CN210416190U

CN210416190U - Global stepless speed change transmission system with two motors connected in series

Info

Publication number: CN210416190U
Application number: CN201921078968.0U
Authority: CN
Inventors: 杨振忠
Original assignee: Guangxi Yuchai Machinery Co Ltd
Current assignee: Guangxi Yuchai Machinery Co Ltd
Priority date: 2019-07-11
Filing date: 2019-07-11
Publication date: 2020-04-28
Anticipated expiration: 2029-07-11

Abstract

The utility model discloses a universe stepless speed change transmission system with double motors connected in series, which is connected with an output shaft of an engine and comprises a first motor clutch, a first motor, a second motor, a motor controller, a gear shifting clutch, a gearbox and a storage battery; wherein the first motor and the second motor are arranged in series; the output shaft of the engine directly outputs power outwards through the power output shaft; an engine output shaft provides generated power for the first motor through the first motor clutch; the first motor provides electric energy to the second motor and the storage battery through the motor controller, and meanwhile, the second motor provides speed changing and speed regulating power through the gearbox. The utility model discloses a universe infinitely variable transmission system can keep the engine steady operation in an ideal design interval of low oil consumption, low emission under the condition that satisfies vehicle demand power, reaches whole car fuel-efficient, lowers the target of emission.

Description

Global stepless speed change transmission system with two motors connected in series

Technical Field

The utility model relates to a universe infinitely variable transmission system field for road and non-road vehicle especially is about a universe infinitely variable transmission system of bi-motor series connection.

Background

The existing tractor transmission system is divided into a manual gear shifting transmission system, a power uninterrupted automatic gear shifting transmission system and a hydraulic mechanical stepless speed change transmission system (HMCVT) according to a gear shifting mode.

1. Manual gear shifting transmission system

When the tractor works in the field, the change of land resistance is large, the load change of the whole tractor is large, the tractor adopting a manual gear shifting transmission system needs frequent stopping and gear shifting so as to meet the requirements of traction force and speed of farm tool operation, the working intensity of workers is large, the working efficiency is low, and the working quality is unstable; meanwhile, the rotating speed of the engine is directly related to the speed of the vehicle, the change range of the rotating speed of the engine is large due to the change of the speed of the whole vehicle, and the engine cannot work in a stable and economical rotating speed range, so that the oil consumption is high, the emission is poor, and the vibration and abrasion are large. The transmission system has simple structure and low manufacturing and maintenance cost, and is suitable for the current purchase level of farmers. In advanced countries of the world, manual gear shifting transmission systems are mostly applied to tractor products with horsepower below 80 Hp.

2. Continuous automatic gear shifting transmission system for power of tractor

The method refers to a gear shifting process carried out under the condition that the power from an engine to a gearbox is not interrupted during the running of a vehicle; the wet-type multi-plate clutch is used as a gear shifting executing mechanism, when gears need to be changed, two clutches for gear shifting are sequentially separated and combined according to the change of control oil pressure, and gear shifting without stopping is achieved during vehicle load running, so that the problem of stopping and gear shifting during manual gear shifting transmission system operation is solved, the operation intensity of workers is reduced, and the operation comfort and the operation efficiency are improved. However, the engine speed of the uninterrupted automatic gear shifting transmission system is directly related to the vehicle speed, the change range of the engine speed is large due to the change of the vehicle speed, the engine cannot work in a stable and economical rotating speed range, and the engine has high oil consumption, poor emission and large vibration abrasion. Meanwhile, due to the fact that the tractor has a large operation requirement and a large number of gears, the transmission structure needs a large number of clutches and proportional valves, and a 160-horsepower 16-gear gearbox is taken as an example: the full-domain automatic gearbox needs 8 clutches and 8 hydraulic proportional valves; due to the consistency, the gear shifting performance of the transmission system needs to be debugged and calibrated on a special delivery test bed, the abrasion of a clutch is increased along with the increase of the service time, the gear shifting control time is changed, the smoothness is poor, and gear shifting impact is generated. At present, the technology of the systems is basically mastered by foreign companies and mainly depends on import, and the transmission system has the disadvantages of complex structure, high price, difficult price reduction and high maintenance cost. For reasons of price, in advanced countries of the world, powershift transmissions are mostly applied to 80-200Hp tractor products.

3. Hydraulic mechanical stepless speed change transmission system (HMCVT)

The transmission system consists of a hydraulic plunger variable pump/motor/multi-row planetary mechanism/wet clutch and a brake, and has the main advantages that: the power of the engine is divided into two power routes through the planet row, one power route is a mechanical power route, and the power is directly transmitted to an input shaft of the gearbox; one is a hydraulic power route, and after the machine-liquid-machine power conversion process, the hydraulic power route and the input shaft of the gearbox realize the confluence of all power; by the power splitting and converging principle, the torque and the rotating speed of the transmission system can be automatically and continuously changed according to the speed and the traction requirement of the vehicle, and the traction and the speed requirement of the vehicle during speed change can be ensured.

The transmission system (HMCVT) realizes stepless automatic change of the vehicle transmission system, and has the advantages of low operation intensity of workers, good operation comfort, high operation efficiency and high quality; because the rotating speed and the torque of the engine are completely decoupled (irrelevant) with the speed and the traction of the whole vehicle, the engine can stably work in a low oil consumption area, and has small vibration and good emission.

