CN101327728A - Bus hybrid drive system - Google Patents

Abstract

The invention discloses a hybrid power drive system for buses in the technical field of vehicle engineering, wherein: the engine is connected coaxially with an integrated starter generator, the integrated starter generator is connected with an automatic clutch driving disc, and the automatic clutch is connected through a drive motor and a reduction mechanism. The reduction mechanism is respectively connected with the driving motor and the main reducer-differential, the main reducer-differential is connected with the wheels through the drive axle, the power battery pack is connected with the motor controller through the cable, and the motor controller is connected with the integrated starter through the cable. The generator and drive motor are connected. The invention maintains the structure of the traditional vehicle to the greatest extent, and optimizes the working point of the engine by using dual motors, so that the engine can run stably in a high-efficiency and low-emission area, and is especially suitable for urban low-speed bus operation.

Description

Bus hybrid drive system

technical field

The invention relates to a drive system in the technical field of vehicle engineering, in particular to a hybrid drive system for a bus with an integrated starter generator.

Background technique

With the tension of world energy and the strengthening of human environmental awareness, safety, energy saving and environmental protection have become the themes of today's automobile development. As one of the new energy vehicles, hybrid vehicles can better solve the above problems. A hybrid vehicle is a vehicle that is jointly driven by an engine and an electric motor system. The engine can be an internal combustion engine using multiple fuels; the motor can be either a permanent magnet motor or an excitation motor, a synchronous motor or an asynchronous motor. The clutch can be a manual clutch or an electronically controlled automatic clutch. For hybrid vehicles with manual gearbox and manual clutch, since the engine is directly connected to the drive shaft through the clutch and gearbox, the vehicle cannot realize pure electric drive mode and series drive mode. Under public transport conditions), it is impossible to optimize the minimization of fuel consumption. Moreover, in pure electric driving conditions, traditional air conditioning, steering and braking devices will not work due to lack of power.

After searching the literature of the prior art, it was found that the patent 200610137881.7 discloses a series hybrid electric vehicle power distribution comprehensive control system, which is suitable for the motor motion control of the series hybrid electric vehicle and the energy management of the multi-energy powertrain. It can realize the distribution and management of the energy flow of the series hybrid vehicle, and realize the coordinated control of the independent drive of the double-sided motors, but the application range is limited to the series type. U.S. Patent US 2004/0147365 A1 and CN200310119680.0 disclose a hybrid power structure using dual motors before and after the gearbox. Electric drive function.

Contents of the invention

The purpose of the present invention is to address the deficiencies of the prior art, to provide a hybrid drive system for buses, which has better economy and lower emissions than traditional vehicles, can be driven by two different power sources, and can realize braking A hybrid drive system that recovers energy while improving engine efficiency. The system is mainly driven by electric motors, which can expand the mileage of hybrid vehicles through generator sets, and achieve the purpose of saving fuel and ensuring the power performance of the whole vehicle on the basis of saving manufacturing and transformation costs to the greatest extent. Inadequacies of the device in terms of auxiliary transmission and shifting, etc.

The present invention is achieved through the following technical solutions:

The bus hybrid drive system involved in the present invention includes: wheels, final reducer-differential, drive motor, reduction mechanism, automatic clutch, integrated starter generator (abbreviated as ISG), engine, motor controller, power battery Group, in which: the engine is connected coaxially with the integrated starter generator, the integrated starter generator is connected with the active disc of the automatic clutch, the automatic clutch is connected through the drive motor and the reduction mechanism, and the reduction mechanism is respectively connected with the drive motor and the final reducer-differential , the final reducer-differential is connected to the wheels through the drive axle, the power battery pack is connected to the motor controller through cables, and the motor controller is connected to the integrated starter generator and drive motor through cables.

The motor controller includes a drive motor controller and an integrated starter-generator controller, which are used to control the drive motor and the integrated starter-generator respectively.

The combination of the drive motor and the reduction mechanism constitutes an electromechanical coupling mechanism.

The present invention only adds an automatic clutch on the basis of the series hybrid power, which has the advantages of the series hybrid power and reduces the power of the generator and the driving motor at the same time; the system structure is simple, avoiding the complex transmission system, and the automatic clutch is relatively mature. And the control requirement is low.

The structural innovation of the present invention lies in the coupling of the drive motor and the deceleration mechanism, and the deceleration mechanism is used as the transmission part between the drive motor and the final reducer-differential joint mechanism, which greatly reduces the installation space. The deceleration mechanism has the advantages of compact structure, large transmission ratio, large bearing capacity, stable transmission and high transmission efficiency. The deceleration mechanism here is used in conjunction with the integrated starter generator, automatic clutch and drive motor in the transmission system to realize partial The purpose of power splitting and deceleration is to achieve good matching and optimal control among the hybrid vehicle engine, electric motor, and power battery pack.

