CN210912096U

CN210912096U - Fuel cell automobile multi-source controller

Info

Publication number: CN210912096U
Application number: CN201920518665.XU
Authority: CN
Inventors: 明巧红; 徐康聪; 李敏强
Original assignee: Shanghai Hanao New Energy Technology Co ltd
Current assignee: Shanghai Hanao New Energy Technology Co ltd
Priority date: 2019-04-17
Filing date: 2019-04-17
Publication date: 2020-07-03
Anticipated expiration: 2029-04-17

Abstract

The utility model discloses a fuel cell automobile multi-source controller, the multi-source controller function comprises a fuel cell engine controller and a whole automobile controller and a communication function with a whole automobile intelligent control system, the multi-source controller comprises a fuel cell stack, a stack operation monitoring device, a stack operation environment control device, a controller, an upper computer and interaction and control of a fuel cell system, a whole automobile and external input information, the multi-source controller and the control method solve the problem that the fuel cell engine controller and the whole automobile controller on the existing fuel cell automobile are designed and operated independently by two sets of software and hardware, are not beneficial to resource integration, cause resource waste, are difficult to reduce cost, and the fuel cell engine controller and the whole automobile controller on the existing fuel cell automobile are designed independently by the software and hardware respectively, are not beneficial to function safety, electromagnetic compatibility, safety redundancy and intelligent control on the integrated demand design of chips and systems, increasing the problem of system risk.

Description

Fuel cell automobile multi-source controller

Technical Field

The utility model belongs to fuel cell car field, concretely relates to fuel cell car multiple source controller.

Background

The fuel cell engine controller is the brain of the fuel cell engine and controls the safe and reliable operation of the fuel cell engine. The functions of a fuel cell engine controller mainly include gas management, electrical management, water management, thermal management, communication functions and fault diagnosis.

(1) Gas management, a hydrogen fuel cell, generates electricity mainly by the reaction of hydrogen and oxygen, and thus has an important role in the system. Firstly, the pressure of the reaction gas in the optimal operation state is selected according to the currently set power, and on the other hand, the reaction gas is continuously consumed, and the pressure fluctuation can be caused by the change of the flow rate. In order to ensure the normal operation of the fuel cell, a reasonable gas management system must be designed.

(2) The electrical management of the fuel cell mainly includes voltage detection of each unit cell, output current overcurrent protection, and the like. During the operation of the fuel cell, the stack monitor detects the cell voltage, the output total voltage, the output current, and the like in real time. If a single battery is damaged, the battery pack may not operate normally, or even explode. When the output current is overloaded, the battery pack also has faults and dangers, and the battery pack is stopped in time.

(3) Water management, effective water management is adopted, not only can the peak power of the battery be increased, but also the stability of the battery in the working process of the peak power can be increased. Maintaining proper humidity inside the cell and timely eliminating excessive water in the cathode side is one important means of ensuring stable operation and prolonging service life of proton exchange membrane fuel cell. The battery pack uses a tail gas recycle reactant gas humidification method. As the water and water generated in the FCE electrochemical reaction are transferred in the battery, the humidity of the tail gas discharged by the battery pack reaches or approaches 100 percent, so that the aim of humidifying the reaction gas can be fulfilled only by circulating the tail gas of the battery, mixing the tail gas with the newly-entered reaction gas which is not humidified, and then entering the battery pack. The tail gas circulation is carried out by adopting a fan, and the humidity of the reaction gas at the inlet of the battery pack is determined by the humidity of the circulating tail gas and the circulation ratio. The circulation ratio can be increased by increasing the rotating speed of the fan, so that the humidity of the reaction gas is improved.

(4) Thermal management refers to the control of the operating temperature of the battery. Approximately 50% of the heat must be removed when the FCE battery is maintained at 60-75 c. Appropriate cooling measures, such as air cooling or water cooling, are required to maintain the operating temperature of the stack. If the system adopts water cooling, the circulating cooling water enters the water tank after being deionized, the flow of the cooling water can be controlled by adjusting the rotating speed of the water pump, the cooling water passes through two paths, one path is the radiator, the other path is the bypass valve, and the final return water returns to the water tank again. By adjusting the opening of the bypass valve, the proportion of water flowing through the radiator can be controlled, so that the fuel cell stack can be rapidly heated. The cooling liquid adopts deionized water, and the conductivity requirement on the water is very strict.

