CN102616148B - Range extended electric vehicle control system and method - Google Patents

Abstract

The invention discloses a range extender control system and a complete vehicle control system for an extended-range electric vehicle, which include a traditional throttle-controlled engine, a generator integrated with drive and power generation functions integrally connected to the engine crankshaft, a vehicle-mounted power battery, Vehicle controller, range extender controller, battery management system, battery DC current sensor, engine controller, generator controller, generator terminal DC current sensor, permanent magnet synchronous drive motor, power battery and generator are connected together The power line is used to drive the wheels, motor controller, motor DC current sensor, throttle, crankshaft position sensor, the range extender controller communicates with the engine controller and generator controller to send control commands, and the range extender controller according to The driver's demand and the state of the range extender system are used for power generation energy management and auxiliary system control. The invention also discloses a control method for the extended-range electric vehicle. Can be used in electric vehicles.

Description

A control system and control method for an extended-range electric vehicle

technical field

The invention relates to the technical field of electric vehicles, in particular to a control system and a control method for an extended-range electric vehicle.

Background technique

The driving range of pure electric vehicles is the performance gap between current pure electric vehicles and traditional vehicles. The design concept and usage method of the extended-range electric vehicle just make up for the insufficient driving range of pure electric vehicles, but the existing technology extended-range electric vehicles have problems such as low power density and large vibration and noise.

Contents of the invention

The purpose of the present invention is to develop a range extender system that satisfies the requirements of the range-extended electric vehicle on the basis of the existing engine control system and generator control system without re-development and calibration of the engine controller ECU and generator controller GCU. Control schemes and methods for functional requirements.

In order to solve the above problems, an extended-range electric vehicle control system includes a traditional throttle-controlled engine, a generator integrating drive and power generation functions integrated with the engine crankshaft, a vehicle-mounted power battery, a vehicle controller, and a range-extended controller, battery management system, battery DC current sensor, engine controller, generator controller, generator terminal DC current sensor, permanent magnet synchronous drive motor, power battery and generator connected together in the power line for driving wheels, Motor controller, motor DC current sensor, throttle, crankshaft position sensor, engine flywheel and generator rotor are rigidly connected through mechanical devices, inverter power components are integrated in the generator controller, and the generator is connected to the high-voltage bus through the generator controller , the power battery can be charged through DC/DC, the drive motor can be powered through the motor controller, and the drive motor is directly connected to the wheel through the mechanical gearbox. The controller communicates with the generator controller and sends control instructions, and the range extender controller performs power generation energy management and auxiliary system control according to the driver's demand and the state of the range extender system.

Further, as a preferred solution, the power battery of the system can be charged externally through the on-board charger, the working state of the range extender is controlled by the vehicle controller, and the range extender charges the power battery or supplies power to the driving motor or provides auxiliary power. The mechanical power of the system.

The invention also discloses a control method for an extended-range electric vehicle, which includes the following steps: the vehicle controller collects signals from the driver's key position, pedal position, gear position, auxiliary system demand button signal, the current battery SOC and the allowed charge of the battery. Discharge current information to determine whether to start the range extender and the working mode of the range extender:

If it is satisfied: battery SOC < 30% or air conditioner request is 1 or heating request is 1 or battery SOC < 90% and accelerator pedal opening > 80%, after the conditions are met, the range extender start request is set to 1; and condition 2 is met : The key door position is in the On gear and the accelerator pedal position is > 2%, the range extender shutdown request is set to 0; if the above two conditions are met, the range extender enters the start mode;

After entering the startup mode for 50ms, judge whether the engine speed is greater than 800rpm, and enter the range extender working mode after meeting the conditions;

If satisfied: 30%<SOC<=90% and accelerator pedal opening>80%, enter range extender acceleration control mode; if meet 30%<SOC<=90% and accelerator pedal opening<50% exit range extender acceleration control mode;

If it is satisfied: SOC <= 30% and statistical vehicle speed < calibrated vehicle speed 1, enter the control mode of the first power generation operating point of the range extender;

