阅读说明：本技术 一种叉车用高集成度多功能高压配电箱 (High-integration-level multifunctional high-voltage distribution box for forklift ) 是由 郭志阳 周鸿波 陆建山 刘志洋 余凯 于 2021-08-17 设计创作，主要内容包括：本发明提出了一种叉车用高集成度多功能高压配电箱,包括锂电池接口,所述锂电池接口与整车接口之间通过母线连接,所述母线的前端设有锂电主接触器,所述母线上设有连接燃料电池接口的燃料电池支路和若干个用于连接功率器件的功率器件支路,所述功率器件支路的末端设有高压连接器,所述母线上设有用于检测电压电流的功率采集模块。设计了锂电池接口和燃料电池接口,在系统启动阶段,锂电池作为整个叉车系统的主要能量来源,燃料电池的启动电源由锂电池提供；随着燃料电池的输出功率逐渐增加,主要能量来源为燃料电池,燃料电池既可以提供整车运行的动力,也可以给锂电池充电,从而解决了双源混动系统匹配难题,系统集成度更高,灵活性更强。(The invention provides a high-integration-level multifunctional high-voltage distribution box for a forklift, which comprises a lithium battery interface, wherein the lithium battery interface is connected with a whole vehicle interface through a bus, a lithium battery main contactor is arranged at the front end of the bus, a fuel battery branch connected with the fuel battery interface and a plurality of power device branches used for connecting power devices are arranged on the bus, a high-voltage connector is arranged at the tail end of each power device branch, and a power acquisition module used for detecting voltage and current is arranged on the bus. A lithium battery interface and a fuel cell interface are designed, in the system starting stage, the lithium battery is used as a main energy source of the whole forklift system, and a starting power supply of the fuel cell is provided by the lithium battery; along with the gradual increase of the output power of the fuel cell, the main energy source is the fuel cell, and the fuel cell can provide the power for the running of the whole vehicle and can also charge the lithium battery, so that the problem of matching of a double-source hybrid system is solved, the system integration level is higher, and the flexibility is stronger.)

1. The utility model provides a multi-functional high voltage distribution box of high integration level for fork truck which characterized in that: including lithium battery interface, fuel cell interface, whole car interface, high-pressure connector and power acquisition module, be connected through the generating line between lithium battery interface and the whole car interface, the front end of generating line is equipped with lithium electricity main contactor, be equipped with the fuel cell branch road and the power device branch road that a plurality of that connect the fuel cell interface on the generating line is used for connecting the power device, the end of power device branch road is equipped with high-pressure connector, all be equipped with the fuse on fuel cell branch road and the power device branch road, be equipped with the power acquisition module that is used for measuring voltage electric current on the generating line.

2. The high-integration-level multifunctional high-voltage distribution box for the forklift as claimed in claim 1, wherein: the power device branch road includes air compressor machine branch road, step-down DC branch road, circulating pump branch road and heater branch road, the air compressor machine is propped up including air compressor machine output branch road and air compressor machine preliminary filling control branch road on the road, air compressor machine output branch road and air compressor machine preliminary filling control branch road are parallelly connected, air compressor machine output branch road and air compressor machine preliminary filling control are propped up and are all equipped with switch contactor on the road, the circulating pump is propped up and is equipped with switch contactor on the road, the heater is propped up and is equipped with switch contactor on the road.

3. The high-integration-level multifunctional high-voltage distribution box for the forklift as claimed in claim 2, wherein: the utility model discloses a heating device, including heater branch road, pile output branch road, be equipped with the pile output branch road on the heater branch road, the end of pile output branch road is equipped with the high voltage connector who is used for connecting the pile output, be equipped with the diode on heater branch road and pile output branch road, be equipped with switch contactor on the pile output branch road, adopt single-pole double-throw relay to be connected between the switch contactor on the heater branch road and the switch contactor on the pile output branch road.

4. The high-integration-level multifunctional high-voltage distribution box for the forklift as claimed in claim 1, wherein: the power acquisition module is connected with a forklift emergency stop switch and a forklift key switch, and is provided with a communication line and a power supply interface.

5. The high-integration-level multifunctional high-voltage distribution box for the forklift as claimed in claim 1, wherein: still include fork truck knob switch, fork truck knob switch is connected with the lithium cell interface, fork truck knob switch department is equipped with power holding circuit, power holding circuit is connected with the fuel cell interface, last diode and the switch contactor of being equipped with of power holding circuit, power holding circuit is connected with power acquisition module.

Technical Field

The invention relates to the technical field of high-voltage distribution box design, in particular to a high-integration-level multifunctional high-voltage distribution box for a forklift.

