TWI784695B - Multi-input converter - Google Patents

Abstract

A multi-input converter includes a multi-input converter circuit and a control unit and is adapted to a load or a third DC voltage. The control unit generates a first control signal to a six control signals to make the multi-input converter circuit operate as a buck converter, a buck-boost converter, or a boost converter, so that at least one of a first DC voltage and a second DC voltage charges the load, or the first DC voltage to the second DC voltage, or the first DC voltage to the second DC voltage and the load, or the third DC voltage to at least one of the first DC voltage and the second DC voltage reverse charging based on the first DC voltage, a first DC current, the second DC voltage, a second DC current, a cross voltage of a capacitor, and a third DC current.

Description

Multiple Input Converter

The present invention relates to a multi-input converter, in particular to a multi-input converter providing multiple energy transfer modes between power sources and loads.

The development and application of multiple renewable energy sources is a new growing trend. However, when considering different renewable energy sources, such as photovoltaic (PV) and wind energy, these energies generally have a disadvantage, that is, considering that sometimes the sun will be shaded or sometimes there will be no wind, which will cause intermittent power supply, And can not continue to provide stable power supply. In order to solve this phenomenon, other auxiliary power sources are often required to provide energy to the load when solar or wind power cannot be supplied. Therefore, how to effectively manage the operation of these power sources has become a problem to be solved.

Therefore, the purpose of the present invention is to provide a multi-input converter with multiple energy transfer modes between power sources and loads.

Therefore, the present invention provides a multi-input converter suitable for a first straight DC voltage, a second DC voltage, and a load or a third DC voltage, and includes a multi-input converter circuit and a control unit. The multi-input converter circuit includes a first power switch to a fourth power switch, an inductor, a fifth switch, a sixth switch, and a capacitor.

The first power switch includes a first terminal, a second terminal, and a control terminal receiving a first control signal. The second power switch includes a first end electrically connected to the second end of the first power switch, a second end, and a control end receiving a second control signal, the first end of the first power switch and the second terminal of the second power switch receives the cross-voltage of the first DC voltage. The third power switch includes a first terminal, a second terminal electrically connected to the second terminal of the second power switch, and a control terminal for receiving a third control signal. The fourth power switch includes a first terminal electrically connected to the second terminal of the third power switch, a second terminal, and a control terminal receiving a fourth control signal. The inductor includes a first end electrically connected to the second end of the first power switch, and a second end. The first terminal of the third power switch and the second terminal of the inductor receive a voltage across the second DC voltage.

The fifth switching switch includes a first end electrically connected to the first end of the first power switch, a second end electrically connected to the second end of the inductor, and a control end receiving a fifth control signal . The sixth switching switch includes a first end electrically connected to the second end of the inductor, a second end, and a control end receiving a sixth control signal. the capacitor includes a first end electrically connected to the second end of the sixth switch, and the second end electrically connected to the second end of the fourth power switch, and connected in parallel with the load or receiving the third DC voltage.

The control unit is based on the first DC voltage, a first DC current flowing from the first terminal of the first power switch to the second terminal, the second DC voltage, and the first terminal of the third power switch. A second DC current flowing to the second terminal, a voltage across the first terminal and the second terminal of the capacitor, and a third DC current flowing through the load or the third DC voltage generate the first control signal to the sixth control signal, so that the multi-input converter circuit operates as a buck (Buck) converter, a buck-boost (Buck-boost) converter, or a boost (Boost) converter, to The load is charged by at least one of the first DC voltage and the second DC voltage, or the second DC voltage or the load is charged by the first DC voltage, or the load is charged by the third DC voltage. At least one of the first DC voltage and the second DC voltage is reversely charged.

In some implementation aspects, the capacitor is connected in parallel with the load. When the control unit operates in a first situation, the generated third control signal controls the third power switch to be non-conductive, and the fourth control signal controls the fourth power switch to be conductive, and the fifth control signal controls The fifth switch is not turned on, and the sixth control signal controls the sixth switch to be turned on, and the control unit In a first interval of each predetermined period, the first power switch is controlled to be turned on and the second power switch is not turned on by the first control signal and the second control signal, and each of the In a second interval of a predetermined period, the first power switch is controlled by the first control signal and the second control signal to be turned off and the second power switch is turned on, so that the multi-input converter circuit operates as the step-down The converter is used to charge the load by the first DC voltage.

In some other implementation aspects, the capacitor is connected in parallel with the load. When the control unit operates in a second situation, the generated first control signal controls the first power switch to be non-conductive, and the second control signal controls the second power switch to be conductive, and the fifth control signal controls The fifth switching switch is not turned on, and the control unit is based on the second DC voltage, the second DC current, the DC output voltage, and the third DC current in a first interval of each predetermined period, through the The third control signal, the fourth control signal, and the sixth control signal respectively control the third power switch to be turned on, the fourth power switch to be turned off, and the sixth switch to be turned off, and each predetermined cycle In a second interval, the third control signal, the fourth control signal, and the sixth control signal respectively control the third power switch to be non-conductive, the fourth power switch to be conductive, and the sixth switch to be conductive , so that the multi-input converter circuit operates as the buck-boost converter to charge the load from the second DC voltage.