If it is satisfied: SOC <= 30% and statistical vehicle speed > calibrated vehicle speed 2, enter the second power generation operating point control mode of the range extender;

If it is satisfied: SOC > 45% and the air conditioner request is 1, enter the idle speed working point 2 of the range extender;

If it is satisfied: SOC > 45% and the warm air request is 1, enter the range extender idle speed working point 1;

If it meets: SOC>45% and heating request is 0 and air conditioning request is 0 and accelerator pedal<80% or condition 2 is met: key door position is in Acc gear and accelerator pedal position<2 and generator speed<1, extend the range Set the generator off request to 1 to enter the shutdown mode of the range extender; if it is satisfied: detect that the life signal of the generator is 0 and enter the shutdown mode of the range extender.

Further, as a preferred solution, the vehicle controller first judges the driving intention and the state of the range extender, and judges the mode in which the range extender should work according to the driver's gear position signal and pedal signal: the range extender is off, the range extender Range extender start, range extender power generation operating point 1, range extender power generation operating point 2, range extender idle speed operating point 1, range extender idle speed operating point 2, range extender acceleration assist point, range extender shutdown; working conditions After the judgment is completed, the range extender controller performs coordinated control of the engine and generator according to the mode command of the vehicle controller.

Further, as a preferred solution, the starting control mode of the range extender is: the generator works in the electric speed control mode, starts the engine at 800rpm, detects that the generator speed is greater than 750rpm, sends the engine ignition switch signal, and detects that the engine speed is greater than 850rpm And less than 1450rpm, the generator enters the control mode with rotation.

Further, as a preferred solution, the shutdown control mode of the range extender is as follows: send the target generator speed to 0, detect that the generator speed is lower than 800rpm, turn off the engine ignition switch signal, detect that the generator speed is lower than 5rpm, and turn off Generator high voltage control relay, close generator low voltage relay after 50ms.

Further, as a preferred solution, the constant power generation control mode of the range extender is: the engine works in a torque closed-loop control mode, and the generator works in a speed control mode. According to the calibrated generator operating point, corresponding to the target speed of the generator and the target working torque of the engine, the power balance is achieved. According to the calibrated open-link valve position, the range extender controller collects the actual torque fed back by the generator as the closed-loop control reference value and the target torque difference, and corrects the open-link valve position. The generator always works in the speed control mode. The range extender controller sends the target speed to the generator controller with a gradient of 1000rpm/s according to the target speed. The acceleration control mode of the range extender is also a kind of constant power generation control, and the generated power is different from the constant power operating point one. And work 2, once the range extender is already in the constant power generation operating point 1 or 2, it will not control the acceleration working mode.

Further, as a preferred solution, the idling mode of the range extender: to meet the driver’s cooling and heating requirements for the passenger compartment, to drive the air conditioner compressor and to warm up the engine at idling speed to provide warm air. At these two operating points, the engine works In the speed control mode, the generator is in the state of random rotation, and does not provide electric power for the power battery and the drive motor.

Due to the use of the extended-range structure, the control process of the extended-range electric vehicle range extender, based on the technical characteristics of the existing engine and generator, does not need to redesign and develop the calibration ECU and GCU through the extended-range controller controller to coordinate and control to meet the overall requirements. The car's functional requirements for the range extender. The working mode control strategy of the range extender can switch the power generation operating point according to the driving conditions; it can supplement the characteristics of insufficient discharge rate of the power battery. Brake energy recovery and range extender energy management control strategy. Energy management control is carried out for the purpose of maximizing the utilization of recovered energy and saving the fuel consumption of the engine during recovery.

Description of drawings

A more complete and better understanding of the invention, and many of its attendant advantages, will readily be learned by reference to the following detailed description when considered in conjunction with the accompanying drawings, but the accompanying drawings illustrated herein are intended to provide a further understanding of the invention and constitute A part of the present invention, the exemplary embodiment of the present invention and its description are used to explain the present invention, and do not constitute an improper limitation of the present invention, wherein:

Figure 1 is a block diagram of the vehicle control system and the range extender control system;

Figure 2 is a flow chart of the control of the range extender.