(5) The FCE is a part of the vehicle, and needs to receive a work instruction of the vehicle controller and report a current working state and working parameters of the FCE to the vehicle controller, which are all implemented by the communication function of the FCE controller. Meanwhile, the FCE controller also needs to communicate with devices such as a computer and a diagnostic apparatus to implement functions such as debugging and fault diagnosis.

(6) The fault diagnosis function of the controller can quickly position the electric fault of the automobile; meanwhile, the safety of the vehicle when an electrical fault occurs in the driving process is ensured, and reasonable fault processing is the core of the functional safety of the vehicle. The perfect degree of FCE controller fault diagnosis determines the safety reliability and long-term maintainability of FCE and fuel cell vehicles.

The controller of the existing fuel cell taking hydrogen as fuel mainly comprises a power supply management module, an oxygen sensor control module, a fuel gas nozzle control module, a throttle valve control module, an analog input/output module, a switching value input/output module, a connector and a single chip microcomputer.

The existing fuel cell engine controller is in a high-speed development period, but the batch size is still small, and the quality level is not uniform. A fuel cell system is a multi-input multi-output complex electrochemical device, and a fuel cell is generally formed by connecting a plurality of single cells in series. In the process of operating the fuel cell, the fuel cell controller can detect and control the system state in real time, provide required raw materials and proper environment according to the actual operating state of the cell, and ensure the reliable and efficient operation of the fuel cell. The quality of the fuel cell engine controller, which is not well-leveled, is difficult to ensure that the fuel cell system operates efficiently and reliably.

Most of the existing fuel cell engine controllers experience less iteration, and the expansion requirements of functional safety, electromagnetic compatibility, safety redundancy and intelligent control on chips and systems are less considered.

The vehicle control unit on the existing fuel cell vehicle can provide abundant resources, but the actual resource usage amount is not large, which causes resource waste.

Two sets of software and hardware of a fuel cell engine controller and a vehicle control unit on the fuel cell vehicle are independently designed and operated, so that resource integration is not facilitated, resource waste is caused, and cost reduction is difficult.

The fuel cell engine controller and the whole vehicle controller software and hardware on the fuel cell vehicle are respectively and independently designed, so that the comprehensive requirements on the chip and the system for function safety, electromagnetic compatibility, safety redundancy and intelligent control are not satisfied, and the system risk is increased.

Disclosure of Invention

The utility model discloses the technical problem that will solve is: the multi-source controller and the control method solve the problems that most of the conventional fuel cell engine controllers have single hardware function, uneven quality and poor expandability, and are difficult to meet the software and hardware resource requirements of the conventional intelligent control of fuel cell engines and automobiles and the resource waste of the whole automobile controller on the conventional fuel cell automobile.

The utility model discloses a solve above-mentioned technical problem and adopt following technical scheme:

a fuel cell automobile multi-source controller comprises a core single chip microcomputer, a CAN interface filter circuit, a digital input expansion circuit, a digital output expansion circuit, an AD conversion circuit and a voltage-current conversion circuit; the CAN interface filter circuit is respectively connected with a CAN port of the core singlechip and a CAN network of the fuel cell system; the input end of the digital quantity input expansion circuit is connected with a digital quantity sensor of the fuel cell, and the output end of the digital quantity input expansion circuit is connected with the digital quantity input end of the core singlechip; the input end of the digital output expansion circuit is connected with the digital output end of the core singlechip, and the output end of the digital output expansion circuit is connected with the inductive load of the fuel cell; the input end of the AD conversion circuit is connected with an analog quantity sensor of the fuel cell, and the output end of the AD conversion circuit is connected with the analog quantity input end of the core single chip microcomputer; the input end of the voltage-current conversion circuit is connected with the analog quantity output end of the core single chip microcomputer, and the output end of the voltage-current conversion circuit is connected with the DC/DC and the frequency converter of the fuel cell; photoelectric isolation circuits are arranged among the digital input expansion circuit, the digital output expansion circuit, the analog output end, the CAN interface filter circuit and the core single chip microcomputer.

The digital quantity sensor comprises a gear signal sensor, a key signal sensor and a clutch switch signal sensor.

The analog quantity sensor comprises an accelerator pedal signal acquisition sensor.

The PWM signal acquisition circuit is connected with the PWM signal output circuit; the PWM signal acquisition circuit acquires a sine or pulse type rotating speed sensor signal; the PWM signal output circuit can control the fan, has a motor driving function, and can drive the throttle motor.

The communication of the CAN port adopts CANB2.0 standard, and the communication speed is 500 Kbps.