In some other implementation aspects, the capacitor is connected in parallel with the load. When the control unit operates in a third situation, the generated fifth control signal controls the fifth switch to be non-conductive, and the control unit controls the fifth switch according to the first DC voltage, the first DC current, and the second DC voltage, the second direct current, the direct output voltage, and the third direct current controls the conduction of the first power switch and the conduction of the second power switch through the first control signal to the fourth control signal and the sixth control signal in a first interval of each predetermined period. non-conducting, the third power switch is conducting, the fourth power switch is not conducting, and the sixth switching switch is not conducting, and in a second interval of each predetermined period, the first control signal is used to communicate with the first power switch The four control signals and the sixth control signal respectively control the first power switch to be turned on, the second power switch to be turned off, the third power switch to be turned off, the fourth power switch to be turned on, and the sixth switch to be turned on, and In a third interval of each predetermined period, the first power switch is controlled to be non-conductive, the second power switch is conductive, and the first power switch is respectively controlled by the first control signal to the fourth control signal and the sixth control signal. The three power switches are not conducting, the fourth power switch is conducting, and the sixth switching switch is conducting, so that the multi-input converter circuit operates as the buck-boost converter to convert the first DC voltage and the second DC voltage. voltage to charge the load.

In some other implementation aspects, when the control unit operates in a fourth situation, the generated first control signal controls the first power switch to be non-conductive, and the second control signal controls the second power switch The switch is turned on, and the fourth control signal controls the fourth power switch not to be turned on, and the sixth control signal controls the sixth switch to be turned off, and the control unit according to the first DC voltage, the first DC current, The second DC voltage and the second DC current control the third power switch through the third control signal and the fifth control signal respectively in a first interval of each predetermined period not conducting and the fifth switching switch is conducting, and in a second interval of each predetermined period, the third control signal and the fifth control signal are used to control the third power switch to conduct and the fifth switching switch respectively is non-conductive, so that the multi-input converter circuit operates as the buck-boost converter to charge the second DC voltage from the first DC voltage.

In other embodiments, wherein the capacitor is connected in parallel with the load, when the control unit operates in a fifth situation, the control unit according to the first DC voltage, the first DC current, the DC output voltage , and the third direct current is in a first interval of each predetermined period, and the first power switch is controlled to be turned on, the second power switch is not turned on, and the second power switch is controlled by the first control signal to the sixth control signal respectively. The three power switches are not conducting, the fourth power switch is conducting, the fifth switching switch is not conducting, and the sixth switching switch is conducting, and in a second interval of each predetermined period, the first control signal to The sixth control signal respectively controls the first power switch to be off, the second power switch to be on, the third power switch to be off, the fourth power switch to be on, the fifth switch to be off, and the sixth switch to be off. The switch is turned on so that the multi-input converter circuit operates as the buck converter to charge the load by the first DC voltage.

When the control unit is operating in the fifth situation, the control unit uses the first DC voltage, the second DC voltage, and the second DC current in a third interval of each predetermined period, through the first A control signal to the sixth control signal respectively control the first power switch to be non-conductive, the second power switch to be conductive, and the third power switch to be non-conducting, the fourth power switch is non-conducting, the fifth switching switch is conducting, and the sixth switching switch is non-conducting, and in a fourth interval of each predetermined cycle, the first control signal is used to The six control signals respectively control the first power switch to be off, the second power switch to be on, the third power switch to be on, the fourth power switch to be off, the fifth switch to be off, and the sixth switch to be off. is turned on so that the multi-input converter circuit operates as the buck-boost converter to charge the second DC voltage from the first DC voltage.

In some other implementation aspects, the capacitor receives the third DC voltage. When the control unit operates in a sixth situation, the generated third control signal controls the third power switch to be non-conductive, and the fourth control signal controls the fourth power switch to be conductive, and the fifth control signal controls The fifth switch is not turned on, and the sixth control signal controls the sixth switch to be turned on, and the control unit according to the first DC voltage, the first DC current, the third DC voltage and the third DC The current is in a first interval of each predetermined period, and the first power switch is controlled by the first control signal and the second control signal to be turned off and the second power switch is turned on, and in each predetermined period a second interval, the first control signal and the second control signal respectively control the first power switch to conduct and the second power switch to not conduct, so that the multi-input converter circuit operates as the boost converter, The first DC voltage is charged by the third DC voltage.

In some other implementation aspects, wherein, the capacitor receives the third direct flow voltage. When the control unit operates in a seventh situation, the generated first control signal controls the first power switch to be non-conductive, and the second control signal controls the second power switch to be conductive, and the fifth control signal controls The fifth power switch is not turned on, and the control unit is based on the second DC voltage, the second DC current, the third DC voltage, and the third DC current in a first interval of each predetermined period, by The third control signal, the fourth control signal, and the sixth control signal respectively control the third power switch to be off, the fourth power switch to be on, and the sixth switch to be on, and each predetermined cycle In a second interval, the third control signal, the fourth control signal, and the sixth control signal respectively control the conduction of the third power switch, the non-conduction of the fourth power switch, and the non-conduction of the sixth switch is turned on so that the multi-input converter circuit operates as the buck-boost converter to charge the second DC voltage from the third DC voltage.

In some other implementation aspects, the capacitor receives the third DC voltage. When the control unit operates in an eighth situation, the generated fifth control signal controls the fifth power switch to be non-conductive, and the control unit according to the first DC voltage, the first DC current, and the second DC voltage, the second direct current, the third direct current voltage, and the third direct current in a first interval of each predetermined cycle, through the first control signal to the fourth control signal and the sixth control signal Respectively control the first power switch to be off, the second power switch to be on, the third power switch to be off, the fourth power switch to be on, and the sixth switch to be on, and each preset A second interval of a fixed period, through the first control signal to the fourth control signal and the sixth control signal to respectively control the first power switch to be turned on, the second power switch to be turned off, and the third power switch to be turned off conduction, the fourth power switch conduction, and the sixth switching switch conduction, and in a third interval of each predetermined period, the first control signal to the fourth control signal and the sixth control signal are respectively Controlling the first power switch to be off, the second power switch to be on, the third power switch to be on, the fourth power switch to be off, and the sixth switch to be off, so that the multi-input converter circuit operates on the first operating as the boost converter from the first section to the second section, and operating as the buck-boost converter in the third section, so as to charge the first DC voltage and the second DC voltage from the third DC voltage .

