Circuit protection device based on AGV non-stop charging

Abstract

The utility model discloses a circuit protection device based on AGV non-stop charging, which comprises a control circuit board SAC, a load, a first battery pack B1, a second battery pack B2 and a charger J1, and the output end of the charger J1 is electrically connected with the input end of the first battery pack B1 and the input end of the second battery pack B2. The output end of the first battery pack B1 and the output end of the second battery pack B2 are electrically connected with the input end of the control circuit board SAC, the output end of the control circuit board SAC is electrically connected with the input end of the load, and the output end of the charger J1 is provided with a protection circuit used for protecting a line when the line breaks down. According to the utility model, the problem in the prior art that a traditional battery management system is easy to damage a control circuit during charging is solved. The device has the advantages of being high in safety and stability and the like.

Description

Technical Field

[0001] The utility model relates to the field of circuit protection device structures, and more specifically, to a circuit protection device based on non-stop charging of AGV. Background Art

[0002] Lithium batteries have the characteristics of light weight, high energy density, strong adaptability, etc., but at the same time, they also have the disadvantages of high price and high requirements for voltage and current. Due to the limitation of charging time, the battery often needs to withstand high-power charging during the normal operation of the AGV system, and the high requirements of lithium batteries for charging voltage and current make the BMS system of the battery more likely to be protected from overheating and unstable voltage during high-power charging.

[0003] When the BMS system of the lithium battery protects the battery, it will cut off the battery circuit. However, if the device is not shut down and is charging at this time, due to the existence of the power consumption circuit, the charging circuit cannot detect in time that the battery circuit is cut off, and the rapid decrease of the power consumption load will cause the charging voltage to rise sharply, resulting in damage to some high-voltage-intolerant components on the circuit board. Since this process occurs in an extremely short time, traditional protection measures cannot achieve good results. The response time of the contactor to cut off the circuit is 5 - 15 ms.

[0004] At present, a control circuit of a battery management system, a battery management system and an electronic device are disclosed on the Chinese Patent Network, with the publication number CN215378508U. Among them, the control circuit of the battery management system includes a switch unit, a current limiting unit and an isolation unit; the first end of the switch unit is connected to the positive pole of the battery, and the second end of the switch unit is connected to the first end of the input side of the isolation unit through the current limiting unit; the first end of the output side of the isolation unit is connected to the power supply voltage input end of the battery management system, and the second end of the output side of the isolation unit is connected to the enable end of the battery management system; the switch unit closes when receiving a control signal, so that the isolation unit is turned on and an enable signal is output to the battery management system. The charging and discharging process of the battery pack is controlled through the battery management system, and a control circuit including a switch unit, a current limiting unit and an isolation unit is set to control the power consumption of the battery management system during the standby process, so as to solve the problem of large power consumption generated by the battery management system in the standby state.

[0005] For a control circuit of a battery management system, a battery management system and an electronic device in the above patent, since there is no device for protecting the circuit when the battery has an abnormality during charging, the battery system is likely to generate a large current during charging, causing great damage to the control circuit. Summary of the Utility Model

[0006] In order to overcome the problem in the prior art that the traditional battery management system is prone to damage the control circuit during charging, the present utility model provides a circuit protection device based on AGV non-stop charging, which has a function of protecting the control circuit.

[0007] A circuit protection device based on AGV non-stop charging of the present utility model includes a control circuit board SAC, a load, a first battery pack B1, a second battery pack B2 and a charger J1. The output end of the charger J1 is electrically connected to the input ends of the first battery pack B1 and the second battery pack B2 respectively. The output ends of the first battery pack B1 and the second battery pack B2 are electrically connected to the input end of the control circuit board SAC respectively. The output end of the control circuit board SAC is electrically connected to the input end of the load. A protection circuit for protecting the circuit when a fault occurs in the line is provided on the output end of the charger J1.

[0008] The present utility model connects two single battery packs in parallel. When one of the battery packs is abnormally cut off by the protection circuit, the other battery pack plays a buffering role. Most of the output of the charger will pass through this battery pack, and the phenomenon of sharp voltage rise will disappear. At the same time, the current detection device at the front end of each battery pack will detect the magnitude of the current and can cut off the main power supply circuit to protect the SAC circuit board. The probability that the BMS is triggered by both battery packs at the same time is extremely low. Even if the protection is triggered simultaneously, there will be a time difference, and within this time difference, it is sufficient for the contactor to cut off the main power supply circuit. At the same time, because there are two battery packs, after the main charging circuit is cut off, the other battery pack can ensure the power supply of the electrical equipment and improve the stability of the AGV system.

