Starting circuit applied to heavy-load AGV

Abstract

The utility model discloses a starting circuit applied to a heavy-load AGV (Automatic Guided Vehicle), belongs to the technical field of heavy-load equipment, and solves the problems in the prior art that higher starting current is easily caused at the starting moment of a power battery, so that safety accidents are caused, and the power battery is in a standby state for a long time, so that loss is generated, and the service life of the battery is influenced. The device mainly comprises a battery management system BMS and a low-voltage battery G, the low-voltage battery G is respectively connected with a low-voltage control circuit and a high-voltage control circuit, the high-voltage control circuit is connected with the battery management system BMS, the battery management system BMS is connected with a high-voltage battery G3, and the high-voltage battery G3 is respectively connected with the low-voltage battery G and the low-voltage control circuit by being connected with a DC-DC converter. According to the utility model, high voltage and low voltage are separately controlled, low voltage is firstly applied, and then high voltage output is controlled through the low voltage, so that loss caused by long-term standby state of the high-voltage battery G3 is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of heavy-load equipment, in particular to a starting circuit applied to a heavy-load AGV. Background Art

[0002] With the development and progress of industrial automation, heavy-duty AGV has gradually become one of the main members of the automation industry. In order to improve the work rhythm, achieve higher work efficiency, and transport large tonnage materials, heavy-duty AGV usually uses high-voltage DC lithium batteries as power batteries. The voltage of this power battery is generally between 500V and 1000V. In order to eliminate the safety accidents caused by the high starting current generated at the moment of power battery starting, it is necessary to design a starting circuit on the AGV with a lead-acid low-voltage battery as the starting power supply.

[0003] For example, a heavy-duty equipment starting circuit disclosed in the application with announcement number CN219394720U, the main circuit is connected in series with the first power switch QF1 and a normally open contact of the contactor KM, the first current transformer TA1, the second current transformer TA2, the thermal relay FR, the time relay KT and the control circuit. In the motor starting stage of the heavy-duty equipment, the two energized delayed disconnection contacts of the time relay KT short-circuit the secondary side of the corresponding first current transformer TA1 and the second current transformer TA2, effectively avoiding malfunction caused by excessive starting current passing through the main contact of the thermal relay FR. This starting circuit usually uses a high-voltage DC lithium battery as a power battery, but its power output needs to be in a standby state for a long time, which causes loss, affects the battery life, and has poor adaptability. At present, there is a lack of a control circuit that can realize the starting of the heavy-duty AGV from low voltage to high voltage by adding a low-voltage starting battery, avoid the power output needs to be in a standby state for a long time, and increase the scope of application of the heavy-duty high-voltage battery G3. Summary of the invention

[0004] The purpose of the utility model is to provide a starting circuit for heavy-load AGVs to solve the problem in the prior art that the power battery is easily caused by a high starting current at the moment of starting, which in turn causes safety accidents, and the power battery is in a standby state for a long time, causing loss and affecting the battery life.

[0005] The utility model is realized by the following technical solutions:

[0006] A starting circuit for a heavy-loaded AGV comprises a battery management system BMS and a low-voltage battery G, wherein the low-voltage battery G is electrically connected to a low-voltage control circuit and a high-voltage control circuit respectively, the high-voltage control circuit is electrically connected to the battery management system BMS, the battery management system BMS is electrically connected to a high-voltage battery G3, the high-voltage battery G3 is electrically connected to a DC-DC converter, the DC-DC converter is electrically connected to the low-voltage battery G and the low-voltage control circuit respectively, and the low-voltage control circuit is electrically connected to a low-voltage load of the whole vehicle; the low-voltage control circuit comprises a key switch SA1 and a low-voltage starting switch SB1, the high-voltage battery G3 is electrically connected to a junction box JB7 and a junction box JB8 respectively through a high-voltage converter DC2, the low-voltage battery G and the low-voltage load of the whole vehicle are connected in series between the junction boxes JB7 and JB8, the junction box JB7 and the low-voltage load of the whole vehicle are electrically connected to the junction box JB2, and the junction box JB8 is electrically connected to the low-voltage load of the whole vehicle. A junction box JB1 is electrically connected between the junction box JB8 and the low-voltage load of the whole vehicle, the junction box JB8 is electrically connected to the key switch SA1, the key switch SA1 is electrically connected to the low-voltage starting switch SB1, the low-voltage starting switch SB1 is electrically connected to the intermediate relay KA0, the intermediate relay KA2 is connected in parallel at both ends of the intermediate relay KA0, the intermediate relay KA0 and the intermediate relay KA2 are electrically connected to the junction box JB2, the normally open contact KA01 of the intermediate relay KA0 is connected in parallel at both ends of the starting switch SB1, one end of the normally open contact KA21 of the intermediate relay KA2 is electrically connected to the junction box JB8, the other end of the normally open contact KA21 is electrically connected to the contactor KM1, the contactor KM1 is electrically connected to the junction box JB8, and the normally open contact KM11 of the contactor KM1 is connected in series between the junction box JB8 and the junction box JB1.

