CN112124065A

CN112124065A - Vehicle hybrid power transmission system

Info

Publication number: CN112124065A
Application number: CN202011121630.6A
Authority: CN
Inventors: 花潍
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2020-12-25

Abstract

The invention discloses a vehicle hybrid power transmission system, which relates to the technical field of new energy of automobiles.A main body of the vehicle hybrid power transmission system is provided with an input member, wherein the input member is provided with a planetary gear set and wheels, the wheels and the planetary gear set are respectively provided with two groups, the two groups of planetary gear sets are respectively connected to the two wheels, the independent driving control of the planetary gear set to the wheels is realized, and the differential speed driving process of the two wheels can be realized without installing a differential mechanism, so the related parts are relatively reduced, the production cost is relatively reduced, and the economic benefit is higher.

Description

Vehicle hybrid power transmission system

Technical Field

The invention relates to the technical field of new energy of automobiles, in particular to a hybrid power transmission system of a vehicle.

Background

In recent years, global alertness has been raised due to environmental problems such as global warming, glacier thawing, and sea level elevation caused by an increase in the emission of greenhouse gases such as carbon dioxide. In addition, the objective factors that the petroleum reserves in China are small and the crude oil highly depends on import are considered, so that the reduction of the consumption rate of gasoline and diesel oil of vehicles gradually draws the attention of China. At present, under the circumstances that a power battery and a fuel battery for a vehicle are restricted by key technologies, charging facilities are not popularized, and an electric vehicle is difficult to popularize comprehensively in a short time, a hybrid electric vehicle becomes a more suitable development route at present due to the mature technology of the hybrid electric vehicle.

At present, most of power transmission devices of hybrid electric vehicles in the market are connected with wheels through a transmission element, a speed regulation device, a differential mechanism and the like after power output of an engine or a motor, for example, the application publication number is CN107825954A, the power output by the engine and the motor is utilized to drive a double planetary gear to operate and finally output from an output shaft end, only one output shaft is arranged, and the output shaft can be connected to two wheels through the differential mechanism, so that the whole parts of the hybrid electric vehicle are more and complicated, and the cost is correspondingly increased.

Disclosure of Invention

In order to solve the above-mentioned problems, an object of the present invention is to provide a vehicle hybrid transmission system that realizes a differential speed running of a vehicle and that has a lighter overall system and higher economic efficiency.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a vehicle hybrid power transmission system is provided with an input member provided with two planetary gear sets and two wheels connected to the two wheels, respectively.

Through adopting above-mentioned technical scheme, connect two wheels respectively on two sets of planetary gear sets for this hybrid transmission system has two output shafts, can realize the individual drive to two wheels, need not to connect differential mechanism again and can realize the differential process of traveling of two wheels, consequently, required spare part reduces relatively, and its manufacturing cost can reduce.

Preferably, a first transmission member is provided between the planetary gear set and the wheel.

By adopting the technical scheme, the first transmission member realizes the connection between the planetary gear set and the wheel.

Preferably, planetary gear set includes sun gear, planet wheel and annular ring gear, the planet wheel cooperation sets up in the inner circle of annular ring gear, sun gear and planet wheel meshing, one side of planet wheel is connected with the planet carrier, the planet wheel rotates and connects in the planet carrier.

Through adopting above-mentioned technical scheme, sun gear and the planet wheel meshing among the planetary gear set, planet wheel and annular ring gear meshing, the planet carrier rotates with the planet wheel and is connected to realize the transmission of power and speed.

Preferably, the vehicle hybrid power transmission system is provided with an output member, the output member is provided with motor generator sets, the motor generator sets are provided with two sets, and the two sets of motor generator sets are respectively connected with the two sets of planetary gear sets.

By adopting the technical scheme, the electric driving of the planetary gear set is realized by utilizing the motor generator set in the output component, and the power generation process of the motor generator can also be realized by utilizing the motion of the planetary gear set.

Preferably, the motor generator set is connected with the annular gear ring in a matched mode.

Through adopting above-mentioned technical scheme, with motor generator set and annular ring gear cooperation for the effort and the speed of motor generator set output transmit the wheel behind annular ring gear and planet wheel, planet carrier, realize the variable speed function.

