An all-in-one integrated control system for fuel cell vehicle control

Abstract

The present invention proposes an all-in-one integrated control system for controlling a fuel cell vehicle, the system comprising a DC voltage regulator converter, an all-in-one integrated controller, an air compressor controller and a water pump controller; the voltage input end of the DC voltage regulator converter is connected to the high voltage end of the fuel cell vehicle's stack; the voltage output end of the DC voltage regulator converter is respectively connected to the voltage input ends of the all-in-one integrated controller, the air compressor controller and the water pump controller; the air compressor control signal output end of the all-in-one integrated controller is connected to the control signal input end of the air compressor controller; the water pump control signal output end of the all-in-one integrated controller is connected to the control signal input end of the water pump controller.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell vehicle control, and in particular to an all-in-one integrated control system for fuel cell vehicle control. Background Art

[0002] In recent years, with the breakthrough of hydrogen fuel cell technology, the rapid development of new energy vehicles, and the country's increasing attention to clean energy, my country has begun to increase its planning and support for the field of hydrogen fuel cells. In "Made in China 2025", it is proposed to further expand the operation scale of fuel cell vehicles to 1,000 vehicles. By 2025, the supporting infrastructure such as hydrogen production and hydrogenation will be basically complete, and fuel cell vehicles will achieve regional small-scale operation. The development of hydrogen fuel cells has been elevated to a strategic level. The core technology of fuel cell vehicles lies in the net power control of fuel cell stacks and fuel cell stack accessories. However, the existing control system still has problems of low output power and poor reliability. Summary of the invention

[0003] The present invention provides an all-in-one integrated control system for fuel cell vehicle control, which is used to solve the problems of low output power and poor reliability of the existing control system. The technical solutions adopted are as follows:

[0004] An all-in-one integrated control system for fuel cell vehicle control, the system comprising a DC voltage regulator converter, an all-in-one integrated controller, an air compressor controller and a water pump controller;

[0005] The voltage input end of the DC voltage regulator is connected to the high voltage end of the fuel cell vehicle's stack; the voltage output end of the DC voltage regulator is respectively connected to the voltage input ends of the all-in-one integrated controller, the air compressor controller and the water pump controller; the air compressor control signal output end of the all-in-one integrated controller is connected to the control signal input end of the air compressor controller; the water pump control signal output end of the all-in-one integrated controller is connected to the control signal input end of the water pump controller. The power supply end of the all-in-one integrated controller is connected to the power supply end of the fuel cell vehicle's stack accessories and load, wherein the stack accessories include a hydrogen injection valve, a membrane humidifier, an air valve, a drain valve and a cooling fan.

[0006] Furthermore, the all-in-one integrated controller includes a central processing unit and a power output device; the central controller is electrically connected to the power output device; the signal output end of the power output device is connected to the power control signal input end of the battery stack accessories of the fuel cell vehicle, wherein the battery stack accessories include a hydrogen injection valve, a membrane humidifier, an air valve, a drain valve and a cooling fan;

[0007] The power output device is used to control the speed of the cooling fan and the membrane humidifier through PWM power output, and to control the opening and closing of the drain valve and the hydrogen injection valve through high-end power output.

[0008] Furthermore, the all-in-one integrated controller also includes a CAN communication device, and the all-in-one integrated controller communicates with the vehicle controller of the fuel cell vehicle through the CAN communication device.

[0009] Further, the all-in-one integrated controller also includes a first three-phase inverter and a second three-phase inverter;

[0010] The first three-phase inverter is connected to the central controller electrical appliance, and the three-phase current signal output end of the first three-phase inverter is connected to the three-phase current control signal input end of the water pump controller; the second three-phase inverter is connected to the central controller electrical appliance, and the three-phase current control signal output end of the second three-phase inverter is connected to the three-phase current control signal input end of the air compressor controller;

[0011] The first three-phase inverter is used to control the operating state of the water pump;

[0012] The second three-phase inverter is used to control the operating state of the air compressor.

