A circuit to solve the trickle charging of S3R power system under constant light conditions

Abstract

A circuit method for solving the trickle charging of the S3R power system under normal illumination conditions. During the normal illumination period of the satellite, the enable switch is turned on, and the BEA signal is obtained by collecting the battery voltage, thereby controlling whether the domain signal is valid. The hysteresis comparison circuit is essentially a hysteresis comparator. During the charging process, when the battery voltage is lower than the set value VB th‑ When the BEA signal is low, the transistors Q1 and Q2 are turned off. At this time, the domain signal is valid, which effectively adjusts the PWM output to realize the charging function. The battery voltage continues to rise until the battery voltage is higher than the set value VB th+ When the BEA signal is high, Q1 and Q2 are saturated and turned on, the PWM signal continues to output a high level, the S3R regulation circuit forces the power output of the power stabilization module circuit to be turned off, the solar cell array is shunted, the battery enters the discharge state to maintain the rear-end load, and the battery voltage continues to decrease to the set value VB th‑ When the battery is fully charged, it enters the next cycle, effectively avoiding the trickle charging of the S3R power system under normal light conditions.

Description

Technical Field

[0001] The invention relates to the technical field of aerospace power supply, and in particular to a circuit for solving trickle charging of an S3R power supply system under normal illumination conditions. Background Art

[0002] The lithium-ion battery pack is one of the important components of the power subsystem. As the energy heart of the entire satellite, it receives solar cell charging during the illumination period and provides energy storage power to the onboard equipment during the shadow period. The traditional S3R power system charges the battery in constant current and constant voltage. Generally, when the battery power reaches about 80%, it enters constant voltage charging, which is the trickle charging mode. At this time, the charging speed will gradually slow down until the battery is fully charged, but the trickle charging process is uncontrollable. When the satellite enters the constant illumination orbit, the energy is sufficient at this time, and the photovoltaic effect of the solar cell array converts solar energy into electrical energy to charge the battery. When the battery enters the saturated state, due to the influence of the internal resistance voltage drop of the cable and the battery pack, the trickle charging will always exist. Since the satellite is in a constant illumination orbit, the trickle charging time of the battery is too long, which may cause the hidden danger of battery explosion. Therefore, it is necessary to solve the trickle charging of the S3R power system under the condition of constant illumination, which is of great significance to the on-orbit safety of the battery. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a circuit for solving the problem of trickle charging of the S3R power supply system under normal illumination. The circuit structure is composed of a transistor, a resistor, a comparator, a relay, etc. The electrical assembly process is simple, the device selection is all conventional components, and it is easy to implement in engineering.

[0004] The technical solution adopted by the present invention is:

[0005] A circuit for solving trickle charging of an S3R power system under normal illumination conditions, comprising: a reference circuit, a battery voltage divider circuit, a hysteresis comparison circuit, an MEA circuit, an operational amplifier circuit, an S3R regulation circuit, a power stabilization module circuit, an enabling switch control circuit, and a domain signal locking circuit; wherein:

[0006] A reference circuit outputs a reference voltage to a hysteresis comparison circuit;

[0007] A battery voltage divider circuit outputs a battery voltage signal to a hysteresis comparison circuit;

[0008] The hysteresis comparator circuit compares the battery voltage signal with the reference signal. When the battery voltage signal is lower than the set battery voltage lower limit VB th-When the BEA signal formed by the hysteresis comparison circuit outputs a low level, the transistors Q1 and Q2 in the domain signal locking circuit are turned off, the domain signal is unlocked to the initial setting value, and the S3R regulation circuit charges the battery pack; when the battery voltage signal is higher than the set battery voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparison circuit outputs a high level, the transistors Q1 and Q2 in the domain signal locking circuit are turned on, the domain signal is locked to a low level, and the S3R regulation circuit stops charging the battery pack by regulating the power stabilization module circuit;

[0009] The enabling switch control circuit controls the on and off state through external instructions to realize whether the BEA signal is connected to the domain signal locking circuit;

[0010] The sub-domain signal locking circuit, when the enabling switch control circuit is turned on, when the BEA signal is at a high level, the sub-domain signal is locked to a low level; when the BEA signal is at a low level, the sub-domain signal is locked to an initial setting value; the sub-domain signal is sent to the operational amplifier circuit;

[0011] The power stabilization module circuit is connected to the battery pack to realize the charging function of the battery pack;

[0012] The MEA circuit performs error amplification on the output power VBUS of the power stabilization module circuit, and sends the output MEA signal to the operational amplifier circuit;

[0013] An operational amplifier circuit performs differential amplification on the MEA signal and the sub-domain signal, and the output end is connected to the S3R regulation circuit;

[0014] The S3R regulation circuit outputs a PWM control signal to control the output power of the power stabilization module circuit and complete the battery pack charging function.