Preferably, the output member includes an engine, and a second transmission member is provided between the engine and the planetary gear set.

By adopting the technical scheme, the rotating speed output by the engine is transmitted to the planetary gear set through the second transmission component, and the engine driving process of the planetary gear set is realized.

Preferably, the second transmission member is connected to and acts on the sun gear of both sets of planetary gears.

By adopting the technical scheme, the arrangement of the second transmission component ensures that the sun gears in the two groups of planetary gear sets can keep synchronous motion, and the connection mode ensures that the whole structure of the system is more compact.

Preferably, the motor generator set is provided with a power module, and the power module is connected to the motor generator set through a connecting circuit.

Through adopting above-mentioned technical scheme, the setting of power module can realize motor generator set's charge-discharge.

Preferably, the main body is further provided with a stationary member connected to the input member and the output member.

By adopting the technical scheme, the static components connected with the input component and the output component can realize the supporting and limiting functions of the input component and the output component.

Preferably, the vehicle hybrid power transmission system is further provided with a controller connected to the output member through a connection circuit.

By adopting the technical scheme, the controller monitors the working state of the output component and realizes the conversion control of the power generation and the electric output state of the motor generator set.

Compared with the prior art, the invention has the advantages that: (1) the two groups of planetary gear sets are respectively connected with the two wheels, so that the two groups of planetary gear sets respectively drive the two wheels, the differential function of the two wheels can be realized without a differential mechanism, and the integral parts of the system are relatively reduced; (2) by utilizing a second transmission component between the engine and the planetary gear sets, and the second transmission component is connected with and acts on the sun gears in the two planetary gear sets, the engine can realize synchronous drive on the sun gears in the planetary gear sets; (3) the motor generator set is connected to the annular gear ring in the planetary gear set, so that the speed of the planetary gear set and the wheels is regulated, and the structure is compact.

Drawings

FIG. 1 is a schematic structural view of example 1;

FIG. 2 is a schematic view of the structure of the planetary gear set in embodiment 1.

In the figure: 1-a planetary gear set; 110-sun gear; 120-a planet wheel; 130-ring gear ring; 140-a planet carrier; 2-vehicle wheels; 3-a first transmission member; 4-a motor generator set; 5-an engine; 6-a second transmission member; and 7, a power supply module.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

Example 1

A hybrid drive train for a vehicle, as shown in fig. 1, includes an input member and an output member, wherein the output member provides a force to the drive train, and the input member is connected to the output member, and the output force of the output member is used to move the input member.

The vehicle hybrid power transmission system is also provided with a static component which is connected with the input component and the output component and realizes the supporting or limiting function for the input component and the output component.

In the present embodiment, the output member is provided with the engine 5, and the engine 5 is connected to the input member to realize the driving process of the engine 5.

The output member is provided with a motor generator set 4, and the motor generator set 4 is connected with the input member to realize an electric driving process. The motor generator set 4 is a common device integrating a motor and a generator in the market.

The input component comprises planetary gear sets 1 and wheels 2, wherein the planetary gear sets 1 and the wheels 2 are both provided with two groups, the two groups of planetary gear sets 1 are symmetrically arranged left and right, as shown in fig. 1, the two wheels 2 are symmetrically arranged on the outer sides of the two groups of planetary gear sets 1, and the two wheels 2 are respectively driven by the two groups of planetary gear sets 1 in an independent control mode.

The planetary gear set 1 is provided with a sun gear 110, planet gears 120 and an annular ring gear 130. The sun gear 110 is engaged with the planet gears 120, the planet gears 120 are arranged in an inner ring of the annular ring gear 130 in a matching way, the sun gear 110, the planet gears 120 and the annular ring gear 130 are in a position relation as shown in fig. 1 and fig. 2, a planet carrier 140 is arranged outside the planet gears 120, and the planet gears 120 are rotatably connected to the planet carrier 140 through bearings. When the sun gear 110 rotates, the planet gear 120 revolves around the sun gear 110 and rotates around itself, and drives the planet carrier 140 connected with the planet gear to rotate around the sun gear 110; in addition, when the ring gear 130 rotates, the planet gears 120 are also driven to rotate and revolve, so that the planet carrier 140 rotates, and a torque transmission process among the sun gear 110, the planet carrier 140 and the ring gear 130 can be realized.