[0013] Furthermore, the all-in-one integrated controller also includes an analog quantity acquisition device;

[0014] The acquisition signal input end of the analog quantity acquisition device is respectively connected to the three-phase current feedback signal end of the air compressor, the motor temperature acquisition end, the motor voltage signal acquisition end and the bus voltage signal acquisition end; the acquisition signal input end of the analog quantity acquisition device is also respectively connected to the signal input ends of the oxygen sensor, the temperature sensor and the humidity sensor inside the fuel cell stack;

[0015] The analog quantity acquisition device is used to collect the three-phase current of the air compressor, the motor temperature, motor voltage, bus voltage of the air compressor, and the oxygen concentration, humidity and temperature inside the fuel cell stack.

[0016] Furthermore, the three-loop control process of the motor position, speed and current of the air compressor of the all-in-one integrated controller includes:

[0017] The first step is to use the three-phase currents Ia, Ib, Ic and electrical angle θ of the motor, combined with the q-axis current preset value Iq_Ref and the d-axis current preset value Id_Ref to obtain the three-phase voltages Va, Vb, Vc of the motor, and input them to the three phases of the motor to complete the control of the current loop;

[0018] The second step is to use the sliding mode observer to calculate the speed feedback ω of the motor, calculate the error value between the speed feedback ω and the speed setting value Speed_Ref to obtain the speed error value, and then bring the speed error value into the PI control loop of the motor to obtain the PI loop control output result, and use the value of the output result of the PI loop control as the current preset value of the current loop control. At this time, let the d-axis current preset value Id_Ref be 0, then the q-axis current preset value Iq_Ref is equal to the output result of the PI loop control, combined with the current loop control in the first step, to complete the speed-current dual closed-loop control of the motor;

[0019] The third step is to use the sliding mode observer to calculate the current position Position (θ) of the motor, perform error calculation between the current position and the position setting value to obtain the position error value, and then bring the position error value into the P control loop of the motor to obtain the value of the P loop output result as the input speed setting value (i.e. Speed_Ref) of the motor's speed control. Combined with the speed and current dual closed-loop control in the second step, the three-closed-loop control of the motor's position, speed and current is completed.

[0020] Furthermore, the specific process of completing the current loop control in the first step includes:

[0021] Step 1, obtain the three-phase current Ia, Ib, Ic and electrical angle θ of the motor; where Ia, Ib, Ic are the sampled currents of phase A, phase B, and phase C respectively, which can be directly obtained through AD sampling. Usually, two phases are directly sampled, and the third phase is calculated using the formula Ia+Ib+Ic=0. The electrical angle θ can be calculated by a sliding mode observer;

[0022] Step 2: The three-phase currents Ia, Ib, and Ic are transformed by Clark to obtain the currents Iα, Iβ in the αβ coordinate system, and then Iα, Iβ are transformed by Park to obtain the q-axis current Iq and the d-axis current Id;

[0023] Step 3: Calculate the errors between the q-axis current Iq and the d-axis current Id and the q-axis current setting value Iq_Ref and the d-axis current setting value Id_Ref respectively to obtain the current error values ​​of the q-axis and the d-axis;

[0024] Step 4: Substitute the q-axis current error value into the q-axis current PI loop to calculate the q-axis voltage Vq, and substitute the d-axis current error value into the d-axis current PI loop to calculate the d-axis voltage Vd;

[0025] Step 5: Perform an inverse Park transformation on the q-axis voltage Vq and the d-axis voltage Vd to obtain the voltages Vα and Vβ in the αβ coordinate system;

[0026] Step 6: Use the SVPWM algorithm to obtain the three-phase voltages Va, Vb, and Vc of the motor through the three-phase inverter, and input them into the three phases of the motor to complete the control of the current loop.

[0027] Furthermore, the process of calculating the current position of the motor using the sliding mode observer includes:

[0028] Step 1: Subtract the sliding mode observer model from the state equation of the motor with the current as the state variable to obtain the current error state equation of the sliding mode observer;

[0029] Step 2, setting the input conditions of the fuzzy system of the sliding mode observer to make the current error state equation asymptotically stable, and obtaining the fuzzy switching gain, fuzzy set and fuzzy system rules of the sliding mode observer;

[0030] Step 3, using the current model when the state point reaches the sliding surface to perform sliding film motion combined with the current error state equation of the sliding mode observer to obtain an equivalent continuous switching signal;

[0031] Step 4: low-pass filter the continuous switch signal to remove high-frequency components and obtain an estimated value of back electromotive force;

[0032] Step 5: Utilize the relationship of back electromotive force in the α-β coordinate system to obtain the estimated rotor position information, and then perform phase compensation on the rotor position information to obtain the final rotor position.