The high-pressure variable plunger pump/motor, the proportional valve and the like adopted by the transmission system (HMCVT) belong to precise hydraulic coupling parts, have very high requirements on clean and clean assembly, use cleanliness and maintenance cleanliness, need special hydraulic oil and have high use and maintenance cost; the transmission gear box of the system adopts a multi-row planetary mechanism and a wet clutch or a brake to realize the regional change of 4-6 gears, the system has a large number of parts and a complex structure, the key technology of the system is basically mastered by foreign companies, products mainly depend on import, and the transmission gear box has high cost and difficult price reduction. Due to the price and the use and maintenance, the system is used in a very small amount in the Chinese market. For cost reasons, the Hydraulic Mechanical Continuously Variable Transmission (HMCVT) is mostly applied to 200-400 Hp tractor products in advanced countries of the world.

The prior art transmission systems suffer from the following disadvantages:

1. adopt manual gear shifting transmission system, simple structure, it is easy to make, maintain, it is with low costs, the shortcoming is:

(1) the tractor adopting the manual gear shifting transmission system needs frequent stopping and gear shifting to meet the requirements of traction force and speed of farm tool operation, and has the advantages of high working strength of workers, low working efficiency and unstable working quality.

(2) The rotating speed of the engine is directly related to the speed of the vehicle, the change range of the rotating speed of the engine is large due to the change of the speed of the whole vehicle, the engine cannot work in a stable and economical rotating speed range, and the engine has high oil consumption, poor emission and large vibration abrasion.

2. The uninterrupted automatic power shifting transmission system realizes the non-stop shifting during the running of the vehicle load and has the following defects:

(1) the rotating speed of the engine of the transmission system is directly related to the speed of the vehicle, the change range of the rotating speed of the engine is large due to the change of the speed of the vehicle, the engine cannot work in a stable and economical rotating speed range, and the transmission system is high in oil consumption, poor in emission and large in vibration abrasion.

(2) The transmission system needs a large number of clutches and proportional valves, the abrasion of the clutches is increased along with the increase of the service time, the gear shifting control time is changed, the smoothness is poor, and gear shifting impact is generated.

(3) The traditional power gear shifting gearbox is in single-power line stepped transmission, realizes super crawling gears (ultra-low speed), and needs to be added with a plurality of complex reduction gear trains. Furthermore, the stepless transmission during the main operations of rotary tillage and the like cannot be realized, i.e. the optimal running speed of the rotary cultivator cannot be matched theoretically

(4) At present, the technology of the systems is basically mastered by foreign companies and mainly depends on import, and the drive train has high price, difficult price reduction and high maintenance cost.

3. The hydraulic mechanical stepless speed change transmission system (HMCVT) realizes a global stepless speed change system consisting of 4-6 gears, and has the following defects:

(1) the mechanical speed change system consisting of 4-6 gears is a speed change mechanism consisting of a plurality of rows of planetary mechanisms and 4-6 wet clutches or brakes, and has the advantages of complex structure, high part processing requirement and high cost.

(2) The hydraulic power shunting system composed of the hydraulic precision matching parts has high requirements on clean and clean assembly, use cleanliness and maintenance cleanliness, needs special hydraulic oil and is high in use and maintenance cost.

(3) Since the technology of these systems is basically mastered by foreign companies, the products mainly depend on import, the cost is very high, and the price reduction is difficult.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a universe infinitely variable transmission system of bi-motor series connection, it can overcome the defect that prior art's transmission system exists well.

In order to achieve the above object, the present invention provides a global stepless speed change transmission system with two motors connected in series, which is connected with an output shaft of an engine, and comprises a first motor clutch, a first motor, a second motor, a motor controller, a gear shifting clutch, a gearbox and a storage battery; wherein the first motor and the second motor are arranged in series; the output shaft of the engine directly outputs power outwards through the power output shaft; an engine output shaft provides generated power for the first motor through the first motor clutch; the first motor provides electric energy to the second motor and the storage battery through the motor controller, and meanwhile, the second motor provides speed changing and speed regulating power through the gearbox.

In a preferred embodiment, the first electric machine comprises a first electric machine rotor and a first electric machine stator, the first electric machine rotor is rigidly connected with the clutch output first electric machine input hollow shaft, and the clutch output first electric machine input hollow shaft is connected with the engine output shaft through a first electric machine clutch; the second motor comprises a second motor rotor and a second motor stator, the second motor rotor is rigidly connected with the second motor output hollow shaft, and the second motor output hollow shaft is concentrically connected with the gearbox input hollow shaft and the gear shifting power input hollow shaft; the first motor stator and the second motor stator are jointly installed in a motor stator shared shell, and the motor stator shared shell is connected with the gearbox shell through bolts;

the engine output shaft passes through the clutch output first motor input hollow shaft and then is coaxially connected with the power output shaft, the clutch output first motor input hollow shaft passes through the second motor output hollow shaft, the engine output shaft, the clutch output first motor input hollow shaft and the second motor output hollow shaft are of a three-shaft coaxial nested structure, and meanwhile the engine output shaft also passes through the gearbox input hollow shaft and the gear shifting power input hollow shaft.

In a preferred embodiment, the front end of the clutch output first motor input hollow shaft is connected with a driven plate of an engine clutch, the rear end of the clutch output first motor input hollow shaft is connected with a driven plate of a gear shifting clutch, a driving plate of the engine clutch is connected with an output shaft of the engine, and the driving plate of the gear shifting clutch is coaxially connected with a gear shifting driving gear.