[0007] Furthermore, the high-voltage control circuit includes a high-voltage starting switch SB2 and a high-voltage stop switch SB3, a battery management system BMS is connected in series between the junction box JB1 and the junction box JB2, the junction box JB1 is electrically connected to the high-voltage starting switch SB2 and the high-voltage stop switch SB3, respectively, the high-voltage starting switch SB2 is electrically connected to the contactor KM2, the contactor KM2 is electrically connected to the junction box JB2, the normally open contact KM21 of the contactor KM2 is connected in parallel on both sides of the high-voltage starting switch SB2, the normally open contact KM22 of the contactor KM2 is connected in series between the junction box JB1 and the battery management system BMS, the high-voltage stop switch SB3 is electrically connected to the contactor KM3, and the contactor KM3 is electrically connected to the junction box JB2; the normally closed contact KM31 of the contactor KM3 is connected in series between the high-voltage starting switch SB2 and the contactor KM2.

[0008] Furthermore, the low-voltage battery G includes a low-voltage battery G1 and a low-voltage battery G2; the low-voltage battery G1 and the low-voltage battery G2 are connected in series.

[0009] Furthermore, the low-voltage battery G adopts a lead-acid battery. Compared with a lithium battery, the lead-acid battery has a more stable electromotive force during discharge, and has the advantages of stable operating voltage, wide operating temperature and current range, good storage performance, convenient disassembly and assembly, and low cost. This significantly reduces the costs of AGV design, manufacturing, maintenance, storage and repair, and significantly improves the working performance.

[0010] Furthermore, the low-voltage control circuit includes a circuit breaker QF1, which is respectively arranged between the junction box JB7 and the junction box JB2 and between the junction box JB8 and the junction box JB1.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] The utility model adopts the separate control of high voltage and low voltage, firstly supplies low voltage electricity, and then controls the high voltage electricity output through low voltage electricity, so as to avoid the high voltage battery G3 being in standby state for a long time and causing loss, which affects the service life of the high voltage battery G3; it can also avoid the large starting current generated by directly supplying high voltage, which causes irreversible damage to the high voltage electrical parts of the AGV. The optional range of the voltage value of the high voltage battery G3 becomes larger, and this circuit can meet the use conditions of various heavy-load AGVs. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0014] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the drawings of the present invention. Based on the embodiments in this application, other similar embodiments obtained by ordinary technicians in this field without making creative work should all fall within the scope of protection of this application. In addition, the directional words mentioned in the following embodiments, such as "up", "down", "left", "right", etc., are only referenced to the directions of the drawings. Therefore, the directional words used are used to illustrate rather than limit the creation of the present invention.

[0015] The utility model is further described below in conjunction with the accompanying drawings.

[0016] Embodiment 1: A starting circuit for a heavy-load AGV, such as Figure 1As shown, it includes a battery management system BMS and a low-voltage battery G, the low-voltage battery G is electrically connected to a low-voltage control circuit and a high-voltage control circuit respectively, the high-voltage control circuit is electrically connected to the battery management system BMS, the high-voltage control circuit is used to start and stop the battery management system BMS, the battery management system BMS is electrically connected to a high-voltage battery G3, the high-voltage battery G3 is electrically connected to a DC-DC converter, the DC-DC converter is electrically connected to the low-voltage battery G and the low-voltage control circuit respectively, the low-voltage control circuit is electrically connected to a low-voltage load of the whole vehicle, the low-voltage control circuit includes a key switch SA1 and a low-voltage starting switch SB1, the high-voltage battery G3 is electrically connected to a junction box JB7 and a junction box JB8 respectively through a high-voltage converter DC2, the low-voltage battery G and the low-voltage load of the whole vehicle are connected in series between the junction box JB7 and the junction box JB8, and the junction box JB2 is electrically connected between the junction box JB7 and the low-voltage load of the whole vehicle A junction box JB1 is electrically connected between the junction box JB8 and the low-voltage load of the whole vehicle, the junction box JB8 is electrically connected to a key switch SA1, the key switch SA1 is electrically connected to a low-voltage starting switch SB1, the low-voltage starting switch SB1 is electrically connected to an intermediate relay KA0, and intermediate relay KA2 is connected in parallel at both ends of the intermediate relay KA0, the intermediate relay KA0 and the intermediate relay KA2 are electrically connected to the junction box JB2, the normally open contact KA01 of the intermediate relay KA0 is connected in parallel at both ends of the starting switch SB1, one end of the normally open contact KA21 of the intermediate relay KA2 is electrically connected to the junction box JB8, the other end of the normally open contact KA21 is electrically connected to the contactor KM1, the contactor KM1 is electrically connected to the junction box JB8, and the normally open contact KM11 of the contactor KM1 is connected in series between the junction box JB8 and the junction box JB1. The power distribution is achieved through the positive distribution box and the negative distribution box, replacing the previous copper busbar distribution, avoiding the exposure of wires and copper busbars and causing unnecessary safety hazards.