A control method of a fuel cell vehicle multi-source controller comprises starting mode control, energy distribution control, brake feedback control, fault diagnosis and fault tolerance control and driver intention interpretation control; in the starting process, selecting an operation mode according to the residual capacity of the power battery, and adopting a pure electric mode when the residual capacity of the power battery is greater than the maximum residual capacity; when the residual capacity of the power battery is greater than the minimum residual capacity and less than the maximum residual capacity, selecting a starting mode according to an instruction input by a driver; starting the fuel cell engine when the residual capacity of the power battery is less than the minimum residual capacity; after the automobile is started, energy distribution control, brake feedback control, fault diagnosis and fault tolerance control and driver intention interpretation control algorithms are executed according to each operation parameter of the automobile.

The vehicle start-stop state control logic is as follows:

step 1, turning a key to an ON gear, acquiring an ON gear signal input by the key by a controller, entering a 12V low-voltage power-ON mode, and controlling a power system component controller to be powered ON;

step 2, the key is screwed to the OFF gear within a certain time and then the ON gear is screwed back or the key is screwed to the Start gear, the controller inputs the key signal according to the collected key signal and judges whether the current component meets the starting state, if the current component meets the starting state, the electric vehicle enters the electric mode for starting, the controller sends out a BMS enabling signal, after the BMS finishes pre-charging, the current relay state and the system state are fed back to be ready, and the vehicle enters the pure electric mode;

step 3, after the electric mode is started successfully, the controller sends a DCL enabling instruction to supply power for a 12V system and charge a 12V storage battery, meanwhile, the controller sends enabling and torque commands to the motor controller according to the driving intention of a driver, and the vehicle runs in the pure electric mode;

step 4, directly screwing the key to a Start gear, directly entering a fuel cell starting mode after the pure electric mode is started successfully, sending a fuel cell enabling command by a controller, starting the fuel cell according to the command, entering the fuel cell mode after the pure electric mode is started successfully, sending a control command to the DCDC by the controller, sending set power of the fuel cell, and controlling output current by the DCDC to supply power for a driving system and charge a power battery;

step 5, after entering a fuel cell mode, normally driving the vehicle;

step 6, judging whether shutdown faults occur to all parts of the power system or whether a key is turned to an OFF gear, if so, enabling the vehicle to enter a shutdown process, firstly closing the fuel cell, sending a command for closing the fuel cell, waiting for the fuel cell to complete the shutdown process, sending a command for closing the fuel cell, then entering a pure electric mode for closing, sending a command for closing the power cell after entering an electric mode for closing, sending a command for discharging the motor at the same time, discharging the bus, and otherwise, returning to the step 5;

and 7, judging whether the bus voltage is lower than 60V or discharging overtime is 60s, if so, entering a low-voltage power-off mode, and controlling the low-voltage power-off of each node of the power system by the controller to finish the starting and stopping of the whole fuel cell system.

The torque control strategy comprises four parts of torque request, torque limitation, torque coordination and torque filtering, wherein the torque request comprises an accelerator pedal torque request, a creep torque request, a cruise torque request, an ESP interference torque request and an energy recovery torque request; the torque limitation limits the output of driving torque and recovery torque from the aspects of power limitation, vehicle speed limitation and torque limit value, and avoids battery overcurrent and motor overload;

the torque coordination determines the priority of each torque demand according to the working condition of the vehicle and the intention of a driver, and outputs the optimal torque under the current working condition;

the function of the torque filtering is to ensure that the torque is smoothly transited in time under various working conditions.

The energy distribution includes four modes: a pure electric mode, a fuel cell and power cell hybrid mode, an energy feedback mode, wherein,

the pure electric mode prohibits starting indoors, so that a driver can drive the vehicle out of the garage;

in the fuel cell mode, when the vehicle power is smaller than the preset power lower limit value, the maximum output power of the fuel cell completely meets the power requirement of the whole vehicle, and at the moment, the fuel cell is in a driving mode, the output power of the fuel cell supplies power to a driving system, and meanwhile, the energy can be supplemented for the power cell, so that the SOC of the power cell is ensured to be in a set range;

the fuel cell and the power cell are in a mixed mode, when the vehicle is in a mode larger than a preset power upper limit, the maximum output power of the fuel cell cannot meet the power requirement of the whole vehicle, at the moment, the fuel cell and the power cell are in a mixed driving mode, and the fuel cell and the power cell jointly supply power for a driving system to meet the driving requirement of the vehicle;

and in the regenerative braking mode, when the vehicle is in a deceleration or braking mode, the motor is driven to carry out energy feedback, the output power of the fuel cell is controlled according to the maximum allowable charging power of the power cell and the feedback power of the motor, when the feedback power is greater than the allowable charging power, the fuel cell outputs zero power, and simultaneously the feedback power is limited to the allowable charging power of the power cell, and when the feedback power is less than the allowable charging power, the fuel cell makes up the charging power required by the power cell currently, so that the overcharging of the power cell is avoided.