[0033] Furthermore, the model structure of the sliding mode observer is as follows:

[0034]

[0035] Among them, the sliding surface of the sliding mode observer is in k(t) is the sliding mode observer gain, is the observer output; is the observation error, is the switch function.

[0036] Furthermore, the fuzzy switching gain of the sliding mode observer is:

[0037] If Then k w Become bigger;

[0038] If Then k w become smaller;

[0039] The fuzzy set of input and output items of the fuzzy system of the sliding mode observer is as follows:

[0040] For {NB NM ZO PM PB}

[0041] k w For {NB NM ZO PM PB}

[0042] in, is the input term, k w It is the output term, NB means negative big, NM means negative middle, ZO means zero, PM means positive middle, and PB means positive big;

[0043] The fuzzy system rules are:

[0044] Input The value PB corresponds to the output item Take the value PB;

[0045] Input Output item corresponding to the PM value Take the value PM;

[0046] Input The value ZO corresponds to the output item Take the value ZO;

[0047] Input The value NM corresponds to the output item The value is NM;

[0048] Input The value of NB corresponds to the output item The value is NB.

[0049] Beneficial effects of the present invention:

[0050] The present invention proposes an all-in-one integrated control system for fuel cell vehicle control. Compared with the prior art, the present invention has the following beneficial effects:

[0051] 1. Wide application: Applicable to fuel cell commercial vehicles and passenger cars to meet vehicles with different power requirements;

[0052] 2. Effectively improve the output power of fuel cell vehicles: solve the problem of low output power of fuel cell stack and net power output control;

[0053] 3. Effectively improve system reliability: realize effective control of fuel cell stacks and greatly improve the net power output efficiency of fuel cells;

[0054] 4. Easy to promote and apply: compatible with air compressors with different parameters, and no professional personnel are required to edit the code during the self-learning stage of controlling the air compressor;

[0055] 5. Effectively reduce costs: The fuel cell stack control unit, DC voltage conversion unit, power distribution unit, high-pressure water pump control and air compressor control of fuel cell vehicles are integrated into one controller, which reduces the cost of mass production and testing and improves the economy of the design; the position sensor is omitted in the air compressor control, reducing costs;

[0056] 6. The structure of the integrated control system and integrated controller is convenient for layout: Fewer controllers and wiring harnesses reduce the requirements for layout space, thus facilitating the layout of the entire vehicle and making the interior of the vehicle more concise and beautiful;

[0057] 7. The structure of the integrated control system and integrated controller facilitates maintenance: faults that may have occurred in multiple controllers are concentrated in one controller, making it easier to find and eliminate faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A wiring diagram of the all-in-one integrated control system of the invention;

[0059] Figure 2 A schematic diagram of the structure of the all-in-one integrated controller of the invention;

[0060] Figure 3 The communication topology diagram between the all-in-one integrated controller and the vehicle controller of the invention;

[0061] Figure 4 It is a three-loop block diagram of position, speed and current of the air compressor control of the all-in-one integrated controller of the present invention;

[0062] Figure 5 A membership function waveform diagram of the fuzzy input;

[0063] Figure 6 A membership function waveform diagram of the fuzzy output;

[0064] Figure 7 This is a block diagram of the sliding mode observer system of the present invention. DETAILED DESCRIPTION

[0065] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0066] The present invention proposes an all-in-one integrated control system for fuel cell vehicle control, aiming to solve the problems of low output power and poor reliability of existing control systems.

