A shunt circuit of a solar cell array and a spacecraft power supply system

Abstract

The utility model discloses a kind of shunt circuit of solar cell array and spacecraft power supply system.Solar cell array's shunt circuit includes: solar cell array, first power switch, second power switch, inverter and control drive module.Control drive module is connected with the control end of first power switch, control drive module generates drive signal, and first power switch is switched on or turned off according to drive signal;Control drive module is also connected with inverter, and inverter is connected with the control end of second power switch, and second power switch is switched on or turned off according to the inverting signal output by inverter, and inverting signal is opposite with drive signal.According to the technical scheme of the utility model, avoid the voltage backflow phenomenon of shunt circuit, reduce the heat consumption of the shunt circuit of control solar cell array, improve the energy conversion efficiency of solar cell array.

Description

Technical Field

[0001] This utility model relates to the field of satellite power technology, and in particular to a shunt circuit for a solar cell array and a spacecraft power supply system. Background Technology

[0002] As the primary energy supply device for spacecraft operating in orbit, the output performance of solar arrays directly affects the mission reliability and lifespan of the spacecraft. Due to the complex and variable space environment, factors such as sunlight intensity and temperature can affect the output voltage and power of solar arrays. When the output power exceeds the load demand, if not addressed promptly, it may lead to overvoltage damage to the solar array or instability in the power supply system. Therefore, configuring efficient and reliable shunt circuits for solar arrays is crucial. Their core function is to safely shunt excess output power, ensuring the output voltage of the solar array remains stable within a preset range and guaranteeing the normal operation of the load equipment.

[0003] Currently, solar cell arrays commonly employ Sequential Switching Shunt Regulation (S3R) technology. This technology divides the solar cell array into multiple independent cell modules, each module corresponding to a shunt switch and an isolation diode. Power is shunted by controlling the on / off state of the shunt switches. The isolation diode is a key component of the S3R circuit; its main function is to prevent voltage backflow between different cell modules or on the load side, while also providing electrical isolation when a specific module is not operating, ensuring the normal operation of other modules.

[0004] However, in practical applications, the reverse recovery characteristics of the diodes in the shunt circuit based on S3R technology are poor or the forward conduction threshold is limited, which cannot completely prevent voltage reverse current. The reverse current will cause irreversible damage to the solar cells and affect the overall performance of the battery array. On the other hand, the isolation diode is always in the forward conduction state when it is working normally, which will generate continuous conduction loss. Especially in high power supply scenarios, this loss will significantly increase the power consumption of the entire circuit and reduce energy utilization efficiency. Utility Model Content

[0005] This invention provides a shunt circuit for a solar cell array and a spacecraft power supply system, which avoids voltage backflow in the circuit, reduces the heat dissipation of the shunt circuit for controlling the solar cell array, and improves the energy conversion efficiency of the solar cell array.

[0006] According to one aspect of this utility model, a shunt circuit for a solar cell array is provided. The shunt circuit for the solar cell array includes: a solar cell array, a first power switch, a second power switch, an inverter, and a control drive module;

[0007] The positive terminal of the solar cell array is connected to the first terminal of the first power switch and the first terminal of the second power switch, respectively, and the negative terminal of the solar cell array is connected to the second terminal of the first power switch.

[0008] The second terminal of the second power switch is connected to the first terminal of the shunt circuit, and the negative terminal of the solar cell array is connected to the second terminal of the shunt circuit. The first and second terminals of the shunt circuit are used to connect to the bus or load.

[0009] The control drive module is connected to the control terminal of the first power switch. The control drive module is used to generate drive signals, and the first power switch is used to turn on or off according to the drive signals.

[0010] The control drive module is also connected to the first terminal of the inverter, and the second terminal of the inverter is connected to the control terminal of the second power switch. The second power switch is used to turn on or off according to the inverted signal output by the inverter. The inverted signal is inversely related to the drive signal.

[0011] Optionally, the first power switch includes a first transistor, the second power switch includes a second transistor, and the first transistor and the second transistor have the same channel type.

[0012] Optionally, the shunt circuit of the solar cell array also includes a control chip, one end of which is connected to the second terminal of the inverter, and the other end of which is connected to the control terminal of the second power switch, for driving the second power switch according to the inverted signal.

[0013] Optionally, the inverter includes a NOT gate.