In a preferred embodiment, the gearbox comprises synchronizers and gearsets, a gearbox output shaft and a shifting driven gear. A gearbox output shaft mechanically coupled to the gear set; and the gear shifting driven gear is coaxially connected with the output shaft of the gearbox and is meshed with the gear shifting driving gear.

In a preferred embodiment, the two-motor series global continuously variable transmission system further comprises a continuously variable transmission power output mode, wherein a transmission path of the continuously variable transmission power output mode is that the engine outputs a first motor input hollow shaft through an engine clutch and the clutch to transmit mechanical power of the engine to an engine rotor to generate electricity and convert the electricity into electric power, the first motor transmits the electric power to a second motor through a motor controller to convert the electricity into mechanical power, and the mechanical power is transmitted to the outside through a transmission output shaft, a central transmission driving gear and a central transmission driven gear after being input into the hollow shaft, a synchronizer and a speed change torque of a gear set through a transmission case.

In a preferred embodiment, the global stepless speed change transmission system with two motors connected in series further comprises a stepless speed change and speed regulation mode, wherein all the power of the engine is transmitted to the first motor rotor to be converted into electric power, and the electric power is subjected to continuous stepless control on current, voltage and frequency through the motor controller, so that the output torque and the rotating speed of the second motor rotor under constant power can be regulated in a stepless manner, then the electric power is input into the transmission through the transmission input hollow shaft, and the electric power is transmitted to the tail end driving wheel through the transmission output shaft, the central transmission driving teeth and the central transmission driven teeth after the speed change and torque change of the transmission.

In a preferred embodiment, the dual-motor series connection global infinitely variable transmission system further comprises a global infinitely variable shifting mode, the first motor is switched from a power generation state to a power driving state, the motor controller generates a control signal for the rotation speed of the first motor according to the driving speed state of the vehicle at the time of shifting, the power of the first motor comes from the storage battery with high discharge rate, the driving disk of the shifting clutch is combined with the driven disk of the shifting clutch according to the logic control of the clutch during shifting, the rotor of the first motor rapidly adjusts the rotation speed to match the rotation speed of the central transmission driving gear at a certain gear at the time of shifting, and the power of the first motor is output from the output clutch to the first motor input hollow shaft, the shifting power input hollow shaft, the shifting clutch, the shifting driving gear, the shifting driven gear, the central transmission driving gear, the central transmission driven gear, Eventually reaching the drive wheels.

In a preferred embodiment, the two-motor series connection universal stepless speed change transmission system further comprises a crawling and slow running speed obtaining mode, when the vehicle needs a very low running speed, the rotor of the second motor outputs running power to the input hollow shaft of the gearbox, under the working condition, the output shaft of the engine provides most of engine power to rear end power utilization equipment through the power output shaft, and the running speed of the vehicle is controlled by the rotating speed of the second motor, so that the condition that the vehicle is in a low-speed and high-torque running state can be met.

In a preferred embodiment, the universal continuously variable transmission system with two motors connected in series further comprises a reverse gear mode, the motor controller inputs reverse current and voltage to control the second motor to rotate in reverse, and reverse power of the second motor outputs reverse power through the second motor output hollow shaft, the gearbox input hollow shaft, the central transmission driving gear and the central transmission driven gear.

In a preferred embodiment, the universal continuously variable transmission system with two motors connected in series further comprises a starting power assisting mode, when the vehicle is started under heavy load, the universal continuously variable transmission system is in a hybrid power state in a short period, at the moment, the power of the second motor is from two paths, one path is that the engine generates electric power through the first motor, and the electric power is transmitted to the second motor through the motor controller to convert the electric power into mechanical power; the other path is that the electrifying machine controller provides electric power to the second motor by the storage battery; the superimposed value of the electric power of the two paths will be greater than the rated power of the engine.

In a preferred embodiment, the electric power superposition value of the two paths is between 1.5 and 1.8 times of the rated power of the engine.

In a preferred embodiment, the dual-motor tandem global infinitely variable transmission system further comprises a motor bearing cap and a central drive rear axle housing. The motor bearing covers are arranged at two ends of the motor stator shared shell; the central transmission rear axle housing body is used for accommodating the central transmission driving gear, the central transmission driven gear, the differential half shaft output gear and the half shaft.