[0067] The embodiment of the present invention provides an all-in-one integrated control system for fuel cell vehicle control. Figure 1As shown, the system includes a DC voltage regulator converter, an all-in-one integrated controller, an air compressor controller and a water pump controller;

[0068] The voltage input end of the DC voltage regulator is connected to the high voltage end of the fuel cell vehicle's stack, and the voltage output end of the DC voltage regulator is also connected in parallel with the output bus of the fuel cell vehicle's battery management system; the voltage output end of the DC voltage regulator is respectively connected to the voltage input end of the all-in-one integrated controller, the air compressor controller and the water pump controller; the air compressor control signal output end of the all-in-one integrated controller is connected to the control signal input end of the air compressor controller; the water pump control signal output end of the all-in-one integrated controller is connected to the control signal input end of the water pump controller. The control signal output end of the air compressor controller is connected to the control signal input end of the air compressor, and the control signal output end of the water pump controller is connected to the control signal input end of the water pump; the voltage supply end of the all-in-one integrated controller is connected to the power supply end of the fuel cell vehicle's stack accessories and loads. Among them, the stack accessories include a hydrogen injection valve, a membrane humidifier, an air valve, a drain valve and a cooling fan. At the same time, the all-in-one integrated controller realizes the power supply distribution to each accessory and load through a PDU power distributor.

[0069] In this embodiment, the high-voltage wiring interface of the all-in-one integrated control system includes the high-voltage positive electrode and the high-voltage negative electrode of the fuel cell stack, wherein the high-voltage positive electrode and the high-voltage negative electrode of the fuel cell stack are the high-voltage ends of the fuel cell vehicle stack mentioned above; the high-voltage positive electrode and the high-voltage negative electrode of the battery management system; the three high-voltage interfaces U, V, and W of the water pump drive, which are the above-mentioned water pump control signal output ends; the three high-voltage interfaces U, V, and W of the air compressor drive, which are the above-mentioned air compressor control signal output ends; and the high-voltage power supply positive and negative electrodes for powering other accessories, and the positive and negative electrode interfaces for powering other loads.

[0070] The all-in-one control system is equipped with a DC voltage converter, which is a DC-DC converter whose function is to convert the fuel cell voltage into a stable voltage output. The all-in-one control system is compatible with the power distribution function to meet the different voltage power supply requirements of the air compressor controller, high-pressure water pump controller, fuel cell stack accessories (hydrogen injection valve, membrane humidifier, air valve, drain valve, cooling fan) and external loads.

[0071] like Figure 2 As shown, the all-in-one integrated controller includes a central processing unit and a power output device; the central controller is electrically connected to the power output device; the signal output end of the power output device is connected to the power control signal input end of the battery stack accessories of the fuel cell vehicle, wherein the battery stack accessories include a hydrogen injection valve, a membrane humidifier, an air valve, a drain valve and a cooling fan;

[0072] The power output device is used to control the speed of the cooling fan and the membrane humidifier through a PWM (pulse width modulation) power output control method, and to control the opening and closing of the drain valve and the hydrogen injection valve through a high-end power output control method, wherein the high-end output control means that when the drain valve and the hydrogen injection valve are controlled to open, the power output device is required to output a high level to be valid.

[0073] The all-in-one integrated controller also includes a CAN communication device, and the all-in-one integrated controller communicates with the vehicle controller of the fuel cell vehicle through the CAN communication device. Figure 3 As shown in the figure, the communication between the all-in-one integrated controller of the fuel cell vehicle control and other components of the fuel cell vehicle adopts the CAN communication mode. The all-in-one controller receives the control signal from the vehicle controller and sends the operating status of the air compressor, the fuel cell engine cooling high-pressure water pump and the controller to the vehicle controller.

[0074] In addition, the all-in-one integrated controller also includes a first three-phase inverter, a second three-phase inverter and an analog quantity acquisition device;

[0075] The first three-phase inverter is connected to the central controller electrical appliance, and the three-phase current signal output end of the first three-phase inverter is connected to the three-phase current control signal input end of the water pump controller; the second three-phase inverter is connected to the central controller electrical appliance, and the three-phase current control signal output end of the second three-phase inverter is connected to the three-phase current control signal input end of the air compressor controller;

[0076] The first three-phase inverter is used to control the operating state of the water pump;

[0077] The second three-phase inverter is used to control the operating state of the air compressor.

[0078] The acquisition signal input end of the analog quantity acquisition device is respectively connected to the three-phase current feedback signal end of the air compressor, the motor temperature acquisition end, the motor voltage signal acquisition end and the bus voltage signal acquisition end; the acquisition signal input end of the analog quantity acquisition device is also respectively connected to the signal input ends of the oxygen sensor, the temperature sensor and the humidity sensor inside the fuel cell stack;

[0079] The analog quantity acquisition device is used to collect the three-phase current of the air compressor, the motor temperature, motor voltage, bus voltage of the air compressor, and the oxygen concentration, humidity and temperature inside the fuel cell stack.