Background

The high-voltage distribution box is electrically connected with the high-voltage components through buses and wire harnesses, provides functions of charge and discharge control, high-voltage component electrifying control, circuit overload short-circuit protection, high-voltage sampling, low-voltage control and the like for a high-voltage system, and protects and monitors the operation of the high-voltage system.

A high voltage distribution box for a conventional fuel cell engine is shown in schematic form in fig. 1 and generally includes three parts, a fuse, a contactor, and a high voltage connector. The main functions mainly comprise overcurrent protection, overload protection, current distribution, power switch control, air compressor pre-charging control and the like. The power devices that are typically controlled have a compressor, a step-down DC, a circulation pump, and a heater. The air compressor mainly provides continuous air for a cathode loop of the fuel cell; the reduced voltage DC is the main source of the low-voltage auxiliary power supply of the fuel cell engine; the circulating pump mainly provides main power for the anode circulation of the fuel cell; the heater mainly enables the fuel cell engine to enter a rated working state more quickly and solves the problem of low-temperature cold start.

The existing technical scheme has single function, cannot be matched with a dual-source system, cannot fully utilize the function of a heater and cannot monitor the voltage and current functions of each loop. With the new generation of fuel cell engines, this principle has not been satisfactory for everyday use, especially on fuel cell forklifts, and has become more dwarfed after comparison.

Because most fuel cell forklifts in the current market are all manufactured by pure electric forklifts or original lead-acid battery forklifts, the whole vehicle and a battery system have no communication function, and a power supply system cannot timely and effectively know the running state and the power requirement of the whole vehicle; the power supply system is not communicated with the whole vehicle, and the power supply system cannot monitor the driving intention of a driver of the whole vehicle.

Disclosure of Invention

The invention aims to provide a high-integration-level multifunctional high-voltage distribution box for a forklift, which overcomes the defects in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme:

the application discloses multi-functional high voltage distribution box of high integration degree for fork truck, including lithium cell interface, fuel cell interface, whole car interface, high voltage connector and power acquisition module, be connected through the generating line between lithium cell interface and the whole car interface, the front end of generating line is equipped with lithium electricity main contactor, be equipped with the fuel cell branch road and the power device branch road that a plurality of that connect the fuel cell interface on the generating line is used for connecting power device, the end of power device branch road is equipped with high voltage connector, all be equipped with the fuse on fuel cell branch road and the power device branch road, be equipped with the power acquisition module who is used for measuring voltage electric current on the generating line.

As preferred, the power device branch road includes air compressor machine branch road, step-down DC branch road, circulating pump branch road and heater branch road, the air compressor machine is propped up including air compressor machine output branch road and air compressor machine preliminary filling control branch road on the road, air compressor machine output branch road and air compressor machine preliminary filling control branch road are parallelly connected, air compressor machine output branch road and air compressor machine preliminary filling control are propped up and are all equipped with switch contactor on the road, the circulating pump is propped up and is equipped with switch contactor on the road, the heater is propped up and is equipped with switch contactor on the road.

Preferably, a pile output branch is arranged on the heater branch, a high-voltage connector used for connecting the pile output is arranged at the tail end of the pile output branch, diodes are arranged on the heater branch and the pile output branch, a switch contactor is arranged on the pile output branch, and the switch contactor on the heater branch is connected with the switch contactor on the pile output branch through a single-pole double-throw relay.

Preferably, the power acquisition module is connected with a forklift emergency stop switch and a forklift key switch, and a communication line and a power supply interface are arranged on the power acquisition module.

Preferably, the system further comprises a forklift knob switch, the forklift knob switch is connected with the lithium battery interface, a power supply holding circuit is arranged at the forklift knob switch and connected with the fuel battery interface, a diode and a switch contactor are arranged on the power supply holding circuit, and the power supply holding circuit is connected with the power acquisition module.

The invention has the beneficial effects that:

1. a lithium battery interface and a fuel cell interface are designed, in the system starting stage, the lithium battery is used as a main energy source of the whole forklift system, and in the initial starting stage of the fuel cell, a starting power supply of the fuel cell is provided by the lithium battery; along with the gradual increase of the output power of the fuel cell, the main energy source of the forklift system is the fuel cell, and at the moment, the fuel cell can provide the power for the running of the whole forklift and can also charge the lithium battery. When the whole vehicle is loaded rapidly, the fuel cell and the lithium battery can be output externally at the same time, so that the matching problem of the dual-source hybrid system is solved, the system integration level is higher, and the flexibility is stronger;

