A mechanical and electrical continuously variable speed composite transmission system and control method thereof

Abstract

The present invention discloses a mechanical and electrical continuously variable composite transmission system and a control method thereof, comprising an input shaft assembly, a mechanical transmission assembly, an electric transmission assembly and an output shaft assembly, and realizing the switching of a single-flow transmission mode, a composite transmission mode and an energy recovery mode through the combined switching between a clutch and a brake; the single-flow transmission mode comprises an EVT transmission mode and a mechanical transmission mode; the composite transmission mode is an EVT and mechanical composite transmission mode. Beneficial effects: The present invention can adapt to different working conditions, improve the engine power utilization rate, and improve fuel economy; effectively reduce the gear shift shock and increase the speed ratio adjustment range; in terms of power regulation, the electric transmission assembly can effectively supplement the driving force through the energy storage device, and the EVT can also recover the energy during braking; the present invention effectively broadens the speed regulation range and can meet the requirements of a wide range of linear and nonlinear stepless speed regulation.

Description

Technical Field

[0001] The present invention relates to a transmission system and a control method thereof, and in particular to a mechanical and electrical stepless variable speed composite transmission system and a control method thereof, belonging to the technical field of variable speed transmission devices. Background Art

[0002] The automobile transmission is the core component of the automobile transmission system and one of the important evaluation indicators of vehicle performance. During the driving process of the car, the automobile transmission changes the transmission ratio between the engine and the drive wheels, so that the engine always works at its best power performance state, adapting to the different requirements for the traction force and vehicle speed of the drive wheels under different conditions such as starting, accelerating, driving and overcoming various road obstacles.

[0003] When the oil in the hydraulic mechanism of a traditional hydraulic continuously variable transmission mixes with the air, it is easy to cause vibration and noise, affecting the working performance of the system. In addition, the oil in the hydraulic mechanism is easily contaminated. Once the oil is contaminated, it will affect the reliability of the system.

[0004] The electric continuously variable transmission, or EVT, is an advanced technology developed in recent years. It provides vehicles with continuously variable speeds, making driving smoother and more comfortable. When the electric continuously variable transmission and the internal combustion engine are effectively controlled and coordinated, the fuel efficiency of the vehicle can be greatly improved. In terms of power regulation, the EVT can effectively supplement the driving force through the energy storage device without changing the power requirements of the internal combustion engine, thereby keeping the working state of the internal combustion engine unaffected by road conditions and improving the efficiency of the entire vehicle. However, when the EVT is directly connected to the output shaft, the EVT will overheat at higher speeds, so the EVT transmission mode alone cannot meet the transmission requirements of multiple working conditions. Summary of the invention

[0005] Purpose of the invention: In view of the deficiencies in the prior art, the present invention provides a mechanical and electrical continuously variable composite transmission system and a control method thereof. The present invention realizes switching of multiple modes including EVT transmission, mechanical transmission, mechanical-EVT composite transmission and energy recovery by switching clutch assemblies and brake assemblies; it can adapt to different working conditions, improve engine power utilization and improve fuel economy.

[0006] Technical solution: A mechanical and electrical stepless variable speed compound transmission system.

[0007] An input shaft assembly is included, wherein the input shaft assembly includes an input shaft, a first clutch C1 and an input gear pair;

[0008] A mechanical transmission assembly, the mechanical transmission assembly includes a mechanical transmission shaft, a front planetary gear assembly, a rear planetary gear assembly, a fifth clutch C5, a first brake B1 and a second brake B2, the front planetary gear assembly includes a front sun gear, a front planetary carrier and a front ring gear, the rear planetary gear assembly includes a rear sun gear, a rear planetary carrier and a rear ring gear; the mechanical transmission shaft is connected to the input shaft through the first clutch C1, the mechanical transmission shaft is fixedly connected to the front ring gear and the rear sun gear respectively, the front planetary carrier is connected to the rear planetary carrier, the front sun gear is connected to the mechanical transmission shaft through the fifth clutch C5, the first brake B1 can lock the front sun gear, and the second brake B2 can lock the front planetary carrier and the rear planetary carrier at the same time;

[0009] An electric transmission assembly, the electric transmission assembly comprising an electric input shaft, an inner rotor, an outer rotor, a stator, a power supply, an electric output shaft, a second clutch C2 and a third clutch C3; the input gear pair is connected to the electric input shaft through the second clutch C2, the electric input shaft is connected to the inner rotor, the electric output shaft is connected to the outer rotor, the power supply supplies power to the stator to generate a magnetic field, and the magnetic field generated by the stator controls the transmission speed ratio of the inner rotor relative to the outer rotor, thereby realizing the adjustment of the transmission speed ratio of the electric input shaft relative to the electric output shaft;

[0010] An output shaft assembly, the output shaft assembly includes an output shaft, an output sun gear, an output planetary carrier, an output ring gear, an output gear pair and a fourth clutch C4; the output sun gear is connected to the rear ring gear, the output ring gear is connected to the third clutch C3 through the output gear pair, the output planetary carrier is connected to the output shaft, and the output sun gear is connected to the output shaft through the fourth clutch C4.

[0011] The present invention switches between various modes, including EVT transmission, mechanical transmission, mechanical-EVT compound transmission and energy recovery, by switching the clutch assembly and the brake assembly; it can adapt to different working conditions, improve the engine power utilization rate and improve fuel economy; it effectively reduces the gear shift shock and increases the speed ratio adjustment range; in terms of power regulation, the electric transmission assembly can effectively supplement the driving force through the energy storage device, and the EVT can also recover the energy during braking and send it back to the energy storage device; the power-dividing mechanical-EVT compound transmission system described in the present invention has a mechanical-EVT parallel transmission mode, which effectively broadens the speed regulation range and can meet the requirements of a wide range of linear and nonlinear stepless speed regulation.

[0012] Preferably, in order to realize the recovery of braking energy and supplement the driving power at the same time, the electric transmission assembly includes a slip ring, which is connected to the inner rotor, and the inner rotor converts mechanical energy into electrical energy, and the generated electrical energy is transmitted to the power supply through the slip ring.