The fault diagnosis and fault-tolerant control comprises four stages, specifically as follows:

first-stage failure: the grade fault is an emergency shutdown fault, and when the fault occurs, the vehicle can automatically shut down the system;

secondary failure: the grade fault is a request shutdown fault, a pedal does not output a signal, a motor does not output torque, a vehicle cannot run, and an operator selects whether the fault is a specific fault type;

and (3) three-stage fault: the grade fault is a power reduction fault, when the grade fault occurs, the output of the motor torque is limited, so that the power output of a system is limited, and a driver can continue to run at a low speed and return to limp;

four-stage failure: when the grade fault occurs, no processing is carried out, and the operator only records the fault when the grade fault runs.

The high-voltage safety management control comprises collision safety, high-voltage interlocking, insulation detection, active discharge and passive discharge; wherein,

and (4) collision safety: after the vehicle is electrified at low voltage, the ACM needs to continuously detect the collision state and send the collision state out through a CAN message; if the vehicle is in collision, the ACM sends the collision state to the controller, and the controller forwards the collision state to the MCU, the FCE and the BMS; if the collision signal state is true, the controller guides the whole vehicle to be electrified under high voltage, the BMS/FCE immediately disconnects the high-voltage relay, and the MCU executes a 0-torque instruction; if collision occurs, the controller sets the collision fault to 1 before powering off, and stores the collision fault, if the vehicle is powered on again, the controller judges the collision fault state before guiding high-voltage power on, and if the collision fault state is 1, the high-voltage power on is forbidden; collision faults can be cleared by the diagnostic instrument, and after the faults are cleared, the vehicle can be powered on at normal high voltage;

high-pressure interlocking: the BMS detects the interlocking state of the high-voltage plug-in unit on the power battery pack, the fuel battery and the PCU and sends the interlocking state to the controller; if the controller receives the reported high-voltage interlocking state as 1, the controller enters fault processing according to the current speed and the high-voltage power-on state of the vehicle, and the specific strategy is as follows: if the whole vehicle is in static state and does not have high voltage, the whole vehicle cannot be electrified at high voltage, and meanwhile, the corresponding system fault lamp is lightened by the instrument; the whole vehicle is kept still and is subjected to high voltage, namely the running speed V of the vehicle is less than or equal to 5km/h, the whole vehicle is electrified under high voltage, and meanwhile, a corresponding system fault lamp is lightened by the instrument; the running speed V of the vehicle is more than 5km/h, the whole vehicle can run without limiting the speed, and meanwhile, the instrument lights a corresponding system fault lamp; after the fault disappears, the whole vehicle can be powered on only after being powered off;

insulation detection: the insulation detection task is completed by the BMS, the detection circuit is integrated in the BMS, and after high-voltage electrification is completed, the insulation resistance value detected by the BMS is the insulation resistance value of the direct-current bus of the whole vehicle and comprises a battery and all parallel high-voltage parts; the BMS needs to monitor the insulation resistance value, reports the low fault of the insulation resistance when the insulation resistance value is lower than a certain threshold value, and completes fault processing;

active discharging: after the high-voltage power failure of the vehicle, the voltage of a direct-current bus can be quickly reduced to be below 60V (DC) safe voltage within a set time through an active discharge circuit, wherein the active discharge circuit comprises an MCU (microprogrammed control unit) and a PTC (positive temperature coefficient) execution mechanism, the MCU and the PTC execute a discharge function according to a state machine, and after the high-voltage discharge state machine is detected, the MCU drives a motor winding or a resistance discharge loop to execute active discharge; the PTC controller is connected with the bus to execute active discharge by controlling the PTC heating resistor;

passive discharge: the fuel cell automobile should have a passive discharge function, which is executed by the MCU and must reduce the voltage of the dc bus to below 60v (dc) within a set time after the high voltage of the power cell is cut off;

hydrogen safety: the hydrogen concentration in the vehicle and in the trunk is detected through the HMS, the hydrogen concentration is guaranteed not to exceed the safety warning value, and a driver is reminded to correspondingly process the vehicle after the hydrogen concentration exceeds the warning concentration.