2. the heater branch and the electric pile output branch are designed, and the dual functions of the heater are realized: the heater is used for accelerating the heating rate in the starting and heating process of the engine of the fuel cell, so that the engine of the fuel cell enters a rated working state as soon as possible; the fuel cell is used as a power resistor to achieve the effect of reducing the output voltage of the stack, and the service life of the stack is reduced due to the overhigh voltage of the fuel cell in the processes of starting and shutting down the fuel cell; meanwhile, the heater is used as a power resistor, so that the residual electric quantity in the galvanic pile can be quickly consumed, and the shutdown speed is accelerated;

3. the switch contactor on the heater branch and the switch contactor on the pile output branch are connected by adopting a single-pole double-throw relay, and diodes are arranged on the heater branch and the pile output branch for preventing reverse connection, so that the situation that the heater contactor and a voltage reduction resistor are closed simultaneously when control is wrong and a pile is damaged by reverse voltage is avoided;

4. the power acquisition module is added on the bus, the required power and the running state of the whole forklift can be fed back in real time by detecting the voltage and the current in real time, and the engine of the fuel cell can control the output power of the fuel cell in real time according to the state quantity, so that all running working conditions of the forklift are met;

5. the power acquisition module monitors the state of the emergency stop switch and the state of the key switch, when the emergency stop switch and the key switch are closed, the monitored voltage is consistent with the bus voltage, and if the emergency stop switch is disconnected, the voltage is instantly reduced to 0V. Through the mechanism, the battery control system can clearly know the driving intention of the driver and timely feed back the operation requirement of the driver;

6. the power supply holding circuit is designed, the controller of the fuel cell can judge the state of the knob switch in real time according to the voltage U3 collected by the power module, if the voltage loss is detected, the control system of the fuel cell immediately executes the shutdown process, and the power supply holding relay is disconnected after the shutdown of the fuel cell is completed and the required power of the whole vehicle becomes zero, so that the safety performance and the service life of the battery system are improved.

The features and advantages of the present invention will be described in detail by embodiments in conjunction with the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of a high voltage distribution box used in a conventional fuel cell engine;

FIG. 2 is a schematic diagram of a high-integration multifunctional high-voltage distribution box for a forklift truck according to the present invention;

in the figure: the system comprises a lithium battery main contactor 1, a forklift knob switch 2, a power acquisition module 3, a forklift key switch 4, a forklift emergency stop switch 5, a single-pole double-throw relay 6, a communication line 7, a power interface 8 and a power holding circuit 9.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood, however, that the description herein of specific embodiments is only intended to illustrate the invention and not to limit the scope of the invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

Referring to fig. 2, the embodiment of the invention provides a high-integration-level multifunctional high-voltage distribution box for a forklift, which comprises a lithium battery interface, a fuel battery interface, a whole vehicle interface, a high-voltage connector and a power acquisition module 3, wherein the lithium battery interface is connected with the whole vehicle interface through a bus, a lithium battery main contactor 1 is arranged at the front end of the bus, a fuel battery branch connected with the fuel battery interface and a plurality of power device branches used for connecting power devices are arranged on the bus, the high-voltage connector is arranged at the tail end of each power device branch, fuses are arranged on the fuel battery branch and the power device branches, and the power acquisition module 3 used for detecting voltage and current is arranged on the bus. The power device branch road includes air compressor machine branch road, step-down DC branch road, circulating pump branch road and heater branch road, the air compressor machine is propped up including air compressor machine output branch road and air compressor machine preliminary filling control branch road on the road, air compressor machine output branch road and air compressor machine preliminary filling control branch road are parallelly connected, air compressor machine output branch road and air compressor machine preliminary filling control are propped up and are all equipped with switch contactor on the road, the circulating pump is propped up and is equipped with switch contactor on the road, the heater is propped up and is equipped with switch contactor on the road. The utility model discloses a heating device, including heater branch road, pile output branch road, be equipped with the pile output branch road on the heater branch road, the end of pile output branch road is equipped with the high voltage connector who is used for connecting the pile output, be equipped with the diode on heater branch road and pile output branch road, be equipped with switch contactor on the pile output branch road, adopt single-pole double-throw relay 6 to be connected between the switch contactor on the heater branch road and the switch contactor on the pile output branch road. The power acquisition module 3 is connected with a forklift emergency stop switch 5 and a forklift key switch 4, and a communication line 7 and a power supply interface 8 are arranged on the power acquisition module 3. Still include fork truck knob switch 2, fork truck knob switch 2 is connected with the lithium cell interface, fork truck knob switch 2 department is equipped with power holding circuit 9, power holding circuit 9 is connected with the fuel cell interface, be equipped with diode and switch contactor on the power holding circuit 9, power holding circuit 9 is connected with power acquisition module 3. The high-voltage interlocking function is added, all connectors are provided with interlocking wires, when one connector is disconnected, the system can immediately find abnormality, a high-voltage power supply is cut off, and the accidents of electric leakage and electric shock are avoided.