[0014] Optionally, the control drive module includes: a signal generation unit and a signal enhancement unit;

[0015] The input terminal of the signal generation unit is connected to the voltage error signal, and the output terminal of the signal generation unit is connected to the input terminal of the signal enhancement unit. The signal generation unit is used to generate a control signal based on the voltage error signal. The voltage error signal is the error signal of the bus voltage between the first connection terminal and the second connection terminal of the shunt circuit.

[0016] The output of the signal enhancement unit serves as the output of the control drive module. The signal enhancement unit generates and outputs a drive signal based on the control signal, and the drive capability of the drive signal is greater than that of the control signal.

[0017] Optionally, the signal generation unit includes a triangular wave generator and a comparator;

[0018] The triangular wave generator is a PWM controller, which is used to output a reference waveform, which is a triangular wave.

[0019] The comparator has a first input port and a second input port. The PWM controller is connected to the first input port of the comparator, and the second input port of the comparator is connected to the voltage error signal. The comparator is used to output a control signal based on the triangular wave and the voltage error signal.

[0020] Optionally, the signal enhancement unit includes a signal driver;

[0021] The input terminal of the signal driver is connected to the signal generation unit, and the output terminal of the signal driver is connected to the control terminal of the first power switch. The signal driver is used to generate a drive signal according to the control signal generated by the signal generation unit, and the drive signal is used to drive the first power switch.

[0022] Optionally, the signal generation unit further includes: a voltage error signal generation module;

[0023] The first input terminal of the voltage error signal generation module is connected to the bus voltage, the second input terminal of the voltage error signal generation module is connected to the reference voltage, and the output terminal of the voltage error signal generation module is connected to a comparator. The voltage error signal generation module is used to generate a voltage error signal based on the bus voltage and the reference voltage.

[0024] Optionally, the shunt circuit of the solar cell array also includes a first resistor, a first capacitor, a second resistor, a second capacitor, and a third resistor;

[0025] The first end of the first resistor is connected to the second end of the first power switch, and the second end of the first resistor is connected to the positive terminal of the solar cell array and the first end of the second power switch.

[0026] The first capacitor is connected in series with the second resistor. The first capacitor is connected to the negative terminal of the solar cell array, and the second resistor is connected to the positive terminal of the solar cell array. The second capacitor is connected in series with the third resistor. The second capacitor is connected to the negative terminal of the solar cell array, and the second resistor is connected to the positive terminal of the solar cell array.

[0027] According to another aspect of the present invention, a spacecraft power supply system is provided, which includes a shunt circuit for a solar cell array according to any embodiment of the present invention.

[0028] The technical solution of this utility model embodiment is that the control drive module generates a drive signal according to the working state of the shunt circuit of the solar cell array. The drive signal drives the first power switch, and the inverter generates an inverted signal with opposite polarity according to the drive signal. The inverted signal drives the second power switch. In this way, the first power switch and the second power switch will not be turned on at the same time, thereby avoiding the voltage reverse flow phenomenon. Moreover, when the second power switch is turned on, the on-resistance is extremely small, thereby reducing the heat dissipation of the shunt circuit of the solar cell array and improving the energy conversion efficiency of the solar cell array.

[0029] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 A schematic diagram of the shunt circuit of a solar cell array provided in an embodiment of this utility model;

[0032] Figure 2 A schematic diagram of the shunt circuit of another solar cell array provided in an embodiment of this utility model;

[0033] Figure 3 This is a structural diagram of the signal generation unit provided in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the shunt circuit of another solar cell array provided in an embodiment of the present invention. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0036] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0037] Figure 1 This is a schematic diagram of the structure of a shunt circuit for a solar cell array provided in an embodiment of the present invention. The shunt circuit of the solar cell array is applied to a spacecraft power supply system. For example, the shunt circuit of the solar cell array regulates the output power of the power supply system to ensure that the bus voltage remains stable.