Compared with the prior art, the utility model discloses a universe infinitely variable transmission system of bi-motor series connection has following beneficial effect: the engine is connected with the first motor through a clutch or a shock absorber, the power of the engine is completely converted into power generation power, all the electric power is output to the second motor through the electric power conversion module, the stepless change of the output torque and the rotating speed of the second motor is realized through the control of the motor controller on the current, the voltage and the frequency, and the vehicle can work in a CVT mode. A power independent transmission line of a second motor is designed, the independent line is not overlapped with a power transmission line of a gearbox, automatic gear shifting of gears of the gearbox with 4-6 gears is achieved, the motor is guaranteed to work in a high-efficiency area, and therefore the whole machine can realize global stepless speed change from zero to the maximum designed speed range. The automation of field operation driving is realized, the labor intensity of workers is greatly reduced, and the operation efficiency and quality are improved; meanwhile, the motor has high response speed, excellent gear shifting smoothness and short gear shifting time, so that the friction work of the gear shifting clutch is reduced, and the service life and the reliability of the clutch are improved. The dual-motor series structure realizes complete decoupling (independent and irrelevant) of the torque and the rotating speed of the engine and the traction force and the speed of a vehicle, the engine can stably run in an optimized low-oil-consumption area, the oil consumption of the engine is reduced by more than 10%, the requirements of emission policies and regulations are easily met, and the vibration and the abrasion of the engine are reduced. The speed of the tractor running system is independent of the rotating speed of the power output shaft of the engine, so that the best matching point of the running speed and the theoretical rotating speed of the farm tool can be found, the working efficiency is improved, and the oil consumption and the emission are reduced. The ultra-low speed crawling gear function can be realized by utilizing the low-speed and high-torque characteristics of the permanent magnet alternating current motor, the permanent magnet alternating current motor stably works in the driving speed range of 0-0.1km/h, and most of engine power is output through a power output shaft and is used for special operations such as ditching and the like. Reverse gear is not needed to be arranged in the gearbox, and any reverse speed of 0-Vmax km/h can be realized by means of the reverse rotation of the second motor, so that various operation requirements of the tractor are met. By means of the rated power or instantaneous high power function of the second motor, the power-assisted vehicle starts at low speed and heavy load, the ground acceleration time and the land blocks which are not operated are reduced, and the crop sowing area is increased. The gearbox can be designed into a 4-6-gear fixed shaft type gearbox according to the power of the tractor, a synchronizer gear shifting structure is adopted, the gearbox is simple and reliable in structure, parts are greatly reduced, the transmission efficiency is high, and the cost is low. The main key parts, the high-power permanent magnet synchronous motor and the motor controller, the high-power discharge battery and other technologies and products are completely mastered by local manufacturers and produced in a large scale, and the local purchasing channel is wide. Due to the high reliability and low cost of the motor and the controller, the manufacturing, using and maintaining cost of the transmission system is greatly reduced.

Drawings

Fig. 1 is a schematic structural diagram of a global continuously variable transmission system according to an embodiment of the present invention.

Fig. 2 is a block diagram of an electric power conversion module of a global continuously variable transmission system according to an embodiment of the present invention.

Description of the main reference numerals:

1-a first motor clutch, 2-a flywheel, 3-an engine, 4-an engine output shaft, 5-a clutch output first motor input hollow shaft, 6-a motor bearing cap, 7-a motor stator common housing, 8-a first motor stator, 9-a first motor rotor, 10-a second motor stator, 11-a second motor rotor, 12-a second motor output hollow shaft, 13-a gearbox input hollow shaft, 14-a gearbox housing, 15-a shift driving gear (Z1), 16-a shift clutch driven disk, 17-a shift clutch driving disk, 18-a shift power input hollow shaft, 19-a power output shaft, 20-a center drive rear axle housing, 21-a differential half shaft output gear and a half shaft, 22-a center drive driven gear, 23-central drive pinion, 24-shift driven gear (Z2), 25-gearbox output shaft.

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited by the following detailed description.

Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

As shown in fig. 1, fig. 1 is a schematic structural diagram of a universal continuously variable transmission system according to an embodiment of the present invention. According to the utility model discloses preferred embodiment's universe continuously variable transmission system of bi-motor series connection, engine output shaft 4 passes through in clutch output first motor input hollow shaft 5, clutch output first motor input hollow shaft 5 passes through in second motor output hollow shaft 12, three axles are coaxial nested structure, clutch output first motor input hollow shaft 5 simultaneously, gearbox input hollow shaft 13, 18 triaxial of power input hollow shaft of shifting are connected with the axle center, engine output shaft is also connected with the axle center of power output shaft from gearbox input hollow shaft 13 and the power input hollow shaft of shifting through the back simultaneously.

In some embodiments, the MG1 first motor stator 8 and the MG2 second motor stator 10 are mounted in a common motor stator housing 7. The MG1 first motor rotor 9 is rigidly connected to the clutch output first motor input hollow shaft 5 and coupled to the driven plate of the first motor clutch 1 to receive the power output from the engine 3 to generate electricity. The engine 3 is mechanically connected with an engine output shaft 4, and the engine output shaft 4 outputs the first motor input hollow shaft 5 to a power output shaft 19 through a clutch. The MG2 second motor rotor 11 is mechanically connected to the second motor output hollow shaft 12 and outputs power through the second motor output hollow shaft 12 to the transmission input hollow shaft 13. The hollow gearbox input shaft 13, a synchronizer, a gear set and a gearbox output shaft 25 of the gearbox form a fixed shaft type 4-6 gear gearbox, the gearbox output shaft 25 is mechanically connected with a central transmission driving gear 23, and power after speed changing is transmitted to the central transmission driving gear 23 and a central transmission driven gear 22 through the gearbox output shaft 25 and then transmitted to a tractor driving wheel through tail end speed reduction transmission (not shown). The first motor MG1 and the second motor MG2 of the present embodiment both use permanent magnet synchronous ac motors, which have low-speed and high-torque characteristics and the function of interchanging the second motor with the first motor at any time.

In some embodiments, the clutch output first motor input hollow shaft 5 is mechanically connected to the shift power input hollow shaft 18, and the shift clutch driving plate 17 is mechanically coupled to the shift power input hollow shaft 18. The first motor stator 8 and the second motor stator 10 are in bolt connection with a rear transmission case 14 through a motor stator shared case 7, and motor bearing covers 6 are arranged at two ends of the motor stator shared case 7.