[0009] Preferably, the protection circuit includes a current sensor CT1, a current sensor CT2, an electromagnetic contactor MC1, an electromagnetic contactor MC2, a diode D1, a diode D2, a diode D3, a diode D4, and a comparison circuit. The 1-pin of the charger J1 is the N-pole contact. The 2-pin of the charger J1 is electrically connected to one end of the electromagnetic contactor MC2. The other end of the electromagnetic contactor MC2 is electrically connected to one end of the current sensor CT1 and one end of the current sensor CT2 respectively. The other end of the current sensor CT1 is the P1-pole contact. The other end of the current sensor CT2 is the P2-pole contact. The coil control end of the electromagnetic contactor MC2 is electrically connected to the signal output end of the comparison circuit. The signal output ends of the current sensor CT1 and the current sensor CT2 are respectively electrically connected to the signal input ends of the comparison circuit. The N-pole contact is electrically connected to the negative electrodes of the first battery pack B1, the second battery pack B2, the control circuit board SAC, and the load respectively. The P1-pole contact is electrically connected to the positive electrode of the diode D1. The P2-pole contact is electrically connected to the positive electrode of the diode D2. The negative electrode of the diode D1 is electrically connected to the positive electrode of the diode D3 and the positive electrode of the first battery pack B1 respectively. The negative electrode of the diode D2 is electrically connected to the positive electrode of the diode D4 and the positive electrode of the second battery pack B2 respectively. The negative electrodes of the diode D3 and the diode D4 are electrically connected to the positive electrode of the control circuit board SAC respectively. The positive electrode of the control circuit board SAC is electrically connected to one end of the electromagnetic contactor MC1. The other end of the electromagnetic contactor MC1 is electrically connected to the positive electrode of the load. The coil control end of the electromagnetic contactor MC1 is electrically connected to the signal output end of the control circuit board SAC.

[0010] The diodes D1 and D3 are used to prevent current backflow when an abnormality occurs during the charging of the first battery pack B1, and the diodes D2 and D4 are used to prevent current backflow when an abnormality occurs during the charging of the second battery pack B2, improving the safety and stability of the present invention.

[0011] Preferably, the comparison circuit includes an operational amplifier chip CP1, an operational amplifier chip CP2, an exclusive-OR gate OR, an AND gate AND, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor Ri1, a resistor Ri2, a resistor Rref1, a resistor Rref2, a capacitor C1, a capacitor C2, and a reference circuit. One pin of the operational amplifier chip CP1 is electrically connected to one end of the resistor Ri1 and one end of the resistor Rref1. The other end of the resistor Ri1 is electrically connected to the signal output end of the current sensor CT1. The other end of the resistor Rref1 is electrically connected to the 5th pin of the operational amplifier chip CP1 and one end of the resistor R1. The other end of the resistor R1 is connected to VCC. The other end of the resistor R1 is electrically connected to the 4th pin of the operational amplifier chip CP1 and one end of the resistor R2. The other end of the resistor R2 is electrically connected to one end of the capacitor C1. The other end of the capacitor C1 is electrically connected to the 2nd pin and the 3rd pin of the operational amplifier chip CP1. The 3rd pin of the operational amplifier chip CP1 is grounded. The other end of the resistor R2 is electrically connected to the 1st pin of the exclusive-OR gate OR. One pin of the operational amplifier chip CP2 is electrically connected to one end of the resistor Ri2 and one end of the resistor Rref2. The other end of the resistor Ri2 is electrically connected to the signal output end of the current sensor CT2. The other end of the resistor Rref2 is electrically connected to the 5th pin of the operational amplifier chip CP2 and one end of the resistor R3. The other end of the resistor R3 is connected to VCC. The other end of the resistor R3 is electrically connected to the 4th pin of the operational amplifier chip CP2 and one end of the resistor R4. The other end of the resistor R4 is electrically connected to one end of the capacitor C2. The other end of the capacitor C2 is electrically connected to the 2nd pin and the 3rd pin of the operational amplifier chip CP2. The 3rd pin of the operational amplifier chip CP2 is grounded. The other end of the resistor R4 is electrically connected to the 2nd pin of the exclusive-OR gate OR. The 3rd pin of the exclusive-OR gate OR is electrically connected to the 1st pin of the AND gate AND. The 3rd pin of the AND gate AND is electrically connected to the coil control end of the electromagnetic contactor MC2. The output end of the reference circuit is electrically connected to the 2nd pin of the AND gate AND.

