3797242

  According to the above-described conventional control device, forced charging is performed each time the fuel cut operation is performed, so that the temperature of the generator-related devices such as the generator itself and wires connected to the generator rises, and heat is generated. There was a possibility of damage.

  The present invention has been made paying attention to this point, and appropriately executes high-voltage power generation that raises the power generation voltage from the output voltage of the battery, and optimizes the charge amount of the battery while suppressing the temperature rise of the generator-related device. It is an object of the present invention to provide a generator control device that can be maintained at the same time.

In order to achieve the above object, the invention described in claim 1 is capable of being charged by an internal combustion engine (2), a generator (1) driven by the engine, and electric power generated by the generator (1). A generator control device that is mounted on a vehicle including a battery (4) and controls the generator (1). The battery sensor (21) is attached to the battery (4) and acquires the state of the battery. And a power generation voltage control means for changing the power generation voltage (VACG) of the generator according to the state of the vehicle, and the power generation voltage control means stops the fuel supply to the engine. At the time of starting, it is determined whether or not the battery charge amount (IBSUM) is larger than a predetermined charge amount (α) using the output value (IB) of the battery sensor, and the charge amount (IBSUM) is determined as the predetermined charge amount (IBSUM). Charge When the amount (α) is less than or equal to the amount (α), the generator (1) performs high voltage power generation with a first high voltage (V3) higher than the output voltage (VB0) of the battery, and the charge amount is the predetermined amount When the amount of charge is larger, the generator (1) performs regenerative power generation that generates power at a second high voltage (V4) higher than the first high voltage (V3).

  According to a second aspect of the present invention, in the generator control device according to the first aspect, the power generation voltage control means is configured such that the high voltage is generated in a predetermined operation state in which the engine (2) outputs a positive torque. Power generation is performed, and the predetermined operation state is a state in which the load (PENG) of the engine is lower than the load (L1) at which the net fuel consumption rate of the engine is lowest.

  According to a third aspect of the present invention, in the generator control device according to the first or second aspect of the present invention, the generator further includes an accelerator sensor that detects an operation amount (AP) of an accelerator pedal provided in the vehicle. The driving state is a stable running state in which a difference (DAP) between a moving average value (APAV) of the detected accelerator pedal operation amount and the accelerator pedal operation amount (AP) is a predetermined value (DAPTH) or less. And

The invention according to claim 4, in the control apparatus of the generator according to claim 3, wherein the predetermined operating condition, characterized in that the stable running state is a predetermined time between (TSTB) relay state continue the .

  According to a fifth aspect of the present invention, in the generator control device according to any one of the first to fourth aspects, the battery sensor (21) acquires an input / output current value (IB) of the battery, The generated voltage control means calculates the charge amount (IBSUM) by executing the integration of the acquired current value (IB) from a preset initial value.

  According to a sixth aspect of the present invention, in the generator control device according to any one of the first to fifth aspects, the generated voltage control means uses an internal resistance of the battery using the battery sensor (21). An internal resistance value detecting means for detecting a value (RI) is provided, and the regenerative power generation is prohibited when the internal resistance value (RI) is not less than a predetermined resistance value (RITH).

  According to a seventh aspect of the present invention, in the generator control device according to any one of the first to fifth aspects, the generated voltage control means estimates an internal temperature (TB) of the battery. And regenerative power generation is prohibited when the internal temperature (TB) is equal to or higher than a predetermined temperature (TBTH).

