CN-121973614-A - Tractor diesel-electric hybrid power system based on gear coupling and control method

CN121973614ACN 121973614 ACN121973614 ACN 121973614ACN-121973614-A

Abstract

A diesel-electric hybrid power system of a tractor based on gear coupling and a control method thereof belong to the field of hybrid power of the tractor and comprise a diesel engine, a first motor, a second motor, a gear coupling device, a power output speed changer and a walking speed changer, wherein the diesel engine is mechanically connected with the first motor to output rotary power to the power output speed changer, an output shaft of the first motor and an output shaft of the second motor output traction power to the walking speed changer through the gear coupling device, torque coupling of multiple power sources is realized through cooperative control of three groups of gears and clutches matched with the output shafts of the first motor and the output shafts of the second motor, the structure is simple, the operation reliability is high, the first motor and the second motor both have driving and power generation functions, the working mode of the tractor is determined according to the actual working condition requirements, and the advantages of three groups of power architectures of serial connection, parallel connection and parallel connection are matched, and cooperative lifting of high mobility and energy utilization efficiency are synchronously realized under complex operation scenes.

Inventors

LIU MENGNAN
CAO XIANCHAO
LEI SHENGHUI
WEI TAO
ZHAO CHENHUI
WANG JIANHUA
XU LIYOU
LI YANYING
LI CHUNPING
XING SHOUCHEN

Assignees

洛阳拖拉机研究所有限公司

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (9)