A first transmission member 3 is provided between the planetary gear set 1 and the wheel 2, and the first transmission member 3 connects the planetary gear set 1 with the wheel 2. Specifically, the two ends of the first transmission member 3 are respectively connected with the planet carrier 140 and the wheel 2, and the first transmission member 3 realizes synchronous operation of the planet carrier 140 and the wheel 2, that is, the rotation speed (final output rotation speed) of the wheel 2 is the same as the rotation speed of the planet carrier 140.

In the present embodiment, a second transmission member 6 is provided between the engine 5 and the planetary gear set 1, and the second transmission member 6 realizes the connection between the engine 5 and the planetary gear set 1.

Further, the second transmission member 6 is connected to and acts on the sun gears 110 of the two planetary gear sets 1, as shown in fig. 1, and the acting force output by the engine 5 is transmitted to the two sun gears 110 through the second transmission member 6, so as to ensure the synchronous operation of the two sun gears 110. The arrangement mode enables the structure of the whole transmission system to be more compact.

The motor generator sets 4 are provided with two groups, as shown in fig. 1, the two groups of motor generator sets 4 are symmetrically arranged and are respectively connected with the two groups of planetary gear sets 1, and the motor generator sets are used for electrically driving the planetary gear sets 1 and the wheels 2.

Specifically, the motor generator 4 is coupled to the ring gear 130 of the planetary gear set 1, and the ring gear 130 is driven to rotate by the motor generator 4, wherein the motor generator 4 is preferably, but not limited to, connected to the ring gear 130 in a gear mesh manner.

The motor generator set 4 is connected with a power module 7 through a connecting circuit, and the power module 7 can realize the charging and discharging process of the motor generator set 4. The power module 7 here is preferably but not limited to a battery.

The stationary members, which include stoppers or supporting members for supporting and fixing the carrier 140, the ring gear 130, and the motor generator set 4 in actual production, provide supporting and restricting functions for the input member and the output member to ensure accuracy of the moving direction.

In the embodiment, the vehicle hybrid power transmission system is further provided with a controller, and the controller is connected to the output member, specifically, the motor generator sets 4 connected to the output member through the connecting circuit, so that the switching control, the operating speed, the operating direction and the braking control of the power generation state and the motor output state of any one motor generator set 4 can be realized independently. Here, the control connection between the controller and the motor generator set 4 belongs to the prior art, and is not described here.

In the present embodiment, brakes are provided at the first transmission member 3 and the second transmission member 6, and a certain braking resistance can be generated by controlling the brakes, and the motor generator set 4 generates a braking force by motor braking, so as to realize a stationary state of any one of the sun gear 110, the carrier 140 and the ring gear 130 of the planetary gear set 1. The brake is a common device in the art and will not be described in detail.

The specific transmission modes of the vehicle hybrid power transmission system of the embodiment comprise a pure electric mode, a pure engine mode, a combined power output mode of an engine and a motor generator set, a running power generation mode, a pure power generation mode and a reverse mode.

In the pure electric driving mode, that is, the motor generator set 4 drives the wheel 2 to rotate, at this time, the engine 5 does not output, the sun gear 110 in the two planetary gear sets 1 remains stationary, the two sets of motor generator sets 4 drive the two annular gear rings 130 to rotate, and then the annular gear rings 130 drive the planet gears 120 and the planet carrier 140 to move respectively, so as to drive the wheel 2 to advance. The rotational direction of the ring gear 130 here is set to the normal rotation.