Detailed ways

Embodiments of the present invention will be described below with reference to FIGS. 1-2.

In order to make the above objects, features and advantages more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

As shown in Figure 1, an extended-range electric vehicle control system includes a traditional throttle-controlled engine 2, a generator 5 integrated with drive and power generation functions integrally connected to the engine crankshaft, a vehicle-mounted power battery 14, and a complete vehicle Controller 12, range extender controller 7, battery management system 15, battery DC current sensor 13, engine controller 4, generator controller 6, generator terminal DC current sensor 8, permanent magnet synchronous drive motor 11 and power battery 14 and the generator 5 are connected together in the power line for driving the wheels, the motor controller 10, the motor DC current sensor 9, the throttle valve 1, the crankshaft position sensor 3, the flywheel of the engine 2 and the rotor of the generator 5 are rigidly connected through a mechanical device to generate electricity The inverter power element is integrated in the motor controller 6, the generator 5 is connected to the high-voltage bus through the generator controller 6, the power battery 14 can be charged through DC/DC, and the driving motor 11 is powered through the motor controller 10, and the driving motor 11 It is directly connected to the wheels through a mechanical gearbox, wherein the engine 2 and the generator 5 are collectively referred to as a range extender, and the range extender controller 7 communicates with the engine controller 4 and the generator controller 6 and sends control instructions. The controller 7 performs power generation energy management and auxiliary system control according to the driver's demand and the state of the range extender system.

The power battery pack 14 adopts a storage battery with both energy and power, which must not only meet the requirements of a certain driving range, but also meet the frequent charging capacity of 1.5C-2.5C. The rechargeable battery management system 15 (BMS) monitors the current, voltage, depth of discharge, battery temperature, etc. of the power battery pack during charging and discharging, and maintains the consistency between single batteries. The drive motor 11 is the only power plant for pure electric vehicle travel. When the range-extending electric vehicle works in the range-extending mode (the range extender is turned on), the power of the range extender is to meet the average power demand of the drive motor as much as possible, and the power battery 14 is used to meet the functional requirements of the instantaneous charging and discharging power.

The main control units of the range extender control system include the range extender controller 7 (RE_Controller), the engine controller 4 (ECU) and the generator controller 6 (GCU). The engine controller 4 (ECU) is the original traditional engine 2, which has various control functions of the traditional engine: open-loop control of idle speed, closed-loop control of torque, detection of the current working state of the engine, fan control relay, oil pump relay control, air-conditioning clutch control , Fault detection and so on. The engine controller 4 (ECU) receives the accelerator pedal analog signal from the range extender controller 7 (RE_Controller) to control the throttle, and then realizes different load control of the engine and changes the mechanical input power of the range extender. The generator controller 4 (GCU) has a speed control mode and a follow-up mode, corresponding to the target speed command and mode command from the range extender controller 7 (RE_Controller), starts the engine, and provides the engine with load torque or follow-up rotation. By changing the target speed of the generator and changing the load of the engine, the generated power of the range extender is finally changed. RE_Controller7 is used to receive work instructions from the vehicle controller, set the engine torque and engine speed corresponding to different power generation according to the minimum fuel economy curve of the engine, analyze the state and target instructions of the engine and generator, and coordinate ECU4 and GCU6 Reach the working state of the vehicle controller's demand for the range extender. The target operating speed of the engine in the system is defined in the minimum fuel consumption area of the engine, and the target generating power of the generator is defined in the range between the engine speed and the base speed of the generator. Among them, the control of the engine throttle 1 is used to control the engine load at the set generating power, and quickly find the control position of the engine throttle 1 through the target generating speed point. When the range extender is switched at the working point, it is necessary to avoid the speed of the engine from overshooting.