Compared with the prior art, the utility model discloses following beneficial effect has:

1. the fuel cell engine controller, the vehicle control unit and the intelligent control interaction hardware are integrated, so that hardware resources are fully utilized, and hardware cost is reduced.

2. A plurality of sets of hardware are integrated, so that the design of comprehensive requirements of functional safety, electromagnetic compatibility, safety redundancy and intelligent control on chips is facilitated, and the risk of system functional design is reduced.

3. The software control integration design of the multiple controllers is beneficial to the comprehensive coordination control and optimization of all functions.

Drawings

Fig. 1 is a diagram showing a power system of a hydrogen fuel cell vehicle.

Fig. 2 is a schematic diagram of the architecture principle of the fuel cell vehicle multi-source controller of the present invention.

Fig. 3 is a schematic diagram of a vms (vcu) system of the present invention.

Fig. 4 is the basic signal flow chart of the multi-source control system of the present invention.

Fig. 5 is the utility model discloses the vehicle opens stops state control flow chart.

Fig. 6 is a vehicle torque control flow chart of the present invention.

FIG. 7 vehicle energy distribution flow diagram.

FIG. 8 is a vehicle fault diagnosis and fault tolerance control flow diagram.

Detailed Description

The structure and working process of the present invention will be further explained with reference to the accompanying drawings.

Typically, the fuel cell auxiliary system is divided into four subsystems: a hydrogen supply subsystem; an air supply subsystem; a hydrothermal management subsystem; and a control subsystem. However, the subsystems are not completely independent, and some parts belong to different subsystems at the same time. Because of different types of fuel cells, the parts of the auxiliary system used in designing the whole fuel cell engine will be different, but in general, the four auxiliary subsystems can be divided.

1) The hydrogen supply subsystem mainly comprises a hydrogen storage system, a pressure regulating valve, a hydrogen circulating pump, a humidifier, a water separator, a pipeline and the like, and is used for processing hydrogen on the anode side of the fuel cell engine to a proper condition.

2) The air supply subsystem mainly comprises an air compressor/blower, a humidifier, a condenser, a water separator, a backpressure regulating valve, corresponding pipelines and other parts. To treat the air at the cathode side of the fuel cell to the appropriate conditions.

3) The water heat management subsystem mainly comprises a cooling water pump, a radiator, a fan, a humidifying water pump, a water tank, corresponding pipelines and the like, and meanwhile, partial functions of the humidifier, the condenser and the water separator also belong to the water heat management subsystem.

4) The control subsystem comprises a controller, a sensor, a driver and the like, wherein the controller consists of an electronic device which is formed by taking a set or a series of microcontrollers as a core and a corresponding control algorithm. The sensors are mainly pressure, temperature, voltage and current sensors, etc. The driver is mainly used for driving the air compressor/blower, the cooling water pump, the hydrogen circulating pump, the valve and other equipment.

The specific embodiment, as shown in fig. 1 to 3:

(1) after the fuel cell automobile multi-source controller is connected with a 12V (or 24V) power supply and an internal power supply enabling signal through a main control chip, an internal power supply output module provides voltage required inside the controller, then the controller starts to work, a controller input module collects working states and requirement information of all parts through analog input and switching value input, then the information is sent to the main control chip of the controller in a message form through an internal CAN communication protocol, after the main control chip receives the information, an internal control operation program is calculated and judged, and then a control instruction is issued.

(2) The control instruction is as follows, according to the air-fuel ratio signal fed back by the oxygen sensor, the main control chip gives a controller instruction to the gas nozzle to control the spraying amount of the gas; when the temperature of the working environment of the oxygen sensor is too high or too low, the main control chip controls the heating quantity of the oxygen sensor and always keeps the oxygen sensor in the optimal working state; when the oxygen concentration in the fuel cell is insufficient, a low-voltage signal is generated; after the main control chip receives, just can reach control command down, the work of control air pump, according to the concentration signal of hydrogen concentration sensor, main control chip can judge the size of the inside hydrogen concentration of fuel cell, then assigns control command, controls opening and shutting of inlet and outlet valve, guarantees that inside hydrogen of fuel cell and oxygen are in suitable concentration and pressure. According to the signal of the temperature sensor, the main control chip can obtain the working temperature of the fuel cell and then control the operation of the water pump, and the water flowing out of the water pump passes through the fuel cell and controls the temperature of the fuel cell through the heat exchange effect to ensure that the water is at the optimal working temperature. In addition, in order to control the fuel cell to output proper voltage, the fuel cell controller sends messages to the DC-DC through the CAN bus, the messages contain control instructions, and the DC-DC outputs proper voltage to the motor controller according to the instructions. In addition, a main control chip of the fuel cell automobile multi-source controller keeps communication with an external whole automobile through a CAN communication protocol.