1. A tractor diesel-electric hybrid power system based on gear coupling comprises a diesel engine (1), a first motor (16), a second motor (15), a gear coupling device (10), a power output transmission (12) and a walking transmission (14), wherein the diesel engine (1) is connected with a first motor output shaft (1011) of the first motor (16), and the first motor output shaft (1011) is connected with the power output transmission (12) to output rotary power; The first motor (16) and the second motor (15) are in two working states of power generation and power output, so that the first motor (16) can be driven by the diesel engine (1) to generate power to supplement the electric quantity of a storage battery, or the first motor output shaft (1011) is driven to operate by the power supply of the storage battery, and the second motor (15) can be driven by the power supply of the storage battery to operate the second motor output shaft (1012), or the electric quantity of the storage battery is supplemented by the power generation recovered by the walking transmission (14); The gear coupling device (10) comprises a gear coupling device output shaft (1010) connected to a walking transmission (14), wherein a power transmission path is formed between a first motor output shaft (1011) and the gear coupling device output shaft (1010) through a gear speed change mechanism, a second motor output shaft (1012) is connected with a second motor output shaft driving gear (1001), and the second motor output shaft driving gear (1001) is meshed with a second motor output shaft driven gear (1009) arranged on the gear coupling device output shaft (1010) to form a power transmission path between the gear coupling device output shaft (1010) and the second motor output shaft (1012); The gear speed change mechanism is connected with a first motor output shaft (1011) through a speed change clutch, a second motor output shaft driving gear (1001) is connected with a second motor output shaft (1012) through a second motor output shaft driving gear clutch (1002), and the first motor output shaft (1011) and the second motor output shaft (1012) can independently transmit power to a walking transmission (14) or jointly couple to transmit power to the walking transmission (14) by controlling the clutch state of the speed change clutch and the second motor output shaft driving gear clutch (1002).
2. A tractor diesel-electric hybrid system based on gear coupling according to claim 1, characterized in that the diesel engine (1) and the first motor (16) have independent drive modes for individually driving the first motor output shaft (1011) and parallel drive modes for jointly driving the first motor output shaft (1011).
3. The diesel-electric hybrid power system of the tractor based on gear coupling, as set forth in claim 1, characterized in that the gear speed change mechanism comprises a first motor output shaft primary driving gear (1003), a first motor output shaft secondary driving gear (1005), a first motor output shaft primary driven gear (1008) and a first motor output shaft secondary driven gear (1007), the speed change clutch comprises a first motor output shaft primary driving gear clutch (1004) and a first motor output shaft secondary driving gear clutch (1006), the first motor output shaft primary driven gear (1008) and the first motor output shaft secondary driven gear (1007) are mechanically connected with the gear coupling device output shaft (1010), the first motor output shaft primary driving gear (1003) is connected with the first motor output shaft (1011) through the first motor output shaft primary driving gear clutch (1004) and is meshed with the first motor output shaft primary driven gear (1008), and the first motor output shaft secondary driving gear (1005) is connected with the first motor output shaft (1011) through the first motor output shaft secondary driving gear clutch (1006) and is meshed with the first motor output shaft secondary driven gear (1007).
4. A tractor diesel-electric hybrid system based on gear coupling according to claim 1, wherein the first motor output shaft (1011) and the second motor output shaft (1012) are nested, and the first motor output shaft (1011) coaxially penetrates through the second motor output shaft (1012) and then is connected to the gear coupling device (10).
5. A tractor diesel-electric hybrid powertrain based on gear coupling as set forth in claim 1 wherein the power take-off transmission (12) includes a power take-off transmission clutch (1201), a power take-off transmission second shaft first gear (1202), a power take-off transmission synchronizer (1203), a power take-off transmission second shaft second gear (1204), a power take-off transmission output shaft (1205), a power take-off transmission first shaft second gear (1206) and a power take-off transmission first gear (1207), the power take-off transmission first shaft second gear (1206) being mechanically connected to the power take-off transmission first shaft first gear (1207) and being connected to the first motor output shaft (1011) by the power take-off transmission clutch (1201), the power take-off transmission second shaft first gear (1202) and the power take-off transmission second shaft second gear (1204) being respectively meshed with the power take-off transmission first shaft first gear (1207) and the power take-off transmission first shaft second gear (1206), the power take-off transmission second gear (1202) being connected to the power take-off transmission output shaft (1203) through the power take-off synchronizer (1204) and the power take-off transmission second shaft (1204) being connected to the power take-off transmission second gear (1203).
6. A tractor diesel-electric hybrid system based on gear coupling as set forth in claim 1 wherein the traveling transmission (14) comprises a first shaft input gear (1401), a two-speed synchronizer (1402), a first shaft output gear (1403), a traveling transmission output shaft (1404), a second shaft output gear (1405) and a second shaft input gear (1406), the first shaft input gear (1401) is mechanically connected to the gear coupling output shaft (1010) and meshes with the second shaft input gear (1406), the second shaft output gear (1405) is mechanically connected to the second shaft input gear (1406) and meshes with the first shaft output gear (1403), and the first shaft input gear (1401), the first shaft output gear (1403) and the traveling transmission output shaft (1404) are connected by the two-speed synchronizer (1402).
7. A tractor diesel-electric hybrid system based on gear coupling as set forth in claim 1, wherein the traveling transmission output shaft (1404) of the traveling transmission (14) is further connected with a transfer case (13), the transfer case (13) comprises a transfer case input gear (1301), a transfer case intermediate gear (1302), a transfer case clutch (1303), a transfer case front output shaft (1304) and a transfer case output gear (1305), the transfer case input gear (1301) is mechanically connected with the traveling transmission output shaft (1404) and meshed with the transfer case intermediate gear (1302), the transfer case intermediate gear (1302) is meshed with the transfer case output gear (1305), and the transfer case output gear (1305) is connected with the transfer case front output shaft (1304) through the transfer case clutch (1303).
8. The control method of the tractor diesel-electric hybrid power system based on gear coupling according to claim 1, wherein after the tractor is normally started, the running state information of the tractor is obtained in real time, and the working modes of the diesel engine (1), the first motor (16) and the second motor (15) are determined according to the real-time loads of the rotating power and the traction power output end: When the tractor driving wheel runs and the traction power demand power is smaller than 0, controlling the second motor (15) to work in an energy recovery mode by utilizing the power transmitted by the walking transmission (14); When the tractor driving wheel runs and the traction power demand power is greater than 0, if the current state of charge (SOC) of the storage battery is greater than a set upper limit, controlling the first motor (16) or the second motor (15) to transmit power to the walking transmission (14) in a pure electric mode; If the current state of charge (SOC) of the storage battery does not exceed the set upper limit, determining a working mode according to the total power required by the tractor power system, wherein the total power required by the tractor power system is equal to the sum of the rotation power required power and the traction power required power; When the total power required by the power system is smaller than the lower limit of the total power required economic interval mechanically connected with the diesel engine, disconnecting the transmission connection between the output shaft (1011) of the first motor and the walking transmission (14), and driving the first motor (16) by the diesel engine (1) to generate electricity to supplement the electricity of the storage battery, and supplying power to the second motor (15) by the storage battery to drive the walking transmission (14); When the total power required by the power system exceeds the lower limit of the total power required economic interval of the mechanical connection of the diesel engine, the transmission connection between the output shaft (1011) of the first motor and the walking transmission (14) is established, and the diesel engine (1) is controlled to be independently driven, or the power system is driven in parallel with the second motor (15), or the power system is driven in a series-parallel manner with the first motor (16) and the second motor (15) to provide power for the walking transmission (14).
9. The control method of claim 8, wherein when there are a plurality of operating modes meeting the conditions, the switching of different modes is realized by the equivalent fuel consumption minimum strategy, and under the constraint condition of the system, the calculation formula of the equivalent fuel consumption minimum strategy is as follows: Wherein, the The actual fuel consumption rate of the diesel engine; The equivalent fuel consumption rate of the storage battery; Is an equivalent factor; The output power of the diesel engine; the output power of the storage battery; Is the low heating value of the fuel; The battery transmission efficiency is improved.