The efficacy of the present invention lies in: the first power switch to the fourth power switch, the fifth switching switch, and the sixth switching switch are controlled by the first control signal to the sixth control signal generated by the control unit conduction or non-conduction, so that the multi-input converter circuit operates as the buck converter, the buck-boost converter, or the boost converter, and realizes a multi-input converter with multiple power flow control (Multiple -input converter).

1: Control unit

91~93: first voltage source~third voltage source

Co: capacitor

d1~d4: duty cycle

Iin1~Iin2: the first DC current~the second DC current

IL: Inductor current

Iout: the third direct current

L: Inductor

M1~M4: the first power switch~the fourth power switch

M5~M6: the fifth switch ~ the sixth switch

Ro: load

S1~S6: the first control signal ~ the sixth control signal

Ts: scheduled cycle

t: time

Vin1~Vin2: the first DC voltage~the second DC voltage

VDC: the third DC voltage

VL: Inductance across voltage

Vout: DC output voltage

Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a circuit diagram illustrating an embodiment of the multi-input converter of the present invention; Fig. 2 is a circuit diagram illustrating a multi-input converter circuit of the embodiment operating in a first mode; Fig. 3 is a circuit diagram illustrating the multi-input converter circuit A multi-input converter circuit of the embodiment operates in a second mode; FIG. 4 is a circuit diagram illustrating that a multi-input converter circuit of the embodiment operates in a third mode; FIG. 5 is a circuit diagram illustrating the embodiment A multi-input converter circuit of the embodiment operates in a fourth mode; Fig. 6 is a circuit diagram illustrating that a multi-input converter circuit of the embodiment operates in a fifth mode; Fig. 7 is a circuit diagram illustrating a mode of the embodiment The multi-input converter circuit operates in a sixth mode; Fig. 8 is a circuit diagram illustrating that a multi-input converter circuit of this embodiment operates in a seventh mode; Fig. 9 is a circuit diagram illustrating a multi-input converter circuit of this embodiment The converter circuit operates in an eighth mode; FIG. 10 is a timing diagram illustrating the relationship between a plurality of signals of a third scenario of the embodiment; and FIG. 11 is a timing diagram illustrating a first situation of the embodiment One of the Multiple Signals of the Five Situations relationship between.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same numerals.

Referring to FIG. 1 , an embodiment of the multi-input converter of the present invention is suitable for a first voltage source 91 , a second voltage source 92 , and a load Ro, and includes a multi-input converter circuit and a control unit 1 . The multi-input converter circuit is electrically connected to the control unit 1, and includes a first power switch M1 to a fourth power switch M4, an inductor L, a fifth switch M5, a sixth switch M6, and a Capacitor Co. In this embodiment, the first power switch M1 to the fourth power switch M4, the fifth switch M5, and the sixth switch M6 are all wide bandgap devices, such as GaN high-speed electron mobility field effect transistors, but not limited thereto.

The first power switch M1 includes a first terminal electrically connected to a positive terminal of the first voltage source 91 , a second terminal, and a control terminal receiving a first control signal S1 . The second power switch M2 includes a first end electrically connected to the second end of the first power switch M1, a second end electrically connected to a negative end of the first voltage source 91, and receiving a second control signal A control terminal of S2. The first voltage source 91 outputs a first DC voltage Vin1 , that is, the first terminal of the first power switch M1 and the second terminal of the second power switch M2 receive a voltage across the first DC voltage Vin1 .

The third power switch M3 includes a first end electrically connected to a positive end of the second voltage source 92, a second end electrically connected to the second end of the second power switch M2, and receiving a third control signal A control terminal of S3. The fourth power switch M4 includes a first terminal electrically connected to the second terminal of the third power switch M3, a second terminal, and a control terminal receiving a fourth control signal S4. The inductor L includes a first terminal electrically connected to the second terminal of the first power switch M1, and a second terminal. The second voltage source 92 outputs a second DC voltage Vin2 , that is, the first terminal of the third power switch M3 and the second terminal of the inductor L receive a voltage across the second DC voltage Vin2 .

The fifth switch M5 includes a first end electrically connected to the first end of the first power switch M1, a second end electrically connected to the second end of the inductor L, and receiving a fifth control signal S5 a control terminal. The sixth switch M6 includes a first end electrically connected to the second end of the inductor L, a second end, and a control end receiving a sixth control signal S6. The capacitor Co includes a first end electrically connected to the second end of the sixth switch M6 and a second end electrically connected to the second end of the fourth power switch M4, and is connected in parallel with the load Ro.

The control unit 1 is based on the first DC voltage Vin1, a first DC current Iin1 flowing from the first end of the first power switch M1 to the second end, the second DC voltage Vin2, and the third power switch M1. A second direct current Iin2 flowing from the first terminal of M3 to the second terminal, a voltage across the first terminal and the second terminal of the capacitor Co (that is, a DC output voltage Vout), and a current flowing through the load Ro a third direct current Iout, generating the first control signal S1 to the sixth control signal S6, so that the multi-input converter circuit operates as a step-down (Buck) converter, a step-down step-up (Buck-boost) converter, or a A boost converter is used to charge the load Ro from at least one of the first DC voltage Vin1 and the second DC voltage Vin2, or to charge the load Ro from the first DC voltage Vin1 to the second DC voltage Vin2 or Charging the second DC voltage Vin2 and the load Ro.