[0013] A control method for a mechanical and electrical continuously variable transmission system realizes switching among a single-flow transmission mode, a compound transmission mode and an energy recovery mode by combined switching between a clutch and a brake; the single-flow transmission mode includes an EVT transmission mode and a mechanical transmission mode; the compound transmission mode is an EVT and mechanical compound transmission mode.

[0014] The engagement elements of each transmission mode are shown in Table 1. The details are as follows:

[0015] Table 1 Mode switching element engagement status

[0016]

[0017] Note: ▲ represents the actuator is in the engaged state, △ represents the actuator is in the disengaged state.

[0018] Preferably, the control method of the EVT transmission mode is as follows:

[0019] The second clutch C2, the third clutch C3 and the fourth clutch C4 are engaged, while the first clutch C1, the fifth clutch C5, the first brake B1 and the second brake B2 are disengaged; the power is output from the input shaft through the input gear pair, the second clutch C2, the electric input shaft, the inner rotor, the outer rotor, the electric output shaft, the third clutch C3, the output gear pair, the output ring gear, the output planetary carrier to the output shaft.

[0020] Preferably, the mechanical transmission mode includes mechanical transmission 1st gear, mechanical transmission 2nd gear and mechanical transmission 3rd gear, and the specific control method is as follows:

[0021] Mechanical transmission 1st gear (M1): The first clutch C1, the fourth clutch C4 and the first brake B1 are engaged, while the second clutch C2, the third clutch C3, the fifth clutch C5 and the second brake B2 are disengaged; the power is transmitted from the input shaft through the first clutch C1 to the mechanical transmission shaft, and the power is divided by the mechanical transmission shaft, one route is from the front ring gear and the front planetary carrier to the rear planetary carrier, and the other route is from the rear sun gear to the rear planetary carrier. The two routes of power converge at the rear planetary carrier, and then are output from the rear ring gear and the fourth clutch C4 to the output shaft;

[0022] Mechanical transmission 2nd gear (M2): the first clutch C1, the fourth clutch C4 and the fifth clutch C5 are engaged, while the second clutch C2, the third clutch C3, the first brake B1 and the second brake B2 are disengaged; the power is transferred from the input shaft through the first clutch C1 to the mechanical transmission shaft, and the power is divided by the mechanical transmission shaft, the first route is from the fifth clutch C5 and the front sun gear to the front planetary carrier, the second route is from the front ring gear to the front planetary carrier, the first route and the second route are combined to the rear planetary carrier, the third route is from the rear sun gear to the rear planetary carrier, the power is combined to the rear planetary carrier, and then output to the output shaft through the rear ring gear and the fourth clutch C4;

[0023] Mechanical transmission 3rd gear (M3): the first clutch C1, the fourth clutch C4 and the second brake B2 are engaged, while the second clutch C2, the third clutch C3, the fifth clutch C5 and the first brake B1 are disengaged; power is output from the input shaft through the first clutch C1, the mechanical transmission shaft, the rear sun gear, the rear planetary carrier, the rear ring gear, the fourth clutch C4 to the output shaft.

[0024] Preferably, the EVT and mechanical compound transmission mode includes EVT and mechanical compound transmission 1st gear (EVT-M1), EVT and mechanical compound transmission 2nd gear (EVT-M2) and EVT and mechanical compound transmission 3rd gear (EVT-M3), and the specific control method is as follows:

[0025] EVT and mechanical compound transmission 1st gear (EVT-M1): the first clutch C1, the second clutch C2, the third clutch C3 and the first brake B1 are engaged, while the fourth clutch C4, the fifth clutch C5 and the second brake B2 are disengaged;

[0026] The power is split from the input shaft, passing through the input gear pair, the second clutch C2, the electric input shaft, the inner rotor, the outer rotor, the electric output shaft, the third clutch C3, the output gear pair, the output ring gear to the output planet carrier;

[0027] The other power passes through the first clutch C1 to the mechanical transmission shaft, and the power is split by the mechanical transmission shaft, one way is from the front ring gear and the front planetary carrier to the rear planetary carrier, and the other way is from the rear sun gear to the rear planetary carrier. The two power flows merge at the rear planetary carrier, and then from the rear ring gear and the output sun gear to the output planetary carrier. After passing through the mechanical transmission component and the electric transmission component, the power merges at the output planetary carrier and is output from the output shaft;

[0028] EVT and mechanical compound transmission 2nd gear (EVT-M2): the first clutch C1, the second clutch C2, the third clutch C3 and the fifth clutch C5 are engaged, while the fourth clutch C4, the first brake B1 and the second brake B2 are disengaged;

[0029] The power is split from the input shaft, passing through the input gear pair, the second clutch C2, the electric input shaft, the inner rotor, the outer rotor, the electric output shaft, the third clutch C3, the output gear pair, the output ring gear to the output planet carrier;

[0030] Another power path is from the input shaft through the first clutch C1 to the mechanical transmission shaft, and the power is divided by the mechanical transmission shaft. The first path is from the fifth clutch C5 and the front sun gear to the front planetary carrier, and the second path is from the front ring gear to the front planetary carrier. The first and second paths are combined to the rear planetary carrier, and the third path is from the rear sun gear to the rear planetary carrier. The power is combined with the rear planetary carrier, and then from the rear ring gear and the output sun gear to the output planetary carrier. After passing through the mechanical transmission component and the electric transmission component, the power is combined with the output planetary carrier and then output from the output shaft;

[0031] EVT and mechanical compound transmission 3rd gear (EVT-M3): the first clutch C1, the second clutch C2, the third clutch C3 and the second brake B2 are engaged, while the fourth clutch C4, the fifth clutch C5 and the first brake B1 are disengaged;

[0032] The power is split from the input shaft, passing through the input gear pair, the second clutch C2, the electric input shaft, the inner rotor, the outer rotor, the electric output shaft, the third clutch C3, the output gear pair, the output ring gear to the output planet carrier;

[0033] The other power is from the input shaft through the first clutch C1, the fourth clutch C4 and the second brake B2, while the second clutch C2, the third clutch C3, the fifth clutch C5 and the first brake B1 are separated; the power is from the input shaft through the first clutch C1, the mechanical transmission shaft, the rear sun gear, the rear planetary carrier, the rear ring gear, the output sun gear to the output planetary carrier, and the power of the mechanical transmission component and the electric transmission component is combined with the output planetary carrier and then output by the output shaft.