[0038] like Figure 1 As shown, the shunt circuit of the solar cell array includes: solar cell array 110, first power switch 120, second power switch 130, inverter 140 and control drive module 150;

[0039] The positive terminal of the solar cell array 110 is connected to the first terminal of the first power switch 120 and the first terminal of the second power switch 130, respectively. The negative terminal of the solar cell array 110 is connected to the second terminal of the first power switch 120. The second terminal of the second power switch 130 is connected to the first connection terminal A1 of the shunt circuit, and the negative terminal of the solar cell array 110 is connected to the second connection terminal A2 of the shunt circuit. The first connection terminal A1 and the second connection terminal A2 of the shunt circuit are used to connect to the bus or load. The control drive module 150 is connected to the control terminal of the first power switch 120. The control drive module 150 is used to generate a drive signal, and the first power switch 120 is used to turn on or off according to the drive signal. The control drive module 150 is also connected to the first terminal of the inverter 140. The second terminal of the inverter 140 is connected to the control terminal of the second power switch 130. The second power switch 130 is used to turn on or off according to the inverted signal output by the inverter 140. The inverted signal is inversely phase to the drive signal.

[0040] In this embodiment, the solar cell array 110 is a component capable of converting solar energy into electrical energy. The electrical energy generated by the solar cell array 110 can be supplied to the bus or distributed to various loads. The first power switch 120 and the second power switch 130 are switching components in the shunt circuit of the solar cell array 110. The on or off state of the first power switch 120 and the second power switch 130 can regulate the destination of the electrical energy generated by the solar cell array 110, thereby ensuring the stability of the bus voltage. For example, if the first power switch 120 is off and the second power switch 130 is on, the electrical energy generated by the solar cell array 110 is supplied to the bus; if the first power switch 120 is on and the second power switch 130 is off, the electrical energy generated by the solar cell array 110 is shunt to the ground. The control drive module 150 is a component that can generate drive signals according to the target operating state of the shunt circuit. For example, the target operating state of the shunt circuit can be a power supply state in which the solar cell array 110 supplies voltage to the bus or a shunt state in which the solar cell array 110 is shunt to the ground. The drive signal generated by the control drive module 150 can drive the first power switch 120 and the second power switch 130. The inverter 140 is a device that can reverse the polarity of the input signal before outputting it. For example, the drive signal output by the control drive module 150 is sent to the inverter 140, which inverts the drive signal to generate an inverted signal, which drives the second power switch 130.

[0041] The first connection terminal A1 of the shunt circuit can be the end of the positive terminal of the solar cell array 110 that supplies power to the bus, and the second connection terminal A2 of the shunt circuit can be the end of the negative terminal of the solar cell array 110 that supplies power to the load. The first connection terminal A1 and the second connection terminal A2 of the shunt circuit are used to connect to the bus or the load. When the bus voltage is too high, the solar cell array 110 needs to shunt the power to the ground. When the bus voltage does not exceed the preset range, the solar cell array 110 supplies voltage to the bus. The control drive module 150 is connected to the control terminal of the first power switch 120 and the first terminal of the inverter 140. The second terminal of the inverter 140 is connected to the control terminal of the second power switch 130. The control drive module 150 can generate a drive signal according to the working state of the shunt circuit. The inverter 140 can generate an inverted signal with opposite polarity according to the drive signal input by the control drive module 150. The drive signal drives the first power switch 120 to turn on or off, and the inverted signal drives the second power switch 130 to turn on or off. The first power switch 120 and the second power switch 130 are turned on when the corresponding control terminals are level signals of the same polarity. For example, both the first power switch 120 and the second power switch 130 are turned on when the signal is low and turned off when the signal is high; or both the first power switch 120 and the second power switch 130 are turned on when the signal is high and turned off when the signal is low.

[0042] The following example illustrates how both the first power switch 120 and the second power switch 130 are turned on under a high-level drive signal and turned off under a low-level drive signal. For instance, when the bus voltage is too high, the control drive module 150 generates a high-level drive signal. This high-level drive signal turns on the first power switch 120, and the inverter 140 generates a low-level inverted signal based on the high-level drive signal. This low-level inverted signal turns off the second power switch 130. When the second power switch 130 is turned off, it can be considered as an isolation diode, preventing reverse current from flowing. At this time, the solar cell array 110 shunts the current to ground and no longer supplies power to the bus. When the bus voltage does not exceed the preset range, the control drive module 150 generates a low-level drive signal. The low-level drive signal can turn off the first power switch 120. The inverter 140 generates a high-level inverted signal according to the low-level drive signal. The high-level inverted signal turns on the second power switch 130. When the second power switch 130 is turned on, the on-resistance is extremely small. The second power switch 130 can be regarded as an ideal diode. At this time, the solar cell array 110 supplies power to the bus.