  According to the first aspect of the present invention, at the start of the fuel cut operation for stopping the fuel supply to the engine, it is determined whether or not the charge amount of the battery is larger than the predetermined charge amount using the output value of the battery sensor. When the charge amount is less than or equal to the predetermined charge amount, high voltage power generation is performed in which the generator generates power at a first high voltage higher than the output voltage of the battery. When the charge amount is greater than the predetermined charge amount, Regenerative power generation that generates power at a second high voltage that is higher than the high voltage is performed. The battery has a characteristic that the larger the amount of charge (the higher the charging rate (SOC: State Of Charge) based on full charge)), the more difficult the battery is charged. Therefore, when the SOC is high, the amount of power charged in the battery Will be less. Therefore, one of the first and second high voltages is selected according to the amount of charge of the battery at the start of the fuel cut operation, and only when the amount of charge of the battery is large, regenerative power generation at the second high voltage. By executing the above, it is possible to suppress an increase in the temperature of the generator-related device and to extend the life while maintaining the charge amount of the battery optimally. Also, when the charge amount is less than or equal to the predetermined charge amount at the start of the fuel cut operation, even if the charge amount exceeds the predetermined charge amount after the start of the fuel cut operation, it does not shift to regenerative power generation. This can suppress the battery life extension effect.

  According to the second aspect of the present invention, high-voltage power generation is performed in a predetermined operation state where the engine outputs a positive torque. In the predetermined operation state, the engine load is the highest in the net fuel consumption rate of the engine. The load becomes lower, that is, lower than the bottom line of the net fuel consumption rate. By adding the power generation load by the generator, the engine load can be brought closer to the bottom line of the net fuel consumption rate, reducing the need to generate power in other operating areas where the amount of fuel consumed for power generation is large Fuel consumption (electricity cost).

  According to the third aspect of the present invention, since the difference between the moving average value of the detected accelerator pedal operation amount and the accelerator pedal operation amount is a predetermined travel value or less in the predetermined operation state, the accelerator operation amount is It is possible to prevent adverse effects such as flickering of light due to an increase in the frequency of changing the generated voltage in a state where the pedal operation amount varies greatly.

  According to the fourth aspect of the present invention, the predetermined operation state is a state in which the stable running state continues for a predetermined time, so that the effect of the third aspect can be achieved more reliably.

  According to the fifth aspect of the present invention, the battery input / output current value is acquired by the battery sensor, and the charge amount is calculated by executing integration of the acquired current value from a preset initial value. Therefore, an accurate charge amount can be obtained and the generated voltage control can be performed with high accuracy.

  According to the sixth aspect of the present invention, when the internal resistance value of the battery is detected and the internal resistance value is equal to or greater than the predetermined resistance value, regenerative power generation is prohibited. When regenerative power generation is performed, the value of the current flowing into the battery increases and the fluctuation range of the SOC of the battery increases, which may promote the deterioration of the battery. Further, since the internal resistance value increases as the deterioration of the battery proceeds, it is possible to prevent the battery deterioration from being promoted by prohibiting regenerative power generation when the internal resistance value is equal to or higher than a predetermined resistance value. .

  According to the seventh aspect of the present invention, the internal temperature of the battery is estimated, and regenerative power generation is prohibited when the estimated internal temperature is equal to or higher than a predetermined temperature. When the internal temperature of the battery increases, the value of the current flowing into the battery tends to increase even when the charging voltage is the same, and the battery may be overcharged to promote deterioration. Therefore, it is possible to prevent battery deterioration from being promoted by prohibiting regenerative power generation when the estimated internal temperature is equal to or higher than a predetermined temperature.

1 is a diagram illustrating a configuration of an internal combustion engine mounted on a vehicle according to an embodiment of the present invention and a control device for a generator driven by the engine. FIG. It is a flowchart of the process which controls the electric power generation voltage (VACG) of the generator shown in FIG. It is a flowchart of the process which performs the setting of the surplus load electric power generation flag (FLLD) referred by the process of FIG. It is a figure which shows the driving | running area | region defined by an engine speed (NE) and an engine output (PENG). It is a figure which shows the relationship between an engine output (PENG), a net fuel consumption rate (BSFC), and the fuel consumption per unit time (GFC). It is a time chart for demonstrating the control action by the process of FIG. It is a time chart for demonstrating the control action by the process of FIG. It is a flowchart of the process which controls a generated voltage (VACG) (2nd Embodiment). It is a flowchart of the process which controls a generated voltage (VACG) (3rd Embodiment).

Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 is a diagram showing a configuration of an internal combustion engine mounted on a vehicle according to an embodiment of the present invention and a control device for a generator driven by the engine. The generator 1 is connected to an output shaft of an internal combustion engine (hereinafter referred to as “engine”) 2 via a transmission mechanism 3 and is driven by the engine 2 to generate electric power. The generator 1 is configured to be capable of generating power with first to fourth voltages V1 to V4 (V1 <V2 <V3 <V4), and its operation is controlled by an electronic control unit (hereinafter referred to as “ECU”) 5. .

  A throttle valve 6 is provided in the intake passage of the engine 2, and the throttle valve 6 is driven by an actuator 7. The operation of the actuator 7 is controlled by the ECU 5. The ECU 5 performs drive control of a fuel injection valve and a spark plug (not shown) of the engine 2.

  The output terminal of the generator 1 is connected to the positive terminal of the battery 4 through the battery sensor 21 and is connected to one end of an electric load 10 including a motor, a headlight, etc. that drives a wiper and a power window. The other end of the electric load 10 and the negative terminal of the battery 4 are connected to ground. The battery sensor 21 detects a current IB (> 0) flowing into the battery 4 and a current IB (<0) flowing out from the battery 4, and supplies the detection signal to the ECU 5. Hereinafter, the inflowing current and the outflowing current are collectively referred to as “battery current IB”.

The ECU 5 is connected to an accelerator sensor 22 that detects an accelerator pedal operation amount (hereinafter referred to as “accelerator pedal operation amount”) AP of the vehicle, and various sensors (not shown) (for example, a rotation speed that detects the rotational speed NE of the engine 2). Several sensors, a vehicle speed sensor for detecting the vehicle traveling speed (vehicle speed) VP, a cooling water temperature sensor for detecting the engine cooling water temperature TW, and the like are connected, and detection signals from these sensors are supplied.
The ECU 5 controls the generator 1 and the engine 2 based on detection signals from various sensors.

FIG. 2 is a flowchart of a process for controlling the power generation voltage VACG of the generator 1, and this process is executed by the ECU 5 every predetermined time.
In step S11, it is determined whether or not a fuel cut flag FFC is “1”. The fuel cut flag FFC is set to “1” when a fuel cut operation for temporarily stopping the fuel supply to the engine 2 at the time of deceleration of the vehicle is executed. If the answer to step S11 is negative (NO), it is determined whether or not the surplus load power generation flag FLLD is “1” (step S12). The margin load power generation flag FLLD is set in the process of FIG. 3, and is set to “1” when permitting power generation at the third voltage V3. Therefore, when the answer to step S12 is affirmative (YES), power generation at the third voltage V3 (for example, 14.5V) (hereinafter referred to as “high voltage power generation”), the margin load power generation flag FLLD is “1”. (Also referred to as “marginal load power generation”) (step S19).

  If the answer to step S12 is negative (NO), it is determined whether or not the battery current integrated value IBSUM is “0” (step S13). Note that the determination in step S13 is actually performed by determining whether or not the absolute value of the battery current integrated value IBSUM is less than or equal to the minute predetermined value Δ. The battery current integrated value IBSUM is an initial value (“0”) when the state of charge (SOC) of the battery 4 is in a state of 75 to 90% (hereinafter referred to as “reference charge state”). The integrated value of the battery current IB. Therefore, battery current integrated value IBSUM takes a positive or negative value, and a state in which the absolute value of the negative value is large indicates a state in which the battery charge amount is smaller than the reference charge state (SOC is low).

  If the answer to step S13 is affirmative (YES), that is, if the battery 4 is in the reference charge state, the process proceeds to step S18, and power generation at the second voltage V2 (for example, 13V) (hereinafter referred to as “normal power generation”) is performed. The second voltage V2 is substantially equal to the battery output voltage (hereinafter referred to as “reference battery output voltage”) VB0 in the reference charging state, and the third voltage V3 is higher than the reference battery output voltage VB0.

