CN201003577Y - Drive system of hybrid electric vehicle - Google Patents

Abstract

The utility model discloses a driving system of a hybrid car, comprising a gas engine, a motor, a moment distributing mechanism, a gear box and a main oil pump. The moment distributing mechanism is a planet gear mechanism comprising a sun wheel, a planet rack and a gear ring; the planet rack is connected with the outputting axis of the gas engine; the sun wheel is connected with the rotor of the motor; the gear ring and the main oil pump are both connected with the inputting axis of the gear box. The utility model utilizes a planet gear mechanism as the moment distributing mechanism of the hybrid car; the motor and the gas engine are respectively connected with the sun wheel, the planet rack and the gear ring of the planet gear; thus the motor and the gas engine are coupled together; the powers of the motor and the gas engine are combined together to be input into the gear box; as adopting the planet gear mechanism, the utility has a more compact structure.

Description

Drive system of hybrid electric vehicle

technical field

The utility model relates to a driving system for a hybrid electric vehicle. The system drives the vehicle by using a combination of an internal combustion engine, a motor/generator, a moment meshing device, a gearbox and an electronically controlled clutch.

Background technique

So far, there have been a variety of hybrid solutions, and each solution has its own specific advantages and disadvantages. In most of the schemes, the hybrid system has a complex structure and high cost, or it only shows certain advantages compared with the traditional drive system under specific working conditions. In normal road driving, the advantages of hybrid drive are very limited.

Among these hybrid drive concepts, automatic and automated manual transmissions are already used. For example, patent DE 10036 966 A1 proposes the structure of a hybrid drive system with a planetary gearbox shifting device, a gearbox and a clutch to couple an electric motor and an internal combustion engine. Furthermore, patent DE 100 49 514 A1 also proposes a hybrid drive system with an electric motor and a combustion engine. In the planetary gearbox, two drive clutches and a brake clutch are integrated, through which the electric motor and the internal combustion engine can be connected as one.

Utility model content

The technical problem to be solved by the utility model is to provide a hybrid driving system with a more compact structure.

In order to solve the above-mentioned first technical problem, the utility model adopts the following technical scheme: a driving system of a hybrid electric vehicle, including an internal combustion engine, a motor, a torque distribution mechanism, a gearbox and a main oil pump, and the described torque distribution mechanism is a The planetary gear mechanism of the sun gear, the planet carrier and the ring gear, the planet carrier is connected with the output shaft of the internal combustion engine; the sun gear is connected with the rotor of the motor; the ring gear and the main oil pump are connected with the input shaft of the gearbox connected.

The utility model utilizes a planetary gear mechanism as the torque distribution mechanism of the hybrid electric vehicle, and the motor, the internal combustion engine and the gearbox are respectively connected with the sun gear, the planet carrier and the ring gear of the planetary gear, so that the motor and the internal combustion engine are coupled together, and After the power is synthesized, it is input into the gearbox. Because of the planetary gear mechanism, the structure is more compact.

As a preferred solution of the above technical solution: the torque distribution mechanism is a planetary gear mechanism provided with double-row planetary gears, and the planet carrier is connected to the double-row planetary gears at the same time. When the torque distribution mechanism composed of planetary gear devices is used, in order to improve the power and control convenience of the vehicle drive system, it is usually required that the speed ratio of the motor and the engine is close to -1 when the speed of the gearbox input shaft is 0. If a single-row planetary gear is used, in order to realize the coupling output of the motor output torque and the engine output torque to the input shaft of the gearbox, the gearbox is usually connected to the planet carrier, the motor is connected to the ring gear, and the engine is connected to the sun gear. When the speed of the input shaft of the gearbox is 0, in order to achieve the speed ratio of the motor and the engine close to -1, the gear ratio of the ring gear and the sun gear should be close to 1. In other words, in order to arrange the lower planetary gear, the sun gear needs to be enlarged The diameter is several times, and then the size of the entire torque distribution mechanism is increased several times; and for the torque distribution mechanism of the double-row planetary gear, the gearbox can be connected to the ring gear, and the motor and the engine are respectively connected to the sun gear and the planets. On the frame, when the speed of the gearbox input shaft is 0, the speed ratio of the motor to the engine is close to 1, and the gear ratio of the ring gear to the sun gear of the double-row planetary gear device is close to 2. In this case, the diameter of the sun gear Much smaller, the size of the entire torque distribution mechanism is also much smaller, so that the structure of the drive system is also more compact.