[0043] According to the technical solution of this utility model embodiment, the control drive module generates a drive signal based on the working state of the shunt circuit of the solar cell array. The drive signal drives the first power switch, and the inverter generates an inverted signal with opposite polarity based on the drive signal. The inverted signal drives the second power switch, so that the first power switch and the second power switch will not be turned on at the same time, thereby avoiding voltage reverse flow. Furthermore, the on-resistance of the second power switch is extremely small when it is turned on, thereby reducing the heat dissipation of the shunt circuit of the solar cell array and improving the energy conversion efficiency of the solar cell array.

[0044] Optionally, the first power switch 120 includes a first transistor, and the second power switch 130 includes a second transistor, wherein the first transistor and the second transistor have the same channel type.

[0045] In this design, the first transistor and the second transistor have the same channel type; both are N-channel MOSFETs. By using transistors with the same channel type, it can be ensured that when the control terminals of the first power switch 120 and the second power switch 130 are connected to drive signals of opposite polarity, the switching states of the first power switch 120 and the second power switch 130 are opposite. For example, the first power switch 120 is on and the second power switch 130 is off, or the first power switch 120 is off and the second power switch 130 is on.

[0046] Specifically, the shunt circuit of the solar cell array includes: a solar cell array 110, a first power switch 120, a second power switch 130, an inverter 140, and a control drive module 150. The first terminal of the first power switch 120 is the drain of a first transistor, the second terminal of the first power switch 120 is the source of the first transistor, and the control terminal of the first power switch 120 is the gate of the first transistor. The first terminal of the second power switch 130 is the source of a second transistor, the second terminal of the second power switch 130 is the drain of the second transistor, and the control terminal of the second power switch 130 is the gate of the second transistor. The positive terminal of the solar cell array 110 is connected to the drain of the first power switch 120 and the source of the second power switch 130, respectively, and the negative terminal of the solar cell array 110 is connected to the source of the first power switch 120.

[0047] Figure 2 A schematic diagram of the shunt circuit for another solar cell array provided in this embodiment of the present invention is shown below. Figure 2 As shown, optionally, the shunt circuit of the solar cell array also includes a control chip 210. One end of the control chip 210 is connected to the second end of the inverter 140, and the other end of the control chip 210 is connected to the control terminal of the second power switch 130, for driving the second power switch 130 according to the inverted signal.

[0048] Among them, the control chip 210 is a driver chip that can enhance the driving capability of the inverted signal. For example, the control chip 210 can be an LTC4359HS8. By connecting the inverter and the second power switch 130 through the control chip 210, the driving capability of the signal is enhanced, so that the second power switch can be turned on or off quickly and stably.

[0049] Specifically, one end of the control chip 210 is connected to the output of the inverter 140 to receive the inverted signal output by the inverter 140, and the other end of the control chip 210 is connected to the control terminal of the second power switch 130 to enhance the driving capability of the inverted signal and control the second power switch 130 to quickly and stably turn on or off. By driving the second power switch 130 through the control chip 210, the second power switch 130 can be turned on or off quickly and stably, reducing switching losses and improving the efficiency of the shunt circuit of the solar cell array.

[0050] Optionally, inverter 140 includes a NOT gate.

[0051] Among them, the NOT gate can convert the input high-level drive signal into a low-level inverted signal output, or the NOT gate can convert the input low-level drive signal into a high-level inverted signal output.

[0052] Specifically, one end of inverter 140 is connected to signal enhancement unit 230, and the other end of inverter 140 is connected to control chip 210. The other end of control chip 210 is connected to second power switch 130. The drive signal generated by signal enhancement unit 230 is connected to first power switch 120. After being logically inverted by inverter 140, an inverted signal with the opposite polarity to the drive signal is generated. Control chip 210 controls second power switch 130 according to the inverted signal. By setting the NOT gate, the drive signal used to drive first power switch 120 and the inverted signal used to drive second power switch 130 can always be in an inverted state, avoiding voltage backflow in the shunt circuit of solar cell array caused by inconsistent control timing of first power switch 120 and second power switch 130.

[0053] See also Figure 2 Optionally, the control drive module 150 includes: a signal generation unit 220 and a signal enhancement unit 230;

[0054] The input terminal of the signal generation unit 220 is connected to the voltage error signal, and the output terminal of the signal generation unit 220 is connected to the input terminal of the signal enhancement unit 230. The signal generation unit 220 is used to generate a control signal based on the voltage error signal. The voltage error signal is the error signal of the bus voltage between the first connection terminal A1 and the second connection terminal A2 of the shunt circuit. The output terminal of the signal enhancement unit 230 serves as the output terminal of the control drive module 150. The signal enhancement unit 230 is used to generate and output a drive signal based on the control signal. The drive capability of the drive signal is greater than that of the control signal.