[0080] In this embodiment, the interfaces of the all-in-one controller include:

[0081] Low-voltage signal input signal interface, specifically including the A-phase current signal interface, B-phase current signal interface, and C-phase current signal interface of the air compressor controller; water pump operation status signal interface;

[0082] From the external sensor interface, including the signal interface of the oxygen concentration sensor, humidity sensor and temperature sensor inside the fuel cell;

[0083] The output signal interface includes: cooling fan speed signal controlled by PWM power output, drain valve opening and closing signal controlled by high-end power output; membrane humidifier signal controlled by PWM power output; opening and closing signals of several Peak-holdl type hydrogen injection valves. In addition to these signals input and output through hard wires, the all-in-one controller also has a CAN bus for receiving VCU power request signals, start signals, and power-off signals, and feedbacks the water pump operation status, air compressor operation status, battery stack operation status, and all-in-one control status signals to the VCU through the CAN bus.

[0084] The all-in-one integrated controller controls the speed of the air compressor and the high-pressure water pump through data processing of the central controller, and controls the operating status of the accessories of the fuel cell stack such as the hydrogen injection valve, membrane humidifier, air valve, drain valve, and cooling fan in real time. It collects the concentration and humidity of hydrogen and oxygen inside the fuel cell stack, the temperature, voltage and bus voltage information of the air compressor when the air compressor is running, and the status information of the high-pressure water pump when the high-pressure water pump is running, and sends it to the vehicle controller. The all-in-one integrated controller controls the operating status of the high-pressure water pump according to the status of the fuel cell stack, and monitors the operating status of the high-pressure water pump and sends its status information to the vehicle controller in real time. The all-in-one integrated controller sends its own operating status information, such as controller temperature, fault level, self-test status, etc., to the vehicle controller in real time.

[0085] The three-loop control process of the motor position, speed and current of the air compressor of the all-in-one integrated controller includes:

[0086] The first step is to use the three-phase currents Ia, Ib, Ic and electrical angle θ of the motor, combined with the q-axis current preset value Iq_Ref and the d-axis current preset value Id_Ref to obtain the three-phase voltages Va, Vb, Vc of the motor, and input them to the three phases of the motor to complete the control of the current loop;

[0087] The second step is to use the sliding mode observer to calculate the speed feedback ω of the motor, calculate the error value between the speed feedback ω and the speed setting value Speed_Ref to obtain the speed error value, and then bring the speed error value into the PI control loop of the motor to obtain the PI loop control output result, and use the value of the output result of the PI loop control as the current preset value of the current loop control. At this time, let the d-axis current preset value Id_Ref be 0, then the q-axis current preset value Iq_Ref is equal to the output result of the PI loop control, combined with the current loop control in the first step, to complete the speed-current dual closed-loop control of the motor;

[0088] The third step is to use the sliding mode observer to calculate the current position Position (θ) of the motor, perform error calculation between the current position and the position setting value to obtain the position error value, and then bring the position error value into the P control loop of the motor to obtain the value of the P loop output result as the input speed setting value (i.e. Speed_Ref) of the motor's speed control. Combined with the speed and current dual closed-loop control in the second step, the three-closed-loop control of the motor's position, speed and current is completed.

[0089] The all-in-one integrated controller proposed in this embodiment controls the air compressor speed through three closed-loop controls of position, speed, and current. The core of controlling the air compressor speed is to obtain the position signal of the position sensorless air compressor based on the sliding mode observer. The sliding mode observer makes the algorithm more reliable and simplifies the system.