In this embodiment, the multi-input converter circuit is detected in the prior art to obtain the first DC voltage Vin1, the first DC current Iin1, the second DC voltage Vin2, the second DC current Iin2, the DC The feedback circuits of multiple feedback signals such as the output voltage Vout and the third direct current Iout are omitted, and the driving capability of the first control signal S1 to the sixth control signal S6 generated by the control unit 1 is enhanced. The gate drive circuit is also omitted. The first DC voltage Vin1 is greater than the second DC voltage Vin2. The control unit 1 is, for example, a digital signal processor (DSP), such as TMS320F28379D, and includes an analog-to-digital converter (ADC), a proportional-integral controller (PI controller), and a pulse width modulation module (PWM module ). The analog-to-digital converter is used to convert the detected feedback signals (for example) into a plurality of digital signals, and the proportional-integral controller generates a plurality of control variables (such as a plurality of duty ratios) according to the digital signals ), the pulse width modulation module generates the first control signal S1 to the sixth control signal S6 corresponding to the duty ratios according to the control variables.

The multi-input converter circuit operates between a first mode to an eighth mode. Referring to FIG. 2 again, when the multi-input converter circuit operates in the first mode, the first output generated by the control unit 1 The control signal S1 to the sixth control signal S6 respectively control the first power switch M1 to be turned on, the second power switch M2 to be turned off, the third power switch M3 to be turned on, the fourth power switch M4 to be turned off, and the fifth power switch M4 to be turned off. The switching switch M5 is not conducting, and the sixth switching switch M6 is not conducting. Referring to FIG. 3 again, when the multi-input converter circuit operates in the second mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to be turned on. , the second power switch M2 is off, the third power switch M3 is off, the fourth power switch M4 is on, the fifth switch M5 is off, and the sixth switch M6 is on.

Referring to FIG. 4 again, when the multi-input converter circuit operates in the third mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to conduction, the second power switch M2 is on, the third power switch M3 is on, the fourth power switch M4 is off, the fifth switch M5 is off, and the sixth switch M6 is off. Referring to FIG. 5 again, when the multi-input converter circuit operates in the fourth mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to conduction, the second power switch M2 conduction, the third power switch M3 conduction, the fourth power switch M4 conduction, the fifth switch M5 conduction, and the The sixth switch M6 is turned on. Referring to FIG. 6 again, when the multi-input converter circuit operates in the fifth mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to On, the second power switch M2 is on, the third power switch M3 is off, the fourth power switch M4 is off, the fifth switch M5 is on, and the sixth switch M6 is off.

Referring to FIG. 1 and FIG. 7, in this embodiment, when the multi-input converter circuit operates between the sixth mode and the eighth mode, this embodiment is not applicable to the load Ro, but is applicable to a The third DC voltage source 93, and the capacitor Co is changed to receive a third DC voltage VDC of the third DC voltage source 93, then the control unit 1 is based on the first DC voltage Vin1, the first DC current Iin1, The second DC voltage Vin2, the second DC current Iin2, the voltage across the first terminal and the second terminal of the capacitor Co (that is, the third DC voltage VDC), and the voltage flowing through the third DC voltage VDC The third direct current Iout generates the first control signal S1 to the sixth control signal S6, so that the multi-input converter circuit operates as a step-up (Boost) converter or the buck-boost (Buck-boost) conversion The device is used to reversely charge at least one of the first DC voltage Vin1 and the second DC voltage Vin2 by the third DC voltage VDC.

Referring to FIG. 7 again, when the multi-input converter circuit operates in the sixth mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to conduction, the second power switch M2 conducts, the third power switch M3 does not conduct, the fourth power switch M4 conducts, the fifth The switch M5 is not turned on, and the sixth switch M6 is turned on. Referring to FIG. 8 again, when the multi-input converter circuit operates in the seventh mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to be turned on. , the second power switch M2 is off, the third power switch M3 is off, the fourth power switch M4 is on, the fifth switch M5 is off, and the sixth switch M6 is on. Referring to FIG. 9 again, when the multi-input converter circuit operates in the eighth mode, the first control signal S1 to the sixth control signal S6 generated by the control unit 1 respectively control the first power switch M1 to conduction, the second power switch M2 is on, the third power switch M3 is on, the fourth power switch M4 is off, the fifth switch M5 is off, and the sixth switch M6 is off.

In more detail, the control unit 1 operates between a first situation to an eighth situation, referring to FIG. 1 , FIG. 3 , and FIG. 5 , when the control unit 1 operates in the first situation, the control unit 1 Controlling the multi-input converter circuit to operate in the The second mode, and in a second interval of each predetermined period, control the multi-input converter circuit to operate in the fourth mode, so that the multi-input converter circuit operates as the step-down converter, so as to be controlled by the first A DC voltage Vin1 charges the load Ro. The predetermined period is equal to the sum of the first interval and the second interval. The relationship between the DC output voltage Vout, the first DC voltage Vin1, and the duty cycle d1 of the first control signal S1 is as follows: Vout=d1*Vin1.

