A high-reliability charging and discharging circuit for aerospace

Abstract

The present invention discloses a high-reliability aerospace charging and discharging circuit, comprising: an isolation diode 1, an isolation diode 2, an isolation diode 3, a discharge switch, a battery pack, a charging switching switch, a sampling resistor and a charging switch. The circuit includes a discharge path and a charging path, and can meet the requirements of 80A discharge current output and 18A charging current. The charging and discharging of the battery can be realized in an unregulated manner, which can reduce the number of regulating modules and reduce the size and weight of the power controller. Through the reasonable configuration of the isolation diode and the charging and discharging switch, the reliability of the charging and discharging circuit can be improved, the risk of circuit failure can be reduced, and it is suitable for long-life, high-reliability, and lightweight spacecraft.

Description

Technical Field

[0001] The invention relates to the technical field of space power supply, and in particular to an aerospace high-reliability charging and discharging circuit. Background Art

[0002] In the aerospace power supply system, the battery pack is an important energy storage device, which provides power to the spacecraft by discharging during the launch phase, mission phase, and shadow period of the spacecraft. As the path of the battery, the charge and discharge circuit plays a vital role in ensuring the normal function of the battery pack. At present, the commonly used charge and discharge circuits in aerospace systems are full-regulation mode and unregulated mode. Among them, the full-regulation mode requires a corresponding regulation circuit, and its volume and weight may account for 1 / 3 to 1 / 2 of the entire power controller. Its advantage is that the voltage point is fixed, and it can be selected for spacecraft with relatively high bus voltage requirements and surplus volume and weight. However, for most spacecraft, reducing volume and weight is very important, and the unregulated charge and discharge circuit can achieve the charge and discharge function of the battery through a combination of switches and diodes, which can greatly reduce the volume and weight of the controller.

[0003] The present invention aims at the above-mentioned battery charging and discharging problem and proposes a high-reliability aerospace charging and discharging circuit. The switching between two charging modes and two discharging modes is realized by a relay, which can meet the requirements of maximum 80A discharge and 18A charging. The high reliability of the charging and discharging circuit is achieved by the reasonable configuration of diodes, relays and MOS tubes. The present invention is suitable for spacecraft with long life and high power density requirements. Summary of the invention

[0004] The purpose of the present invention is to provide a high-reliability charging and discharging circuit for aerospace, which solves the demand for large current charging and discharging through the reasonable configuration of diodes, relays and MOS tubes, and the high-reliability circuit design can meet the characteristics of aerospace.

[0005] In order to achieve the above-mentioned purpose, the present invention provides an aerospace high-reliability charging and discharging circuit, comprising: an isolation diode 11, an isolation diode 22, a discharge switch 3, a battery pack 4, a charging switching switch 5, an isolation diode 36, a sampling resistor 7 and a charging switch 8;

[0006] The cathode of the isolation diode 11 is connected to the low voltage bus, and the anode is connected to the cathode of the isolation diode 22 and the 2nd port of the charging switch 5;

[0007] The cathode of the isolation diode 22 is connected to the anode of the isolation diode 11 and the port 2 of the charging switch 5, and the anode is connected to the port 3 of the discharging switch 3;

[0008] The 1st port of the discharge switch 3 is connected to the positive terminal of the battery pack 4 and the D terminal of the charging switch 8, the 3rd port is connected to the positive electrode of the isolation diode 22, and the 2nd port is connected to the common terminal of the sampling resistor 7 and the S terminal of the charging switch 8;

[0009] The positive end of the battery pack 4 is connected to the 1 port of the discharge switch 3 and the D end of the charging switch 8, and the negative end is connected to the low-voltage bus -;

[0010] Port 1 of the charging switch 5 is connected to the low voltage bus +, port 2 is connected to the cathode of the isolation diode 22 and the anode of the isolation diode 11, and port 3 is connected to the anode of the isolation diode 36;

[0011] The positive electrode of the isolation diode 36 is connected to the 3-port of the charging switch 5, and the negative electrode is connected to the sampling resistor 7;

[0012] One end of the sampling resistor 7 is connected to the cathode of the isolation diode 36, and the other end is connected to the S end of the charging switch 8 and the 2 port of the discharging switch 3;

[0013] The D end of the charging switch 8 is connected to the positive end of the battery pack 4, and the S end is connected to the sampling resistor 7 and the 2 end of the discharge switch 3.