[0034] Preferably, the control method of the energy recovery mode is as follows:

[0035] The third clutch C3, the first brake B1 and the second brake B2 are engaged, while the first clutch C1, the second clutch C2, the fourth clutch C4 and the fifth clutch C5 are disengaged; the braking force is transmitted from the output shaft through the output planetary carrier, the output ring gear, the output gear pair, the third clutch C3, the electric output shaft to the outer rotor, the outer rotor converts mechanical energy into electrical energy and transmits it to the power supply through the stator, and the power supply stores the recovered energy in the form of electrical energy.

[0036] Preferably, when EVT is in transmission, the power is driven by the electric input shaft to drive the inner rotor to rotate, a part of the mechanical energy is converted into electrical energy through the slip ring and transmitted to the power supply, the power supply is converted into mechanical energy through the stator and the outer rotor and output by the electric output shaft; the other part of the mechanical energy is directly converted into mechanical energy through the electromagnetic field coupling between the stator and the outer rotor and output by the electric output shaft.

[0037] Preferably, the method for calculating the output shaft speed of the single-flow transmission mode is as follows:

[0038] EVT transmission mode:

[0039]

[0040] Where n0(EVT) is the output shaft speed in EVT transmission mode, n I is the input shaft speed, i1 is the transmission ratio of the input gear pair, i2 is the transmission ratio of the output gear pair, and i2 is the transmission ratio of the electric drive assembly;

[0041] Mechanical transmission 1st gear (M1):

[0042]

[0043] Where n O (M1) is the output shaft speed when the mechanical transmission is in the first gear, n I is the input shaft speed, k1 is the characteristic parameter of the planetary gear of the front planetary gear assembly, and k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly;

[0044] Mechanical transmission 2nd gear (M2):

[0045] n o (M2) = n I

[0046] Where n O (M2) is the output shaft speed when the mechanical transmission is in the second gear, n I is the input shaft speed;

[0047] Mechanical transmission 3rd gear (M3):

[0048]

[0049] Where n O (M3) is the output shaft speed when the mechanical transmission is in the third gear, n I The input shaft speed k2 is the planetary gear characteristic parameter of the rear planetary gear assembly.

[0050] Preferably, the output shaft speed calculation method of the EVT and mechanical compound transmission 1st gear (EVT-M1), EVT and mechanical compound transmission 2nd gear (EVT-M2) and EVT and mechanical compound transmission 3rd gear (EVT-M3) is as follows:

[0051] EVT and mechanical compound transmission 1st gear (EVT-M1):

[0052]

[0053] Where n O (EVT-M1) is the output shaft speed when the EVT and mechanical compound transmission are in the first gear, n I is the input shaft speed, i1 is the transmission ratio of the input gear pair, i2 is the transmission ratio of the output gear pair, ie is the transmission ratio of the electric transmission assembly, k1 is the characteristic parameter of the planetary gear of the front planetary gear assembly, k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly, and k3 is the characteristic parameter of the planetary gear of the output shaft assembly;

[0054] EVT and mechanical compound transmission 2 gears (EVT-M2):

[0055]

[0056] Where n O (EVT-M2) is the output shaft speed when the EVT and mechanical compound transmission are in the second gear, n I is the input shaft speed, i1 is the transmission ratio of the input gear pair, i2 is the transmission ratio of the output gear pair, i2 is the transmission ratio of the electric transmission assembly, and k3 is the characteristic parameter of the planetary gear of the output shaft assembly;

[0057] EVT and mechanical compound transmission 3 gears (EVT-M3):

[0058]

[0059] Where n O (EVT-M3) is the output shaft speed when the EVT and mechanical compound transmission are in the third gear, n I is the input shaft speed, i1 is the transmission ratio of the input gear pair, i2 is the transmission ratio of the output gear pair, i2 is the transmission ratio of the electric transmission assembly, k2 is the planetary gear characteristic parameter of the rear planetary row assembly, and k3 is the planetary gear characteristic parameter of the output shaft assembly.

[0060] Beneficial effects: The present invention realizes switching of multiple modes including EVT transmission, mechanical transmission, mechanical-EVT compound transmission and energy recovery by switching the clutch assembly and the brake assembly; it can adapt to different working conditions, improve the engine power utilization rate and improve fuel economy; it effectively reduces the gear shift shock and increases the speed ratio adjustment range; in terms of power regulation, the electric transmission assembly can effectively supplement the driving force through the energy storage device, and the EVT can also recover the energy during braking and send it back to the energy storage device; the power-dividing mechanical-EVT compound transmission system described in the present invention and the mechanical-EVT parallel transmission mode set up effectively broaden the speed regulation range and can meet the requirements of a wide range of linear and nonlinear stepless speed regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative work.