Example 2

As shown in Figure 2, a method for controlling an extended-range electric vehicle comprises the following steps:

S1. The vehicle controller collects information from the driver's key position, pedal position, gear position, auxiliary system demand button signal, battery current SOC and charge and discharge current information allowed by the battery, and judges whether it is necessary to start the range extender and the range extender. Operating mode:

S2. If it is satisfied: battery SOC<30% or air conditioner request is 1 or heater request is 1 or battery SOC<90% and accelerator pedal opening is more than 80%, after the conditions are met, the range extender start request is set to 1; and it is satisfied Condition 2: The key door position is in the On gear and the accelerator pedal position is > 2%, and the range extender shutdown request is set to 0; if the above two conditions are met, the range extender enters the start mode;

S3. After entering the startup mode for 50ms, judge whether the engine speed is greater than 800rpm, and enter the range extender working mode after meeting the conditions;

S4. If it is satisfied: 30%<SOC<=90% and the accelerator pedal opening>80%, enter the range extender acceleration control mode; if it meets 30%<SOC<=90% and the accelerator pedal opening<50%, exit the range extender accelerator acceleration control mode;

S5. If it is satisfied: SOC <= 30% and statistical vehicle speed < calibrated vehicle speed 1, enter the control mode of the first power generation operating point of the range extender;

S6. If it satisfies: SOC<=30% and statistical vehicle speed>Calibrated vehicle speed 2 Enter the second power generation operating point control mode of the range extender;

S7. If it is satisfied: SOC > 45% and the air conditioner request is 1, enter the idle speed working point 2 of the range extender;

S8. If it is satisfied: SOC > 45% and the warm air request is 1, enter the idle speed working point 1 of the range extender;

S9. If it is satisfied: SOC>45% and heating request is 0 and air conditioning request is 0 and accelerator pedal<80% or condition 2 is met: key door position is in Acc gear and accelerator pedal position<2 and generator speed<1, The range extender shutdown request is set to 1, and the range extender shutdown mode is entered;

S10. If it is satisfied: detect that the life signal of the generator is 0 and enter the range extender shutdown mode.

The vehicle controller first judges the driving intention and the state of the range extender, and judges the working mode of the range extender according to the driver's gear signal and pedal signal: the range extender is off, the range extender is started, and the range extender generates power. Operating point 1, range extender power generation operating point 2, range extender idling operating point 1, range extender idling operating point 2, range extender acceleration assist point, range extender shutdown; after the working condition judgment is completed, the range extender controls The controller performs coordinated control of the engine and generator according to the mode command of the vehicle controller.

The start control mode of the range extender is: the generator works in the electric speed control mode, starts the engine at 800rpm, detects that the generator speed is greater than 750rpm, sends the engine ignition switch signal, detects that the engine speed is greater than 850rpm and less than 1450rpm, and the generator enters the follow-up control model.

The start control mode of the range extender is: the generator works in the electric speed control mode, starts the engine at 800rpm, detects that the generator speed is greater than 750rpm, sends the engine ignition switch signal, detects that the engine speed is greater than 850rpm and less than 1450rpm, and the generator enters the follow-up control model.

The stop control mode of the range extender is: send the generator target speed to 0, detect that the generator speed is lower than 800rpm, turn off the engine ignition switch signal, detect that the generator speed is lower than 5rpm, turn off the generator high voltage control relay, and turn off the generator after 50ms Machine low voltage relay.

The constant power generation control mode of the range extender is: the engine works in the torque closed-loop control mode, and the generator works in the speed control mode. According to the calibrated generator operating point, corresponding to the target speed of the generator and the target working torque of the engine, the power balance is achieved. According to the calibrated open-link valve position, the range extender controller collects the actual torque fed back by the generator as the closed-loop control reference value and the target torque difference, and corrects the open-link valve position. The generator always works in the speed control mode. The range extender controller sends the target speed to the generator controller with a gradient of 1000rpm/s according to the target speed. The acceleration control mode of the range extender is also a kind of constant power generation control, and the generated power is different from the constant power operating point one. And work 2, once the range extender is already in the constant power generation operating point 1 or 2, it will not control the acceleration working mode.