[0014] There are two discharge paths, one is a small current discharge path, and the other is a large current discharge path;

[0015] The small current discharge path is battery pack 4 → discharge switch 3 → isolation diode 22 → isolation diode 11 → low voltage bus +;

[0016] The high current discharge path is battery pack 4 → discharge switch 3 → isolation diode 22 → charging switch 5 → low voltage bus +,

[0017] There are two charging paths, one is a normal charging path, and the other is an over-discharge charging path;

[0018] The conventional charging path is low voltage bus +→ charging switch 5→isolating diode 36→sampling resistor 7→charging switch 8→battery pack 4;

[0019] The over-discharge charging path is low voltage bus +→charging switch 5→isolating diode 36→sampling resistor 7→discharging switch 3→battery pack 4.

[0020] The above-mentioned aerospace high-reliability charging and discharging circuit, wherein the isolation diode 11 includes 6 power diodes connected in parallel in the same direction. When one diode is open-circuited, the current passes through the other 5 diodes without affecting its discharge function; when one diode is short-circuited, due to the presence of the isolation diode 22, the flow direction of the current can still be limited.

[0021] The above-mentioned aerospace high-reliability charging and discharging circuit, wherein the isolation diode 22 includes 10 power diodes connected in parallel in the same direction. When one diode is open, the current passes through the other 9 diodes without affecting its discharge function; when one diode is short-circuited, since the charging switching switch 5 can be switched to the charging state, it still does not affect the unidirectional conductivity of the discharge path.

[0022] The above-mentioned aerospace high-reliability charging and discharging circuit, wherein the discharge switch 3 includes two redundant parallel relays. When a certain relay has contact adhesion and is in the normally on state, there is no impact because the discharge does not affect the detector state under normal circumstances; when it is in the normally off state, since a single relay can meet the current demand, it does not affect the normal discharge of the battery pack.

[0023] The above-mentioned aerospace high-reliability charging and discharging circuit, wherein the charging switching switch 5 includes two redundant parallel relays. When the contacts of one of the relays are stuck and it is normally on, since the charging path is determined by the charging switching switch 5, the charging switch 8 or the discharging switch 3, as long as the charging switch 8 is disconnected and the discharging switch 3 is in the discharging state, there is no impact; when it is normally off, since a single relay can meet the current demand, it does not affect the normal charging of the battery pack.

[0024] In the above-mentioned aerospace high-reliability charging and discharging circuit, the isolation diode 36 includes 6 power diodes arranged in the same direction, and the 6 power diodes are distributed in such a way that three are connected in parallel and then two are connected in series. The short circuit and open circuit of the power diodes do not affect the unidirectional conductivity of the charging path.

[0025] In the above-mentioned aerospace high-reliability charging and discharging circuit, the sampling resistor 7 includes 5 sampling resistors. When one of the resistors is open-circuited, the voltage drop on the sampling resistor will increase by 20%, and the corresponding charging current value will decrease by 20%, which has little effect.

[0026] The charging switch 8 comprises three MOS tubes. When one MOS tube is open-circuited, the current can flow through the other two MOS tubes without much impact. When one MOS tube is short-circuited, the charging switch 5 is switched to the discharge mode to disconnect the charging mode, thereby preventing the battery from floating.

[0027] The above-mentioned aerospace high-reliability charging and discharging circuit includes two paths: a discharging path and a charging path, wherein the discharging path can provide a maximum current of 80A for the low-voltage bus, and the charging path can provide a maximum charging current of 18A for the battery pack.

[0028] Compared with the prior art, the technical benefits of the present invention are:

[0029] (1) The present invention aims at the high-power discharge demand of the aerospace power supply system, and realizes the high-current charging and discharging demand of the battery by adopting the non-adjustment mode with reasonable configuration of relays, diodes and MOS tubes, which greatly reduces the volume and weight of the circuit.