Description

Tractor diesel-electric hybrid power system based on gear coupling and control method Technical Field The invention belongs to the field of hybrid power of tractors, and particularly relates to a diesel-electric hybrid power system of a tractor based on gear coupling and a control method. Background The tractor is used as a key power machine for modern agricultural production, and the working condition of the tractor presents vivid two polarization characteristics, namely, in heavy-load field operations such as ploughing, rotary tillage and the like, high traction force is required to be continuously output, the running speed is stable and is in a low-speed interval, meanwhile, a power output shaft is relied on to provide constant rotation speed power for matched farm tools, and under light-load scenes such as field transfer, no-load transportation or road running, the load is obviously reduced, the speed fluctuation is frequent, and the transmission system is required to have stepless speed regulation capacity so as to improve the comprehensive efficiency. The traditional tractor generally adopts a power transmission framework consisting of a diesel engine, a multi-gear mechanical gearbox and a transfer case. In order to meet the contradictory working condition demands of low-speed heavy load and high-speed light load, a gearbox is often required to be provided with a complex gear mechanism, so that the system is large in structure and high in manufacturing cost, and the system is accompanied with the inherent defects of complex gear shifting operation, obvious impact feeling and the like. The current hybrid power tractor technical route mainly covers two types of serial connection and parallel connection. The series scheme can realize stepless speed change, but under the heavy load working condition, the energy needs to undergo secondary conversion from mechanical energy to electric energy to mechanical energy, the comprehensive efficiency of the system is obviously lower than that of a mechanical direct drive mode, continuous high-load traction operation is difficult to overcome, the existing simple parallel scheme mostly adopts a structure that a motor is additionally arranged at the input end of a gearbox, the technical bottleneck of strong coupling of the rotating speed of a power output shaft and the speed of the whole vehicle cannot be broken, and the integral optimization space of the system is limited because a rear axle gearbox and a mechanical front driving shaft with complex structures are reserved. Disclosure of Invention The invention aims to provide a diesel-electric hybrid power system of a tractor and a control method thereof based on gear coupling, which solve the problems of complex transmission system structure and poor operation fuel economy of the traditional tractor under complex operation working conditions, realize flexible switching of serial and parallel operation modes and accurately adapt to the operation characteristics of high load, low speed, low load and wide speed of the tractor. The invention aims to solve the technical problems, and adopts the technical scheme that the diesel-electric hybrid power system of the tractor based on gear coupling comprises a diesel engine, a first motor, a second motor, a gear coupling device, a power output speed changer and a walking speed changer, wherein the diesel engine is connected with a first motor output shaft of the first motor, and the first motor output shaft is connected with the power output speed changer to output rotary power; The first motor and the second motor are in two working states of power generation and power output, so that the first motor can be driven by the diesel engine to generate power to supplement the electric quantity of the storage battery, or the first motor output shaft is driven by the storage battery to operate, and the second motor can be driven by the storage battery to operate, or the power recovered by the walking transmission is utilized to generate power to supplement the electric quantity of the storage battery. The gear coupling device comprises a gear coupling device output shaft connected to the walking transmission, wherein a power transmission path is formed between the first motor output shaft and the gear coupling device output shaft through a gear speed change mechanism; The gear speed change mechanism is connected with the first motor output shaft through a speed change clutch, the driving gear of the second motor output shaft is connected with the second motor output shaft through a driving gear clutch of the second motor output shaft, and the first motor output shaft and the second motor output shaft can independently transmit power to the walking transmission or jointly couple to transmit power to the walking transmission by controlling the clutch state of the speed change clutch and the driving gear clutch of the second motor output shaft. The diesel engine and the first motor have