[0055] Among them, the signal generation unit 220 is a circuit that can generate control signals according to the working state of the shunt circuit of the solar cell array, and the signal enhancement unit 230 is a circuit that can amplify the power of the control signals, enhance the driving capability of the control signals, and thus generate driving signals.

[0056] Optionally, the signal enhancement unit 230 includes a signal driver;

[0057] The input terminal of the signal driver is connected to the signal generation unit 220, and the output terminal of the signal driver is connected to the control terminal of the first power switch 120. The signal driver is used to generate a drive signal according to the control signal generated by the signal generation unit 220, and the drive signal is used to drive the first power switch 120.

[0058] Among them, the signal driver refers to a device that can enhance the driving capability of the control signal. For example, the signal driver is a push-pull circuit composed of two transistors with opposite polarities. The input terminal of the push-pull circuit is connected to the control signal generated by the signal generation unit 220. The push-pull circuit can amplify the control signal to generate a driving signal.

[0059] Specifically, the input terminal of the signal generation unit 220 is connected to a voltage error signal. If the voltage error signal exceeds a first preset threshold, it indicates that the bus voltage is excessive, and the signal generation unit 220 generates a high-level control signal. If the voltage error signal is lower than a second preset threshold, where the second preset threshold can be less than or equal to the first preset threshold, it indicates that power needs to be supplied to the bus, and the signal generation unit 220 generates a low-level control signal. The output terminal of the signal generation unit 220 is connected to the input terminal of the signal enhancement unit 230. The signal enhancement unit 230 enhances the driving capability of the control signal generated by the signal generation unit 220, generating a driving signal. The output terminal of the signal enhancement unit 230 serves as the output terminal of the control drive module, and the signal enhancement unit 230 outputs the driving signal. Through the signal generation unit 220 and the signal enhancement unit 230, control signals and driving signals can be generated according to the operating state of the shunt circuit of the solar cell array, thereby controlling the conduction or cutoff of the first power switch 120 and the second power switch 130, and thus achieving bus voltage stability. It should be noted that in the embodiments of the present invention, the first preset threshold and the second preset threshold are for clarification and are not intended as specific limiting conditions of the embodiments of the present invention. The values ​​of the first preset threshold and the second preset threshold can be set according to actual needs.

[0060] Figure 3 This is a structural diagram of the signal generation unit provided in an embodiment of the present invention. The comparator can generate a high-level control signal or a low-level control signal by comparing the signal of the triangular wave generator with the voltage error signal.

[0061] like Figure 3 As shown, optionally, the signal generation unit includes a triangular wave generator 221 and a comparator 222;

[0062] The triangular wave generator 221 is a pulse width modulation (PWM) controller. The PWM controller is used to output a reference waveform, which is a triangular wave. The comparator 222 has a first input port and a second input port. The PWM controller is connected to the first input port of the comparator 222, and the second input port of the comparator 222 is connected to the voltage error signal. The comparator 222 is used to output control signals for the triangular wave and the voltage error signal.

[0063] The triangular wave generator 221 is a PWM controller, which can generate a reference waveform with a fixed amplitude and period. For example, the reference waveform generated by the PWM controller is a triangular wave with an amplitude of 1. The comparator 222 is a device that can compare the amplitudes of two input signals in real time and output a logic level signal based on the comparison result. For example, the first input terminal of the comparator 222 is connected to the triangular wave signal generated by the triangular wave generator 221, and the second input terminal is connected to the voltage error signal. The comparator 222 compares the amplitudes of the triangular wave signal and the voltage error signal in real time. If the voltage error signal is too large, after comparison with the triangular wave, the comparator 222 outputs a high-level control signal; if the voltage error signal is too small, after comparison with the triangular wave, the comparator 222 outputs a low-level control signal.

[0064] See also Figure 3 Optionally, the signal generation unit 220 further includes a voltage error signal generation module 223;

[0065] The first input terminal of the voltage error signal generation module 223 is connected to the bus voltage, the second input terminal of the voltage error signal generation module 223 is connected to the reference voltage, and the output terminal of the voltage error signal generation module 223 is connected to the comparator 222. The voltage error signal generation module 223 is used to generate a voltage error signal based on the bus voltage and the reference voltage.