[0012] The charger J1 can be of the model: ACU2-6050; the control circuit board SAC can be of the model: SAC-04-02; the first battery pack B1 and the second battery pack B2 can both be of the model: ALM12V7SHP; the VCC is +12V; the operational amplifier chips CP1 and CP2 can both be of the model M8914; the electromagnetic contactors MC1 and MC2 can both be of the model: ICON DC electromagnetic contactor; the current sensors CT1 and CT2 can both be of the model: CHB-25NP.

[0013] The described reference circuit is provided by charger J1, that is, pin 2 of AND gate AND is electrically connected to the regulated output terminal of charger J1.

[0014] During operation, when the battery of the AGV is abnormal, the present utility model can protect the SAC circuit board in time. The present utility model uses a first battery pack B1 and a second battery pack B2, and connects the two independent battery packs in parallel. Diodes are added to each battery to prevent reverse current. At the same time, a current sensor is added to each charging circuit of each battery pack, and comparison and analysis are carried out through a comparison circuit, and a contactor is added to the total charging circuit.

[0015] During the charging process of the first battery pack B1 and the second battery pack B2, current sensor CT1 converts the collected current data into voltage data Vct1 and sends it to the comparison circuit, and current sensor CT2 converts the collected current data into voltage data Vct2 and sends it to the comparison circuit. In the comparison circuit, the amplifier circuit with operational amplifier chip CP1 as the core will amplify Vct1 and output voltage signal V02 and send it to exclusive-OR gate OR. In the comparison circuit, the amplifier circuit with operational amplifier chip CP2 as the core will amplify Vct2 and output voltage signal V04 and send it to exclusive-OR gate OR. Then, exclusive-OR gate OR will compare V02 and V04 to calculate voltage signal V05 and send the signal to AND gate AND. AND gate AND will compare V05 with the reference voltage V06 generated by charger J1 to calculate voltage signal VDQ and send the signal to the coil control terminal of electromagnetic contactor MC2.

[0016] When V06 is at a high level, that is, the charger is charging, and when V05 is at a high level, that is, there is an abnormal charging in the first battery pack B1 or the second battery pack B2. At this time, the coil control terminal of electromagnetic contactor MC2 will activate the knife switch of electromagnetic contactor MC2 to cut off the entire charging circuit.

[0017] When V06 is at a low level, that is, the charger is not charging, at this time, VDQ always outputs a low level and does not output an abnormal signal.

[0018] When V06 is at a high level, that is, the charger is charging, and when V05 is at a low level, that is, both the first battery pack B1 and the second battery pack B2 are in a normal charging state. At this time, VDQ outputs a low level and does not output an abnormal signal.

[0019] The present utility model has the following beneficial effects: high safety and high stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Attached Figure 1 is the schematic diagram of the present utility model.

[0021] Attached Figure 2This is the schematic diagram of the comparison circuit of the present utility model.

[0022] Load 1, comparison circuit 2. Specific implementation manner

[0023] Through embodiments and in combination with the drawings, the technical solution of the present utility model will be further specifically described.

[0024] Embodiment: According to the attached Figure 1 and the attached Figure 2 The present utility model will be further described. A circuit protection device based on non-stop charging of AGV in this example includes a control circuit board SAC, a load 1, a first battery pack B1, a second battery pack B2, and a charger J1. The output ends of the charger J1 are respectively electrically connected to the input ends of the first battery pack B1 and the second battery pack B2. The output ends of the first battery pack B1 and the second battery pack B2 are respectively electrically connected to the input end of the control circuit board SAC. The output end of the control circuit board SAC is electrically connected to the input end of the load 1. A protection circuit for protecting the circuit when a fault occurs in the line is provided on the output end of the charger J1.