[0030] (2) The reliability design of the present invention can meet the reliability requirements of the first-level fault protection function of aerospace. In the event of a failure of any device in the charge and discharge circuit, the battery can still be charged and discharged normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] An aerospace high-reliability charging and discharging circuit of the present invention is provided by the following embodiments and drawings.

[0032] Figure 1 This is a topological diagram of the present invention.

[0033] Among them, 1-isolation diode 1, 2-isolation diode 2, 3-discharge switch, 4-battery pack, 5-charge switching switch, 6-isolation diode 3, 7-sampling resistor, 8-charging switch. DETAILED DESCRIPTION

[0034] The following is a further detailed description of an aerospace high-reliability charging and discharging circuit of the present invention in conjunction with the accompanying drawings.

[0035] The technical solution of the present invention is: an aerospace high-reliability charging and discharging circuit, including an isolation diode 11, an isolation diode 22, a discharge switch 3, a battery pack 4, a charging switching switch 5, an isolation diode 36, a sampling resistor 7 and a charging switch 8.

[0036] It includes two paths: a discharge path and a charge path. The discharge path can provide a maximum current of 80A for the low-voltage bus; the charge path can provide a maximum charging current of 18A for the battery pack.

[0037] Through the reasonable configuration of devices, the circuit can still ensure the circuit function of the charging and discharging circuit in the event of a serious failure of any device in the charging and discharging path, and has high reliability.

[0038] The isolation diode 11 includes 6 diodes connected in parallel in the same direction, with the negative pole connected to the low-voltage bus, and the positive pole connected to the isolation diode 22 and the 2nd port of the charging switch 5, which is used to limit the discharge current from the battery to the low-voltage bus for small current discharge;

[0039] The isolation diode 22 includes 10 diodes connected in parallel in the same direction. The negative pole is connected to the positive pole of the isolation diode 11 and the port 2 of the charging switching switch 5, and the positive pole is connected to the port 3 of the discharge switch. Its function is to limit the discharge current from the battery to the low-voltage bus. All discharge currents will pass through the isolation diode 22.

[0040] The discharge switch 3 includes two redundant parallel relays, port 1 is connected to the positive terminal of the battery pack and the D terminal of the charging switch 8, port 3 is connected to the positive electrode of the isolation diode 22, and port 2 is connected to the common terminal of the sampling resistor 7 and the S terminal of the charging switch 8. Its function is to select whether to enter the discharge state on the one hand, and to provide a charging path under special circumstances on the other hand;

[0041] The battery pack 4 has a positive end connected to the 1 port of the discharge switch 3 and the D terminal of the charging switch 8, and a negative end connected to the low-voltage bus -. Its function is to store energy when the low-voltage bus power is sufficient, and release electric energy when the low-voltage bus power is insufficient;

[0042] The charging switch 5 includes two redundant parallel relays, port 1 is connected to the low voltage bus +, port 2 is connected to the cathode of the isolation diode 22 and the anode of the isolation diode 11, and port 3 is connected to the anode of the isolation diode 36. Its function is to select the discharge path or the charging path;

[0043] The isolation diode 36 includes 6 diodes arranged in the same direction, the positive electrode of which is connected to the 3-port of the charging switch 5, and the negative electrode of which is connected to the sampling resistor 7. Its function is to limit the current from the low-voltage bus to the battery;

[0044] The sampling resistor 7 has one end connected to the cathode of the isolation diode 36 and one end connected to the S end of the charging switch 8 and the 2 port of the discharging switch 3, and its function is to obtain the charging current by calculating the voltage drop across the two ends of the sampling resistor;

[0045] The charging switch 8 has a D terminal connected to the positive terminal of the battery pack and an S terminal connected to the sampling resistor 7 and the 2nd port of the discharge switch 3. Its function is to select whether to enter the charging state.