Referring to FIG. 1, FIG. 4, and FIG. 5, when the control unit 1 operates in the second situation, the control unit 1 according to the second DC voltage Vin2, the second DC current Iin2, the DC output voltage Vout, and The third direct current Iout controls the multi-input converter circuit to operate in the third mode during another first interval of each predetermined period, and controls the multi-input converter circuit to operate in the third mode during another second interval of each predetermined period. The input converter circuit operates in the fourth mode, so that the multi-input converter circuit operates as the buck-boost converter to charge the load Ro by the second DC voltage Vin2. The predetermined period is equal to the sum of the other first interval and the other second interval. The relationship among the DC output voltage Vout, the second DC voltage Vin2 and the duty cycle d1 of the third control signal S3 is Vout=d1*Vin2/(1−d1).

Referring to FIG. 1, FIG. 2, FIG. 3, and FIG. 5, when the control unit 1 operates in the third situation, the control unit 1 according to the first DC voltage Vin1, the first DC current Iin1, the second DC The voltage Vin2, the second DC current Iin2, the DC output voltage Vout, and the third DC current Iout control the multi-input converter circuit to operate in the first mode in another first interval of each predetermined cycle, And in another second interval of each predetermined period, control the multi-input converter circuit to operate in the second mode, and in a third interval of each predetermined period, control the multi-input converter circuit to operate in the In the fourth mode, the multi-input converter circuit is operated as the buck-boost converter, so that the negative voltage can be controlled by the first DC voltage Vin1 and the second DC voltage Vin2. Carry Ro charging. The predetermined period is equal to the sum of the other first interval to the third interval. Between the DC output voltage Vout, the first DC voltage Vin1, the second DC voltage Vin2, the duty cycle (d1+d2) of the first control signal S1, and the duty cycle d1 of the third control signal S3 The relationship is Vout=(d2*Vin1+d1*Vin2)/(1-d1).

Referring to FIG. 10 again, it illustrates that in the third situation, the first control signal S1, the third control signal S3, an inductance cross voltage VL of the first end and the second end of the inductor L, are determined by the Correspondence between an inductor current IL flowing from the first end of the inductor L to the second end, the first direct current Iin1 , and the second direct current Iin2 . Wherein, since the first DC voltage Vin1 is greater than the second DC voltage Vin2, the duty cycle (d1+d2) of the first control signal S1 is greater than the duty cycle d1 of the third control signal S3. The predetermined period is Ts, at time t between 0 and d1Ts, operating in the first mode, so that the first DC voltage Vin1 is connected in series with the second DC voltage Vin2 and stores energy in the inductor L, the load The energy required by Ro is provided by this capacitor Co. During the time t between d1Ts and d2Ts, operating in the second mode, the first DC voltage Vin1 stores energy in the inductor L and also charges the capacitor Co, and supplies energy to the load Ro. When the time t is between d2Ts and d3Ts, the operation is in the fourth mode, so that the first DC voltage Vin1 and the second DC voltage Vin2 are not powered due to the open circuit, and the inductor L supplies the load terminal Capacitor Co supplies energy with this load Ro.

Referring to Fig. 1, Fig. 4, and Fig. 6, when the control unit 1 operates in the fourth situation environment, the control unit 1 controls the first interval of each predetermined period according to the first DC voltage Vin1, the first DC current Iin1, the second DC voltage Vin2, and the second DC current Iin2. The multi-input converter circuit operates in the fifth mode, and in another second interval of each predetermined period, the multi-input converter circuit is controlled to operate in the third mode, so that the multi-input converter circuit operates as the The buck-boost converter is used to charge the second DC voltage Vin2 by the first DC voltage Vin1. The predetermined period is equal to the sum of the other first interval and the other second interval. The relationship among the second DC voltage Vin2 , the first DC voltage Vin1 , and the duty cycle d1 of the fifth control signal S5 is Vin2=d1*Vin1/(1−d1).

Referring to FIG. 1, FIG. 3 to FIG. 6, when the control unit 1 operates in the fifth situation, the control unit 1 according to the first DC voltage Vin1, the first DC current Iin1, the DC output voltage Vout, and The third direct current Iout controls the multi-input converter circuit to operate in the second mode during another first interval of each predetermined period, and controls the multi-input converter circuit to operate in the second mode during another second interval of each predetermined period. The converter circuit operates in the fourth mode, and controls the multi-input according to the first DC voltage Vin1, the second DC voltage Vin2, and the second DC current Iin2 in another third interval of each predetermined period. The converter circuit operates in the fifth mode, and controls the multi-input converter circuit to operate in the third mode in a fourth interval of each predetermined period, so that the multi-input converter circuit operates in the other first interval and the other second interval, it operates as the step-down converter to charge the load Ro with the first DC voltage Vin1 and operate as the buck-boost converter in the other third interval and the fourth interval, so as to charge the second direct current voltage Vin2 by the first direct current voltage Vin1. The predetermined period is equal to the sum of the other first interval to the fourth interval. The first DC voltage Vin1, the second DC voltage Vin2, the DC output voltage Vout, the duty cycle d1 of the first control signal S1, the duty cycle d4 of the third control signal S3, the fourth control signal S4 The relationship between the duty cycle (d1+d2) of the fifth control signal S5 and the duty cycle d3 of the fifth control signal S5 is Vin1=[(d1+d2)*Vout−d4*Vin2]/(d1−d3).