With reference to fig. 1, in some embodiments, the universal stepless transmission system with two serially connected motors of the present invention further includes a stepless transmission power output mode, wherein the transmission path of the universal stepless transmission power output mode is that all the power of the engine 3 is converted into electric power through the clutch 1 → the first motor input hollow shaft 5 → the first motor rotor 9, the electric power is converted into mechanical power through the electric power conversion module (which includes elements such as a motor controller) → the second motor MG2, and the mechanical power is further converted into mechanical power through the second motor output hollow shaft 12 → the transmission input hollow shaft 13 → after the transmission is shifted and twisted, and then passes through the transmission output shaft 25 → the central transmission driving gear 23 → the central transmission driven gear 22 → the end transmission (not shown) → the driving wheel (not shown).

Referring to fig. 1, in some embodiments, the two-motor series global stepless speed change transmission system of the present invention further includes a stepless speed change speed regulation mode, the transmission path of the system is that the power of the engine 3 is completely converted into the electric power of the MG1 first motor rotor 9, and the whole electric power is continuously and steplessly controlled by the electric power conversion module to the current, voltage and frequency, so as to realize the stepless regulation of the output torque and the rotation speed of the MG2 second motor rotor 11 under the constant power, and the output torque and the rotation speed are input to the transmission input hollow shaft 13, and after the transmission is changed in speed and torque, the output shaft 25 → the central transmission driving gear 23 → the central transmission driven gear 22 → the end transmission (not shown) → the driving wheel (not shown) to satisfy the condition that the vehicle is in the stepless speed change (CVT. Structurally, the power of the whole range stepless speed change transmission system is all input by the MG2 second electric machine, therefore, the function of the transmission system stepless speed Change (CVT) is determined by the constant power stepless speed change capability of the second electric machine.

Referring to fig. 1, in some embodiments, the dual-motor serial universal continuously variable transmission system of the present invention further includes a universal continuously variable transmission mode, the overall speed range of the tractor is 0-50km/h, and a dead axle gearbox with 4-6 gears is set according to different requirements of tractor power, so as to ensure that the first motor MG1 and the second motor MG2 can work in a high efficiency region within the full speed range of the tractor, thereby improving the overall efficiency of the transmission system.

In the shift mode: the MG1 first motor rotor 9 changes from the power generation state to the electric state, the vehicle control unit (VCU not shown) generates a rotation speed control signal of the first motor MG1 (switched to the second motor state at this time) according to the speed state of the tractor at the gear shifting moment, the power of the first motor comes from the high discharge rate storage battery at this time, the clutch driven plate 16 of the gear shifting clutch is combined with the clutch driving plate 17 of the gear shifting clutch according to the logic control requirement of the clutch during the gear shifting, the MG1 first motor rotor 9 rapidly adjusts the rotation speed to match with the rotation speed of the central transmission driving gear 23 at a certain gear at the gear shifting moment; the first motor MG1 outputs power through the clutch, the first motor input hollow shaft 5 → the shift power input shaft 18 → the shift clutch driven plate 16 is coupled to the shift clutch driving plate 17 → the shift driving gear 15(Z1) → the shift driven gear 24(Z2) → the center drive driving gear 23 → the center drive driven gear 22 → finally to the drive wheels. At this moment, the MG1 first electric machine directly provides load power to the tractor central transmission gear 23 through an independent shifting transmission route and a power route crossing the transmission input hollow shaft 13, and the MG1 first electric machine rotor 9 bears the whole power of the whole vehicle during shifting at this moment through the independent shifting transmission route.

At this time, the process of the Vehicle Control Unit (VCU) (not shown) sending a speed regulation signal to the MG2 second motor according to the real-time rotation speed signal of the central transmission driving gear 23 and the target gear is as follows: the second motor MG2 receives an instruction to enter an unloading state → a second motor state → a speed tracking and regulating mode, the rotating speed of the hollow shaft 13 input by the gearbox is regulated to reach a synchronous gear-disengaging rotating speed range, the TCU (a speed change controller not shown) sends an instruction signal to the gear-shifting executing mechanism, the gear-shifting executor is disengaged, and the gear-disengaging process of the structure needs the second motor MG2 to actively regulate the speed and disengage the gear because the second motor has large rotating inertia and the synchronizer is difficult to disengage the gear.

In the gear engaging state: at the moment, the MG1 first motor rotor 9 is still in the original power rotating state, the MG2 second motor rotor 11 adjusts the rotating speed of the transmission input hollow shaft 13 by adjusting the rotating speed of the MG2 second motor according to the rotating speed requirement of the target gear, so as to reach the synchronous rotating speed requirement of the target gear synchronizer, and the gear shifting execution mechanism executes the gear engaging action from the neutral position. After the gear is engaged, the MG1 first motor rotor 9 is unloaded to enter a power generation rotation state, the shift clutch driven disc 16 is separated from the shift clutch driving disc 17, the MG2 second motor rotor 11 is converted to normal driving power, power is input into the hollow shaft 13 of the gearbox, and after the speed and the torque of the gearbox are changed, the power is transmitted to the driving wheels through the central transmission driving gear 23 and the central transmission driven gear 22. Realize the driven incessant connection of whole car universe CVT.

All gear shifting processes are the same, in the driving gear shifting process, the opening degree of an engine accelerator is unchanged, and the rotating speed of the transmission input hollow shaft 13 is adjusted by utilizing the quick-response rotating speed change of the second motor MG2, so that the gear shifting requirement of the synchronizer is met. Because the power transmission soft connection characteristic of the series motor of the universal stepless speed change transmission system does not have a mechanical power transmission route, and the rotating speed and the torque of the engine 3 are decoupled (irrelevant) with the rotating speed and the torque of the rotor 11 of the second motor of the MG2, the transmission system can eliminate a clutch at the output end of the engine.