[0066] Among them, the voltage error signal generation module 223 is a component that can generate a voltage error signal according to the working state of the solar cell array. For example, the voltage error signal generation module 223 can be a main error amplifier (MEA). The voltage error signal generation module 223 is connected to the bus voltage and the reference voltage, and generates a voltage error signal according to the magnitude of the bus voltage and the reference voltage.

[0067] Specifically, the reference voltage can be set to a preset value according to specific circumstances. If the reference voltage exceeds the bus voltage, the voltage error signal generation module 223 outputs a signal with an amplitude of x. Comparator 222 compares a voltage error signal with an amplitude of x with a triangular wave signal with an amplitude of 1. Comparator 222 outputs a high- or low-level control signal with an adjustable duty cycle. When the amplitude of x is 1, comparator 222 outputs a low-level control signal with a duty cycle of 0%. If the bus voltage exceeds the reference voltage, the voltage error signal generation module 223 outputs a signal with an amplitude of 0. Comparator 222 compares the signal with an amplitude of 0 with a triangular wave signal with an amplitude of 1. Comparator 222 outputs a high-level control signal with a duty cycle of 100%.

[0068] For example, when the bus voltage is less than the reference voltage and the difference between the reference voltage and the bus voltage exceeds the third preset threshold, the voltage error signal generation module 223 outputs an amplitude of 1, the comparator 222 outputs a low-level control signal with a duty cycle of 0%, the signal enhancement unit generates a drive signal based on the low-level control signal with a duty cycle of 0%, the drive signal controls the first power switch to turn off, the inverter generates a high-level inverted signal based on the low-level drive signal, the control chip controls the second power switch to turn on based on the high-level inverted signal, and the solar cell array supplies power to the bus. At this time, the shunt circuit of the solar cell array is in full power supply mode. When the bus voltage exceeds the reference voltage, the voltage error signal generation module 223 outputs an amplitude of 0, the comparator 222 outputs a high-level control signal with a 100% duty cycle, the signal enhancement unit generates a drive signal based on the high-level control signal with a 100% duty cycle, the drive signal controls the first power switch to turn on, the inverter generates a low-level inverted signal based on the high-level drive signal, the control chip controls the second power switch to turn off quickly based on the high-level inverted signal, and the solar cell array is grounded and shunted. At this time, the shunt circuit of the solar cell array is working in full shunt state. When the bus voltage is less than the reference voltage, and the difference between the reference voltage and the bus voltage is less than the fourth preset threshold, the voltage error signal generation module 223 outputs an amplitude of x, the comparator 222 outputs a high / low level control signal with a certain duty cycle, the signal enhancement unit generates a drive signal based on the high / low level control signal with a certain duty cycle, the drive signal controls the first power switch to turn off or on, the inverter generates an inverted signal complementary to the high / low level with a certain duty cycle based on the low-level drive signal, and the control chip controls the second power switch to turn on or off based on the inverted signal complementary to the high / low level with a certain duty cycle. At this time, the shunt circuit of the solar cell array operates in the shunt state. It should be noted that in this embodiment of the invention, the fourth preset threshold can be less than or equal to the third preset threshold. The third and fourth preset thresholds are for clarity and are not intended as specific limitations of this embodiment of the invention. The values ​​of the third and fourth preset thresholds can be set according to actual needs.

[0069] Figure 4 A schematic diagram of the shunt circuit of another solar cell array provided in this embodiment of the present invention is shown below. Figure 4 As shown, the shunt circuit of the solar cell array includes: solar cell array 110, first power switch, second power switch, inverter and control drive module 150;

[0070] The positive terminal of the solar cell array 110 is connected to the first terminal of the first power switch and the first terminal of the second power switch, respectively, and the negative terminal of the solar cell array 110 is connected to the second terminal of the first power switch. The second terminal of the second power switch is connected to the first connection terminal A1 of the shunt circuit, and the negative terminal of the solar cell array is connected to the second connection terminal A2 of the shunt circuit. The first connection terminal A1 and the second connection terminal A2 of the shunt circuit are used to connect to the bus or load. The control drive module is connected to the control terminal of the first power switch and is used to generate a drive signal. The first power switch is used to turn on or off according to the drive signal. The control drive module is also connected to the first terminal of the inverter. The second terminal of the inverter is connected to the control terminal of the second power switch. The second power switch is used to turn on or off according to the inverted signal output by the inverter. The inverted signal is inversely phase to the drive signal.