Referring to FIG. 11 again, the corresponding relationship between the first control signal S1 , the third control signal S3 to the fifth control signal S5 , and the inductor voltage VL is illustrated in the fifth situation. The predetermined period is Ts. When the time t is between 0 and d1Ts, the operation is in the second mode, so that the first DC voltage Vin1 stores energy on the inductor L, and the inductor current IL flows to the load Ro. During time t between d1Ts and d2Ts, operating in the fourth mode, the inductor L is discharged, the inductor current IL flows to the load Ro, and provides energy to the load Ro. During time t between d2Ts and d3Ts, operating in the fifth mode enables the first DC voltage Vin1 to store energy on the inductor L and commutates the inductor current IL. During the time t between d3Ts and d4Ts, operating in the third mode, the inductor L is discharged, and the inductor current IL flows to the second DC voltage Vin2 to provide energy to the second DC voltage Vin2.

Referring to FIG. 1, FIG. 7, and FIG. 8, when the control unit 1 operates in the sixth situation, the control unit 1 according to the first DC voltage Vin1, the first DC current Iin1, the third direct current voltage VDC, and the third direct current Iout control the multi-input converter circuit to operate in the sixth mode during each predetermined cycle in another first interval, and in each predetermined cycle In another second interval, the multi-input converter circuit is controlled to operate in the seventh mode, so that the multi-input converter circuit operates as the boost converter to convert the first direct voltage Vin1 from the third direct current voltage VDC to the first direct current voltage Vin1 Charge. The predetermined period is equal to the sum of the other first interval and the other second interval. The relationship among the first DC voltage Vin1 , the third DC voltage VDC, and the duty ratio d1 of the second control signal S2 is Vin1 =VDC/d1 .

1, FIG. 7, and FIG. 9, when the control unit 1 operates in the seventh situation, the control unit 1 according to the second DC voltage Vin2, the second DC current Iin2, the third DC voltage VDC, And the third direct current Iout controls the multi-input converter circuit to operate in the sixth mode in another first interval of each predetermined period, and controls the multi-input converter circuit to operate in the sixth mode in another second interval of each predetermined period. The input converter circuit operates in the eighth mode, so that the multi-input converter circuit operates as the buck-boost converter to charge the second DC voltage Vin2 from the third DC voltage VDC. The predetermined period is equal to the sum of the other first interval and the other second interval. The relationship between the second DC voltage Vin2 , the third DC voltage VDC, and the duty ratio d1 of the fourth control signal S4 is Vin2 = (1−d1 )*VDC/d1 .

1, 7 to 9, when the control unit 1 operates in the eighth situation, the control unit 1 according to the first DC voltage Vin1, the first DC current Iin1, the second DC voltage Vin2, the second DC current Iin2, the DC output voltage VDC, and the third DC current Iout control the operation of the multi-input converter circuit in another first interval of each predetermined period. In the sixth mode, and in another second interval of each predetermined period, control the multi-input converter circuit to operate in the seventh mode, and in a third interval of each predetermined period, control the multi-input converter circuit The input converter circuit operates in the eighth mode, so that the multi-input converter circuit operates as the boost converter in the other first interval to the another second interval, and operates as the buck converter in the third interval The boost converter is used to charge the first DC voltage Vin1 and the second DC voltage Vin2 by the third DC voltage VDC. The predetermined period is equal to the sum of the other first interval to the third interval. The third DC voltage VDC, the first DC voltage Vin1, the second DC voltage Vin2, the duty ratio d3 of the third control signal S3, and the duty ratio (d1+d2) of the fourth control signal S4 The relationship between VDC=(d1*Vin1+d3*Vin2)/(1-d3).

It can be seen from the aforementioned first situation to the eighth situation that the control unit 1 according to the first DC voltage Vin1, the first DC current Iin1, the second DC voltage Vin2, the second DC current Iin2, the capacitor Co The voltage across the first terminal and the second terminal, and the third DC current Iout flowing through the load Ro or the third DC voltage source 93 generate the first control signal S1 to the sixth control signal S6, making the multi-input converter circuit operate as the buck converter, the buck-boost converter, or the boost converter, so that the difference between the first DC voltage Vin1 and the second DC voltage Vin2 At least one of them charges the load Ro, or charges the second DC voltage Vin2 by the first DC voltage Vin1 or also charges the load Ro, or charges the first DC voltage Vin1 and the first DC voltage Vin1 by the third DC voltage VDC. At least one of the second DC voltages Vin2 is reversely charged.

In addition, it should be noted that: for example, the first voltage source 91 is a renewable energy source, the second voltage source 92 is a battery, and the multi-input converter can detect the first direct current of the renewable energy source respectively. The voltage Vin1, the second DC voltage Vin2 of the battery, and the voltage and current of the load Ro are used to know the current status of each power supply and load, and then adjust a suitable operating situation. For example: when operating in the first situation, the energy demanded by the load Ro is greater than the energy provided by the first DC voltage Vin1, then by switching to operate in the third situation, the first DC voltage Vin1 and the second DC voltage Vin2 provide energy to the load Ro at the same time, so as to achieve a balance between supply and demand of system energy.

To sum up, the present invention provides a simpler design than the conventional multiple independent converters, and greatly reduces the cost and complexity of the system. Through the multi-input converter, the input power of two input power sources can be transmitted to the load at the same time. In addition, when one of the input power sources fails or needs to be charged, any one of the two different input power sources can be independently transmitted to the load or supplied to the other input power source. Therefore, the present invention can make the energy transfer between each power supply and load complement each other, and is suitable for combining various energy application architectures, so it can indeed achieve the purpose of the present invention Purpose.

But the above-mentioned ones are only embodiments of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.