[0015] Furthermore, the reference circuit Vref is a fixed voltage value, and uses a voltage regulator to generate a standard voltage signal.

[0016] Further, the battery voltage dividing circuit includes resistors R1 and R2;

[0017] One end of the resistor R1 is connected to the battery pack voltage sampling signal VBAT, and the other end is connected in series with the resistor R2. The other end of R2 is connected to the battery sampling ground line. The connection point between R1 and R2 is connected to the hysteresis comparison circuit as the battery voltage sampling signal.

[0018] Further, the hysteresis comparison circuit includes a comparator working power supply VCC, resistors R3, R4, R5, and a comparator;

[0019] The two ends of the resistor R3 are respectively connected across the in-phase terminal and the output terminal of the comparator;

[0020] One end of the resistor R4 is connected to the comparator working power supply VCC, and the other end is connected to the comparator power input port;

[0021] One end of the resistor R5 is connected to the comparator working power supply VCC, and the other end is connected to the signal output port of the comparator;

[0022] The output signal of the reference circuit Vref is connected to the inverting terminal of the comparator;

[0023] The output of the comparator is the BEA signal.

[0024] Furthermore, the enabling switch control circuit includes a magnetic latching relay K1.

[0025] Further, the domain signal locking circuit includes a domain circuit, NPN transistors Q1 and Q2;

[0026] The domain division circuit generates a constant reference voltage, namely the domain division signal, which is fed into the negative input terminal of the operational amplifier circuit; the collector of transistor Q1 is connected to the domain division circuit, the emitter of transistor Q1 is connected to the collector of transistor Q2, the bases of transistors Q1 and Q2 are connected, and are also connected to the output terminal of the magnetic latching relay K1, and the collector of transistor Q2 is connected to the signal ground wire.

[0027] Furthermore, when the satellite enters the constant illumination orbit, the enable switch K1 is turned on, and the hysteresis comparison circuit compares the battery voltage sampling signal with the reference signal Vref to generate a BEA signal to control the state of transistors Q1 and Q2; during the charging process, when the battery voltage is lower than the set value VB th- When the BEA signal formed by the hysteresis comparator is low level, the transistors Q1 and Q2 are cut off, and the domain signal is valid at this time. The S3R regulation circuit controls the power stabilization module circuit to output full power, realizing the battery pack charging function.

[0028] The battery voltage continues to rise to the set charging voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparator is high, the transistors Q1 and Q2 are saturated and turned on. At this time, the domain signal fails and is locked at a low level. The PWM signal output by the S3R regulation circuit continues to be high, and the power stabilization module circuit is controlled to turn off the power output, that is, turn off the charging function of the battery pack, effectively avoiding trickle charging of the S3R power system under normal light conditions.

[0029] Furthermore, the resistors R1, R2 and R3 are adjusted to adjust the hysteresis interval [VB th -,VB th+ ] so that its upper and lower limits are lower than the bus charging final voltage VBUS under normal conditions.

[0030] Furthermore, whether the BEA signal effectively participates in the S3R regulation circuit can be directly controlled by the enable switch K1. When the satellite works in a normal illumination orbit, K1 is enabled; when the satellite works in an illumination-Earth shadow orbit, K1 is disabled.