[0025] The protection circuit described above includes current sensors CT1, CT2, electromagnetic contactors MC1, MC2, diodes D1, D2, D3, D4, and comparison circuit 2. The 1-pin of charger J1 is the N-pole contact. The 2-pin of charger J1 is electrically connected to one end of electromagnetic contactor MC2. The other end of electromagnetic contactor MC2 is electrically connected to one end of current sensor CT1 and one end of current sensor CT2 respectively. The other end of current sensor CT1 is the P1-pole contact. The other end of current sensor CT2 is the P2-pole contact. The coil control end of electromagnetic contactor MC2 is electrically connected to the signal output end of comparison circuit 2. The signal output ends of current sensors CT1 and CT2 are respectively electrically connected to the signal input ends of comparison circuit 2. The N-pole contact is electrically connected to the negative poles of the first battery pack B1, the second battery pack B2, the control circuit board SAC, and the negative pole of load 1 respectively. The P1-pole contact is electrically connected to the positive pole of diode D1. The P2-pole contact is electrically connected to the positive pole of diode D2. The negative pole of diode D1 is electrically connected to the positive pole of diode D3 and the positive pole of the first battery pack B1 respectively. The negative pole of diode D2 is electrically connected to the positive pole of diode D4 and the positive pole of the second battery pack B2 respectively. The negative poles of diode D3 and diode D4 are electrically connected to the positive pole of control circuit board SAC respectively. The positive pole of control circuit board SAC is electrically connected to one end of electromagnetic contactor MC1. The other end of electromagnetic contactor MC1 is electrically connected to the positive pole of load 1. The coil control end of electromagnetic contactor MC1 is electrically connected to the signal output end of control circuit board SAC.

[0026] The described comparison circuit 2 includes an operational amplifier chip CP1, an operational amplifier chip CP2, an exclusive-OR gate OR, an AND gate AND, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor Ri1, a resistor Ri2, a resistor Rref1, a resistor Rref2, a capacitor C1, a capacitor C2, and a reference circuit. One end of the 1-pin of the operational amplifier chip CP1 is electrically connected to one end of the resistor Ri1 and one end of the resistor Rref1. The other end of the resistor Ri1 is electrically connected to the signal output end of the current sensor CT1. The other end of the resistor Rref1 is electrically connected to the 5-pin of the operational amplifier chip CP1 and one end of the resistor R1. The other end of the resistor R1 is connected to VCC. The other end of the resistor R1 is electrically connected to the 4-pin of the operational amplifier chip CP1 and one end of the resistor R2. The other end of the resistor R2 is electrically connected to one end of the capacitor C1. The other end of the capacitor C1 is electrically connected to the 2-pin and the 3-pin of the operational amplifier chip CP1. The 3-pin of the operational amplifier chip CP1 is grounded. The other end of the resistor R2 is electrically connected to the 1-pin of the exclusive-OR gate OR. One end of the 1-pin of the operational amplifier chip CP2 is electrically connected to one end of the resistor Ri2 and one end of the resistor Rref2. The other end of the resistor Ri2 is electrically connected to the signal output end of the current sensor CT2. The other end of the resistor Rref2 is electrically connected to the 5-pin of the operational amplifier chip CP2 and one end of the resistor R3. The other end of the resistor R3 is connected to VCC. The other end of the resistor R3 is electrically connected to the 4-pin of the operational amplifier chip CP2 and one end of the resistor R4. The other end of the resistor R4 is electrically connected to one end of the capacitor C2. The other end of the capacitor C2 is electrically connected to the 2-pin and the 3-pin of the operational amplifier chip CP2. The 3-pin of the operational amplifier chip CP2 is grounded. The other end of the resistor R4 is electrically connected to the 2-pin of the exclusive-OR gate OR. The 3-pin of the exclusive-OR gate OR is electrically connected to the 1-pin of the AND gate AND. The 3-pin of the AND gate AND is electrically connected to the coil control end of the electromagnetic contactor MC2. The output end of the reference circuit is electrically connected to the 2-pin of the AND gate AND.

[0027] The above are only specific embodiments of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present invention are covered by the patent scope of the present invention.

Claims

1. A circuit protection device based on AGV non-stop charging, comprising a control circuit board SAC, a load (1), a No. 1 battery pack B1, a No. 2 battery pack B2 and a charger J1, wherein: The output end of the charger J1 is electrically connected to the input end of the No. 1 battery pack B1 and the input end of the No. 2 battery pack B2 respectively, the output end of the No. 1 battery pack B1 and the output end of the No. 2 battery pack B2 are electrically connected to the input end of the control circuit board SAC respectively, the output end of the control circuit board SAC is electrically connected to the input end of the load (1), and a protection circuit for protecting the line when a line fault occurs is provided at the output end of the charger J1.