[0090] The specific process of completing the current loop control in the first step includes:

[0091] Step 1, obtain the three-phase current Ia, Ib, Ic and electrical angle θ of the motor; where Ia, Ib, Ic are the sampled currents of phase A, phase B, and phase C respectively, which can be directly obtained through AD sampling. Usually, two phases are directly sampled, and the third phase is calculated using the formula Ia+Ib+Ic=0. The electrical angle θ can be calculated by a sliding mode observer;

[0092] Step 2: The three-phase currents Ia, Ib, and Ic are transformed by Clark to obtain the currents Iα, Iβ in the αβ coordinate system, and then Iα, Iβ are transformed by Park to obtain the q-axis current Iq and the d-axis current Id;

[0093] Step 3: Calculate the errors between the q-axis current Iq and the d-axis current Id and the q-axis current setting value Iq_Ref and the d-axis current setting value Id_Ref respectively to obtain the current error values ​​of the q-axis and the d-axis;

[0094] Step 4: Substitute the q-axis current error value into the q-axis current PI loop to calculate the q-axis voltage Vq, and substitute the d-axis current error value into the d-axis current PI loop to calculate the d-axis voltage Vd;

[0095] Step 5: Perform an inverse Park transformation on the q-axis voltage Vq and the d-axis voltage Vd to obtain the voltages Vα and Vβ in the αβ coordinate system;

[0096] Step 6: Use the SVPWM algorithm to obtain the three-phase voltages Va, Vb, and Vc of the motor through the three-phase inverter, and input them into the three phases of the motor to complete the control of the current loop.

[0097] The process of calculating the current position of the motor using the sliding mode observer in the third step includes:

[0098] Step 1: Subtract the sliding mode observer model from the state equation of the motor with the current as the state variable to obtain the current error state equation of the sliding mode observer;

[0099] Step 2, setting the input conditions of the fuzzy system of the sliding mode observer to make the current error state equation asymptotically stable, and obtaining the fuzzy switching gain, fuzzy set and fuzzy system rules of the sliding mode observer;

[0100] Step 3, using the current model when the state point reaches the sliding surface to perform sliding film motion combined with the current error state equation of the sliding mode observer to obtain an equivalent continuous switching signal;

[0101] Step 4: low-pass filter the continuous switch signal to remove high-frequency components and obtain an estimated value of back electromotive force;

[0102] Step 5: Utilize the relationship of back electromotive force in the α-β coordinate system to obtain the estimated rotor position information, and then perform phase compensation on the rotor position information to obtain the final rotor position.

[0103] In this embodiment, the overall process of the sliding mode observer construction process and the motor position acquisition process is as follows:

[0104] This embodiment uses a permanent magnet synchronous air compressor, whose AC and DC axis magnetic circuits are symmetrical, so the AC and DC axis inductances are equal, that is, L d =L q =L s The voltage-current equation of SPMSM in rotating coordinates is:

[0105]

[0106] The mathematical equation in the rotating coordinate system is transformed into the two-phase stationary coordinate system, and the state equation with current as the state variable is:

[0107]

[0108]

[0109] In the formula, R s is the stator phase resistance; L s is the stator phase inductance; i α ,i β ,u α ,u β , e α , e β are the current, voltage and back electromotive force in the stationary coordinate system respectively; Ψ f is the magnetic flux of the rotor permanent magnet; ω r is the rotor angular velocity.

[0110] The sliding surface is defined as in According to the design method of sliding mode variable structure control,

[0111] Taking the motor stator current as the state variable, the sliding mode observer is designed as follows:

[0112]

[0113] Where k(t) is the sliding mode observer gain, is the observer output; is the observation error,

[0114] is the switch function.

[0115] Subtracting equation (4) from equation (2), the current error state equation of the sliding mode observer can be expressed as:

[0116]

[0117] If the error equation of formula (5) is asymptotically stable, it should satisfy:

[0118]

[0119] Substituting formula (6) into formula (5), we have:

[0120]

[0121]

[0122] because Then the condition satisfying (7) is:

[0123] K(t)>|e s |, that is, K(t)>max(|e α |,|e β |) (8)

[0124] If (6) holds, that is, the arrival condition of the sliding mode is met, then the error equation (5) is asymptotically stable, which can ensure the convergence of the observation equation (4). According to the conditions of equation (8), the sliding mode gain k w must be greater than the magnitude of the back EMF, but too large a k w It will aggravate the system's chattering and increase the estimation error. In order to ensure the stability of the system and high estimation accuracy, the fuzzy switching gain is set to:

[0125] If Then k w Get bigger

[0126] If Then k w Smaller

[0127] Based on this, we can design With k w In this system, is the input term, k w is the output term. The fuzzy set definitions of the input and output terms of the fuzzy system are as follows:

[0128] For {NB NM ZO PM PB}

[0129] k w For {NB NM ZO PM PB}

[0130] Among them, NB means negative big, NM means negative middle, ZO means zero, PM means positive middle, and PB means positive big. The input of the fuzzy system is Figure 5 shown.