It should be noted that, in some embodiments, the utility model discloses a shift process has two kinds of first motor MG 1's mode of operation, one kind is when first motor MG1 gets into the mode of shifting, first motor clutch 1 separates with engine output shaft 4, and the first electric motor rotor 9 of MG1 only exports the tractive power when shifting, and first motor MG1 power consumption is little under this kind of operating mode, but shift control has increased the separation process of combining of first motor clutch 1, and control is relatively more complicated.

The other is that when the first motor MG1 enters the shift mode, the engine 3 enters the fuel cut-off mode, the first motor clutch 1 is not separated from the engine output shaft 4, and the MG1 first motor rotor 9 needs to output the traction power during the shift and the power for dragging the engine to run, under the condition, the power consumption of the first motor MG1 is large, but the shift control is relatively simple.

Referring to fig. 1, in some embodiments, the dual-motor series global stepless transmission system of the present invention further includes a crawling and slow-moving speed obtaining mode, when the vehicle needs a very low moving speed, the MG2 second motor rotor 11 outputs moving power to the transmission input hollow shaft 13, and under this condition, the engine output shaft 4 provides most of the engine power to the rear end working equipment (e.g. agricultural machinery, etc.) through the power output shaft 19. The running speed of the vehicle is controlled by the rotating speed of the rotor 11 of the MG2 second motor, and the running speed of the vehicle can be controlled to a stable transition state close to 0-0.1km/h due to the low-speed and high-torque characteristics of the permanent magnet synchronous alternating current motor.

Referring to fig. 1, in some embodiments, the dual-motor serial universal stepless transmission system of the present invention further includes a reverse mode, wherein the reverse mode includes a path for inputting reverse current and voltage to the motor controller to control the MG2 to rotate in reverse direction, and reverse power of the MG2 second motor is outputted through the second motor output hollow shaft 12 → the transmission input hollow shaft 13 → the central transmission main gear, the central transmission driving gear 23, and the central transmission driven gear 22. The utility model discloses under the mode of reversing gear, can realize and go the same speed of going backwards that gos forward.

With reference to fig. 1, in some embodiments, the dual-motor serial-connection universal stepless speed change transmission system of the present invention further includes a starting power-assisted mode, when the tractor starts under heavy load, at this time, the transmission system is in a hybrid power state for a short time, and the power of the MG2 second motor rotor 11 is obtained by two power superposes; the transmission path of one power is as follows: the mechanical power of the engine 3 is converted into electric power by the MG1 first electric machine rotor 9, and the electric power is passed → the electric power conversion module → the MG2 second electric machine rotor 11; the other power comes from a storage battery, and the transmission path of the other power is the storage battery → the MG2 motor controller → the MG2 second electric motor rotor 11; due to the peak power characteristics of the pmsm, the peak power of the MG2 second motor is generally matched to match the rated power of the engine 3 (although the present invention is not limited thereto, and the peak power of the first/second motor may be matched as required). The input power of the MG2 second electric machine is between rated power and peak power; the magnitude of the boosting power depends on an accelerator opening interval of an operator, the larger the accelerator opening, the higher the engine rotating speed, and the larger the power obtained by the first motor MG1 and the second motor MG2, so that the power during starting and accelerating can generally reach 1.5-1.8 times of the rated power of the engine, the requirement on the low-speed starting performance of the engine is greatly reduced, the acceleration starting distance of the whole vehicle is reduced, and the area of the land which is not operated is reduced.

As shown in fig. 2, fig. 2 is a schematic diagram of an electric power conversion module of a motor controller of a continuously variable transmission system according to an embodiment of the present invention. In some embodiments, during forward driving conditions: the utility model discloses a whole power of engine 3(ICE) is transmitted to MG1 first electric motor rotor 9 through first motor clutch 1 and clutch output first motor input hollow shaft 5, and engine 3 does not have mechanical rigid connection with whole transmission system; power from the first electric machine rotor 9 of MG1 → via AC/DC commutation → via DC/AC inversion → to the second electric machine rotor 11 of MG2 → the transmission input hollow shaft 13 → the transmission output shaft 25 → the central drive gear 23 → the central drive driven gear 22 → final drive → drive wheels.

Under the non-gear-shifting working condition, the electric power conversion module system sends an instant instruction for charging the energy storage device according to the SOC charge value (electric quantity level) of the energy storage device, and the power of the first motor MG1 enters the storage battery; when the charge value of the SOC of the storage battery meets the requirement, the charging circuit is automatically closed, and the charge supplement is stopped.

The energy storage device provides short-term power for the MG1 first motor/second motor MG2 during gear shifting, so that the gear shifting function is realized; under the working conditions of ECVT and crawling speed, the first motor MG1 generates electricity and provides electric power for the second motor MG2, and the second motor MG2 generates running power meeting the requirement through the transmission input shaft 13. When the vehicle is reversed, the first motor MG1 generates power, the second motor MG2 is controlled by the motor controller to input reverse voltage and current, and the second motor MG2 generates reverse power to drive the working vehicle to move backwards. During power assisting, the electric power generated by the first motor MG1 and the power provided by the energy storage device provide power for the second motor MG2, and the second motor MG2 is in the peak power mode at the moment, so that the power-assisted tractor starts to accelerate. The working condition of the non-road tractor is basically different from the working condition of an urban road, so that the conditions of long-time idling, long-distance slow braking, free running deceleration and the like rarely exist, and the working condition of energy recovery is few. The second motor MG2 and the electric power conversion module system have the capability of recovering energy, but are not designed with the aim of recovering energy.