[0046] There are two discharge paths, one is a small current discharge path, and the other is a large current discharge path;

[0047] The small current discharge path is battery pack 4 → discharge switch 3 → isolation diode 22 → isolation diode 11 → low voltage bus +;

[0048] The high current discharge path is battery pack 4 → discharge switch 3 → isolation diode 22 → charging switch 5 → low voltage bus +;

[0049] There are two charging paths, one is a normal charging path, and the other is an over-discharge charging path;

[0050] The conventional charging path is low voltage bus +→charging switch 5→isolating diode 36→sampling resistor 7→charging switch 8→battery pack 4;

[0051] The over-discharge charging path is low voltage bus +→charging switch 5→isolation diode 36→sampling resistor 7→discharging switch 3→battery pack 4;

[0052] The device failure contents include: isolation diode 11 open circuit and short circuit, isolation diode 22 open circuit and short circuit, discharge switch 3 is normally off and normally open, charging switching switch 5 is normally off and normally open, isolation diode 36 is open circuit and short circuit, sampling resistor 7 is open circuit, and charging switch 8 is open circuit and short circuit.

[0053] The isolation diode 11 has a total of 6 power diodes connected in parallel in the same direction. When one diode is open, the current passes through the other 5 diodes without affecting its discharge function; when one diode is short-circuited, the flow of current can still be limited due to the existence of the isolation diode 22.

[0054] The isolation diode 22 has a total of 10 power diodes connected in parallel in the same direction. When one diode is open, the current passes through the other 9 diodes without affecting its discharge function; when one diode is short-circuited, the charging switching switch 5 can be switched to the charging state, which still does not affect the unidirectional conductivity of the discharge path.

[0055] The discharge switch 3 has two redundant parallel relays. When one of the relays has contact adhesion and is normally on, there is no impact because the detector state is not affected when the discharge is normally on under normal circumstances; when it is normally off, the normal discharge of the battery pack is not affected because a single relay can meet the current demand.

[0056] The charging switching switch 5 has a total of 2 redundant parallel relays. When the contacts of one of the relays are stuck and it is normally on, since the charging path is determined by the charging switching switch 5, the charging switch 8 or the discharging switch 3, there will be no impact as long as the charging switch 8 is disconnected and the discharging switch 3 is in the discharging state; when it is normally off, since a single relay can meet the current demand, it will not affect the normal charging of the battery pack.

[0057] The isolation diode 36 has a total of 6 power diodes arranged in the same direction. The 6 power diodes are distributed as three in parallel and two in series, that is, every three are connected in parallel and then two groups are connected in series. The short circuit and open circuit of the power diodes do not affect the unidirectional conductivity of the charging path.

[0058] The sampling resistor 7 has a total of 5 sampling resistors. When one of the resistors is open-circuited, the voltage drop on the sampling resistor will increase by 20%, and the corresponding charging current value will decrease by 20%, which has little effect.

[0059] The charging switch 8 has a total of three MOS tubes. When one MOS tube is open-circuited, the current can flow through the other two MOS tubes, and the impact is not significant. When a MOS tube is short-circuited, the charging switch 5 is switched to the discharge mode to disconnect the charging mode to prevent the battery from floating.