[0071] Optionally, the first power switch includes a first transistor MOSFET1, and the second power switch includes a second transistor MOSFET2, wherein the first transistor MOSFET1 and the second transistor MOSFET2 have the same channel type.

[0072] Optionally, the shunt circuit of the solar cell array also includes a control chip 210. One end of the control chip 210 is connected to the second end of the inverter, and the other end of the control chip 210 is connected to the control terminal of the second power switch, for driving the second power switch according to the inverted signal.

[0073] Optionally, the inverter includes a NOT gate D.

[0074] Optionally, the control drive module includes: a signal generation unit and a signal enhancement unit;

[0075] The input terminal of the signal generation unit is connected to the voltage error signal, and the output terminal of the signal generation unit is connected to the input terminal of the signal enhancement unit. The signal generation unit is used to generate a control signal based on the voltage error signal. The voltage error signal is the error signal of the bus voltage between the first connection terminal A1 and the second connection terminal A2 of the shunt circuit. The output terminal of the signal enhancement unit serves as the output terminal of the control drive module. The signal enhancement unit is used to generate and output a drive signal based on the control signal. The drive capability of the drive signal is greater than that of the control signal.

[0076] Optionally, the signal generation unit includes a triangular wave generator 221 and a comparator 222;

[0077] The triangular wave generator 221 is a PWM controller, which is used to output a reference waveform, which is a triangular wave. The comparator 222 has a first input port and a second input port. The PWM controller is connected to the first input port of the comparator 222, and the second input port of the comparator 222 is connected to the voltage error signal. The comparator 222 is used to output control signals for the triangular wave and the voltage error signal.

[0078] Optionally, the signal generation unit further includes: a voltage error signal generation module 223;

[0079] The first input terminal of the voltage error signal generation module 223 is connected to the bus voltage, the second input terminal of the voltage error signal generation module 223 is connected to the reference voltage, and the output terminal of the voltage error signal generation module 223 is connected to the comparator 222. The voltage error signal generation module 223 is used to generate a voltage error signal based on the bus voltage and the reference voltage.

[0080] Optionally, the signal enhancement unit includes a signal driver 310;

[0081] The input terminal of the signal driver 310 is connected to the signal generation unit, and the output terminal of the signal driver 310 is connected to the control terminal of the first power switch. The signal driver 310 is used to generate a drive signal according to the control signal generated by the signal generation unit, and the drive signal is used to drive the first power switch.

[0082] Optionally, the shunt circuit of the solar cell array also includes a first resistor R1, a first capacitor C1, a second resistor R2, a second capacitor C2, and a third resistor R3;

[0083] The first end of the first resistor R1 is connected to the second end of the first power switch, and the second end of the first resistor R2 is connected to the positive terminal of the solar cell array 110 and the first end of the second power switch.

[0084] The first capacitor C1 is connected in series with the second resistor R2. The first capacitor C2 is connected to the negative terminal of the solar cell array 110, and the second resistor R2 is connected to the positive terminal of the solar cell array 110. The second capacitor C2 is connected in series with the third resistor R3. The second capacitor C2 is connected to the negative terminal of the solar cell array 110, and the second resistor R2 is connected to the positive terminal of the solar cell array 110.

[0085] The first resistor R1 is connected between the positive terminal of the solar cell array 110 and the first isolating switch to prevent instantaneous overcurrent from damaging the first isolating switch or other devices. The first resistor R1 improves the safety and stability of the solar cell array shunt circuit.

[0086] The first capacitor C1 is connected in series with the second resistor R2, and the second capacitor C2 is connected in series with the third resistor R3. This is used to absorb transient spikes. For example, when the second power switch is turned off, an extremely high reverse induced voltage will be generated, which will be superimposed on the bus to form a "voltage spike". The series RC network can absorb the transient spike, ensuring the voltage stability of the solar bus, avoiding damage to the equipment by transient spikes, and improving the stability of the shunt circuit of the solar cell array.