The above embodiment is only an example of a tractor, but the present invention is not limited thereto, and both road and off-road vehicles are applicable.

To sum up, the utility model discloses a universe infinitely variable transmission system of bi-motor series connection has following advantage:

1. the engine power is transmitted by the structure of the soft connection of the motor power according to the characteristics of the low-speed large-torque section and the constant-power section of the second motor through the independent action of the two permanent magnet synchronous alternating current motors, and the link of directly and mechanically connecting and transmitting the engine power is eliminated; the incidence relation between the traction force and the speed of the vehicle and the torque and the rotating speed of the engine is released; the continuous stepless change (ECVT) of the speed ratio of the transmission system is realized by means of the stepless speed change characteristic of the constant power section of the second motor; the transmission system can keep the engine stably running in an ideal design interval with low oil consumption and low emission under the condition of meeting the power requirement of the vehicle, and achieves the aims of saving oil and reducing emission of the whole vehicle.

2. The utility model discloses a stepless speed change system (ECVT) adopts the two motor structures of the shared stator casing of establishing ties, and the two motors of shared stator casing can share rotor axial space, and shared motor MG1 MG2 cooling water course, common power cable space, the motor integrates the degree height, has reduced the motor total volume under the equal power, the at utmost has utilized the axial space of drive train.

3. The utility model discloses a two motor series connection universe infinitely variable transmission system is different from the plunger pump/motor drive system of hydraulic power reposition of redundant personnel scheme (HMCVT), and the motor performance is last: the response speed of 0 to large rotating speed and large torque is 2-3 times faster than that of a hydraulic pump system, the speed control accuracy is superior to that of a hydraulic pump/motor system, and the use and maintenance cost is high: the motor is simple to maintain and reliable to use, no running pollution is generated, the requirements on the cleanliness of the hydraulic pump and the motor are very high, and the maintenance cost is very high. Cost and purchase: the equivalent power cost of the permanent magnet synchronous motor is about half of that of a hydraulic pump/motor, and local manufacturers completely master the research and development production technology of the motor.

4. The utility model utilizes the double motors and the independent power transmission lines to realize the automatic gear shifting of all the gears of the gearbox; the fixed-shaft gear transmission is combined with an independent gear shifting route, and the mechanism is different from a traditional hydraulic pressure (HMCVT) multi-row planetary mechanism and a wet clutch or a brake which must be adopted, so that the manufacturing and assembling difficulty is greatly reduced, the number of parts under the same gear is greatly reduced, and the manufacturing cost is reduced; the reliability of product design is improved, and the use and maintenance cost of the product is reduced.

5. The utility model discloses utilize the bi-motor, full play second motor peak power is the characteristics more than 2 times of rated power, design power battery and power circuit guarantee driving motor MG2 peak power's short-term release, the volume of MG2 motor has been reduced, under the starting acceleration mode, adopt short-term hybrid mode, increase whole machine power 1.5-1.8 times, the greatly reduced starting acceleration distance, this shows that increased under equal farmland area by the proportion of operation land area, crop output has been increased. The hybrid mode may also be applied to short term tractor obstacle detouring and short term drag overcoming, depending on the control program settings. Traditional hydraulic pressure (HMCVT) adds the multi-row planetary mechanism drive train, can not produce at present the utility model discloses a function of hybrid power, the starting acceleration time is long.

6. The utility model discloses a (ECVT) can realize that tractor traveling system speed is independent of engine power output shaft's rotational speed to can seek the best speed matching point of theory with driven agricultural implement, improve the operating efficiency, reduce oil consumption, emission. Because permanent magnet alternating current motor's low-speed big torque characteristic, the utility model discloses a can realize the ultralow speed function of crawling, at the travel speed within range steady operation of 0-0.1km/h to export most engine power through power output shaft (19), be used for special operations such as ditching.

7. The utility model discloses a (ECVT) need not set up the reverse gear in the gearbox, relies on the counter rotation of second motor MG2 (11), can realize 0-Vmax km/h's the reverse speed of design, satisfies the various operation requirements of tractor.

8. The utility model discloses a (ECVT) main key spare part, high-power PMSM and machine controller, technologies and products such as high power discharge battery, local firm masters and large-scale production completely, and the localization purchase channel is broad. Due to the high reliability and low cost of the motor and the controller, the manufacturing, using and maintaining cost of the transmission system is lower than that of the HMCVT transmission system consisting of the hydraulic components.

9. The utility model discloses an (ECVT) has realized that the field operation is automatic that traveles, has reduced staff's intensity of labour by a wide margin, has improved operating efficiency and quality.

10. The utility model discloses a (EMCVT) is furnished with high-power first motor MG1, through standardized output interface, the electric power of outwards exporting regulated voltage, frequency provides the electric power for the operation machines that need the electric power, has enlarged and has been equipped with the utility model discloses a complete machine working range.

The foregoing description of the specific exemplary embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application, to thereby enable others skilled in the art to make and use the invention and various exemplary implementations and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.