[0017] Embodiment 2, a starting circuit for heavy-duty AGV, the high-voltage control circuit includes a high-voltage starting switch SB2 and a high-voltage stop switch SB3, a battery management system BMS is connected in series between the junction box JB1 and the junction box JB2, the junction box JB1 is electrically connected to the high-voltage starting switch SB2 and the high-voltage stop switch SB3, the high-voltage starting switch SB2 is electrically connected to the contactor KM2, the contactor KM2 is electrically connected to the junction box JB2, the normally open contact KM21 of the contactor KM2 is connected in parallel on both sides of the high-voltage starting switch SB2, the normally open contact KM22 of the contactor KM2 is connected in series between the junction box JB1 and the battery management system BMS, the high-voltage stop switch SB3 is electrically connected to the contactor KM3, the contactor KM3 is electrically connected to the junction box JB2; the normally closed contact KM31 of the contactor KM3 is connected in series between the high-voltage starting switch SB2 and the contactor KM2. The rest is the same as embodiment 1.

[0018] The low-voltage battery G includes a low-voltage battery G1 and a low-voltage battery G2; the low-voltage battery G1 and the low-voltage battery G2 are connected in series. The low-voltage battery G adopts a lead-acid battery. Compared with a lithium battery, the lead-acid battery has a more stable electromotive force during discharge, and has the advantages of stable working voltage, wide operating temperature and current range, good storage performance, convenient disassembly and assembly, and low cost; the low-voltage control circuit includes a circuit breaker QF1, which is respectively arranged between the junction box JB7 and the junction box JB2 and between the junction box JB8 and the junction box JB1; the circuit breaker QF1 quickly cuts off the faulty part from the circuit to ensure the normal operation of the non-faulty part of the circuit.

[0019] AGV startup process: The lead-acid battery G1 and the lead-acid battery G2 are connected in series to obtain a DC24V voltage that meets the requirements of the AGV low-voltage load. The low-voltage circuit breaker QF1 is closed, and the key switch SA1SY1 is turned to the closed position. The power supply of the start circuit is closed, and the low-voltage start button SB1 is pressed. The coil of the intermediate relay KA0 is energized, and the normally open contact KA01 of the intermediate relay KA0 is closed to achieve self-locking. The start circuit is energized, the coil of the intermediate relay KA2 is energized, and the normally open contact KA21 of the intermediate relay KA2 is closed. The coil of the contactor KM1 is energized, and the normally open contact KM11 of the contactor KM1 is closed. The low-voltage battery supplies power to the low-voltage load of the vehicle.

[0020] Press the high-voltage start button S to energize the coil of contactor KM2, close the normally open contact KM21 of contactor KM2, and realize the self-locking of the circuit. At the same time, the battery management system BMS is energized, and the battery management system BMS controls the high-voltage battery G3 to start discharging. The DC-DC converter DC2 inputs the DC520V voltage and outputs the DC27V voltage to power the AGV low-voltage load, and charges the lead-acid battery G1 and the lead-acid battery G2 at the same time, ensuring the normal start of the AGV. At this point, the AGV is started.

[0021] When the high-voltage stop button SB3 is pressed, the coil of contactor KM3 is energized, the normally closed contact KM31 of contactor KM3 is disconnected, the coil of contactor KM2 is de-energized, the normally open contact KM21 of contactor KM2 is disconnected, the battery management system BMS is powered off, the high-voltage battery G3 stops discharging, the DC-DC converter DC2 stops outputting, and the AGV low-voltage load is powered by the lead-acid battery G1 and the lead-acid battery G2.