  If the answer to step S13 is negative (NO), it is determined whether or not the battery current integrated value IBSUM is greater than “0” (step S14). If the answer is affirmative (YES), that is, if the SOC is higher than the reference charge state, power generation at the first voltage V1 (for example, 12V) (hereinafter referred to as “low voltage power generation”) is performed (step S17). The first voltage V1 is a voltage lower than the reference battery output voltage VB0.

  If the answer to step S14 is negative (NO), that is, if the SOC is lower than the reference charge state, high-voltage power generation at the third voltage V3 is performed (step S19).

  If the answer to step S11 is affirmative (YES), that is, if the fuel cut operation is being performed, it is determined whether or not the previous fuel cut flag FFCZ is “1” (step S15). The previous fuel cut flag FFCZ indicates the value of the fuel cut flag FFC at the previous execution of this process. Accordingly, when the answer to step S15 is affirmative (YES), this corresponds to immediately after the fuel cut flag FFC has changed from “0” to “1” (at the time of fuel cut operation start). When it is time to start the fuel cut operation, it is determined whether or not the battery current integrated value IBSUM is larger than a predetermined threshold value α (step S16). If the answer is negative (NO) and the battery 4 is in the reference charge state or in a state where the SOC is lower than that, the process proceeds to step S19 to perform high voltage power generation. The same applies when the answer to step S15 is negative (NO).

  If the answer to step S16 is affirmative (YES) and the SOC at the start of fuel cut operation is higher than the reference charge state, power generation at the fourth voltage V4 (for example, 15.5 V) (hereinafter referred to as “regenerative power generation”). (Step S20). The fourth voltage V4 is higher than the third voltage V3.

FIG. 3 is a flowchart of a process for setting the surplus load power generation flag FLLD referred to in step S12 of FIG. This process is executed by the ECU 5 every predetermined time.
In step S21, a moving average calculation of the accelerator pedal operation amount AP is executed by the following equation (1) to calculate a smoothed accelerator pedal operation amount APAV (k). K in Expression (1) is a discretization time discretized in the execution cycle of this process, and (N + 1) corresponds to the number of samples applied to the moving average calculation. The number of samples is set to an appropriate value experimentally.

In step S22, the accelerator pedal operation amount AP (k) (current value) and the smoothed accelerator pedal operation amount APAV (k) are applied to the following equation (2) to calculate the difference DAP.
DAP = | AP (k) −APAV (k) | (2)

  In step S23, it is determined whether or not the difference DAP is equal to or less than a determination threshold value DAPTH. If the answer is negative (NO), the downcount timer TMDAPL is set to a predetermined stabilization time TSTB (for example, 0.5 seconds) and started (step S24), and the surplus load power generation flag FLLD is set to “0”. Set (step S28).

  If the answer to step S23 is affirmative (YES), that is, if the difference DAP is small and the change in the accelerator pedal operation amount AP is small, it is determined whether or not the value of the timer TMDAPL is “0”. It discriminate | determines (step S25). Initially, this answer is negative (NO), and the process proceeds to step S28. When the stable running state where DAP ≦ DAPTH continues for the predetermined stabilization time TSTB, the answer to step S25 is affirmative (YES), and it is determined whether or not the surplus load operation flag FRLLD is “1” (step S26). If the answer to step S26 is affirmative (YES), the surplus load power generation flag FLLD is set to “1” to allow surplus load power generation (step S27), while the answer to step S26 is negative (NO). If so, go to Step S28.

  The margin load operation flag FRLLD is set to “1” when the engine 2 is in a predetermined margin load operation state, specifically, when the engine operation state is in the margin load operation region RLLD shown in FIG. FIG. 4 shows an operation region (NE0 shown at the left end of the figure is about 1000 rpm) defined by the engine speed NE and the engine output (power) PENG, and a solid line L1 is a so-called BSFC bottom line (net fuel). The marginal load operation region RLLD is a region below the curve L2 corresponding to the load threshold value PETH that is lower than the BSFC bottom line L1 by the marginal load PEPLS (however, the engine). The output PENG is greater than “0”). The alternate long and short dash line L3 indicates the maximum output of the engine 2.