Claims

1. A global stepless speed change transmission system with two motors connected in series is connected with an output shaft of an engine, and is characterized in that the global stepless speed change transmission system comprises a first motor clutch, a first motor, a second motor, a motor controller, a gear shifting clutch, a gearbox and a storage battery;

wherein the first and second electric machines are arranged in series; the engine output shaft directly outputs power outwards through the power output shaft; the engine output shaft provides generated power to the first motor through the first motor clutch; the first motor provides electric energy for the second motor and the storage battery through the motor controller, and meanwhile, the second motor provides speed changing and speed regulating power through the gearbox.

2. The dual-motor series global continuously variable transmission system of claim 1, wherein said first motor comprises a first motor rotor rigidly connected to a clutch output first motor input hollow shaft connected to said engine output shaft through said first motor clutch and a first motor stator; the second motor comprises a second motor rotor and a second motor stator, the second motor rotor is rigidly connected with a second motor output hollow shaft, and the second motor output hollow shaft is concentrically connected with the gearbox input hollow shaft and the gear shifting power input hollow shaft; the first motor stator and the second motor stator are jointly installed in a motor stator shared shell, and the motor stator shared shell is connected with a gearbox shell through bolts;

3. The dual-motor series global continuously variable transmission system of claim 2, wherein the front end of the clutch output first motor input hollow shaft is connected with the driven plate of the engine clutch, the rear end of the clutch output first motor input hollow shaft is connected with the driven plate of the shift clutch, the driving plate of the engine clutch is connected with the engine output shaft, and the driving plate of the shift clutch is coaxially connected with the shift driving gear.

4. The dual-motor tandem global continuously variable transmission system of claim 3, wherein the transmission comprises:

a synchronizer and a gear set;

a gearbox output shaft mechanically coupled to the gear set; and

and the gear shifting driven gear is coaxially connected with the output shaft of the gearbox and is meshed with the gear shifting driving gear.

5. The universal stepless speed-changing transmission system with two motors connected in series as claimed in claim 4, further comprising a stepless speed-changing power output mode, wherein the transmission path is that the engine outputs a first motor input hollow shaft through the engine clutch to transmit the mechanical power of the engine to the engine rotor for generating electricity and converting into electric power, the first motor transmits the electric power to the second motor through the motor controller and then converts into mechanical power, and the mechanical power outputs driving power outwards through the transmission output shaft, the central transmission driving gear and the central transmission driven gear after the speed-changing torque of the transmission input hollow shaft, the synchronizer and the gear set.

6. The global stepless speed change transmission system with two motors connected in series as claimed in claim 5, further comprising a stepless speed change and speed regulation mode, wherein the power of the engine is completely transmitted to the first motor rotor to be converted into electric power, the electric power is continuously and steplessly controlled by the motor controller for current, voltage and frequency, the stepless regulation of the output torque and the rotation speed of the second motor rotor under constant power can be realized, then the electric power is input into the transmission through the transmission input hollow shaft, and the electric power is transmitted to a tail end driving wheel through the transmission output shaft, the central transmission driving gear and the central transmission driven gear after the speed change and the torque change of the transmission.

7. The universal continuously variable transmission system with two serially connected motors as claimed in claim 5, further comprising a universal continuously variable shift mode, wherein the first motor is switched from a power generation state to a power driving state, the motor controller generates a rotation speed control signal for the first motor according to a driving speed state of the vehicle at a shift time, the power of the first motor is from the battery with a high discharge rate, the shift clutch driving plate is coupled to the shift clutch driven plate according to a logic control of the clutch during shifting, the first motor rotor rapidly adjusts a rotation speed to match the rotation speed of the central transmission driving gear at a certain gear at the shift time, and the power of the first motor is outputted through the output clutch to the first motor input hollow shaft, the shift power input hollow shaft, the shift clutch, The gear-shifting driving gear, the gear-shifting driven gear, the central transmission driving gear, the central transmission driven gear and finally reach a driving wheel.

8. The universal continuously variable transmission system with two serially connected motors as claimed in claim 5, further comprising a crawling and slow speed obtaining mode, wherein when the vehicle needs to run at a low speed, the rotor of the second motor outputs the running power to the hollow input shaft of the gearbox, and the output shaft of the engine provides most of the engine power to the rear end power utilization equipment through the power output shaft under the condition that the running speed of the vehicle is controlled by the rotating speed of the second motor.

9. The dual-motor series global infinitely variable transmission system of claim 5, further comprising a reverse mode, wherein the motor controller inputs reverse current and voltage to control the second motor to rotate in reverse, and reverse power of the second motor is outputted through the second motor output hollow shaft, the transmission input hollow shaft, the central transmission driving gear and the central transmission driven gear.

10. The universal continuously variable transmission system with two motors connected in series as claimed in claim 5, further comprising a start assisting mode, when the vehicle needs to be started under heavy load, the universal continuously variable transmission system is in a hybrid state in a short period, the power of the second motor is from two paths, one path is that the engine generates electric power through the first motor, and the electric power is transmitted to the second motor through the motor controller to convert the electric power into mechanical power; the other path is that the storage battery supplies electric power to the second motor through the motor controller; the superimposed value of the electric power of the two paths will be greater than the rated power of the engine.

11. The universal continuously variable transmission system with two motors connected in series as claimed in claim 10, wherein the electric power superposition value of the two paths is between 1.5 and 1.8 times of the rated power of the motor.

12. The dual-motor tandem global infinitely variable transmission system of claim 10, further comprising:

motor bearing covers arranged at two ends of the motor stator common shell; and

and the central transmission rear axle housing is used for accommodating the central transmission driving gear, the central transmission driven gear, the differential half shaft output gear and the half shaft.