Claims

1. An aerospace high-reliability charging and discharging circuit, characterized in that: include: Isolation diode 1 (1), isolation diode 2 (2), discharge switch (3), battery pack (4), charging switch (5), isolation diode 3 (6), sampling resistor (7) and charging switch (8); The cathode of the isolation diode 1 (1) is connected to the low voltage bus, and the anode is connected to the cathode of the isolation diode 2 (2) and port 2 of the charging switch (5); The cathode of the isolation diode 2 (2) is connected to the anode of the isolation diode 1 (1) and the port 2 of the charging switch (5), and the anode is connected to the port 3 of the discharging switch (3); Port 1 of the discharge switch (3) is connected to the positive terminal of the battery pack (4) and the D terminal of the charging switch (8), port 3 is connected to the positive electrode of the isolation diode 2 (2), and port 2 is connected to the common terminal of the sampling resistor (7) and the S terminal of the charging switch (8); The positive end of the battery pack (4) is connected to the 1 port of the discharge switch (3) and the D end of the charge switch (8), and the negative end is connected to the low-voltage busbar -; Port 1 of the charging switch (5) is connected to the low voltage bus +, port 2 is connected to the cathode of the isolation diode 2 (2) and the anode of the isolation diode 1 (1), and port 3 is connected to the anode of the isolation diode 3 (6); The positive electrode of the isolation diode 3 (6) is connected to the 3-port of the charging switch (5), and the negative electrode is connected to the sampling resistor (7); One end of the sampling resistor (7) is connected to the negative electrode of the isolation diode 3 (6), and the other end is connected to the S end of the charging switch (8) and the 2 port of the discharging switch (3); The D end of the charging switch (8) is connected to the positive end of the battery pack (4), and the S end is connected to the sampling resistor (7) and the 2-port of the discharge switch (3). There are two discharge paths, one is a small current discharge path, and the other is a large current discharge path; The small current discharge path is battery pack (4) → discharge switch (3) → isolation diode 2 (2) → isolation diode 1 (1) → low voltage bus +; The high current discharge path is battery pack (4) → discharge switch (3) → isolation diode 2 (2) → charging switch (5) → low voltage bus +, There are two charging paths, one is a normal charging path, and the other is an over-discharge charging path; The conventional charging path is low voltage bus +→ charging switch (5)→isolation diode 3 (6)→sampling resistor (7)→charging switch (8)→battery pack (4); The over-discharge charging path is low voltage bus +→ charging switching switch (5)→isolating diode 3 (6)→sampling resistor (7)→discharging switch (3)→battery pack (4).

2. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The isolation diode 1 (1) comprises six power diodes connected in parallel in the same direction. When one diode is open-circuited, the current passes through the other five diodes without affecting their discharge function. When one diode is short-circuited, the flow of current can still be limited due to the presence of the isolation diode 2 (2).

3. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The isolation diode 2 (2) comprises 10 power diodes connected in parallel in the same direction. When one of the diodes is open-circuited, the current passes through the other 9 diodes without affecting their discharge function. When one of the diodes is short-circuited, the charging switching switch (5) can be switched to the charging state, which still does not affect the unidirectional conductivity of the discharge path.

4. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The discharge switch (3) comprises two redundant parallel relays. When a contact of one of the relays is stuck and is in a normally on state, there is no impact because discharge does not affect the detector state under normal circumstances; when the discharge switch (3) is in a normally off state, a single relay can meet the current demand, so the normal discharge of the battery pack is not affected.

5. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The charging switch (5) comprises two redundant parallel relays. When a contact of a certain relay is stuck and is in a normally open state, since the charging path is determined by the charging switch (5), the charging switch (8) or the discharging switch (3), there is no impact as long as the charging switch (8) is disconnected and the discharging switch (3) is in a discharging state; when it is in a normally open state, since a single relay can meet the current demand, it does not affect the normal charging of the battery pack.

6. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The isolation diode 3 (6) includes 6 power diodes arranged in the same direction. The 6 power diodes are arranged in such a way that three diodes are connected in parallel and then two diodes are connected in series. The short circuit and open circuit of the power diodes do not affect the unidirectional conductivity of the charging path.

7. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: The sampling resistor (7) includes 5 sampling resistors. When one of the resistors is open-circuited, the voltage drop on the sampling resistor will increase by 20%, and the corresponding charging current value will decrease by 20%, which has little impact. The charging switch (8) comprises three MOS tubes. When an open circuit occurs in one MOS tube, the current can flow through the other two MOS tubes, and the impact is not significant. When a short circuit occurs in one MOS tube, the charging switching switch (5) is switched to the discharge mode, and the charging mode can be disconnected to prevent the battery from floating charge.

8. The aerospace high-reliability charging and discharging circuit according to claim 1, characterized in that: It includes two paths: a discharge path and a charge path. The discharge path can provide a maximum current of 80A for the low-voltage bus, and the charge path can provide a maximum charging current of 18A for the battery pack.

Images