[0022] Turn the key switch SA1 to the disconnect position, the coils of the intermediate relay KA0 and the intermediate relay KA2 lose power, the normally open contacts of the intermediate relay KA0 and the low-voltage power supply relay KA2 are disconnected, the coil of the low-voltage power supply contactor KM1 loses power, the normally open contacts of the contactor KM1 are disconnected, the low-voltage control circuit is disconnected, and the low-voltage load of the AGV loses power. At this point, the AGV is powered off. In an emergency, the key switch SA1 can also be turned off to control the high and low voltage power supplies of the AGV to be powered off at the same time.

[0023] The present invention has been described in detail above. The above description is only a preferred embodiment of the present invention and should not limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made within the scope of this application should still fall within the scope of the present invention.

Claims

1. A starting circuit for a heavy-load AGV, comprising a battery management system BMS and a low-voltage battery G, characterized in that: The low-voltage battery G is electrically connected to a low-voltage control circuit and a high-voltage control circuit respectively, the high-voltage control circuit is electrically connected to a battery management system BMS, the battery management system BMS is electrically connected to a high-voltage battery G3, the high-voltage battery G3 is electrically connected to a DC-DC converter, the DC-DC converter is electrically connected to the low-voltage battery G and the low-voltage control circuit respectively, the low-voltage control circuit is electrically connected to a low-voltage load of the whole vehicle; the low-voltage control circuit includes a key switch SA1 and a low-voltage starting switch SB1, the high-voltage battery G3 is electrically connected to a junction box JB7 and a junction box JB8 respectively through a high-voltage converter DC2, the low-voltage battery G and the low-voltage load of the whole vehicle are connected in series between the junction box JB7 and the junction box JB8, the junction box JB7 and the low-voltage load of the whole vehicle are electrically connected to the junction box JB2, the junction box JB8 and the low-voltage load of the whole vehicle are electrically connected It is connected to a junction box JB1, the junction box JB8 is electrically connected to a key switch SA1, the key switch SA1 is electrically connected to a low-voltage starting switch SB1, the low-voltage starting switch SB1 is electrically connected to an intermediate relay KA0, both ends of the intermediate relay KA0 are connected in parallel with an intermediate relay KA2, the intermediate relay KA0 and the intermediate relay KA2 are electrically connected to the junction box JB2, the normally open contact KA01 of the intermediate relay KA0 is connected in parallel to both ends of the starting switch SB1, one end of the normally open contact KA21 of the intermediate relay KA2 is electrically connected to the junction box JB8, the other end of the normally open contact KA21 is electrically connected to the contactor KM1, the contactor KM1 is electrically connected to the junction box JB8, and the normally open contact KM11 of the contactor KM1 is connected in series between the junction box JB8 and the junction box JB1.

2. The starting circuit for heavy-load AGV according to claim 1 is characterized in that: The high-voltage control circuit includes a high-voltage starting switch SB2 and a high-voltage stop switch SB3. A battery management system BMS is connected in series between the junction box JB1 and the junction box JB2. The junction box JB1 is electrically connected to the high-voltage starting switch SB2 and the high-voltage stop switch SB3 respectively. The high-voltage starting switch SB2 is electrically connected to the contactor KM2, and the contactor KM2 is electrically connected to the junction box JB2. The normally open contact KM21 of the contactor KM2 is connected in parallel on both sides of the high-voltage starting switch SB2. The normally open contact KM22 of the contactor KM2 is connected in series between the junction box JB1 and the battery management system BMS. The high-voltage stop switch SB3 is electrically connected to the contactor KM3, and the contactor KM3 is electrically connected to the junction box JB2; the normally closed contact KM31 of the contactor KM3 is connected in series between the high-voltage starting switch SB2 and the contactor KM2.

3. The starting circuit for heavy-load AGV according to claim 1 is characterized in that: The low-voltage battery G comprises a low-voltage battery G1 and a low-voltage battery G2; the low-voltage battery G1 and the low-voltage battery G2 are connected in series.

4. The starting circuit for heavy-load AGV according to claim 1 is characterized in that: The low-voltage battery G is a lead-acid battery.

5. The starting circuit for heavy-load AGV according to claim 2 is characterized in that: The low voltage control circuit comprises a circuit breaker QF1, which is respectively arranged between the junction box JB7 and the junction box JB2 and between the junction box JB8 and the junction box JB1.

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