  When the engine operating state is in the surplus load operation region RLLD, there is a surplus beyond the surplus load PEPLS up to the BSFC bottom line, so even if the surplus is used for driving the generator 1, the fuel consumption is not deteriorated. Accordingly, when the engine operating state is in the surplus load operation region RLLD, surplus load power generation (power generation at the third voltage V3) is permitted.

  FIG. 5 (a) shows the relationship between the engine output PENG and the net fuel consumption rate BSFC when the engine speed NE is constant, and the engine output PENG is lower on the lower output (lower load) side than the bottom output PEBB. As it increases, the net fuel consumption rate BSFC (fuel consumption per unit output [g / kwh]) decreases. This is due to a reduction in pumping loss and an improvement in combustion efficiency. When the engine output PENG increases and approaches the bottom output PEBB, the slope of the curve shown in FIG. 5A (absolute value of the negative slope) decreases, that is, the fuel efficiency improvement effect by applying the engine output PENG to power generation Therefore, as shown in FIG. 4, it is desirable that a region below the curve L2 that is lower than the BSFC bottom line L1 by the margin load PEPLS is a margin load operation region RLLD.

  FIG. 5B shows the engine output PENG when the engine speed NE is constant, and the fuel consumption amount GFC per unit time when high-voltage power generation (power generation at the third voltage V3) is performed by the generator 1. g / h]. As is apparent from this figure, the lower the engine output PENG (load), the smaller the fuel consumption amount GFC. Therefore, the curve L2 shown in FIG. 4 is set in correspondence with the broken line L4 shown in FIG. 5B to suppress the fuel consumption amount GFC when the high voltage power generation is executed.

  In addition, since the stable running state is continued as one of the conditions for allowing the surplus load power generation through steps S23 to S25 in FIG. 3, the frequency of changing the power generation voltage in a state where the variation of the accelerator pedal operation amount AP is large. It is possible to prevent harmful effects such as flickering of light due to increase.

  FIG. 6 is a time chart for explaining the control operation by the processing of FIG. 3. The vehicle speed VP, the accelerator pedal operation amount AP (solid line), the smoothed accelerator pedal operation amount APAV (broken line), the difference DAP, and the margin load The transition of the power generation flag FLLD is shown.

  In this operation example, the accelerator pedal operation amount AP fluctuates before time t21, and the stable running state does not continue for the predetermined stabilization time TSTB. From time t21, the accelerator pedal operation amount AP is maintained substantially constant, and the operation state of the engine 2 shifts to the surplus load operation region RLLD. At time t22, the difference DAP becomes equal to or less than the determination threshold value DAPTH, the stable running state continues for a predetermined stabilization time TSTB, and the margin load power generation flag FLLD is set to “1” at time t23. The accelerator pedal is returned at time t24, and the surplus load power generation flag FLLD is returned to “0”.

  FIG. 7 is a time chart for explaining the control operation by the processing of FIG. 2. The battery power integrated value IBSUM, the vehicle speed VP, the fuel cut flag FFC, and the regenerative power generation set to “1” when the regenerative power generation is executed. The transition of the flag FREG, the margin load power generation flag FLLD, the low voltage power generation flag FLVG set to “1” when executing low voltage power generation, and the power generation voltage VACG is shown.

  At time t1, the battery current integrated value IBSUM is “0” (reference charge state), and then the vehicle starts and accelerates. Until time t2, normal power generation (power generation voltage V2) is performed, and control is performed so that power is generated by the amount used for the electric load 10. This control is called “zero balance control”, and the battery charge amount is maintained almost constant.