2. A circuit protection device based on AGV non-stop charging according to claim 1, characterized in that: The protection circuit comprises a current sensor CT1, a current sensor CT2, an electromagnetic contactor MC1, an electromagnetic contactor MC2, a diode D1, a diode D2, a diode D3, a diode D4 and a comparison circuit (2), wherein the 1 pin of the charger J1 is an N-pole contact, the 2 pin of the charger J1 is electrically connected to one end of the electromagnetic contactor MC2, the other end of the electromagnetic contactor MC2 is electrically connected to one end of the current sensor CT1 and one end of the current sensor CT2 respectively, the other end of the current sensor CT1 is a P1-pole contact, the other end of the current sensor CT2 is a P2-pole contact, the coil control end of the electromagnetic contactor MC2 is electrically connected to the signal output end of the comparison circuit (2), the signal output end of the current sensor CT1 and the signal output end of the current sensor CT2 are electrically connected to the signal input end of the comparison circuit (2) respectively, and the N-pole The contacts are electrically connected to the negative electrode of the No. 1 battery pack B1, the negative electrode of the No. 2 battery pack B2, the negative electrode of the control circuit board SAC and the negative electrode of the load (1), respectively; the P1 pole contact is electrically connected to the positive electrode of the diode D1, the P2 pole contact is electrically connected to the positive electrode of the diode D2, the negative electrode of the diode D1 is electrically connected to the positive electrode of the diode D3 and the positive electrode of the No. 1 battery pack B1, the negative electrode of the diode D2 is electrically connected to the positive electrode of the diode D4 and the positive electrode of the No. 1 battery pack B2, the negative electrode of the diode D3 and the negative electrode of the diode D4 are electrically connected to the positive electrode of the control circuit board SAC, the positive electrode of the control circuit board SAC is electrically connected to one end of the electromagnetic contactor MC1, the other end of the electromagnetic contactor MC1 is electrically connected to the positive electrode of the load (1), and the coil control end of the electromagnetic contactor MC1 is electrically connected to the signal output end of the control circuit board SAC.

3. The circuit protection device based on AGV non-stop charging according to claim 2 is characterized in that: The comparison circuit (2) comprises an operational amplifier chip CP1, an operational amplifier chip CP2, an XOR gate OR, an AND gate AND, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor Ri1, a resistor Ri2, a resistor Rref1, a resistor Rref2, a capacitor C1, a capacitor C2 and a reference circuit, wherein a pin 1 of the operational amplifier chip CP1 is electrically connected to one end of the resistor Ri1 and one end of the resistor Rref1 respectively, the other end of the resistor Ri1 is electrically connected to the signal output end of the current sensor CT1, and the resistor Rref The other end of 1 is electrically connected to the 5th pin of the operational amplifier chip CP1 and one end of the resistor R1, the other end of the resistor R1 is connected to VCC, the other end of the resistor R1 is electrically connected to the 4th pin of the operational amplifier chip CP1 and one end of the resistor R2, the other end of the resistor R2 is electrically connected to one end of the capacitor C1, the other end of the capacitor C1 is electrically connected to the 2nd pin of the operational amplifier chip CP1 and the 3rd pin of the operational amplifier chip CP1, the 3rd pin of the operational amplifier chip CP1 is grounded, the other end of the resistor R2 is electrically connected to the XOR gate OR 1 pin of the operational amplifier chip CP2 is electrically connected to one end of the resistor Ri2 and one end of the resistor Rref2 respectively, the other end of the resistor Ri2 is electrically connected to the signal output end of the current sensor CT2, the other end of the resistor Rref2 is electrically connected to the 5 pin of the operational amplifier chip CP2 and one end of the resistor R3 respectively, the other end of the resistor R3 is connected to VCC, the other end of the resistor R3 is electrically connected to the 4 pin of the operational amplifier chip CP2 and one end of the resistor R4 respectively, the The other end is electrically connected to one end of the capacitor C2, the other end of the capacitor C2 is electrically connected to pin 2 of the operational amplifier chip CP2 and pin 3 of the operational amplifier chip CP2 respectively, pin 3 of the operational amplifier chip CP2 is grounded, the other end of the resistor R4 is electrically connected to pin 2 of the XOR gate OR, pin 3 of the XOR gate OR is electrically connected to pin 1 of the AND gate AND, pin 3 of the AND gate AND is electrically connected to the coil control end of the electromagnetic contactor MC2, and the output end of the reference circuit is electrically connected to pin 2 of the AND gate AND.

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