Range extender idling working mode: meet the driver’s cooling and heating needs for the passenger compartment, drive the air conditioner compressor and idle warm-up to provide warm air. At these two working points, the engine works in the speed control mode, and the generator is in random rotation State, does not provide electric power for the power battery and drive motor.

The control of the range extender is mainly to coordinate the control of the engine and generator according to the power demand of the whole vehicle for the range extender. The main control quantity of the engine system is the throttle valve of the engine. The engine throttle 1 is controlled by a stepping motor and is not directly mechanically connected with the accelerator pedal. The throttle position sensor is directly connected with the stepper motor to detect the throttle angle and perform open-loop and closed-loop control of the throttle.

The important control parameter for engine system startup control is the idle speed reference speed calculated by the crankshaft position sensor 3 and the ECU feedback. In the start-up phase, RE_Controller not only needs to detect the current engine speed, but also compares it with the idle speed reference speed fed back by the ECU. In order to avoid the sudden change and sudden increase in the speed of the range extender system caused by the instant the engine is ignited, the generator needs to control the speed according to the reference idle speed to provide stable engine torque sudden change caused by ignition. When the detected engine speed is greater than 800rpm and lower than 1450rpm, it is considered that the engine has entered the idling condition.

In addition, the cooling water temperature of the engine system is an important factor affecting the control effect of the entire system. The cooling water temperature of the engine affects the emission and fuel economy of the engine, and affects the stability of the throttle control effect. The system disturbance caused by the opening and closing of the cooling fan is an important external disturbance of the stable operating point. Due to the temperature of the system, the open-loop control of the throttle valve cannot be used for operating points other than idle speed. The feedback control parameter adopted by the system is the load torque fed back by the generator controller. The engine throttle is interpolated according to the target operating speed to obtain the open-loop control throttle parameters, and the closed-loop PID adjustment of the target power generation is performed through the torque parameters fed back by the generator in real time.

The current sensor 8 is used to detect the magnitude of the current at the DC output terminal of the generator controller, and the current sensor 13 is used to detect the magnitude of the current at the output terminal of the battery. The current detected by sensor 8 is used by RE_Controller to observe the actual power generated by the generator, and the current detected by sensor 13 is used to detect the current charging and discharging status of the power battery and detect faults to protect the battery from overcharging or overdischarging.

The energy management method for the coordinated work of braking energy recovery and range extender:

When the range extender is not working, formulate the braking energy recovery strategy according to the charging current allowed by the battery. When the range extender is in the working state, RE_Controller controls the engine throttle to be fully closed, and the generator speed is in the state of random rotation. When it does not generate electricity, it cannot charge the battery pack, so it will not cause the problem of short-term overcharging caused by the drive motor and the range extender charging the battery pack together.

Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these specific embodiments are only for illustration, and those skilled in the art can make the above-mentioned Various omissions, substitutions, and changes were made in the details of the methods and systems. For example, it is within the scope of the present invention to combine the above method steps so as to perform substantially the same function in substantially the same way to achieve substantially the same result. Accordingly, the scope of the invention is limited only by the appended claims.

Claims (6)

1. stroke-increasing electric automobile control method is characterized in that: comprise the following steps:

Entire car controller gathers from the chaufeur key position, pedal position, and gear, ancillary system demand button signal, the charging and discharging currents information that battery current electric quantity SOC and battery allow judges whether that needs start the mode of operation of distance increasing unit and distance increasing unit:

If meet: battery SOC＜30% or air-conditioning request be 1 or the warm braw request be 1 or battery SOC＜90% and acceleration pedal aperture 80%, after satisfying condition, distance increasing unit starts request and puts 1; And satisfy condition two: the key door position is positioned at On gear and accelerator pedal position〉2%, the distance increasing unit turn-off request sets to 0; Meet above two conditions, distance increasing unit enters start-up mode;

After entering start-up mode 50ms, judge that engine speed, whether greater than 800rpm, enters the distance increasing unit mode of operation after satisfying condition;