1. The newly added electricity-electricity hybrid scheme can realize the technical scheme of double sources and multiple sources. The system has higher integration level and stronger flexibility.

2. The dual function of the heater and the dual interlocking function are realized. The cost and the arrangement space of using the voltage reduction resistor and the heater respectively can be saved, the realization of the interlocking function can be used as the redundant design of the safety function, and the damage of the galvanic pile caused by software and artificial misoperation is avoided.

3. The method can be used for monitoring the power consumption of the whole forklift, counting the average power consumption and the instantaneous maximum power consumption of the forklift, and is greatly helpful for adjusting the output power of a fuel cell engine and counting the average power consumption of the forklift.

4. The power supply maintaining function of the main power supply is greatly helpful for low-temperature cold start delayed shutdown of the fuel cell. In a low-temperature environment, the shutdown time of the fuel cell is about 10 minutes, and the low-temperature purging function needs to be completed. The fuel cell controller can automatically turn off a power supply holding relay (time delay relay) according to the condition of low-temperature purging completion.

In the above scheme, the boost DC low current load can be designed to replace the function of the buck resistor;

the communication mode between the whole vehicle, the lithium battery BMS and the fuel cell is increased to monitor the power request of the whole vehicle and the operation intention of a driver in real time.

The working process of the invention is as follows:

starting up the process: the method comprises the steps that a forklift knob switch 2 is closed → a lithium battery BMS is electrified → a lithium battery main contactor 1 is closed (lithium battery output + and-electrification) → voltage reduction DC electrification → a fuel battery controller is electrified → the fuel battery controller judges whether a forklift emergency stop switch 5 and a forklift key switch 4 are started or not in a state selection mode → the fuel battery controller selects output power according to the power of a whole vehicle power acquisition module 3 and the state of a lithium battery.

Fuel cell shutdown procedure: the forklift key switch 4 is turned off → the whole vehicle is powered off and the power acquisition module 3 detects that the voltage at the forklift key switch 4 is lost → the fuel cell controller immediately executes the shutdown process.

A power-off process of the power supply system; powering off the key switch 4 of the forklift → completing the shutdown of the engine of the fuel cell → disconnecting the rotary switch 2 of the forklift → the power acquisition module monitors that the power supply holding circuit 9 is powered off → the switch contactor on the controller power supply holding circuit 9 of the fuel cell is disconnected → the built-in DC power off of the lithium battery → the completion of the power off.

Forklift emergency stop process: the whole vehicle presses a forklift emergency stop switch 5 → the forklift emergency stop → the power acquisition module 3 detects that the voltage at the forklift emergency stop switch 5 is lost → the fuel cell engine is suddenly stopped.

The power-off process of the forklift knob switch 2 is directly disconnected: disconnecting the forklift rotary switch 2 → losing voltage data at the power supply holding circuit 9 → executing shutdown process by the controller of the fuel cell → disconnecting the switch contactor on the power supply holding circuit 9 after shutdown is completed → powering off the whole vehicle.

The main power supply keeps and delays the power-off function:

firstly, from the safety point of view: if the power-off maintaining function is not available, the knob switch is directly disconnected, the lithium battery is disconnected at the moment, the whole vehicle stops immediately, and the battery engine stops suddenly. If power is suddenly lost when the vehicle runs on a road, great potential safety hazard exists; secondly, considering the service life of the battery system: the direct disconnection of the knob switch can cause the instant disconnection of the main contactor of the lithium battery, and the contactor can seriously influence the service life when the contactor is cut off under load; meanwhile, when the fuel cell operates normally, the main power supply and the auxiliary power supply are suddenly lost, so that the engine can be immediately and suddenly stopped, the heat in the galvanic pile can not be dissipated, the residual voltage of the galvanic pile can not be consumed, the output voltage of the galvanic pile can be kept at a very high voltage platform, and the service life of the galvanic pile can be seriously attenuated to be unusable for a long time. After the power supply holding function is added, the controller of the fuel cell can judge the state of the forklift knob switch 2 in real time according to the voltage of the power supply holding circuit 9 acquired by the power acquisition module 3, if the voltage loss is detected, the control system of the fuel cell immediately executes a shutdown process, and a switch contactor of the power supply holding circuit 9 is disconnected after the shutdown of the fuel cell is completed and the required power of the whole forklift becomes zero.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.