In the present invention, a two-speed speed change mechanism can also be set between the electromechanical coupling mechanism and the final drive-differential joint mechanism. The existence of the two-speed speed change mechanism expands the speed change range, reduces the requirements for the speed range of the driving motor, and makes the speed change Control is more flexible.

The present invention includes the following multiple driving modes:

(1) Pure electric drive mode: When the vehicle is started or the vehicle is working with a low load and the SOC value of the battery is not low, the drive motor works alone, and the battery provides electric energy for the drive motor. The electric energy of the battery is used to drive the car, the engine and ISG are not involved in the work, and it is only driven by the drive motor;

(2) Series working mode: When the vehicle starts or the vehicle is under low load and the SOC value of the battery is low, the ISG starts the engine first, the clutch is disconnected, the engine generates electricity, and the drive motor drives the vehicle. The serial working mode generally works in the following situations:

a. Low-speed range, high-power driving conditions, such as continuous climbing, etc.;

b. The power of the battery is lower than the preset value, and it is necessary to replenish the power of the battery in time

(3) Parallel driving mode: When the vehicle demand power is greater than the engine efficiency optimization power and the battery SOC value is not low, the engine, drive motor and integrated starter generator jointly drive the vehicle after the clutch is engaged. This mode usually works in the middle and low speed acceleration and high speed areas;

(4) Engine alone drive mode: When the vehicle power demand is in the engine efficiency optimization area or the battery does not have enough power to supply the motor to work, the engine drives the vehicle alone, and the drive motor and integrated starter generator do not work;

(5) Engine driving driving power generation mode: When the vehicle is running, if the vehicle demand power is less than the engine efficiency optimization power and the battery SOC value is low, the engine will drive the vehicle, and the drive motor will work as a generator to absorb energy to the battery to adjust the engine power. Working efficiency and battery supplementary power, this mode generally works in the medium speed area (the engine power load is low and the efficiency is low);

(6) Brake power generation mode: When decelerating or coasting, the drive motor acts as a generator to absorb vehicle kinetic energy to the battery.

Compared with the existing hybrid hybrid vehicles, the present invention has the following remarkable effects: it can realize functions such as automatic start and stop of the engine, electric power assist and high-efficiency and high-power electric energy output, and at the same time, the engine and the integrated starter generator constitute a highly efficient vehicle-mounted The generator set keeps the engine always working at an optimal operating point with low fuel consumption and low emission or shuts down under low-speed following conditions of the vehicle (such as urban bus conditions), and the driving power of the whole vehicle is provided by a high-power drive motor. In high-speed driving conditions, the engine, drive motor and wheels are mechanically connected, and the power of the two can be transmitted to the wheels through the transmission system. The vehicle controller can determine the vehicle's state of charge according to the driver's behavior and the battery SOC (State Of Charge) value. Energy distribution to enable drive modes other than pure electric and series drive. This solution uses a large number of power systems of traditional cars, which can greatly reduce manufacturing costs.

The invention achieves the purpose of power splitting and deceleration, and further realizes good matching and optimal control among the engine, electric motor and power battery pack, reduces the use cost of the vehicle, reduces fuel costs, and reduces the impact on the petrochemical industry. Fuel dependence, reduced emissions of greenhouse gases and various harmful gases, while improving the efficiency of power grid generators. Adding a two-speed transmission mechanism not only expands the transmission range, but also reduces the requirements for the speed range of the drive motor, making the transmission control more flexible.

Description of drawings

Fig. 1 is a structural schematic diagram of Embodiment 1 of the present invention;

Fig. 2 is a schematic structural diagram of Embodiment 2 of the present invention.

Detailed ways

The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings: this embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following the described embodiment.

Embodiment one

As shown in Figure 1, the drive system of this embodiment includes an engine 1, an integrated starter generator 2, an automatic clutch 3, an electromechanical coupling mechanism 4, wheels 5, a final drive-differential 6, a motor controller 7, and a power battery Group 8, wherein: the electromechanical coupling mechanism 4 is composed of a drive motor and a reduction mechanism, the engine 1 and the integrated starter generator 2 are coaxially connected, the integrated starter generator 2 is connected to the driving disc of the automatic clutch 3, and the automatic clutch 3 is connected through the electromechanical coupling mechanism The drive motor in 4 is connected to the reduction mechanism, the reduction mechanism is respectively connected to the drive motor and the final reducer-differential 6, the final reducer-differential 6 is connected to the wheel 5 through the drive axle, and the power battery pack 8 is connected to the The motor controller 7 is connected, and the motor controller 7 is respectively connected with the drive motor in the integrated starter generator 2 and the electromechanical coupling mechanism 4 through cables.

The motor controller 7 includes a drive motor controller and an integrated starter generator motor controller.

The power battery pack 8 contains a battery management system.

The engine 1 is used as a power unit, and its power can be directly transmitted to the wheels 5 through a mechanical system, or it can charge the power battery pack 8 in the form of electric energy through the integration of the starter generator 2 and the motor controller 7, or provide it to the electromechanical coupling mechanism 4. drive motor.