  Deceleration is started from time t2, and fuel cut operation is started. Since IBSUM <α at time t2 (at the start of fuel cut operation), high voltage power generation at the third voltage V3 is started. Deceleration ends at time t3, after which the vehicle stops and the engine 2 enters an idle state. In this state, low voltage power generation at the first voltage V1 is executed. Since the first voltage V1 is lower than the reference battery output voltage VB0, power is generated, but the battery 4 is not charged. Therefore, battery current integrated value IBSUM decreases. When the battery current integrated value IBSUM reaches “0” (time t4), the flow shifts to zero balance control (normal power generation). When the vehicle is accelerated from time t4 and the surplus load power generation flag FLLD is set to “1” at time t5, the process shifts to high voltage power generation (margin load power generation).

  At time t6, the accelerator pedal is depressed, and the surplus load power generation flag FLLD is returned to “0”. At this time, since the battery current integrated value IBSUM is larger than “0”, the process proceeds to low voltage power generation. When the fuel cut operation is started from time t7, since IBSUM> α at the start time, the process proceeds to regenerative power generation. At time t8, the fuel cut operation ends, the idling stop state is entered, and power generation is interrupted. Therefore, the battery current integrated value IBSUM decreases to a negative value.

  At time t9, the engine is restarted and the vehicle starts. Since the battery current integrated value IBSUM is smaller than “0”, high voltage power generation is performed. At time t10, the battery current integrated value IBSUM reaches “0” and shifts to normal power generation.

  As described above, in the present embodiment, whether or not the battery current integrated value IBSUM indicating the charge amount of the battery is greater than the predetermined threshold value α at the start time (t2, t7) of the fuel cut operation in which the fuel supply to the engine 2 is stopped. When the battery current integrated value IBSUM is less than or equal to the predetermined threshold value α, high voltage power generation is performed in which the generator 1 generates power at the third voltage V3 higher than the reference battery output voltage VB0, and the battery current integrated value IBSUM is Is larger than the predetermined threshold value α, regenerative power generation is performed to generate power at a fourth voltage V4 higher than the third voltage V3. In general, the higher the SOC, the more difficult the battery is charged, so the amount of power charged in the battery 4 is reduced. Therefore, either high voltage power generation (V3) or regenerative power generation (V4) is selected according to the charge amount of the battery at the start of fuel cut operation, and regenerative power generation is performed only when the charge amount of the battery 4 is large. By executing, while maintaining the charge amount of the battery 4 optimally, the temperature rise of the generator-related device can be suppressed and the life can be extended. In addition, when the battery current integrated value IBSUM is equal to or less than the predetermined threshold α at the start of the fuel cut operation, the battery current integrated value IBSUM is not shifted to the regenerative power generation even if the battery current integrated value IBSUM exceeds the predetermined threshold α after the fuel cut operation starts The execution frequency of regenerative power generation can be suppressed, and the life extension effect of the battery 4 can be enhanced.

  Further, in a predetermined operation state in which the engine 2 outputs a positive torque, that is, in an operation state in which the surplus load power generation flag FLLD is “1”, high voltage power generation that generates power with the third voltage V3 higher than the reference battery output voltage VB0 is performed. The surplus load power generation flag FLLD is set to “1” when the output PENG (load) of the engine 2 is lower than the bottom line (FIG. 4, L1) of the net fuel consumption rate. Since the engine operating state can be brought close to the bottom line of the net fuel consumption rate by applying a power generation load by the generator 1, it is necessary to generate power in another operating region where the amount of fuel consumed for power generation is large Can be reduced, and fuel consumption (electricity cost) can be improved.

  Further, a stable running state in which the difference DAP, which is the absolute value of the difference between the smoothed accelerator pedal operation amount APAV, which is the moving average value of the detected accelerator pedal operation amount AP, and the accelerator pedal operation amount AP, is equal to or less than the determination threshold DAPTH is predetermined. Since the surplus load power generation flag FLLD is set to “1” when the stabilization time TSTB continues, the flickering of the light due to the increase in the frequency of changing the power generation voltage while the fluctuation of the accelerator pedal operation amount AP is large It is possible to prevent harmful effects.