[0087] This utility model provides a spacecraft power supply system, which includes a shunt circuit for a solar cell array according to any embodiment of this utility model, and has the beneficial effects of the shunt circuit for a solar cell array according to any embodiment of this utility model.

[0088] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0089] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A shunt circuit for a solar cell array, characterized in that, include: Solar cell array, first power switch, second power switch, inverter and control drive module; The positive terminal of the solar cell array is connected to the first terminal of the first power switch and the first terminal of the second power switch, respectively, and the negative terminal of the solar cell array is connected to the second terminal of the first power switch. The second terminal of the second power switch is connected to the first terminal of the shunt circuit, and the negative terminal of the solar cell array is connected to the second terminal of the shunt circuit. The first terminal and the second terminal of the shunt circuit are used to connect to the bus or load. The control drive module is connected to the control terminal of the first power switch. The control drive module is used to generate a drive signal, and the first power switch is used to turn on or off according to the drive signal. The control drive module is also connected to the first terminal of the inverter, and the second terminal of the inverter is connected to the control terminal of the second power switch. The second power switch is used to turn on or off according to the inverted signal output by the inverter, and the inverted signal is inverse of the drive signal.

2. The shunt circuit for the solar cell array according to claim 1, characterized in that, The first power switch includes a first transistor, and the second power switch includes a second transistor, wherein the first transistor and the second transistor have the same channel type.

3. The shunt circuit for the solar cell array according to claim 1, characterized in that, The shunt circuit of the solar cell array also includes a control chip. One end of the control chip is connected to the second end of the inverter, and the other end of the control chip is connected to the control terminal of the second power switch, for driving the second power switch according to the inverted signal.

4. The shunt circuit for the solar cell array according to claim 1, characterized in that, The inverter includes a NOT gate.

5. The shunt circuit for the solar cell array according to claim 1, characterized in that, The control drive module includes: a signal generation unit and a signal enhancement unit; The input terminal of the signal generation unit is connected to a voltage error signal, and the output terminal of the signal generation unit is connected to the input terminal of the signal enhancement unit. The signal generation unit is used to generate a control signal based on the voltage error signal. The voltage error signal is the error signal of the bus voltage between the first connection terminal and the second connection terminal of the shunt circuit. The output terminal of the signal enhancement unit serves as the output terminal of the control drive module. The signal enhancement unit is used to generate and output the drive signal according to the control signal. The drive capability of the drive signal is greater than that of the control signal.

6. The shunt circuit for the solar cell array according to claim 5, characterized in that, The signal generation unit includes a triangular wave generator and a comparator; The triangular wave generator is a PWM controller, which is used to output a reference waveform, which is a triangular wave. The comparator has a first input port and a second input port. The PWM controller is connected to the first input port of the comparator, and the second input port of the comparator is connected to a voltage error signal. The comparator is used to output the control signal based on the triangular wave and the voltage error signal.

7. The shunt circuit for the solar cell array according to claim 5, characterized in that, The signal enhancement unit includes a signal driver; The input terminal of the signal driver is connected to the signal generation unit, and the output terminal of the signal driver is connected to the control terminal of the first power switch. The signal driver is used to generate the drive signal according to the control signal generated by the signal generation unit, and the drive signal is used to drive the first power switch.

8. The shunt circuit for the solar cell array according to claim 6, characterized in that, The signal generation unit further includes: a voltage error signal generation module; The first input terminal of the voltage error signal generation module is connected to the bus voltage, the second input terminal of the voltage error signal generation module is connected to the reference voltage, and the output terminal of the voltage error signal generation module is connected to the comparator. The voltage error signal generation module is used to generate a voltage error signal based on the bus voltage and the reference voltage.

9. The shunt circuit for the solar cell array according to claim 4, characterized in that, It also includes a first resistor, a first capacitor, a second resistor, a second capacitor, and a third resistor; The first end of the first resistor is connected to the second end of the first power switch, and the second end of the first resistor is connected to the positive terminal of the solar cell array and the first end of the second power switch. The first capacitor is connected in series with the second resistor, the first capacitor is connected to the negative terminal of the solar cell array, and the second resistor is connected to the positive terminal of the solar cell array; the second capacitor is connected in series with the third resistor, the second capacitor is connected to the negative terminal of the solar cell array, and the second resistor is connected to the positive terminal of the solar cell array.

10. A spacecraft power supply system, characterized in that, Includes the shunt circuit of the solar cell array according to any one of claims 1-9.

Images