[0031] Furthermore, when the enable switch K1 is enabled, the BEA signal controls the states of the transistors Q1 and Q2; when the BEA signal outputs a high level, the transistors Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit fails and is locked to a low level, and the PWM signal output by the S3R regulation circuit continues to be a high level, forcing the output of the power stabilization module circuit to be turned off; when the BEA signal outputs a low level, the transistors Q1 and Q2 are turned off, the fixed voltage signal in the domain circuit is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power, thereby realizing the battery pack charging function;

[0032] Transistors Q1 and Q2 are used in series. After Q2 is saturated and turned on, Q1 is also saturated and turned on, which can effectively avoid the failure of a single transistor and improve the reliability of the circuit.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] In the process of battery charging, when the battery voltage is lower than 28V, Q1 and Q2 are turned off, the fixed voltage signal in the domain circuit is valid, and the S3R regulating circuit controls the power stabilization module circuit to output full power to realize the charging of the battery pack; when the battery voltage is higher than 28V, Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit is locked to a low level, and the S3R regulating circuit controls the power stabilization module circuit to turn off the power output, that is, the charging function of the battery pack is turned off, and the battery enters the discharge state. When the battery is discharged to the battery voltage lower than 27V, Q1 and Q2 are turned off, and the next cycle is entered again. It is ensured that the battery always has a charging and discharging process during the normal light period, and the trickle charging of the S3R power supply system under normal light conditions is effectively avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] An embodiment of a circuit for solving trickle charging of an S3R power supply system under normal illumination conditions and accompanying drawings are provided in the present invention.

[0036] Figure 1 It is a structural block diagram of a circuit for solving the trickle charging problem of an S3R power supply system under normal illumination conditions according to an embodiment of the present invention.

[0037] Figure 2 A schematic diagram of an implementation form of the hysteresis comparison circuit in the present invention;

[0038] Figure 3 A schematic diagram of an implementation form of the enabling switch control circuit in the present invention; DETAILED DESCRIPTION

[0039] A circuit for solving trickle charging of an S3R power system under normal light conditions will be further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] like Figure 1 As shown, the present invention proposes a circuit for solving the trickle charging of the S3R power system under normal illumination conditions, including: a reference circuit, a battery voltage divider circuit, a hysteresis comparison circuit, an MEA circuit, an operational amplifier circuit, an S3R regulation circuit, a power stabilization module circuit, an enabling switch control circuit and a domain signal locking circuit; wherein:

[0041] A reference circuit outputs a reference voltage to a hysteresis comparison circuit;

[0042] A battery voltage divider circuit outputs a battery voltage signal to a hysteresis comparison circuit;

[0043] The hysteresis comparator circuit compares the battery voltage signal with the reference signal. When the battery voltage signal is lower than the set battery voltage lower limit VB th -, the BEA signal formed by the hysteresis comparison circuit outputs a low level, the transistors Q1 and Q2 in the domain signal locking circuit are turned off, the domain signal is unlocked to the initial setting value, and the S3R regulation circuit charges the battery pack; when the battery voltage signal is higher than the set battery voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparison circuit outputs a high level, the transistors Q1 and Q2 in the domain signal locking circuit are turned on, the domain signal is locked to a low level, and the S3R regulation circuit stops charging the battery pack by regulating the power stabilization module circuit;

[0044] The enabling switch control circuit controls the on and off state through external instructions to realize whether the BEA signal is connected to the domain signal locking circuit;

[0045] The sub-domain signal locking circuit, when the enabling switch control circuit is turned on, when the BEA signal is at a high level, the sub-domain signal is locked to a low level; when the BEA signal is at a low level, the sub-domain signal is locked to an initial setting value; the sub-domain signal is sent to the operational amplifier circuit;

[0046] The power stabilization module circuit is connected to the battery pack to realize the charging function of the battery pack;

[0047] The MEA circuit performs error amplification on the output power VBUS of the power stabilization module circuit, and sends the output MEA signal to the operational amplifier circuit;

[0048] An operational amplifier circuit performs differential amplification on the MEA signal and the sub-domain signal, and the output end is connected to the S3R regulation circuit;

[0049] The S3R regulation circuit outputs a PWM control signal to control the output power of the power stabilization module circuit and complete the battery pack charging function.

[0050] like Figure 1 As shown, the reference circuit Vref described in the present invention is a fixed voltage value, and uses a voltage regulator to generate a standard voltage signal.

[0051] like Figure 1 As shown, the battery voltage divider circuit described in the present invention includes resistors R1 and R2;

[0052] One end of the resistor R1 is connected to the battery pack voltage sampling signal VBAT, and the other end is connected in series with the resistor R2. The other end of R2 is connected to the battery sampling ground line. The connection point between R1 and R2 is connected to the hysteresis comparison circuit as the battery voltage sampling signal.