[0062] Figure 1 It is a structural principle diagram of the present invention;

[0063] Figure 2 It is a schematic diagram of power flow in the EVT transmission mode of the present invention;

[0064] Figure 3 It is a schematic diagram of power flow of the first gear of the mechanical transmission of the present invention;

[0065] Figure 4 It is a schematic diagram of the power flow of the second gear of the mechanical transmission of the present invention;

[0066] Figure 5 It is a schematic diagram of power flow of the third gear of the mechanical transmission of the present invention;

[0067] Figure 6 It is a schematic diagram of the power flow of the EVT and mechanical compound transmission 1st gear of the present invention;

[0068] Figure 7 It is a schematic diagram of the power flow of the EVT and the mechanical compound transmission 2nd gear of the present invention;

[0069] Figure 8 It is a schematic diagram of the power flow of the EVT and mechanical compound transmission 3rd gear of the present invention;

[0070] Fig. 9 This is a schematic diagram of power flow in the energy recovery mode of the present invention;

[0071] Fig.10 Schematic diagram of power flow in the EVT transmission mode of the present invention

[0072] Fig.11 It is a characteristic curve diagram of the relationship between the output speed and the input speed of the present invention. DETAILED DESCRIPTION

[0073] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0075] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0076] like Figure 1 As shown, a mechanical and electrical continuously variable composite transmission system,

[0077] It includes an input shaft assembly, wherein the input shaft assembly 1 includes an input shaft 11, a first clutch C112 and an input gear pair 13;

[0078] A mechanical transmission assembly 2, the mechanical transmission assembly 2 comprises a mechanical transmission shaft 21, a front planetary row assembly 22, a rear planetary row assembly 23, a fifth clutch C524, a first brake B125 and a second brake B226, the front planetary row assembly 22 comprises a front sun gear 221, a front planetary carrier 222 and a front ring gear 223, the rear planetary row assembly 23 comprises a rear sun gear 231, a rear planetary carrier 232 and a rear ring gear 233; the mechanical transmission shaft 21 is connected to the input shaft 11 through the first clutch C112, the mechanical transmission shaft 21 is fixedly connected to the front ring gear 223 and the rear sun gear 231 respectively, the front planetary carrier 222 is connected to the rear planetary carrier 232, the front sun gear 221 is connected to the mechanical transmission shaft 21 through the fifth clutch C524, the first brake B125 can lock the front sun gear 221, and the second brake B226 can simultaneously lock the front planetary carrier 222 and the rear planetary carrier 232;

[0079] The electric transmission assembly 3 includes an electric input shaft 31, an inner rotor 32, an outer rotor 33, a stator 34, a power supply 35, an electric output shaft 36, a second clutch C237 and a third clutch C338; the input gear pair 13 is connected to the electric input shaft 31 through the second clutch C237, the electric input shaft 31 is connected to the inner rotor 32, the electric output shaft 36 is connected to the outer rotor 33, the power supply 35 supplies power to the stator 34 to generate a magnetic field, and the magnetic field generated by the stator 34 controls the transmission speed ratio of the inner rotor 32 relative to the outer rotor 33, so as to adjust the transmission speed ratio of the electric input shaft 31 relative to the electric output shaft 36;

[0080] The output shaft assembly 4 comprises an output shaft 41, an output sun gear 42, an output planetary carrier 43, an output ring gear 44, an output gear pair 45 and a fourth clutch C446; the output sun gear 42 is connected to the rear ring gear 233, the output ring gear 44 is connected to the third clutch C338 via the output gear pair 45, the output planetary carrier 43 is connected to the output shaft 41, and the output sun gear 42 is connected to the output shaft 41 via the fourth clutch C446.

[0081] The present invention switches between various modes, including EVT transmission, mechanical transmission, mechanical-EVT compound transmission and energy recovery, by switching the clutch assembly and the brake assembly; it can adapt to different working conditions, improve the engine power utilization rate and improve fuel economy; it effectively reduces the gear shift shock and increases the speed ratio adjustment range; in terms of power regulation, the electric transmission assembly can effectively supplement the driving force through the energy storage device, and the EVT can also recover the energy during braking and send it back to the energy storage device; the power-dividing mechanical-EVT compound transmission system described in the present invention has a mechanical-EVT parallel transmission mode, which effectively broadens the speed regulation range and can meet the requirements of a wide range of linear and nonlinear stepless speed regulation.

[0082] In order to recover braking energy and supplement driving power at the same time, the electric transmission assembly 3 includes a slip ring 39, which is connected to the inner rotor 32. The inner rotor 32 converts mechanical energy into electrical energy, and the generated electrical energy is transmitted to the power supply 35 through the slip ring 39.

[0083] A control method for a mechanical and electrical continuously variable transmission system realizes switching among a single-flow transmission mode, a compound transmission mode and an energy recovery mode by combined switching between a clutch and a brake; the single-flow transmission mode includes an EVT transmission mode and a mechanical transmission mode; the compound transmission mode is an EVT and mechanical compound transmission mode.

[0084] The engagement elements of each transmission mode are shown in Table 1. The details are as follows:

[0085] Table 1 Mode switching element engagement status

[0086]

[0087] Note: ▲ represents the actuator is in the engaged state, △ represents the actuator is in the disengaged state.

[0088] like Figure 2 As shown, the control method of the EVT transmission mode is as follows:

[0089] The second clutch C237, the third clutch C338 and the fourth clutch C446 are engaged, while the first clutch C112, the fifth clutch C524, the first brake B125 and the second brake B226 are disengaged; the power is output from the input shaft 11 through the input gear pair 13, the second clutch C237, the electric input shaft 31, the inner rotor 32, the outer rotor 33, the electric output shaft 36, the third clutch C338, the output gear pair 45, the output ring gear 44, the output planetary carrier 43 to the output shaft 41.

[0090] The method for calculating the speed of the output shaft 41 in the EVT transmission mode is as follows:

[0091]

[0092] Wherein, n0(EVT) is the speed of the output shaft 41 in the EVT transmission mode, n I is the speed of the input shaft 11, i1 is the transmission ratio of the input gear pair 13, i2 is the transmission ratio of the output gear pair 45, i e is the transmission ratio of the electric transmission assembly 3.