The integrated starter generator 2 is mainly used to use the electric energy of the power battery pack 8 to start the engine 1 and absorb the energy of the engine 1 to generate electricity. The driving motor in the electromechanical coupling mechanism 4 is used to drive the wheels 5 and recover the kinetic energy when the vehicle brakes.

The reduction mechanism in the electromechanical coupling mechanism 4 is used as the transmission part between the drive motor and the final reducer-differential 7, and is used in conjunction with the integrated starter generator 2, automatic clutch 3 and drive motor in the transmission system to simultaneously realize power The purpose of shunting and deceleration, and then can achieve a good match and optimal control among the hybrid vehicle engine, electric motor, and power battery pack.

The working process introduction under the various modes of the above-mentioned embodiment:

In the pure electric driving mode, the engine 1 is stopped, and the power battery pack 8 provides energy to the drive motor in the electromechanical coupling mechanism 4, and the output energy of the drive motor is transmitted to the wheels 5 through the reduction mechanism and the final drive-differential 6 in sequence. Among them, the electric energy of the power battery pack 8 has two sources: direct supply from the engine; feedback supply from braking energy.

In the series drive mode, the output energy of the engine 1 is charged to the power battery pack 8 through the power generation of the integrated starter generator 2 or is directly provided to the drive motor in the electromechanical coupling mechanism 4 without passing through the power battery pack 8 . The energy is supplied to the drive motor in the electromechanical coupling mechanism 4 , and the energy output from the drive motor is transmitted to the wheels 5 through the reduction mechanism and the final reducer-differential 6 in sequence.

In the parallel driving mode, the first energy transmission path is: the energy output by the engine 1 passes through the reduction mechanism in the integrated starter generator 2, the clutch 3 and the electromechanical coupling mechanism 4; the second energy transmission path is: the battery pack 8 to the motor control 7, and then to the drive motor in the electromechanical coupling mechanism 4. After the two strands of energy are coupled through the reduction mechanism in the electromechanical coupling mechanism 4 , they are then transmitted to the wheels 5 through the final reducer-differential 6 .

In the engine-only driving mode, the energy output by the engine 1 is transmitted to the wheels 5 through the integrated starter generator 2 , the clutch 3 , and the final drive-differential 6 in sequence. During this process, the rotor of the driving motor in the integrated starter generator 2 and the electromechanical coupling mechanism 4 is idling, and both do not perform work.

Driven by the engine, in the power generation mode of the driving motor, the energy from the engine 1 passes through the integrated starter generator 2 and the driven plate of the clutch 3, and then is divided into two paths, which are respectively charged by the motor controller 7 to the power battery pack 8 and passed through the final reducer-differential Transmission 6 to wheels 5.

In the braking energy feedback mode, the vehicle kinetic energy from the wheels 5 charges the power battery pack 8 through the drive axle, the differential-final drive 6 , the reduction mechanism in the electromechanical coupling mechanism 4 , the driving motor, and the motor controller 7 .

Embodiment two

As shown in Figure 2, this embodiment is an optimized solution, and on the basis of Embodiment 1, it also includes a two-speed transmission 9, and the two-speed transmission 9 is arranged between the electromechanical coupling mechanism 4 and the final drive-differential 6 combined mechanism Between, the input shaft of the two-speed transmission 9 is connected with the reduction mechanism in the electromechanical coupling mechanism 4, and the output shaft of the two-speed transmission 9 is connected with the final drive-differential 7. Other component connections, working modes, and basic control strategies are the same as those in Embodiment 1, and will not be repeated here.

In this embodiment, due to the existence of the two-speed transmission mechanism, the speed change range is enlarged, and the requirement on the speed range of the driving motor is reduced, so that the speed change control is more flexible.

Claims (3)

1. A bus hybrid drive system, comprising: wheels, final drive-differential, reduction mechanism, drive motor, automatic clutch, integrated starter generator, engine, motor controller, power battery pack, characterized in that : The engine is coaxially connected with the integrated starter generator, the integrated starter generator is connected with the active disc of the automatic clutch, the automatic clutch is connected with the reduction mechanism through the drive motor, the reduction mechanism is respectively connected with the drive motor and the main reducer-differential, and the main reducer The gear-differential is connected to the wheels through the drive axle, the power battery pack is connected to the motor controller through cables, and the motor controller is connected to the integrated starter generator and the drive motor through cables. 2. The bus hybrid drive system according to claim 1, characterized in that, a two-speed transmission is arranged between the speed reduction mechanism and the final drive-differential, and the input shaft of the two-speed transmission is connected with the speed reduction mechanism, The output shaft is connected with the final drive-differential. 3. The bus hybrid drive system according to claim 1, characterized in that, the engine is used as a power unit, and its power is directly transmitted to the wheels through a mechanical system, or through an integrated starter generator and a motor controller with electric energy way to charge the power battery pack, or provide it to the drive motor.

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