[0053] like Figure 1 As shown, the hysteresis comparison circuit described in the present invention includes a comparator working power supply VCC, resistors R3, R4, R5, and a comparator;

[0054] The two ends of the resistor R3 are respectively connected across the in-phase terminal and the output terminal of the comparator;

[0055] One end of the resistor R4 is connected to the comparator working power supply VCC, and the other end is connected to the comparator power input port;

[0056] One end of the resistor R5 is connected to the comparator working power supply VCC, and the other end is connected to the signal output port of the comparator;

[0057] The output signal of the reference circuit Vref is connected to the inverting terminal of the comparator;

[0058] The output of the comparator is the BEA signal.

[0059] like Figure 1 As shown, the enabling switch control circuit in the present invention is implemented by a magnetic latching relay K1.

[0060] like Figure 1 As shown, the domain signal locking circuit in the present invention includes a domain circuit, NPN transistors Q1 and Q2;

[0061] The domain division circuit generates a constant reference voltage, namely the domain division signal, which is fed into the negative input terminal of the operational amplifier circuit; the collector of transistor Q1 is connected to the domain division circuit, the emitter of transistor Q1 is connected to the collector of transistor Q2, the bases of transistors Q1 and Q2 are connected, and are also connected to the output terminal of the magnetic latching relay K1, and the collector of transistor Q2 is connected to the signal ground wire.

[0062] Working principle of the present invention:

[0063] When the satellite enters the constant illumination orbit, the enable switch K1 is turned on, and the hysteresis comparison circuit compares the battery voltage sampling signal with the reference signal Vref to generate a BEA signal to control the state of transistors Q1 and Q2; during the charging process, when the battery voltage is lower than the set value VB th -, the BEA signal formed by the hysteresis comparator is at a low level, and the transistors Q1 and Q2 are cut off. At this time, the domain signal is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power, realizing the battery pack charging function;

[0064] The battery voltage continues to rise to the set charging voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparator is high, the transistors Q1 and Q2 are saturated and turned on. At this time, the domain signal fails and is locked at a low level. The PWM signal output by the S3R regulation circuit continues to be high, and the power stabilization module circuit is controlled to turn off the power output, that is, turn off the charging function of the battery pack, effectively avoiding trickle charging of the S3R power system under normal light conditions.

[0065] By adjusting the resistors R1, R2 and R3, the hysteresis range of the battery voltage [VB th -,VB th+ ] so that its upper and lower limits are lower than the bus charging final voltage VBUS under normal conditions.

[0066] Whether the BEA signal effectively participates in the S3R regulation circuit can be directly controlled by the enable switch K1. When the satellite works in a normal illumination orbit, K1 is enabled; when the satellite works in an illumination-earth shadow orbit, K1 is disabled.

[0067] When the enable switch K1 is enabled, the BEA signal controls the state of transistors Q1 and Q2; when the BEA signal outputs a high level, transistors Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit fails and is locked to a low level, and the PWM signal output by the S3R regulation circuit continues to be a high level, forcing the output of the power stabilization module circuit to be turned off; when the BEA signal outputs a low level, transistors Q1 and Q2 are turned off, the fixed voltage signal in the domain circuit is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power, thereby realizing the battery pack charging function;

[0068] In the present invention, the transistors Q1 and Q2 are connected in series, and after Q2 is saturated and turned on, Q1 is also saturated and turned on, which can effectively avoid the failure of a single transistor and improve the reliability of the circuit.

[0069] Example

[0070] See also Figure 1 , Figure 2 and Figure 3 , a structural block diagram and principle diagram of a circuit for solving the trickle charging of the S3R power supply system under normal light conditions in this embodiment.

[0071] When the satellite enters the constant illumination orbit, turn on the enable switch K1. The hysteresis comparison circuit is actually a hysteresis comparator. By adjusting R1, R2 and R3, the hysteresis interval of the battery voltage during the constant illumination period can be adjusted to be lower than the bus charging final voltage VBUS, so as to keep the charging process always charged with a high current. th -,VB th+ ], according to Kirchhoff's law,

[0072] R3=min{(VCC-Vref) / I R3 ,Vref / I R3},

[0073] Among them I R3 >100I IB ,I IB is the input bias current of the comparator;

[0074] R1=R3*(VB th+ -VB th -) / VCC;

[0075] R2=1 / (VB th+ / (Vref*R1)-1 / R1-1 / R3).