1: Control unit

91~93: first voltage source~third voltage source

Co: capacitor

Iin1~Iin2: the first DC current~the second DC current

IL: Inductor current

Iout: the third direct current

L: Inductor

M1~M4: the first power switch~the fourth power switch

M5~M6: the fifth switch ~ the sixth switch

Ro: load

S1~S6: the first control signal ~ the sixth control signal

Vin1~Vin2: the first DC voltage~the second DC voltage

VL: Inductance across voltage

Vout: DC output voltage

Claims (9)

A multi-input converter suitable for a first DC voltage, a second DC voltage, and a load or a third DC voltage, and comprising: a multi-input converter circuit comprising: a first power switch comprising a A first terminal, a second terminal, and a control terminal receiving a first control signal, a second power switch, including a first terminal electrically connected to the second terminal of the first power switch, a second terminal, and a control terminal receiving a second control signal, the first terminal of the first power switch and the second terminal of the second power switch receiving the cross-voltage of the first DC voltage, a third power switch comprising A first terminal, a second terminal electrically connected to the second terminal of the second power switch, and a control terminal for receiving a third control signal, a fourth power switch, including the terminal electrically connected to the third power switch A first end of the second end, a second end, and a control end receiving a fourth control signal, an inductor, including a first end electrically connected to the second end of the first power switch, and a first end Two terminals, the first terminal of the third power switch and the second terminal of the inductor receive the cross-voltage of the second DC voltage, a fifth switching switch, including the first terminal electrically connected to the first power switch A first end of the end, a second end electrically connected to the second end of the inductor, and a control end receiving a fifth control signal, a sixth switch, including the second end electrically connected to the inductor A first terminal, a second terminal, and a control terminal receiving a sixth control signal, and a capacitor, including a first terminal electrically connected to the second terminal of the sixth switching switch, and a first terminal electrically connected to the second terminal of the sixth switch. The second end of the second end of the four power switches is connected in parallel with the load or receives the third DC voltage; and a control unit flows from the first end of the first power switch to the first DC voltage according to the first DC voltage. A first direct current of the second terminal, the second direct current voltage, a second direct current flowing from the first terminal of the third power switch to the second terminal, the first terminal of the capacitor and the second The voltage across the terminal and a third direct current flowing through the load or the third direct voltage generate the first control signal to the sixth control signal, so that the multi-input converter circuit operates as a step-down (Buck) a converter, a Buck-boost converter, or a Boost converter, for charging the load by at least one of the first DC voltage and the second DC voltage, or The second DC voltage is charged by the first DC voltage, or the second DC voltage and the load are charged by the first DC voltage, or the first DC voltage and the second DC voltage are charged by the third DC voltage At least one of the voltages is reverse charged. The multi-input converter as claimed in claim 1, wherein the capacitor is connected in parallel with the load, and the voltage across the first terminal and the second terminal of the capacitor is equal to a DC output voltage, when the control unit operates at a first In one situation, the generated third control signal controls the third power switch to be non-conductive, and the fourth control signal controls the fourth power switch to be conductive, and the fifth control signal controlling the fifth switch to be non-conductive, and the sixth control signal to control the sixth switch to be conductive, and the control unit according to the first DC voltage, the first DC current, the DC output voltage, and the third DC The current is in a first interval of each predetermined period, and the first power switch is controlled to be turned on and the second power switch is not turned on by the first control signal and the second control signal respectively, and in each predetermined period a second interval, the first power switch is controlled by the first control signal and the second control signal to be turned off and the second power switch is turned on, so that the multi-input converter circuit operates as the step-down converter, The load is charged by the first DC voltage. The multi-input converter as claimed in claim 1, wherein the capacitor is connected in parallel with the load, and the voltage across the first terminal and the second terminal of the capacitor is equal to a DC output voltage, when the control unit operates at a first In the second situation, the generated first control signal controls the first power switch to be non-conductive, and the second control signal controls the second power switch to be conductive, and the fifth control signal controls the fifth switch to be non-conductive, And the control unit uses the third control signal, the fourth The control signal and the sixth control signal respectively control the conduction of the third power switch, the conduction of the fourth power switch, and the conduction of the sixth switch, and in a second interval of each predetermined period, by The third control signal, the fourth control signal, and the sixth control signal respectively control the third power switch to be off, the fourth power switch to be on, and the sixth switch to be on, so that the multi-input converter circuit operation for the step-down The boost converter is used to charge the load by the second DC voltage. The multi-input converter as claimed in claim 1, wherein the capacitor is connected in parallel with the load, and the voltage across the first terminal and the second terminal of the capacitor is equal to a DC output voltage, when the control unit operates at a first In three situations, the generated fifth control signal controls the fifth switch to be non-conductive, and the control unit according to the first DC voltage, the first DC current, the second DC voltage, the second DC current, The DC output voltage and the third DC current control the first power switch to be turned on, respectively controlled by the first control signal to the fourth control signal and the sixth control signal in a first interval of each predetermined period. The second power switch is off, the third power switch is on, the fourth power switch is off, and the sixth switch is off, and in a second interval of each predetermined period, by the first The control signal to the fourth control signal and the sixth control signal respectively control the first power switch to be turned on, the second power switch to be turned off, the third power switch to be turned off, the fourth power switch to be turned on, and the sixth power switch to be turned on. The switching switch is turned on, and in a third interval of each predetermined period, the first power switch is controlled to be non-conductive and the second power switch is controlled by the first control signal to the fourth control signal and the sixth control signal respectively. The switch is turned on, the third power switch is not turned on, the fourth power switch is turned on, and the sixth switch is turned on, so that the multi-input converter circuit operates as the buck-boost converter, so that the