As a preferred solution of the above technical solution: a fixedly installed internal combustion engine brake is also included, and the internal combustion engine brake is connected with the output shaft of the internal combustion engine. When the hybrid vehicle is operating in pure electric mode, the internal combustion engine brake can be used to lock the flywheel and prevent the internal combustion engine from turning. Since the flywheel brake can be fixedly installed in the engine room of the internal combustion engine, it is beneficial to the space arrangement of the drive system, does not increase the axial dimension of the drive system, and is also convenient for disassembly and maintenance.

As an improvement to the above technical solution, an electronically controlled clutch is also provided between the sun gear and the planetary carrier of the torque distribution mechanism. When the electronically controlled clutch is engaged, the sun gear and the planet carrier are locked as a whole, and the transmission ratio of the torque distribution mechanism is 1. At this time, the motor can work in the electric state or in the power generation state. The internal combustion engine and the electric motor can be controlled according to the control requirements. Arbitrary distribution of output torque.

As a further optimization of the above improvement scheme: an electronically controlled oil pump is also connected in parallel with the main oil pump. In the start-stop mode or other working modes, the main oil pump may not be able to maintain the oil pressure of the hydraulic system. In order to prevent the oil pressure of the hydraulic system from being insufficient, an electronically controlled oil pump is integrated to ensure the normal oil pressure of the hydraulic system and the electronically controlled clutch. normal work.

As a preferred solution of the above technical solution: the motor is a four-quadrant motor that can work in a motoring state or a generating state in both forward and reverse directions. That is, when the motor is running forward, the motor can work in the motoring state or the generating state; when it is rotating negatively, it can also work in the motoring state or the generating state. According to different gears and different driving conditions, the electric motor can be used to start the internal combustion engine in different ways. Therefore, the internal combustion engine does not need to be equipped with a starter motor in this hybrid power system.

As a preferred solution of the above technical solution: a torsional vibration damper is also connected between the output shaft of the internal combustion engine and the planet carrier. Vibration generated in the drive system can be reduced.

As a preferred solution of the above technical solution: the gearbox is provided with a clutch for locking or releasing the input shaft of the gearbox. When the clutch is engaged, the speed of the input shaft of the transmission can be 0, so as to facilitate the realization of control requirements.

Description of drawings

The utility model is described in further detail below in conjunction with accompanying drawing and specific embodiment.

Fig. 1 is a structural schematic diagram of a driving system of a hybrid electric vehicle of the present invention.

Figure 2 describes the relationship between the rotational speed and torque of each component in step 1 of the cold start process.

Figure 3 describes the relationship between the rotational speed and torque of each component in the second step of the cold start process.

Figure 4 describes the relationship between the rotational speed and torque of each component in step 3 of the cold start process.

Figure 5 describes the relationship between the speed and torque of each component in the hot start mode.

Figure 6 describes the relationship between the speed and torque of each component in the parallel starting mode.

Figure 7 describes the relationship between the rotational speed and torque of each component from the planetary gear starting mode to step 1 of the parallel mode.

Figure 8 describes the relationship between the rotational speed and torque of each component from the planetary gear starting mode to step 2 of the parallel mode.

Figure 9 describes the relationship between the rotational speed and torque of each component in the parallel power assist mode.

Figure 10 describes the relationship between the speed and torque of each component in the parallel power generation mode.

Figure 11 describes the relationship between the speed and torque of each component in the parallel braking mode.

Figure 12 describes the relationship between the rotational speed and torque of each component in low-speed driving mode 1 (motor assist).

Figure 13 describes the relationship between the speed and torque of each component in low-speed driving mode 2 (electrical motor power generation).

Figure 14 describes the relationship between the rotational speed and torque of each component during pure electric drive.

Figure 15 describes the relationship between the speed and torque of each component from pure electric mode to parallel mode.