[0093] like Figure 3 As shown, the control method of mechanical transmission 1st gear (M1) is as follows:

[0094] The first clutch C112, the fourth clutch C446 and the first brake B125 are engaged, while the second clutch C237, the third clutch C338, the fifth clutch C524 and the second brake B226 are disengaged; the power is transmitted from the input shaft 11 through the first clutch C112 to the mechanical transmission shaft 21, and the power is divided by the mechanical transmission shaft 21, one route is the front ring gear 223 and the front planetary carrier 222 to the rear planetary carrier 232, and the other route is the rear sun gear 231 to the rear planetary carrier 232, and the two routes of power converge at the rear planetary carrier 232, and then output from the rear ring gear 233 and the fourth clutch C446 to the output shaft 41;

[0095] The method for calculating the speed of the output shaft 41 of the mechanical transmission 1st gear (M1) is as follows:

[0096]

[0097] Where n O(M1) is the output shaft speed of the mechanical transmission in the first gear, n I is the rotation speed of the input shaft 11 , k1 is the characteristic parameter of the planetary gear of the front planetary gear assembly 22 , and k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly 23 .

[0098] like Figure 4 As shown, the control method of mechanical transmission 2nd gear (M2) is as follows:

[0099] The first clutch C112, the fourth clutch C446 and the fifth clutch C524 are engaged, while the second clutch C237, the third clutch C338, the first brake B125 and the second brake B226 are disengaged; the power is transmitted from the input shaft 11 through the first clutch C112 to the mechanical transmission shaft 21, and the power is divided by the mechanical transmission shaft 21, the first route is from the fifth clutch C524 and the front sun gear 221 to the front planetary carrier 222, the second route is from the front ring gear 223 to the front planetary carrier 222, the first route and the second route are combined to the rear planetary carrier 232, the third route is from the rear sun gear 231 to the rear planetary carrier 232, the power is combined to the rear planetary carrier 232, and then outputted from the rear ring gear 233 and the fourth clutch C446 to the output shaft 41;

[0100] The method for calculating the speed of the output shaft 41 of the mechanical transmission 2nd gear (M2) is as follows:

[0101] n o (M2) = n I

[0102] Where n O (M2) is the output shaft 41 speed when the mechanical transmission is in the second gear, n I is the speed of input shaft 11.

[0103] like Figure 5 As shown, the control method of mechanical transmission 3rd gear (M3) is as follows:

[0104] The first clutch C112, the fourth clutch C446 and the second brake B226 are engaged, while the second clutch C237, the third clutch C338, the fifth clutch C524 and the first brake B125 are disengaged; power is output from the input shaft 11 through the first clutch C112, the mechanical transmission shaft 21, the rear sun gear 231, the rear planetary carrier 232, the rear ring gear 233, the fourth clutch C446 to the output shaft 41.

[0105] The method for calculating the speed of the output shaft 41 of the mechanical transmission 3rd gear (M3) is as follows:

[0106]

[0107] Where n O (M3) is the output shaft 41 speed when the mechanical transmission is in the third gear, nI The rotation speed k2 of the input shaft 11 is the planetary gear characteristic parameter of the rear planetary gear assembly 23 .

[0108] like Figure 6 As shown, the control method of EVT and mechanical compound transmission 1st gear (EVT-M1) is as follows:

[0109] The first clutch C112, the second clutch C237, the third clutch C338 and the first brake B125 are engaged, while the fourth clutch C446, the fifth clutch C524 and the second brake B226 are disengaged;

[0110] The power is divided by the input shaft 11, passing through the input gear pair 13, the second clutch C237, the electric input shaft 31, the inner rotor 32, the outer rotor 33, the electric output shaft 36, the third clutch C338, the output gear pair 45, the output ring gear 44 to the output planet carrier 43;

[0111] The other power passes through the first clutch C112 to the mechanical transmission shaft 21, and the power is divided by the mechanical transmission shaft 21, one way is from the front ring gear 223 and the front planetary carrier 222 to the rear planetary carrier 232, and the other way is from the rear sun gear 231 to the rear planetary carrier 232. The two power flows converge at the rear planetary carrier 232, and then from the rear ring gear 233 and the output sun gear 42 to the output planetary carrier 43. After passing through the mechanical transmission component 2 and the electric transmission component 3, the power converges at the output planetary carrier 43 and is output from the output shaft 41.

[0112] The calculation method of the output shaft 41 speed of EVT and mechanical compound transmission 1st gear (EVT-M1) is as follows:

[0113]

[0114] Where n O (EVT-M1) is the output shaft speed of EVT and mechanical compound transmission in 1st gear, n I is the speed of the input shaft 11, i1 is the transmission ratio of the input gear pair 13, i2 is the transmission ratio of the output gear pair 45, i2 is the transmission ratio of the electric transmission assembly 3, k1 is the planetary gear characteristic parameter of the front planetary gear assembly 22, k2 is the planetary gear characteristic parameter of the rear planetary gear assembly 23, and k3 is the planetary gear characteristic parameter of the output shaft assembly 4.

[0115] like Figure 7 As shown, the control method of EVT and mechanical compound transmission 2 (EVT-M2) is as follows:

[0116] The first clutch C112, the second clutch C237, the third clutch C338 and the fifth clutch C524 are engaged, while the fourth clutch C446, the first brake B125 and the second brake B226 are disengaged;

[0117] The power is divided by the input shaft 11, passing through the input gear pair 13, the second clutch C237, the electric input shaft 31, the inner rotor 32, the outer rotor 33, the electric output shaft 36, the third clutch C338, the output gear pair 45, the output ring gear 44 to the output planet carrier 43;

[0118] Another power route is from the input shaft 11 to the mechanical transmission shaft 21 through the first clutch C112. The power is divided from the mechanical transmission shaft 21. The first route is from the fifth clutch C524 and the front sun gear 221 to the front planetary carrier 222. The second route is from the front ring gear 223 to the front planetary carrier 222. The first and second routes are combined to reach the rear planetary carrier 232. The third route is from the rear sun gear 231 to the rear planetary carrier 232. The power is combined with the rear planetary carrier 232, and then from the rear ring gear 233 and the output sun gear 42 to the output planetary carrier 43. After passing through the mechanical transmission component 2 and the electric transmission component 3, the power is combined with the output planetary carrier 43 and then output from the output shaft 41.