(3) The fuel cell vehicle multi-source controller comprises the functions of a VMS (VCU), wherein the VMS (VCU) has a multi-channel digital signal input channel besides the functions of a vehicle controller in general meaning, and can acquire gear signals, key signals, clutch switching signals and the like; the device is provided with a plurality of analog quantity input channels, and can acquire analog and digital signals such as an accelerator pedal and gear signals; the device is provided with a plurality of PWM signal acquisition channels and can acquire rotating speed sensor signals in a sine or pulse form; the fan can be controlled by a multi-path PWM output mode; the motor driving function is provided, and the throttle motor can be driven.

The specific embodiment, as shown in fig. 4 to 8:

the vehicle start-stop state control logic is as follows:

step 1, a key is turned to an ON gear, VMS (VCU) collects an ON gear signal input by the key, and enters a 12V low-voltage power-ON mode to control power system components BMS, MCU, DCL, DCDC, FCE and other controllers to be powered ON, wherein VMS (VCU) is a whole vehicle controller, BMS is a battery management system, MCU is a motor controller, DCL is a high-voltage to low-voltage power converter, DC-DC is a direct-current power converter in a fuel cell power generation system, and FCE is a fuel cell engine controller;

step 2, turning the key to an OFF gear within a certain time, setting the embodiment as 2s, turning back the ON gear or turning the key to a Start gear, inputting the key signal by the controller according to the collected key signal, judging whether the current component meets the starting state, entering an electric mode for starting if the current component meets the starting state, sending a BMS enabling signal by the controller, feeding back the current relay state and the system state to be ready after the BMS finishes pre-charging, and entering a pure electric mode by the vehicle;

step 4, if the key is directly screwed to Start, after the pure electric mode is successfully started, directly entering a fuel cell starting mode, sending a fuel cell enabling command by a VMS (VCU), starting the fuel cell according to the command, after the pure electric mode is successfully started, entering the fuel cell mode, sending a control command to a DCDC by the VMS (VCU), sending set power of the fuel cell, and controlling output current of the DCDC to supply power for a driving system and charge a power battery;

step 5, if the fuel cell is started in a grading mode, in the pure electric mode, the fuel cell can enter a starting mode only by screwing a key to a Start gear; after entering the fuel cell mode, the vehicle normally runs;

step 6, after entering a fuel cell mode, the vehicle can normally run, whether a shutdown fault occurs to each part of a power system or a key is turned to an OFF gear is judged, if yes, the vehicle enters a shutdown process, the fuel cell is firstly closed, the fuel cell shutdown process needs to be waited for to complete the shutdown process after an instruction for closing the fuel cell is sent, after the instruction for completing the shutdown is sent, the vehicle enters a pure electric mode to be closed, after the vehicle enters an electric mode to be closed, the instruction for closing the power cell is sent, meanwhile, a motor discharge instruction is sent to discharge a bus, and if not, the vehicle returns to the step 5;

The torque control function is mainly used for considering according to comprehensive factors such as driver intention, actual working conditions and the like, converting the driver intention into a torque value, and finally sending a torque request to the MCU controller to drive the vehicle to work after a series of torque control, coordination, limitation and filtering. The torque control includes four parts of torque request, torque limitation, torque coordination and torque filtering.

The torque requests include an accelerator pedal torque request, a creep torque request, a cruise torque request, an ESP intervention torque request, and an energy recovery torque request.

The torque limitation mainly limits the output of driving torque and recovery torque from three aspects of power limitation, vehicle speed limitation and torque limit value (system maximum torque limit value and motor maximum torque), and avoids battery overcurrent and motor overload.

And determining the priority of each torque demand according to the working condition of the vehicle and the intention of a driver by the torque coordination, and outputting the optimal torque under the current working condition.

The torque filtering function is to ensure timely and smooth transition (except the interference condition of TCS and ABS) of the torque under various working conditions, and improve the smoothness and the driving performance of the vehicle.

The fuel cell vehicle has the following four modes according to energy distribution: a pure electric mode, a fuel cell and power cell mixed mode and an energy feedback mode.