When the running speed exceeds a certain value, the planet carrier 140 of the two planetary gear sets 1 moves and keeps the motion inertia, at the moment, the engine 5 is started, the two motor generator sets 4 stop the power output due to the motor braking, so that the annular gear ring 130 is static, and at the moment, the pure engine running mode is realized. The second transmission member 6 driven by the engine 5 drives the sun gear 110 of the two planetary gear sets 1 to move, and the sun gear 110 drives the planet carrier 140 to move through the planet gear 120, so as to drive the wheels 2 to move forwards. It is noted that the reference value of the transition travel speed between the pure electric travel mode and the pure engine travel mode is 30-50 km/h. The purpose of the engine 5 being engaged only when the vehicle speed reaches this reference value is to ensure that the driveline provides reasonable torque to the transmission output of the vehicle and to prevent stalling of the engine 5 as a result of the engine running relatively slowly.

When the rotational speed of the carrier 140 is lower than the starting speed of the engine 5, the vehicle running speed also decreases, and the setting of the engine 5-only running mode is not satisfied. The engine 5 is turned off and the electric-only mode is used instead.

When the running speed exceeds a certain value, the engine 5 is started to enter a pure engine running mode. At this time, if a stronger power output is required, the motor generator set 4 starts the motor to drive the ring gears 130 of the two planetary gear sets 1 to rotate in the forward direction. The sun gear 110 is driven by the engine 5 and the ring gear 130 is driven by the motor-generator set 4, providing more torque to the planet carrier 140, which now incorporates the power take-off mode for both the engine 5 and the motor-generator set 4.

When the battery capacity in the vehicle battery pack is low, and pure electric driving cannot be performed, the output power of the engine 5 is improved, and the two groups of motor generator sets 4 are in a power generation mode. The two sets of planetary gear sets 1 drive the ring gear 130 to rotate forward while the sun gear 110 drives the planet carrier 140 to move, so as to realize power generation while driving, and at the moment, the power generation mode is a driving power generation mode. This mode is required to be achieved when the vehicle is operating above the starting speed of the engine 5.

When the vehicle is stationary, if the battery capacity in the vehicle battery pack is too low, and therefore pure electric driving cannot be performed, the engine 5 is started to drive the sun gears 110 of the two sets of planetary gear sets 1 to move. At this time, the wheel 2 connected with the planetary carriers 140 on both sides is in a braking state, and a high rotation resistance is formed. The sun gear 110 will then drive the ring gear 130 via the planet gears 120 to move in the opposite direction, thereby achieving a pure power generation mode.

When the vehicle needs to be reversed, the engine 5 is stopped. The two sets of motor generator sets 4 drive the annular gear rings 130 of the two sets of planetary gear sets 1 to move in opposite directions, so that the planet carriers 140 on the two sides are driven to move in opposite directions. Thus realizing the reverse mode.

The vehicle and component states of the vehicle hybrid power transmission system in each transmission mode are shown as the following table:

the present embodiment achieves this by varying the torque applied in the planetary gear set 1. Specifically, as shown in FIG. 2, the theoretical torques for the planetary gear sets are related as follows:

wherein Ms is the theoretical moment of action of the planetary wheel on the sun wheel;

mr is the theoretical moment of action of the planet wheel on the annular gear ring;

mc is the theoretical moment of action of the planet carrier by the planet wheel;

k is the ratio of the number of teeth of the annular gear ring to the number of teeth of the sun gear, and is called as a characteristic parameter of the planet row.

When the pure electric drive is realized, the motor generator set 4 applies a torque to the planet wheels 120 through the annular gear ring 130, and a torque to the planet carrier 140 is formed. At this time, the sun gear 110 can be kept stationary as long as the brake at the second transmission member 6 applies a braking torque equal to or greater than the torque Ms applied to the sun gear 110 by the planetary gears 120.

When a pure engine 5 drive is achieved, the engine 5 applies a torque to the planet wheels 120 via the sun wheel 110, creating a torque to the planet carrier 140. At this time, the ring gear 130 can be kept stationary as long as the braking torque applied by the motor generator set 4 is equal to or greater than the torque Mr of the planetary gears 120 to the ring gear 130.

When the braking torque/load torque of the motor generator set 4 is smaller than the acting torque Mr of the planet gear 120 on the annular gear ring 130, the sun gear 110 can drive the planet carrier 140 to move and drive the annular gear ring 130 to move at the same time. That is, the engine 5 can drive the vehicle to run while generating electricity.