[0119] The calculation method of the output shaft 41 speed of EVT and mechanical compound transmission 2nd gear (EVT-M2) is as follows:

[0120]

[0121] Where n O (EVT-M2) is the output shaft speed 41 when the EVT and mechanical compound transmission are in 2nd gear, n I is the speed of the input shaft 11 , i1 is the transmission ratio of the input gear pair 13 , i2 is the transmission ratio of the output gear pair 45 , i2 is the transmission ratio of the electric transmission assembly 3 , and k3 is the characteristic parameter of the planetary gear of the output shaft assembly 4 .

[0122] like Figure 8 As shown, the control method of EVT and mechanical compound transmission 3 (EVT-M3) is as follows:

[0123] The first clutch C112, the second clutch C237, the third clutch C338 and the second brake B226 are engaged, while the fourth clutch C446, the fifth clutch C524 and the first brake B125 are disengaged;

[0124] The power is divided by the input shaft 11, passing through the input gear pair 13, the second clutch C237, the electric input shaft 31, the inner rotor 32, the outer rotor 33, the electric output shaft 36, the third clutch C338, the output gear pair 45, the output ring gear 44 to the output planet carrier 43;

[0125] Another power is from the input shaft 11 through the first clutch C112, the fourth clutch C446 and the second brake B226 to engage, while the second clutch C237, the third clutch C338, the fifth clutch C524 and the first brake B125 are separated; the power is from the input shaft 11 through the first clutch C112, the mechanical transmission shaft 21, the rear sun gear 231, the rear planetary carrier 232, the rear ring gear 233, the output sun gear 42 to the output planetary carrier 43, and the power of the mechanical transmission component 2 and the electric transmission component 3 is merged with the output planetary carrier 43 and then output by the output shaft 41.

[0126] The calculation method of the output shaft 41 speed of EVT and mechanical compound transmission 3rd gear (EVT-M3) is as follows:

[0127]

[0128] Where n O (EVT-M3) is the output shaft speed 41 when the EVT and mechanical compound transmission are in the third gear, n I is the speed of the input shaft 11, i1 is the transmission ratio of the input gear pair 13, i2 is the transmission ratio of the output gear pair 45, i e is the transmission ratio of the electric transmission assembly 3 , k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly 23 , and k3 is the characteristic parameter of the planetary gear of the output shaft assembly 4 .

[0129] like Fig. 9 As shown, the control method of the energy recovery mode is as follows:

[0130] The third clutch C338, the first brake B125 and the second brake B226 are engaged, while the first clutch C112, the second clutch C237, the fourth clutch C446 and the fifth clutch C524 are disengaged; the braking force is transmitted from the output shaft 41 through the output planetary carrier 43, the output ring gear 44, the output gear pair 45, the third clutch C338, the electric output shaft 36 to the outer rotor 33, the outer rotor 33 converts mechanical energy into electrical energy and transmits it to the power supply 35 from the stator 34, and the power supply 35 stores the recovered energy in the form of electrical energy.

[0131] like Fig.10 As shown, when the EVT is in transmission, the power is driven by the electric input shaft 31 to drive the inner rotor 32 to rotate, and a part of the mechanical energy is converted into electrical energy through the slip ring 39 and transmitted to the power supply 35. The power supply 35 is converted into mechanical energy through the stator 34 and the outer rotor 33 and output by the electric output shaft 36; the other part of the mechanical energy is directly converted into mechanical energy through the electromagnetic field coupling between the stator 34 and the outer rotor 33 and output by the electric output shaft 36.

[0132] like Fig.11As shown, by adjusting the transmission ratio of the EVT transmission assembly and selectively controlling the engagement of the clutch assembly and the brake assembly, four transmission modes are provided: EVT transmission, EVT-M1 compound transmission, EVT-M2 compound transmission and EVT-M3 compound transmission. When starting in the EVT transmission mode, the output speed changes with the transmission ratio of the EVT transmission assembly. e Increase linearly; when the transmission ratio of the EVT transmission component i e ∈[n o (EVT) = n o (EVT-M3)], the EVT transmission mode can be synchronously switched to the EVT-M3 compound transmission mode. When the transmission ratio of the EVT transmission component changes from the minimum value to the maximum value, n o (EVT-M3) increases nonlinearly; using the EVT-M2 transmission mode, the starting output speed increases with the transmission ratio of the EVT transmission component. e Increase nonlinearly; use EVT-M2 transmission mode to increase the output speed with the transmission ratio of the EVT transmission component i e By selectively controlling the engagement of the clutch assembly and the brake assembly, three transmission modes of mechanical transmission M1, M2 and M3 are provided, and three different fixed ratio mechanical transmission modes can be obtained.

[0133] For example:

[0134] The main parameters are: i1 = 0.51, i2 = 0.5, k1 = 1.86, k2 = 1.5, k3 = 1.72, i e ∈[0, 3.5]

[0135] The relationship between EVT transmission output and input speed is:

[0136] The output-input speed relationship of mechanical transmission M1 is:

[0137] The output-input speed relationship of mechanical transmission M2 is: n o (M2) = n I

[0138] The output-input speed relationship of mechanical transmission M3 is:

[0139] The output-input speed relationship of EVT-mechanical compound transmission EVT-M1 is:

[0140]

[0141] The output-input speed relationship of EVT-mechanical compound transmission EVT-M1 is:

[0142]

[0143] The output-input speed relationship of EVT-mechanical compound transmission EVT-M1 is:

[0144]

[0145] like Fig.11 As shown, the EVT transmission mode is adopted to start. When the transmission ratio of the EVT transmission mechanism is i e When n changes from 0 to 3.5, o (EVT) increases linearly from 0 to 3.43n I ; When the transmission ratio of the EVT transmission mechanism is i e =2.4, the EVT transmission mode can be synchronously switched to the EVT-mechanical compound transmission EVT-M3 mode, which is a nonlinear transmission; the EVT-mechanical compound transmission EVT-M2 mode is used for starting. In this mode, when the transmission ratio i of the EVT transmission mechanism is e When n changes from 0 to 3.5, o Nonlinearly increases from 0 to 0.86n I ; In EVT-mechanical compound transmission EVT-M1 mode, when the transmission ratio of the EVT transmission mechanism is i e When n changes from 0 to 3.5, o Linearly from 2.68n I Increased to 4.19n I By selectively controlling the engagement of the clutch assembly and the brake assembly, three transmission modes of mechanical transmission M1, M2 and M3 are provided, and three different fixed ratio mechanical transmission modes can be obtained, which are n o (M1)=1.08n I 、n o (M2) = 1n I and n o (M3) = 0.67n I .