These four energy distribution modes are illustrated:

(1) pure electric mode: the fuel cell automobile generally does not allow indoor starting from the safety point of view because the fuel is hydrogen, so the pure electric mode can be used for a driver to drive the automobile out of a garage.

(2) Fuel cell mode: when the vehicle is in a low-power mode, the maximum output power of the fuel cell completely meets the power requirement of the whole vehicle, and at the moment, the fuel cell is in a driving mode, the output power of the fuel cell supplies power for a driving system, and meanwhile, the energy can be supplemented for the power cell, so that the SOC of the power cell is ensured to be in a reasonable range.

(3) Fuel cell and power cell hybrid mode: when the vehicle is in a high-power mode, the maximum output power of the fuel cell cannot meet the power requirement of the whole vehicle, and at the moment, the fuel cell and the power cell are in a hybrid driving mode, and the fuel cell and the power cell jointly supply power to a driving system to meet the running requirement of the vehicle.

(4) Regenerative braking mode: when the vehicle is in a deceleration or braking mode, the driving motor can carry out energy feedback at the moment, the output power of the fuel cell can be controlled according to the maximum allowable charging power of the power cell and the feedback power of the motor, when the feedback power is larger than the allowable charging power, the fuel cell outputs zero power, the feedback power is limited to be the allowable charging power of the power cell, and when the feedback power is smaller than the allowable charging power, the fuel cell makes up the charging power required by the power cell at present, so that the overcharge of the power cell is avoided, and the service life and the safety of the power cell are influenced.

The main purposes of fault diagnosis and fault-tolerant control of fuel cells are: the safety, reliability and stability of vehicle running are ensured. Therefore, a hierarchical fault handling strategy is introduced into the fuel cell car to achieve the purpose. The fault diagnosis and fault-tolerant control comprises four stages, specifically as follows:

(1) first-stage failure: the grade fault is an emergency stop fault, and the vehicle automatically shuts down the system when the fault occurs.

(2) Secondary failure: the level failure is a request shutdown failure. The pedal does not output a signal, the motor does not output torque, and the vehicle cannot run. The driver or technician can select whether to shut down or not according to specific fault conditions.

(3) And (3) three-stage fault: the class fault is a reduced power fault. When the fault of the stage occurs, the output of the motor torque is limited, so that the power output of a limiting system is achieved, and a driver can continue to drive at a low speed and return limp. The processing mode greatly reduces the anchoring probability of the vehicle.

(4) Four-stage failure: when the grade fault occurs, no treatment is carried out, the fault possibly disappears in a short time, and the driver and engineering personnel only record the fault when the grade fault runs.

High-voltage safety management is a protective measure for preventing serious consequences caused by high-voltage runaway of an electric automobile, and mainly comprises the following steps: collision safety, high voltage interlock, insulation detection, active discharge, passive discharge, and hydrogen safety.

(1) And (4) collision safety: after the vehicle is electrified at low voltage, the ACM needs to continuously detect the collision state and send the collision state out through a CAN message; if the vehicle is in collision, the ACM sends the collision state to the VMS (VCU), and the VMS (VCU) forwards the collision state to the MCU, the FCE and the BMS; if the collision signal state is true, the VMS (VCU) guides the whole vehicle to be electrified under high voltage, the BMS/FCE immediately switches off the high-voltage relay, and the MCU executes a 0-torque instruction; if collision occurs, the VMS (VCU) needs to store the collision fault after setting the collision fault as 1 before powering off, if the vehicle is powered on again, the VMS (VCU) needs to judge the collision fault state before guiding high voltage to power on, and if the collision fault state is 1, the high voltage power on is forbidden; the collision fault can be cleared by the diagnostic instrument, and after the fault is cleared, the vehicle can be powered on at normal high voltage.

(2) High-pressure interlocking: the BMS detects the interlocking state of the high-voltage plug-in unit on the power battery pack, the fuel battery and the PCU and sends the interlocking state to the VMS (VCU); and if the VMS (VCU) receives the reported high-voltage interlocking state as 1, the fault processing is started. The current state (vehicle speed and high-voltage power-on state) of the vehicle is integrated, and the specific strategy is as follows: if the whole vehicle is in static state and does not have high voltage, the whole vehicle cannot be electrified at high voltage (the instrument lights a system fault lamp); the whole vehicle is kept still and is subjected to high voltage (the vehicle speed V is less than or equal to 5km/h), and the whole vehicle is subjected to high voltage power off (a fault lamp of a system is lightened by an instrument); the running speed of the vehicle (V >5km/h), the whole vehicle can run without limiting speed, but the instrument lights a system fault lamp; after the fault disappears, the whole vehicle can be powered on after being powered off.