If meet: 30%＜SOC＜=90% and acceleration pedal aperture〉80% enter distance increasing unit and accelerate master mode; Withdraw from distance increasing unit acceleration master mode if meet 30%＜SOC＜=90% and acceleration pedal aperture＜50%;

If meet: SOC＜=30% and the statistics speed of a motor vehicle＜demarcation speed of a motor vehicle 1 enter distance increasing unit the first generating working point control pattern;

If meet: SOC＜=30% and the statistics speed of a motor vehicle〉demarcate the speed of a motor vehicle 2 and enter distance increasing unit the second generating working point control pattern;

If meet: SOC〉45% and the air-conditioning request be 1, enter distance increasing unit idling work point two;

If meet: SOC〉45% and the warm braw request be 1, enter distance increasing unit idling work point one;

If meet: SOC〉45% and the warm braw request be 0 and the air-conditioning request be 0 and acceleration pedal＜80% or satisfy condition two: the key door position is positioned at Acc gear and accelerator pedal position＜2 and generator speed＜1, the distance increasing unit turn-off request puts 1, enters the distance increasing unit shutdown mode;

If meet: detect the electrical generator life signal and be 0 and enter the distance increasing unit " shut " mode".

2. a kind of stroke-increasing electric automobile control method according to claim 1, it is characterized in that: at first entire car controller judges driving intention and distance increasing unit state, according to gear signal and the pedal signal of chaufeur, judges the pattern that distance increasing unit should be worked: distance increasing unit is closed, distance increasing unit starts, distance increasing unit generating operation point one, distance increasing unit generating operation point two, distance increasing unit idling work point one, distance increasing unit idling work point two, distance increasing unit acceleration power-assisted point, distance increasing unit shutdown; After the operating mode judgement was completed, the distance increasing unit controller carried out the coordination control of driving engine and electrical generator according to the mode instruction of entire car controller.

3. a kind of stroke-increasing electric automobile control method according to claim 2, it is characterized in that: described distance increasing unit starts master mode and is: electrical generator is operated in the electrical speed master mode, with the 800rpm start the engine, detect generator speed greater than 750rpm, send the engine ignition switch signal, detect engine speed greater than 850rpm and less than 1450rpm, electrical generator enters with turning master mode.

4. a kind of stroke-increasing electric automobile control method as claimed in claim 2; it is characterized in that: the shutdown master mode of described distance increasing unit is: sending the electrical generator rotating speed of target is 0; detect generator speed lower than 800rpm; the ignition lock signal kills engine; detect generator speed lower than 5rpm; close electrical generator high pressure control relay, close the electrical generator low-voltage relay after 50ms.

5. a kind of stroke-increasing electric automobile control method as claimed in claim 2 is characterized in that: the permanent power Generation Control of described distance increasing unit pattern is: engine operation is at the torque close-loop control mode, and electrical generator is operated in the rotating speed mode, according to the electrical generator operation point of demarcating, the rotating speed of target of corresponding electrical generator, the target operation torque of driving engine, reach power balance, the distance increasing unit controller is according to the open loop Throttle Position of having demarcated, it is poor that the actual torque that gathers the electrical generator feedback is done as closed loop control reference value and target torque, carry out the correction of open loop Throttle Position, electrical generator always works in rotating speed control mode, the distance increasing unit controller sends rotating speed of target to engine controller according to rotating speed of target with the gradient of 1000rpm/s, wherein the acceleration master mode of distance increasing unit also is in a kind of of permanent power Generation Control, generated output is different from permanent power operation point one and work two, in case distance increasing unit has been in permanent power generating operation point one or two, can not accelerate mode of operation controls.

6. a kind of stroke-increasing electric automobile control method as claimed in claim 2, it is characterized in that: described distance increasing unit idling work pattern: meet refrigeration and the demand for heat of chaufeur to the crew module, carry out DRIVEN BY AIR CONDITIONING COMPRESSOR and the idling warming-up provides warm braw, in this two operation point, engine operation is in the rotating speed mode, electrical generator is in turning state, for electrokinetic cell and drive motor, does not provide electric power.

Images