If the braking torque of the brake at the first transmission member 3 on the planet carrier 140 is greater than or equal to Mc, the sun gear 110 can directly drive the ring gear 130 to move through the planet gears 120, that is, power generation can be realized when the vehicle is stationary.

In the pure electric running mode or the combined power output running mode of the engine 5 and the motor generator set 4, when the running resistances of the two wheels 2 are different, a difference in torque of the two carriers 140 is caused, so that the two ring gears 130 form different torques. The torque difference of the ring gear 130 causes different rotational resistance when the motor generator set 4 outputs power, resulting in a motion difference. The differential function is achieved by using the difference in motion of the ring gear 130 to achieve different operating speeds of the two planet carriers 140.

Specifically, according to the torque balance principle of the planetary gear set 1, the input power of any one of the members among the sun gear 110, the carrier 140 and the ring gear 130 is split into the other two members, that is, Ps + Pr + Ph is 0. Where Ps represents the power applied to the sun gear 110, Pr represents the power applied to the ring gear 130, and Ph represents the power applied to the carrier 140. Note: when the engine 5 outputs, Ps corresponds to the input power, and Pr and Ph correspond to the output power, which are negative values with each other. The transmission torque distribution formula of the planetary gear set is as follows:

Fs*Ns+Fr*Nr+Fh*Nh＝0

wherein Fs represents the force on the sun gear;

fr represents the force on the ring gear;

fh represents the acting force on the planet carrier;

ns represents sun gear speed;

nr represents the ring gear rotational speed;

nh represents the carrier speed.

When the running resistance of the wheel 2 on one side changes, the running speed of the wheel 2 (the planet carrier 140) changes, and the moment balance of the original sun gear 110 or the ring-shaped gear 130 acting on the planet gear 120 is broken.

The planetary gear set 1 also has the following gear ratio calculation formula:

Ns+K*Nr-(1+K)*Nh＝0

where K represents the ring gear to sun gear tooth ratio, i.e. the planet row characteristic parameter.

When the engine 5 is running only, the output of the sun gear 110 at both sets of planetary gear sets 1 is synchronous and the torque is the same. The planet carrier 140 running resistance increases, which increases the torque of the planet gears 120 on the ring gear 130. As can be seen from the transmission ratio calculation formula, if the rotation speed of the original ring gear 130 is 0, Ns is (1+ K) × Nh; when the torque of the planet gears 120 on the annular gear 130 is larger than the resistance of the annular gear 130, the annular gear 130 is driven to move reversely, and Nr is not equal to 0. The speed at which the rotation speed of the carrier 140 is less than Nr equal to 0 can be calculated according to the formula.

When the pure electric drive or the combined power output drive is adopted, the increased resistance of one side wheel 2 can increase the torque of the planet wheels 120 on the annular gear 130. Since the running resistance of the ring gear 130 driven by the motor generator set 4 increases, the output balance of the motor generator set 4 is broken, resulting in a decrease in output speed. Thereby achieving a reduction in the running speed of the ring gear 130 and consequently of the side carrier 140, with a differential result. Therefore, when the wheels 2 on both sides are at different moving resistances, the differential function is achieved by the different moving speeds of the ring gear 130.

In addition, when the engine 5 outputs acting force, the matching of the power output and the running resistance can be realized by the constant ratio adjustment of the rotating speed of the ring gear 130 and the rotating speed of the planet carrier 140 when the rotating speed of the sun gear 110 (the rotating speed of the engine 5) is constant by using the transmission ratio formula of the planetary gear set 1, so that the embodiment does not need to use a clutch to balance the output power of the engine 5 and the running resistance.

The vehicle hybrid power system of the embodiment can ensure the economy of fuel use while ensuring the simplicity of the internal structure. Through the running analysis of the fuel engine model, when the gearbox of the general vehicle is in a high-speed cruising gear and has a low rotating speed, the efficiency can be relatively improved and the fuel can be saved. The common final transmission ratio (the inverse ratio of the rotating speed of the engine 5 to the rotating speed of the wheels 2) of the engine of the traditional fuel engine vehicle is about 1: 3-4, and the final transmission ratio comprises the comprehensive action result of two transmission systems of the transmission ratio of the gearbox and the transmission ratio of the differential mechanism.