(3) Insulation detection: the insulation detection task is completed by the BMS, the detection circuit is integrated in the BMS, and after high-voltage electrification is completed, the insulation resistance value detected by the BMS is the insulation resistance value of the direct-current bus of the whole vehicle and comprises a battery and all parallel high-voltage parts; the BMS needs to monitor the insulation resistance value, reports the low fault of the insulation resistance when the insulation resistance value is lower than a certain threshold value, and completes fault processing.

(4) Active discharging: after the high-voltage power failure of the vehicle, the voltage of a direct-current bus can be quickly reduced to be below 60V (DC) safe voltage within a set time through an active discharge circuit, wherein the active discharge circuit comprises an MCU (microprogrammed control unit) and a PTC (positive temperature coefficient) execution mechanism, the MCU and the PTC execute a discharge function according to a state machine, and after the high-voltage discharge state machine is detected, the MCU drives a motor winding or a resistance discharge loop to execute active discharge; the PTC controller performs active discharge by controlling the PTC heating resistor to access the bus.

(5) Passive discharge: the fuel cell vehicle should have a passive discharge function, which is performed by the MCU. The passive discharge function is realized by a discharge resistor in the MCU high-voltage circuit. After the high voltage of the power battery is cut off, the voltage of the direct current bus must be reduced to below 60V (DC) within 5min by the passive discharge function.

(6) Hydrogen safety: the hydrogen concentration in the vehicle and in the trunk is detected through the HMS, the hydrogen concentration is guaranteed not to exceed the safety warning value, a driver is reminded after the hydrogen concentration exceeds the warning concentration, and a corresponding protection strategy is carried out on the vehicle.

Claims

1. A fuel cell vehicle multiple source controller characterized by: the device comprises a core singlechip, a CAN interface filter circuit, a digital input expansion circuit, a digital output expansion circuit, an AD conversion circuit and a voltage-current conversion circuit; the CAN interface filter circuit is respectively connected with a CAN port of the core singlechip and a CAN network of the fuel cell system; the input end of the digital quantity input expansion circuit is connected with a digital quantity sensor of the fuel cell, and the output end of the digital quantity input expansion circuit is connected with the digital quantity input end of the core singlechip; the input end of the digital output expansion circuit is connected with the digital output end of the core singlechip, and the output end of the digital output expansion circuit is connected with the inductive load of the fuel cell; the input end of the AD conversion circuit is connected with an analog quantity sensor of the fuel cell, and the output end of the AD conversion circuit is connected with the analog quantity input end of the core single chip microcomputer; the input end of the voltage-current conversion circuit is connected with the analog quantity output end of the core single chip microcomputer, and the output end of the voltage-current conversion circuit is connected with the DC/DC and the frequency converter of the fuel cell; photoelectric isolation circuits are arranged among the digital input expansion circuit, the digital output expansion circuit, the analog output end, the CAN interface filter circuit and the core singlechip; the fuel cell automobile multi-source controller comprises the function of a VMS, the VMS has the function of a whole automobile controller, and the fuel cell automobile multi-source controller also has a multi-channel digital signal input channel and can acquire gear signals, key signals and clutch switching signals; the device is provided with a plurality of analog quantity input channels, and can acquire analog and digital signals such as an accelerator pedal and gear signals; the device is provided with a plurality of PWM signal acquisition channels and can acquire rotating speed sensor signals in a sine or pulse form; the fan can be controlled by a multi-path PWM output mode; the motor driving function is provided, and the throttle motor can be driven.

2. The fuel cell vehicle multiple-source controller according to claim 1, characterized in that: the digital quantity sensor comprises a gear signal sensor, a key signal sensor and a clutch switch signal sensor.

3. The fuel cell vehicle multiple-source controller according to claim 1, characterized in that: the analog quantity sensor comprises an accelerator pedal signal acquisition sensor.

4. The fuel cell vehicle multiple-source controller according to claim 1, characterized in that: the PWM signal acquisition circuit is connected with the PWM signal output circuit; the PWM signal acquisition circuit acquires a sine or pulse type rotating speed sensor signal; the PWM signal output circuit can control the fan, has a motor driving function, and can drive the throttle motor.

5. The fuel cell vehicle multiple-source controller according to claim 1, characterized in that: the communication of the CAN port adopts CANB2.0 standard, and the communication speed is 500 Kbps.