[0076] The battery voltage sampling signal is compared with the reference Vref hysteresis to generate a BEA signal. When the battery voltage is lower than the set value lower limit VB th -, the BEA signal continuously outputs a low level, the transistors Q1 and Q2 are cut off, the fixed voltage signal in the domain circuit is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power to realize the battery pack charging; when the battery voltage continues to rise to the set value upper limit VB th+ When the BEA signal outputs a high level, transistors Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit is locked to a low level, and the S3R regulation circuit controls the power stabilization module circuit to turn off the power output, that is, turn off the charging function of the battery pack, and the battery enters the discharge state to maintain the rear-end load, and the battery voltage continues to decrease to the set value VB th-, it enters the next cycle, which can ensure that the battery is always in charging and discharging conditions during normal light exposure, effectively avoiding trickle charging of the S3R power system under normal light conditions.

[0077] In this embodiment, the final voltage of the primary busbar charging is 28.5V. After entering the constant illumination orbit, the satellite determines the battery charging according to the load condition, turns on the enabling switch K1, and adjusts R1, R2 and R3 to meet the set battery voltage hysteresis interval [VB th ,VB th+ ]=[27V,28V].

[0078] K1 can choose the domestic 891 factory magnetic latching relay JMW-270M, the contact life can reach 100,000 times, the contact parallel design is adopted, the reliability is good, it is suitable for the frequent switching of the normal light track and the light-ground shadow track, and ensures that the battery works in a safe state.

[0079] During the battery charging process, when the battery voltage is lower than 28V, Q1 and Q2 are turned off, the fixed voltage signal in the domain circuit is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power to realize the battery pack charging; when the battery voltage is higher than 28V, Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit is locked to a low level, and the S3R regulation circuit controls the power stabilization module circuit to turn off the power output, that is, turn off the charging function of the battery pack, and the battery enters the discharge state. When the battery is discharged to a voltage lower than 27V, Q1 and Q2 are turned off and enter the next cycle again. Ensure that the battery is always in the charging and discharging process during the normal light period, and effectively avoid the trickle charging of the S3R power system under normal light conditions.

[0080] Although the contents of the present invention have been described in detail through the above-mentioned preferred embodiments, it should be recognized that the above description should not be regarded as limiting the present invention, and other changes and modifications made by technicians in this field without departing from the spirit and scope of protection of the present invention are still included in the scope of protection of the present invention.

Claims

1. A circuit for solving the trickle charging of S3R power supply system under normal light conditions, characterized in that include: Reference circuit, battery voltage divider circuit, hysteresis comparison circuit, MEA circuit, operational amplifier circuit, S3R regulation circuit, power stabilization module circuit, enable switch control circuit and domain signal locking circuit; wherein: A reference circuit outputs a reference voltage to a hysteresis comparison circuit; A battery voltage divider circuit outputs a battery voltage signal to a hysteresis comparison circuit; The hysteresis comparator circuit compares the battery voltage signal with the reference signal. When the battery voltage signal is lower than the set battery voltage lower limit VB th- When the BEA signal formed by the hysteresis comparison circuit outputs a low level, the transistors Q1 and Q2 in the domain signal locking circuit are turned off, the domain signal is unlocked to the initial setting value, and the S3R regulation circuit charges the battery pack; when the battery voltage signal is higher than the set battery voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparison circuit outputs a high level, the transistors Q1 and Q2 in the domain signal locking circuit are turned on, the domain signal is locked to a low level, and the S3R regulation circuit stops charging the battery pack by regulating the power stabilization module circuit; The enabling switch control circuit controls the on and off state through external instructions to realize whether the BEA signal is connected to the domain signal locking circuit; The sub-domain signal locking circuit, when the enabling switch control circuit is turned on, when the BEA signal is at a high level, the sub-domain signal is locked to a low level; when the BEA signal is at a low level, the sub-domain signal is locked to an initial setting value; the sub-domain signal is sent to the operational amplifier circuit; The power stabilization module circuit is connected to the battery pack to realize the charging function of the battery pack; The MEA circuit performs error amplification on the output power VBUS of the power stabilization module circuit, and sends the output MEA signal to the operational amplifier circuit; An operational amplifier circuit performs differential amplification on the MEA signal and the sub-domain signal, and the output end is connected to the S3R regulation circuit; The S3R regulation circuit outputs a PWM control signal to control the output power of the power stabilization module circuit and complete the battery pack charging function; The domain signal locking circuit includes a domain circuit, NPN transistors Q1 and Q2; The domain division circuit generates a constant reference voltage, namely the domain division signal, which is fed into the negative input terminal of the operational amplifier circuit; the collector of transistor Q1 is connected to the domain division circuit, the emitter of transistor Q1 is connected to the collector of transistor Q2, the bases of transistors Q1 and Q2 are connected, and are also connected to the output terminal of the magnetic latching relay K1, and the collector of transistor Q2 is connected to the signal ground wire.

2. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 1, characterized in that: The reference circuit Vref is a fixed voltage value and uses a voltage regulator to generate a standard voltage signal.

3. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 2, characterized in that: The battery voltage dividing circuit includes resistors R1 and R2; One end of the resistor R1 is connected to the battery pack voltage sampling signal VBAT, and the other end is connected in series with the resistor R2. The other end of R2 is connected to the battery sampling ground line. The connection point between R1 and R2 is connected to the hysteresis comparison circuit as the battery voltage sampling signal.

4. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 2, characterized in that: The hysteresis comparison circuit includes a comparator working power supply VCC, resistors R3, R4, R5, and a comparator; The two ends of the resistor R3 are respectively connected across the in-phase terminal and the output terminal of the comparator; One end of the resistor R4 is connected to the comparator working power supply VCC, and the other end is connected to the comparator power input port; One end of the resistor R5 is connected to the comparator working power supply VCC, and the other end is connected to the signal output port of the comparator; The output signal of the reference circuit Vref is connected to the inverting terminal of the comparator; The output of the comparator is the BEA signal.

5. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 4, characterized in that: The enabling switch control circuit includes a magnetic latching relay K1.

6. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 1, characterized in that: When the satellite enters the constant illumination orbit, the magnetic latching relay K1 is turned on, and the hysteresis comparison circuit compares the battery voltage sampling signal with the reference signal Vref to generate a BEA signal to control the state of transistors Q1 and Q2. During the charging process, when the battery voltage is lower than the set value VB th- When the BEA signal formed by the hysteresis comparator is low level, the transistors Q1 and Q2 are cut off, and the domain signal is valid at this time. The S3R regulation circuit controls the power stabilization module circuit to output full power, realizing the battery pack charging function; The battery voltage continues to rise to the set charging voltage upper limit VB th+ When the BEA signal formed by the hysteresis comparator is high, the transistors Q1 and Q2 are saturated and turned on. At this time, the domain signal fails and is locked at a low level. The PWM signal output by the S3R regulation circuit continues to be high, and the power stabilization module circuit is controlled to turn off the power output, that is, turn off the charging function of the battery pack, effectively avoiding trickle charging of the S3R power system under normal light conditions.

7. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 4, characterized in that: Adjust the resistors R1, R2 and R3 to adjust the hysteresis range of the battery voltage [VB th- ,VB th+ ] so that its upper and lower limits are lower than the bus charging final voltage VBUS under normal conditions.

8. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 6, characterized in that: Whether the BEA signal effectively participates in the S3R regulation circuit is directly controlled by the magnetic latching relay K1. The satellite works in a constant illumination orbit and K1 is enabled; The satellite operates in a light-shadow orbit, K1 is prohibited.

9. A circuit for solving trickle charging of S3R power supply system under normal light conditions according to claim 8, characterized in that: When the magnetic latching relay K1 is enabled, the BEA signal controls the state of transistors Q1 and Q2; when the BEA signal outputs a high level, transistors Q1 and Q2 are saturated and turned on, the fixed voltage signal in the domain circuit fails and is locked to a low level, and the PWM signal output by the S3R regulation circuit is continuously at a high level, forcing the output of the power stabilization module circuit to be turned off; when the BEA signal outputs a low level, transistors Q1 and Q2 are turned off, the fixed voltage signal in the domain circuit is valid, and the S3R regulation circuit controls the power stabilization module circuit to output full power, realizing the battery pack charging function; Transistors Q1 and Q2 are used in series. After Q2 is saturated and turned on, Q1 is also saturated and turned on, which can effectively avoid the failure of a single transistor and improve the reliability of the circuit.

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