first DC voltage and charge the load with the second DC voltage. The multi-input converter as claimed in claim 1, wherein when the control unit operates in a fourth situation, the generated first control signal controls the first power switch to be non-conductive, and the second control signal controls The second power switch conduction, and the fourth control signal controls the fourth power switch to be non-conductive, and the sixth control signal controls the sixth switch to be non-conductive, and the control unit according to the first DC voltage, the first DC current, the The second DC voltage and the second DC current control the third power switch to be non-conductive and the fifth switching switch respectively by the third control signal and the fifth control signal in a first interval of each predetermined period. conduction, and in a second interval of each predetermined period, the third control signal and the fifth control signal respectively control the conduction of the third power switch and the non-conduction of the fifth switch, so that the multi-input conversion The converter circuit operates as the buck-boost converter to charge the second DC voltage from the first DC voltage. The multi-input converter as claimed in claim 1, wherein the capacitor is connected in parallel with the load, and the voltage across the first terminal and the second terminal of the capacitor is equal to a DC output voltage, when the control unit operates at a first In five situations, the control unit transmits the first control signal to The sixth control signal respectively controls the first power switch to be turned on, the second power switch to be turned off, the third power switch to be turned off, the fourth power switch to be turned on, the fifth switch to be turned off, and the sixth switch to be turned off. The switch is turned on, and in a second interval of each predetermined period, the first power switch is controlled to be off, the second power switch is turned on, and the third power switch is controlled by the first control signal to the sixth control signal respectively. The switch is not conducting, the fourth power switch is conducting, the fifth switching switch is not conducting, and the sixth switching switch is conducting, so that the multi-input converter circuit operates as the step-down converter to be controlled by the first DC voltage The load charges Electricity, when the control unit is operating in the fifth situation, the control unit is based on the first DC voltage, the second DC voltage, and the second DC current in a third interval of each predetermined period, by The first control signal to the sixth control signal respectively control the first power switch to be off, the second power switch to be on, the third power switch to be off, the fourth power switch to be off, and the fifth switch to be on , and the sixth switching switch is not conducting, and in a fourth interval of each predetermined period, the first power switch is controlled to be non-conducting and the second power switch is controlled by the first control signal to the sixth control signal respectively. switch conduction, the third power switch conduction, the fourth power switch non-conduction, the fifth switch non-conduction, and the sixth switch non-conduction, so that the multi-input converter circuit operates as the buck-boost conversion The device is used to charge the second DC voltage by the first DC voltage. The multi-input converter as claimed in item 1, wherein the capacitor receives the third DC voltage, and when the control unit operates in a sixth situation, the generated third control signal controls the third power switch not conducting, and the fourth control signal controls the fourth power switch to conduct, and the fifth control signal controls the fifth switch to not conduct, and the sixth control signal controls the sixth switch to conduct, and the control unit According to the first DC voltage, the first DC current, the third DC voltage, and the third DC current in a first interval of each predetermined cycle, the first control signal and the second control signal respectively controlling the first power switch to be off and the second power switch to be on, and in a second interval of each predetermined period, the first power switch is controlled by the first control signal and the second control signal respectively is turned off and the second power switch is not turned on, so that the multi-input converter circuit operates as the boost converter to charge the first DC voltage from the third DC voltage. The multi-input converter as claimed in claim 1, wherein the capacitor receives the third DC voltage, and when the control unit operates in a seventh situation, the first control signal generated controls the first power switch not conduct, and the second control signal controls the second power switch to conduct, and the fifth control signal controls the fifth power switch to not conduct, and the control unit according to the second DC voltage, the second DC current, the The third DC voltage and the third DC current are in a first interval of each predetermined period, and the third power switch is controlled by the third control signal, the fourth control signal, and the sixth control signal respectively. turn on, the fourth power switch is turned on, and the sixth switch is turned on, and in a second interval of each predetermined period, the third control signal, the fourth control signal, and the sixth control signal Respectively controlling the third power switch to be on, the fourth power switch to be off, and the sixth switch to be off, so that the multi-input converter circuit operates as the buck-boost converter, so that the third DC voltage The second DC voltage is charged. The multi-input converter as claimed in claim 1, wherein the capacitor receives the third DC voltage, and the voltage across the first terminal and the second terminal of the capacitor is equal to a DC output voltage, when the control unit operates at In an eighth situation, the generated fifth control signal controls the fifth power switch to be non-conductive, and the control unit according to the first DC voltage, the first DC current, the second DC voltage, the second DC current, the DC output voltage, and the third direct current controls the first power switch to be non-conductive and the second power switch to be non-conductive and the second power switch to be controlled respectively by the first control signal to the fourth control signal and the sixth control signal in a first interval of each predetermined period. The switch is turned on, the third power switch is not turned on, the fourth power switch is turned on, and the sixth switch is turned on, and in a second interval of each predetermined period, the first control signal to the fourth The control signal and the sixth control signal respectively control the first power switch to be turned on, the second power switch to be turned off, the third power switch to be turned off, the fourth power switch to be turned on, and the sixth switch to be turned on, and In a third interval of each predetermined period, the first power switch is controlled to be non-conductive, the second power switch is conductive, and the third power switch is controlled by the first control signal to the fourth control signal and the sixth control signal The power switch is turned on, the fourth power switch is not turned on, and the sixth switch is not turned on, so that the multi-input converter circuit operates as the boost converter from the first interval to the second interval, and in the third interval Interval operation is for the buck-boost converter to charge the first DC voltage and the second DC voltage by the third DC voltage.

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