Also, the input / output current value IB of the battery 4 is acquired by the battery sensor 21, and the integration of the acquired current value IB is a value when the battery 4 is in the reference charging state (SOC is in the range of 75 to 90%). Is executed as the initial value (“0”), the battery current integrated value IBSUM indicating the charge amount of the battery 4 is calculated. Therefore, it is possible to obtain an accurate charge amount and accurately control the generated voltage.
In the present embodiment, the ECU 5 constitutes the generated voltage control means.

[Second Embodiment]
In the present embodiment, the battery output voltage VB is acquired by the battery sensor 21, the internal resistance value RI of the battery 4 is calculated using the battery output voltage VB and the battery current value IB, and the internal resistance value RI is equal to or greater than the predetermined resistance value RITH. When it is, regenerative power generation (V4) is prohibited. Except for the points described below, the second embodiment is the same as the first embodiment.

The internal resistance value RI is calculated by other processing (not shown) executed by the ECU 5. Specifically, the battery output voltage VB and the battery current value IB acquired by the battery sensor 21 during cranking of the engine 2 (when the starter motor is driven by power from the battery 4) are expressed by the following equation (11). Is applied to and stored in the memory. The calculation of the internal resistance value RI is not limited to during cranking, but may be performed while the battery 4 is being charged.
RI = | (VB0−VB) / IB | (11)
Here, VB0 is a battery output voltage when the battery current value IB is “0”.

FIG. 8 is a flowchart of the generated voltage control process in this embodiment. The process of FIG. 8 is obtained by adding steps S16a and S16b to the process of FIG.
In step S16a, the calculated internal resistance value RI is read. In step S16b, it is determined whether or not the internal resistance value RI is equal to or greater than a predetermined resistance value RITH. If the answer is affirmative (YES), the process proceeds to step S19, and high-voltage power generation is performed, while the answer to step S16b is negative (NO) and the internal resistance value RI is smaller than the predetermined resistance value RITH. Advances to step S20 to execute regenerative power generation.

As described above, in this embodiment, when the internal resistance value RI of the battery 4 is calculated using the equation (11) and the internal resistance value RI is equal to or greater than the predetermined resistance value RITH, regenerative power generation (V4) is prohibited. Is done. When regenerative power generation is performed, the value of the current flowing into the battery 4 increases, the SOC fluctuation range of the battery 4 increases, and the deterioration of the battery 4 may be promoted. Further, since the internal resistance value RI increases as the deterioration of the battery 4 progresses, the battery deterioration is prevented from being promoted by prohibiting regenerative power generation when the internal resistance value RI is equal to or greater than the predetermined resistance value RITH. can do.
In the present embodiment, the arithmetic processing using the expression (11) executed by the battery sensor 21 and the ECU 5 corresponds to the internal resistance value detecting means.

[Third Embodiment]
In this embodiment, the battery sensor 21 is disposed in the vicinity of the battery 4, and a temperature sensor for detecting the temperature TPT of a component (for example, a circuit wiring board) in the battery sensor 21 is provided in the battery sensor 21, and the detected component Based on the temperature TPT, the internal temperature TB of the battery 4 is estimated, and when the estimated internal temperature TB is equal to or higher than the predetermined temperature TBTH, regenerative power generation is prohibited. Except for the points described below, the second embodiment is the same as the first embodiment.

FIG. 9 is a flowchart of the generated voltage control process in the present embodiment. The process of FIG. 9 is obtained by adding steps S16c and S16d to the process of FIG.
In step S16c, the internal temperature TB of the battery 4 is estimated based on the detected component temperature TPT. Specifically, a TB table indicating the correlation between the component temperature TPT and the internal temperature TB is set in advance, and the internal temperature TB is estimated by searching the TB table according to the detected component temperature TPT.

  In step S16d, it is determined whether or not the internal temperature TB is equal to or higher than a predetermined temperature TBTH. When the answer is affirmative (YES), the process proceeds to step S19, and high voltage power generation is performed. On the other hand, when the answer to step S16d is negative (NO) and the internal temperature TB is lower than the predetermined temperature TBTH, Proceeding to step S20, regenerative power generation is executed.