[0131] k w The output term membership function of the fuzzy system is Figure 6 As shown in:

[0132] The fuzzy system rules designed based on experience are shown in Table 1:

[0133] Table 1 Fuzzy system rules

[0134]

[0135] When the state point reaches the sliding surface and performs sliding motion, then:

[0136]

[0137] Substituting equation (9) into equation (5), we can get the equivalent continuous switching signal:

[0138]

[0139] make z is the switching signal of the current error, which contains the back-EMF information and the distortion caused by the switch. After low-pass filtering to remove the high-frequency components, the estimated back-EMF value can be obtained:

[0140]

[0141] Where ω c is the cutoff frequency of the low-pass filter.

[0142] From the relationship between the back electromotive force in the α-β coordinate system in formula (3), the estimated rotor position information can be obtained:

[0143]

[0144] Although low-pass filters can effectively filter out high-frequency components, they will also cause phase delay in the output. From the amplitude-frequency characteristics of low-pass filters, we can see that for fixed-frequency signals, the lower the filter cutoff frequency and the closer it is to the signal frequency, the better the filtering effect, but the corresponding phase delay will be greater. The final rotor position can only be obtained after phase compensation

[0145]

[0146] The position estimation structure based on the sliding mode observer is as follows Figure 7 The main part of the system is the sliding mode observer. The deviation between the estimated value and the measured value of the stator current is input into the switch control function, and a continuous switch signal z is output. After low-pass filtering, z is used to obtain the estimated back electromotive force. according to The estimated rotor position is derived from the relationship between the components of Then add the corresponding phase compensation value Δθ to get the final rotor position

[0147] Based on this sliding mode observer method, the position signal of the position sensorless air compressor is acquired, and the air compressor position signal is substituted into the three-loop control of position, speed and current, finally realizing the effective control of the air compressor speed by the all-in-one controller.