Among them, the meanings of the following symbols in Figure 2-Figure 15 are:

被驱动

提供驱动力矩保持同样状态

driven

Provide driving torque and maintain the same state

目标转速状态----初始转速状态

Target speed state----initial speed state

Detailed ways

As shown in Figure 1, the drive system of a kind of hybrid electric vehicle of the present utility model comprises internal combustion engine 1, motor 9, torque distribution mechanism 7, gearbox 14 and main oil pump 17, and internal combustion engine 1 can be gasoline engine and also can be diesel engine; Motor 9 It is a four-quadrant motor, that is, it can work in a motoring state or a generating state when it is forward or reverse, and it includes a rotor 8 and a stator 10, wherein the stator 10 is installed on a fixed casing 11. The torque distribution mechanism 7 is a planetary gear mechanism, which includes a sun gear 7s, a planetary carrier 7c and a ring gear 7r, and a double row of planetary gears is arranged between the sun gear 7s and the ring gear 7r, and the planetary carrier 7c and the two rows of planetary gears simultaneously The planet carrier 7c is connected to the output shaft 2 of the internal combustion engine 1 through a torsional vibration damper 5; the sun gear 7s is connected to the rotor 8 of the motor 9; the ring gear 7r and the main oil pump 17 are connected to the input shaft of the gearbox 14 18, in this embodiment, the gearbox 14 is an automatic gearbox, installed in a casing 13, wherein a clutch (not shown) for locking or releasing the gearbox input shaft 18 is also provided, and the transmission The box 14 has an output shaft 15 . The internal combustion engine brake 4 is installed and fixed on the internal combustion engine casing, and is used to lock the flywheel 3 on the output shaft 2 of the internal combustion engine. An electronically controlled clutch 6 is also provided between the sun gear 7s and the planet carrier 7c of the torque distribution mechanism 7 for locking the sun gear 7s and the planet carrier 7c. In order to prevent the oil pressure of the hydraulic system from being insufficient in some cases, this embodiment also integrates an electronically controlled oil pump 16 connected in parallel with the main oil pump 17 to ensure the normal oil pressure of the hydraulic system and the normal operation of the electronically controlled clutch 6 . The hybrid vehicle controller 19 is used for intelligently controlling the vehicle.

The different working modes and operation methods of the drive system of the above-mentioned hybrid electric vehicle will be described below. cold start mode

When the ambient temperature is low, such as when the water temperature and gearbox oil temperature are low, the electronically controlled oil pump 16 cannot build up enough pressure to engage the electronically controlled clutch 6. Forward rotation drive drives the gearbox input shaft 18 to rotate forward, so that the main oil pump 17 installed on the gearbox input shaft 18 is forwardly driven to build up sufficient pressure. The working state at this time is shown in Figure 2; ② When the oil pressure is sufficient to engage the electronically controlled clutch 6, the hybrid vehicle controller 19 controls the engagement of the electronically controlled clutch 6, and drags the internal combustion engine 1 to a preset speed. As shown in Figure 3; ③Then the internal combustion engine 1 is injected and ignited, and kept at the preset idle speed, the motor 9 works at a negative speed, so that the input shaft 18 of the gearbox is kept at zero speed, ready to start, and its working state As shown in Figure 4.

In the P and N gears, when the driver does not need to start the whole vehicle, after starting the internal combustion engine, the system can perform warm-up work. hot start mode

When the internal combustion engine is warming up and the gears are in R and D gears, the internal combustion engine will stop working after parking. If you stop in front of a red light, the green light will turn on immediately. At this time, you need to quickly start the internal combustion engine. This system can adopt lever start mode. That is, the clutch in the automatic gearbox 14 is used to lock the input shaft 18 of the gearbox, the motor 9 reverses and drives the internal combustion engine to a preset speed value, and then the internal combustion engine injects fuel and ignites. The rotational speed movement relation of its start-up process is shown in Fig. 5 .

When the internal combustion engine is warming up and the gears are in P and N gears, if you need to start the internal combustion engine to charge the battery, you can use the parallel start mode. Its operation steps are as follows, first close the electronically controlled clutch 6, and then the motor 9 starts to drive the internal combustion engine to a preset speed from a standstill. Immediately, the internal combustion engine is injected and ignited, and the rotational speed movement relationship in the starting process is shown in Figure 6.

In a conventional car with an automatic transmission, when the brake pedal is pressed in D, the car stops, but the internal combustion engine is still idling. The vehicle with the hybrid power system of the utility model uses the above-mentioned operation method. When the brake pedal is stepped on at the D gear, the car stops, and the internal combustion engine can also stop running. , the whole vehicle can quickly drive the internal combustion engine from a standstill to the target speed, and then the internal combustion engine is injected and ignited, and combined with the control of the motor, it can start quickly. Realized the control function of start/stop mode. Since the internal combustion engine is in a shutdown state when the car is stopped, fuel consumption can also be reduced. Planetary gear start mode