As can be seen from the above-mentioned theoretical calculation formula Ns + K × Nr- (1+ K) × Nh ═ 0 for the transmission ratio of the planetary gear set 1, when the pure engine 5 is driving, the ring gear 130 is stationary, and Nr is equal to 0; it is possible to find that the relationship between the rotation speed of the engine 5 (the rotation speed Ns of the sun gear 110) and the rotation speed of the wheels 2 (the rotation speed Nh of the carrier 140) is Ns ═ 1+ K × Nh. I.e. the transmission ratio i-Nh/Ns-1 (1+ K).

The engine 5 is combined with the sun gear 110 through the second transmission component 6, the planet carrier 140 is driven to run, and the planet carrier 140 is used as a direct power output component for driving the wheels 2 to run. Since the ratio between the sun gear 110 and the planet carrier 140 is less than 1:2 (since K >1), it is possible to design to achieve exactly the same final ratio as a conventional fuel engine without adding other transmissions. Therefore, the engine 5 works in an efficient and oil-saving interval, and the characteristics of high efficiency and low oil consumption as those of a traditional fuel engine vehicle are realized.

The vehicle hybrid power output transmission device related to the embodiment is a set of simple and miniaturized devices, and can meet the design and use requirements of different vehicle driving structures. The front-drive driving mode of the layout of the front longitudinal engine 5 of the vehicle, the front-drive driving mode of the front transverse engine 5, the rear-drive driving mode of the rear longitudinal engine 5, the rear-drive driving mode of the front longitudinal engine 5 and the like can be realized, so that a driving structure suitable for the vehicle type can be designed for a vehicle designer according to the transmission principle. It should be noted that if the rear-drive mode of the front longitudinal engine 5 is implemented, it is necessary to consider the miniaturization of the motor generator set 4 and the greater encroachment of the upper space of the rear axle, which has a certain influence on the vehicle passenger space layout.

Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that modifications and variations of the present invention are possible to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hybrid drive system for a vehicle, characterized in that its body is provided with an input member provided with planetary gear sets (1) and wheels (2), said wheels (2) being provided with two, said planetary gear sets (1) being provided with two sets, said two sets of planetary gear sets (1) being connected respectively to two wheels (2).

2. A vehicle hybrid transmission system according to claim 1, characterised in that a first transmission member (3) is provided between the planetary gear set (1) and a wheel (2).

3. A vehicle hybrid transmission system according to claim 1, characterized in that the planetary gear set (1) comprises a sun gear (110), planet gears (120) and an annular ring gear (130), the planet gears (120) are arranged in a matching manner in the inner ring of the annular ring gear (130), the sun gear (110) is meshed with the planet gears (120), a planet carrier (140) is connected to one side of the planet gears (120), and the planet gears (120) are rotationally connected to the planet carrier (140).

4. A vehicle hybrid transmission system according to claim 3, characterized in that it is provided with an output member provided with motor-generator sets (4), said motor-generator sets (4) being provided with two sets, said two sets of motor-generator sets (4) being connected with two sets of planetary gear sets (1), respectively.

5. A vehicle hybrid transmission system according to claim 4, characterised in that the motor-generator set (4) is in a mating connection with an annular ring gear (130).

6. A vehicle hybrid powertrain as claimed in claim 4, characterised in that the output member comprises an engine (5), a second transmission member (6) being provided between the engine (5) and the planetary gear set (1).

7. A vehicle hybrid transmission system according to claim 6, characterised in that the second transmission member (6) is connected to and acts on the sun gear (110) of both sets of planetary gears (1).

8. A vehicle hybrid transmission system according to claim 4, characterized in that the motor-generator set (4) is provided with a power supply module (7), the power supply module (7) being connected to the motor-generator set (4) by a connection circuit.

9. The vehicle hybrid powertrain system of claim 4, wherein the body thereof is further provided with a stationary member connected with the input member and the output member.

10. The vehicle hybrid transmission system according to claim 4, further provided with a controller connected to the output member through a connection circuit.