[0148] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An all-in-one integrated control system for fuel cell vehicle control, characterized in that: The system includes a DC voltage regulator converter, an all-in-one integrated controller, an air compressor controller and a water pump controller; The voltage input end of the DC voltage regulator is connected to the high voltage end of the fuel cell stack of the fuel cell vehicle; the voltage output end of the DC voltage regulator is respectively connected to the voltage input ends of the all-in-one integrated controller, the air compressor controller and the water pump controller; the air compressor control signal output end of the all-in-one integrated controller is connected to the control signal input end of the air compressor controller; the water pump control signal output end of the all-in-one integrated controller is connected to the control signal input end of the water pump controller; The all-in-one integrated controller includes a central processing unit and a power output device; the central processing unit is electrically connected to the power output device; the signal output end of the power output device is connected to the power control signal input end of the battery stack accessories of the fuel cell vehicle, wherein the battery stack accessories include a hydrogen injection valve, a membrane humidifier, an air valve, a drain valve and a cooling fan; The power output device is used to control the speed of the cooling fan and the membrane humidifier through PWM power output, and to control the opening and closing of the drain valve and the hydrogen injection valve through high-end power output; The all-in-one integrated controller also includes a first three-phase inverter and a second three-phase inverter; The first three-phase inverter is connected to the central processing unit electrical appliance, and the three-phase current signal output end of the first three-phase inverter is connected to the three-phase current control signal input end of the water pump controller; the second three-phase inverter is connected to the central processing unit electrical appliance, and the three-phase current control signal output end of the second three-phase inverter is connected to the three-phase current control signal input end of the air compressor controller; The first three-phase inverter is used to control the operating state of the water pump; The second three-phase inverter is used to control the operating state of the air compressor; The all-in-one integrated controller also includes an analog quantity acquisition device; The acquisition signal input end of the analog quantity acquisition device is respectively connected to the three-phase current feedback signal end of the air compressor, the motor temperature acquisition end, the motor voltage signal acquisition end and the bus voltage signal acquisition end; the acquisition signal input end of the analog quantity acquisition device is also respectively connected to the signal output ends of the oxygen sensor, the temperature sensor and the humidity sensor inside the fuel cell stack; The analog quantity acquisition device is used to collect the three-phase current of the air compressor, the motor temperature, motor voltage, bus voltage of the air compressor, and the oxygen concentration, humidity and temperature inside the fuel cell stack; The three-loop control process of the motor position, speed and current of the air compressor of the all-in-one integrated controller includes: The first step is to use the three-phase currents Ia, Ib, Ic and the electrical angle θ of the motor, combined with the q-axis current preset value Iq_Ref and the d-axis current preset value Id_Ref to obtain the three-phase voltages Va, Vb, Vc of the motor, and input them to the three phases of the motor to complete the control of the current loop; The second step is to use the sliding mode observer to calculate the speed feedback ω of the motor, calculate the error value between the speed feedback ω and the speed setting value Speed_Ref to obtain the speed error value, and then bring the speed error value into the PI control loop of the motor to obtain the PI loop control output result, and use the value of the output result of the PI loop control as the current preset value of the current loop control. At this time, let the d-axis current preset value Id_Ref be 0, then the q-axis current preset value Iq_Ref is equal to the output result of the PI loop control, combined with the current loop control in the first step, to complete the speed-current dual closed-loop control of the motor; The third step is to use the sliding mode observer to calculate the current position Position (θ) of the motor, perform error calculation between the current position and the position setting value to obtain a position error value, and then bring the position error value into the P control loop of the motor to obtain the value of the P loop output result as the input speed setting value of the motor speed control, combined with the speed and current double closed-loop control in the second step, to complete the three-closed-loop control of the motor position, speed and current; The process of calculating the current position of the motor using the sliding mode observer includes: Step 1: Subtract the sliding mode observer model from the state equation of the motor with the current as the state variable to obtain the current error state equation of the sliding mode observer; Step 2, setting the input conditions of the fuzzy system of the sliding mode observer to make the current error state equation asymptotically stable, and obtaining the fuzzy switching gain, fuzzy set and fuzzy system rules of the sliding mode observer; Step 3, using the current model when the state point reaches the sliding surface to perform sliding film motion combined with the current error state equation of the sliding mode observer to obtain an equivalent continuous switching signal; Step 4: low-pass filter the continuous switch signal to remove high-frequency components and obtain an estimated value of back electromotive force; Step 5: Utilization α - β The relationship between the back electromotive force in the coordinate system is used to obtain the estimated rotor position information, and then the rotor position information is phase compensated to obtain the final rotor position.

2. The all-in-one integrated control system according to claim 1, characterized in that: The all-in-one integrated controller also includes a CAN communication device, and the all-in-one integrated controller communicates with the vehicle controller of the fuel cell vehicle through the CAN communication device.

3. The all-in-one integrated control system according to claim 1, characterized in that: The specific process of completing the current loop control described in the first step includes: Step 1: Obtain the three-phase currents Ia, Ib, Ic and electrical angle θ of the motor; Step 2: The three-phase currents Ia, Ib, and Ic are transformed by Clark to obtain the currents Iα and Iβ in the αβ coordinate system, and then Iα and Iβ are transformed by Park to obtain the q-axis current Iq and the d-axis current Id; Step 3: Calculate the errors between the q-axis current Iq and the d-axis current Id and the q-axis current setting value Iq_Ref and the d-axis current setting value Id_Ref respectively to obtain the current error values ​​of the q-axis and the d-axis; Step 4: Substitute the q-axis current error value into the q-axis current PI loop to calculate the q-axis voltage Vq, and substitute the d-axis current error value into the d-axis current PI loop to calculate the d-axis voltage Vd; Step 5: Perform an inverse Park transformation on the q-axis voltage Vq and the d-axis voltage Vd to obtain the voltages Vα and Vβ in the αβ coordinate system; Step 6: Use the SVPWM algorithm to obtain the three-phase voltages Va, Vb, and Vc of the motor through the three-phase inverter, and input them into the three phases of the motor to complete the control of the current loop.

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