When starting, utilize the physical characteristics of the torque distribution mechanism 7, that is, its output torque is the sum of the output torques of the internal combustion engine 1 and the motor 9, to meet the large starting torque required by the hybrid vehicle. ①Firstly, the starting working speed of the internal combustion engine is preset, and then, the output torque of the motor 9 is controlled to continuously increase the speed of the input shaft 18 of the gearbox, so that the motor gradually changes from reverse rotation to forward rotation. As shown in Figure 7, the speed relationship is from The dotted line gradually transitions to the solid line; ② When the speeds of the internal combustion engine 1 and the motor 9 tend to be the same, engage the electronically controlled clutch 6 and enter the parallel mode, as shown in Figure 8 .

parallel mode

In the parallel mode, after the electronically controlled clutch 6 is engaged, the motor 9 can be operated in a motor state or a generator state as required. When the driver's demand torque is large, the motor 9 works in the motor state to provide power assistance, and its speed-torque relationship is shown in Figure 9; when the battery SOC is low, the motor 9 works in the power generation state to generate power, and its speed-torque relationship is shown in Figure 10 shown. When braking in parallel mode, the internal combustion engine 1 does not inject fuel, and the motor 9 works in the state of generating electricity to generate electricity. At the same time, the braking system of the whole vehicle is working. The relationship between its speed and torque is shown in Figure 11.

low drive mode

When the speed of the vehicle was reduced, the system entered into the planetary gear starting mode from the parallel mode again, and at this moment the electronically controlled clutch 6 was released. The system will enter different low-speed driving modes according to the SOC of the battery and the needs of the driver. When the battery SOC is in the normal range, the motor 9 works in the motor state, as shown in FIG. 12 . When the SOC of the battery is lower than the normal value and needs to be charged, the motor 9 is driven to rotate in the direction of negative rotation speed and works as a generator, as shown in FIG. 13 .

pure electric mode

When the drive torque demanded by the system is low, the hybrid power enters the pure electric drive mode, the flywheel brake 4 of the internal combustion engine is engaged, and the motor 9 works in the motor state to drive the whole vehicle to run. The speed relationship is shown in Figure 14.

Running in the pure electric mode, when the system requires a larger drive torque, the hybrid vehicle switches to the parallel mode, and the relationship of the speed change process is shown in Figure 15. The operation process of switching from pure electric mode to parallel mode: first loosen the flywheel brake 4 of the internal combustion engine, and engage the electronically controlled clutch 6 at the same time. When the internal combustion engine speed reaches the pre-selected speed, the internal combustion engine will inject fuel to ignite, and the inertia of the motor can be used energy to maximize the starting of the internal combustion engine under no-load conditions.

Claims (8)

1. the drive system of a hybrid vehicle, comprise internal-combustion engine (1), motor (9), moment distributing mechanism (7), gearbox (14) and main oil pump (17), it is characterized in that: described moment distributing mechanism (7) is a planetary gears that comprises sun gear (7s), planet carrier (7c) and gear ring (7r), and described planet carrier (7c) is connected with the output shaft (2) of internal-combustion engine; Described sun gear (7s) is connected with the rotor (8) of motor; Described gear ring (7r), main oil pump (17) all are connected with the input shaft (18) of gearbox.

2. the drive system of hybrid vehicle according to claim 1, it is characterized in that: described moment distributing mechanism (7) is a planetary gears that is provided with double planet wheel, and described planet carrier (7c) is connected simultaneously with double planet wheel.

3. the drive system of hybrid vehicle according to claim 1 is characterized in that: also comprise a hard-wired internal-combustion engine braking device (4), described internal-combustion engine braking device (4) is connected with the output shaft (2) of internal-combustion engine.

4. according to the drive system of claim 1 or 2 or 3 described hybrid vehicles, it is characterized in that: also be provided with electric control clutch (6) between the sun gear (7s) of described moment distributing mechanism (7) and the planet carrier (7c).

5. the drive system of hybrid vehicle according to claim 4 is characterized in that: comprise that also an automatically controlled oil pump (16) is in parallel with main oil pump (17).

6. the drive system of hybrid vehicle according to claim 1 is characterized in that: described motor (9) is for being operated in the four-quadrant motor of motoring condition or generating state when forward and backward.

7. the drive system of hybrid vehicle according to claim 1 is characterized in that: also be connected with a torsional balancer (5) between output shaft of described internal-combustion engine (2) and the planet carrier (7c).

8. the drive system of hybrid vehicle according to claim 1 is characterized in that: be provided with a clutch that is used for pinning or discharging gearbox input shaft (18) in the described gearbox (14).

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