As described above, in the present embodiment, the internal temperature TB of the battery 4 is estimated using the battery sensor 21, and regenerative power generation is prohibited when the estimated internal temperature TB is equal to or higher than the predetermined temperature TBTH. When the internal temperature TB of the battery 4 increases, the current value flowing into the battery tends to increase even if the charging voltage (generated voltage) is the same, and the battery 4 may be overcharged to promote deterioration. . By arranging the battery sensor 21 in the vicinity of the battery 4, it is possible to estimate the internal temperature TB of the battery from the component temperature TPT of the battery sensor 21. Therefore, it is possible to prevent battery deterioration from being promoted by prohibiting regenerative power generation when the estimated internal temperature TB is equal to or higher than the predetermined temperature TBTH.
In the present embodiment, the temperature sensor provided in the battery sensor 21 and step S16c in FIG. 9 correspond to the internal temperature estimating means.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the above-described embodiment, the “predetermined operation state” is the most preferable example in which the margin load power generation flag FLLD is set to “1”. However, the engine load (engine output) is from the BSFC bottom line. If the condition that the driving state is low is satisfied, charging using a surplus load is possible, so the “predetermined driving state” may be set as such an operating state.

  Further, although the engine output PENG has been described as a parameter indicating the load of the engine 2, the accelerator pedal operation amount AP or the opening degree of the throttle valve 6 may be used.

  The internal temperature TB of the battery 4 may be estimated based on the temperature detected by the temperature sensor attached to the battery 4 itself.

DESCRIPTION OF SYMBOLS 1 Generator 2 Internal combustion engine 4 Battery 5 Electronic control unit (Power generation voltage control means, internal resistance value detection means, internal temperature estimation means)
21 Battery sensor (internal resistance value detection means, internal temperature estimation means)
Accelerator sensor

Claims (7)

A generator control device that is mounted on a vehicle including an internal combustion engine, a generator driven by the engine, and a battery that can be charged by the electric power generated by the generator, and controls the generator,
A battery sensor attached to the battery for acquiring the state of the battery;
Power generation voltage control means for changing the power generation voltage of the generator according to the state of the vehicle,
The generated voltage control means determines whether or not the charge amount of the battery is larger than a predetermined charge amount using an output value of the battery sensor at a start time of a fuel cut operation for stopping fuel supply to the engine. When the charge amount is less than or equal to the predetermined charge amount, the generator performs high voltage power generation with a first high voltage higher than the output voltage of the battery, and the charge amount is greater than the predetermined charge amount In some cases, the generator control device performs regenerative power generation in which the power generator generates power at a second high voltage higher than the first high voltage.   The power generation voltage control means executes the high voltage power generation in a predetermined operation state where the engine outputs a positive torque, and the predetermined operation state includes a load of the engine and a net fuel consumption rate of the engine. The generator control device according to claim 1, wherein the generator control device is in a state lower than the lowest load. An accelerator sensor for detecting an operation amount of an accelerator pedal provided in the vehicle;
The generator according to claim 2, wherein the predetermined operation state is a stable running state in which a difference between a moving average value of the detected accelerator pedal operation amount and the accelerator pedal operation amount is a predetermined value or less. Control device.   The generator control device according to claim 3, wherein the predetermined operation state is a state in which the stable running state continues for a predetermined time.   The battery sensor acquires an input / output current value of the battery, and the generated voltage control means calculates the charge amount by executing integration of the acquired current value from a preset initial value. The generator control device according to any one of claims 1 to 4, wherein:   The generated voltage control means includes an internal resistance value detecting means for detecting an internal resistance value of the battery using the battery sensor, and prohibits the regenerative power generation when the internal resistance value is equal to or greater than a predetermined resistance value. The generator control device according to any one of claims 1 to 5, wherein:   6. The power generation voltage control means includes an internal temperature estimation means for estimating an internal temperature of the battery, and prohibits the regenerative power generation when the internal temperature is equal to or higher than a predetermined temperature. The generator control device according to any one of the above.

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