[0146] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0147] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a mechanical and electrical continuously variable transmission system, characterized in that: The compound transmission system comprises an input shaft assembly (1), wherein the input shaft assembly (1) comprises an input shaft (11), a first clutch C1 (12) and an input gear pair (13); A mechanical transmission assembly (2), the mechanical transmission assembly (2) comprising a mechanical transmission shaft (21), a front planetary gear assembly (22), a rear planetary gear assembly (23), a fifth clutch C5 (24), a first brake B1 (25) and a second brake B2 (26), the front planetary gear assembly (22) comprising a front sun gear (221), a front planetary carrier (222) and a front ring gear (223), the rear planetary gear assembly (23) comprising a rear sun gear (231), a rear planetary carrier (232) and a rear ring gear (233); the mechanical transmission shaft (21) The first clutch C1 (12) is connected to the input shaft (11), the mechanical transmission shaft (21) is fixedly connected to the front ring gear (223) and the rear sun gear (231) respectively, the front planet carrier (222) is connected to the rear planet carrier (232), the front sun gear (221) is connected to the mechanical transmission shaft (21) through the fifth clutch C5 (24), the first brake B1 (25) can lock the front sun gear (221), and the second brake B2 (26) can lock the front planet carrier (222) and the rear planet carrier (232) at the same time; An electric transmission assembly (3), the electric transmission assembly (3) comprising an electric input shaft (31), an inner rotor (32), an outer rotor (33), a stator (34), a power source (35), an electric output shaft (36), a second clutch C2 (37) and a third clutch C3 (38); the input gear pair (13) is connected to the electric input shaft (31) via the second clutch C2 (37), the electric input shaft (31) is connected to the inner rotor (32), the electric output shaft (36) is connected to the outer rotor (33), the power source (35) supplies power to the stator (34) to generate a magnetic field, and the magnetic field generated by the stator (34) controls the transmission speed ratio of the inner rotor (32) relative to the outer rotor (33), thereby realizing the adjustment of the transmission speed ratio of the electric input shaft (31) relative to the electric output shaft (36); An output shaft assembly (4), the output shaft assembly (4) comprising an output shaft (41), an output sun gear (42), an output planetary carrier (43), an output ring gear (44), an output gear pair (45) and a fourth clutch C4 (46); the output sun gear (42) is connected to the rear ring gear (233), the output ring gear (44) is connected to the third clutch C3 (38) via the output gear pair (45), the output planetary carrier (43) is connected to the output shaft (41), and the output sun gear (42) is connected to the output shaft (41) via the fourth clutch C4 (46); The electric transmission assembly (3) comprises a slip ring (39), wherein the slip ring (39) is connected to the inner rotor (32), and the inner rotor (32) converts mechanical energy into electrical energy, and the generated electrical energy is transmitted to the power source (35) through the slip ring (39); Control method: switching between single-flow transmission mode, compound transmission mode and energy recovery mode is achieved by combined switching between clutch and brake; the single-flow transmission mode includes EVT transmission mode and mechanical transmission mode; the compound transmission mode is EVT and mechanical compound transmission mode; The EVT and mechanical compound transmission modes include EVT and mechanical compound transmission 1st gear (EVT-M1), EVT and mechanical compound transmission 2nd gear (EVT-M2) and EVT and mechanical compound transmission 3rd gear (EVT-M3), and the specific control method is as follows: EVT and mechanical compound transmission 1st gear (EVT-M1): the first clutch C1 (12), the second clutch C2 (37), the third clutch C3 (38) and the first brake B1 (25) are engaged, while the fourth clutch C4 (46), the fifth clutch C5 (24) and the second brake B2 (26) are disengaged; The power is divided from the input shaft (11), passes through the input gear pair (13), the second clutch C2 (37), the electric input shaft (31), the inner rotor (32), the outer rotor (33), the electric output shaft (36), the third clutch C3 (38), the output gear pair (45), the output ring gear (44) to the output planetary carrier (43); Another power path passes through the first clutch C1 (12) to the mechanical transmission shaft (21), and the power is divided by the mechanical transmission shaft (21), one path is from the front ring gear (223) and the front planetary carrier (222) to the rear planetary carrier (232), and the other path is from the rear sun gear (231) to the rear planetary carrier (232), the two power paths are merged at the rear planetary carrier (232), and then from the rear ring gear (233) and the output sun gear (42) to the output planetary carrier (43), and then the power of the mechanical transmission component (2) and the electric transmission component (3) is merged at the output planetary carrier (43) and output from the output shaft (41); EVT and mechanical compound transmission 2nd gear (EVT-M2): the first clutch C1 (12), the second clutch C2 (37), the third clutch C3 (38) and the fifth clutch C5 (24) are engaged, while the fourth clutch C4 (46), the first brake B1 (25) and the second brake B2 (26) are disengaged; The power is divided from the input shaft (11), passes through the input gear pair (13), the second clutch C2 (37), the electric input shaft (31), the inner rotor (32), the outer rotor (33), the electric output shaft (36), the third clutch C3 (38), the output gear pair (45), the output ring gear (44) to the output planetary carrier (43); Another power path is from the input shaft (11) through the first clutch C1 (12) to the mechanical transmission shaft (21), and the power is divided from the mechanical transmission shaft (21). The first path is from the fifth clutch C5 (24) and the front sun gear (221) to the front planetary carrier (222), and the second path is from the front ring gear (223) to the front planetary carrier (222). The first and second paths of power are combined to reach the rear planetary carrier (232), and the third path is from the rear sun gear (231) to the rear planetary carrier (232). The power is combined with the rear planetary carrier (232), and then from the rear ring gear (233) and the output sun gear (42) to the output planetary carrier (43). After passing through the mechanical transmission component (2) and the electric transmission component (3), the power is combined with the output planetary carrier (43) and then output from the output shaft (41); EVT and mechanical compound transmission 3rd gear (EVT-M3): the first clutch C1 (12), the second clutch C2 (37), the third clutch C3 (38) and the second brake B2 (26) are engaged, while the fourth clutch C4 (46), the fifth clutch C5 (24) and the first brake B1 (25) are disengaged; The power is divided from the input shaft (11), passes through the input gear pair (13), the second clutch C2 (37), the electric input shaft (31), the inner rotor (32), the outer rotor (33), the electric output shaft (36), the third clutch C3 (38), the output gear pair (45), the output ring gear (44) to the output planetary carrier (43); Another power path is transmitted from the input shaft (11) through the first clutch C1 (12), the fourth clutch C4 (46) and the second brake B2 (26) to engage, while the second clutch C2 (37), the third clutch C3 (38), the fifth clutch C5 (24) and the first brake B1 (25) are separated; the power is transmitted from the input shaft (11) through the first clutch C1 (12), the mechanical transmission shaft (21), the rear sun gear (231), the rear planetary carrier (232), the rear ring gear (233), the output sun gear (42) to the output planetary carrier (43), and then the power is transmitted through the mechanical transmission component (2) and the electric transmission component (3) to the output planetary carrier (43) and then output from the output shaft (41).

2. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 1, characterized in that: The control method of the EVT transmission mode is as follows: The second clutch C2 (37), the third clutch C3 (38) and the fourth clutch C4 (46) are engaged, while the first clutch C1 (12), the fifth clutch C5 (24), the first brake B1 (25) and the second brake B2 (26) are disengaged; power is output from the input shaft (11) through the input gear pair (13), the second clutch C2 (37), the electric input shaft (31), the inner rotor (32), the outer rotor (33), the electric output shaft (36), the third clutch C3 (38), the output gear pair (45), the output ring gear (44), the output planetary carrier (43) to the output shaft (41).

3. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 1, characterized in that: The mechanical transmission mode includes mechanical transmission 1st gear, mechanical transmission 2nd gear and mechanical transmission 3rd gear, and the specific control method is as follows: Mechanical transmission 1st gear (M1): the first clutch C1 (12), the fourth clutch C4 (46) and the first brake B1 (25) are engaged, while the second clutch C2 (37), the third clutch C3 (38), the fifth clutch C5 (24) and the second brake B2 (26) are disengaged; power is transmitted from the input shaft (11) through the first clutch C1 (12) to the mechanical transmission shaft (21), and the power is divided by the mechanical transmission shaft (21), one route is from the front ring gear (223) and the front planetary carrier (222) to the rear planetary carrier (232), and the other route is from the rear sun gear (231) to the rear planetary carrier (232), and the two routes of power converge at the rear planetary carrier (232), and then output from the rear ring gear (233) and the fourth clutch C4 (46) to the output shaft (41); Mechanical transmission 2nd gear (M2): the first clutch C1 (12), the fourth clutch C4 (46) and the fifth clutch C5 (24) are engaged, while the second clutch C2 (37), the third clutch C3 (38), the first brake B1 (25) and the second brake B2 (26) are disengaged; power is transmitted from the input shaft (11) through the first clutch C1 (12) to the mechanical transmission shaft (21), and the power is divided by the mechanical transmission shaft (21), the first route is from the fifth clutch C5 (24) and the front sun gear (221) to the front planetary carrier (222), the second route is from the front ring gear (223) to the front planetary carrier (222), the first route and the second route are combined to the rear planetary carrier (232), the third route is from the rear sun gear (231) to the rear planetary carrier (232), the power is combined to the rear planetary carrier (232), and then outputted from the rear ring gear (233) and the fourth clutch C4 (46) to the output shaft (41); Mechanical transmission 3rd gear (M3): the first clutch C1 (12), the fourth clutch C4 (46) and the second brake B2 (26) are engaged, while the second clutch C2 (37), the third clutch C3 (38), the fifth clutch C5 (24) and the first brake B1 (25) are disengaged; power is output from the input shaft (11) through the first clutch C1 (12), the mechanical transmission shaft (21), the rear sun gear (231), the rear planetary carrier (232), the rear ring gear (233), the fourth clutch C4 (46) to the output shaft (41).

4. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 1, characterized in that: The control method of energy recovery mode is as follows: The third clutch C3 (38), the first brake B1 (25) and the second brake B2 (26) are engaged, while the first clutch C1 (12), the second clutch C2 (37), the fourth clutch C4 (46) and the fifth clutch C5 (24) are disengaged; the braking force is transmitted from the output shaft (41) to the output planetary carrier (43), the output ring gear (44), the output gear pair (45), the third clutch C3 (38), the electric output shaft (36) to the outer rotor (33); the outer rotor (33) converts mechanical energy into electrical energy and transmits it to the power supply (35) through the stator (34); the power supply (35) stores the recovered energy in the form of electrical energy.

5. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 1 or 2, characterized in that: During EVT transmission, the power is driven by the electric input shaft (31) to drive the inner rotor (32) to rotate, a part of the mechanical energy is converted into electrical energy through the slip ring (39) and transmitted to the power supply (35), and the power supply (35) is converted into mechanical energy through the stator (34) and the outer rotor (33) and output by the electric output shaft (36); the other part of the mechanical energy is directly converted into mechanical energy through the electromagnetic field coupling between the stator (34) and the outer rotor (33) and output by the electric output shaft (36).

6. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 2 or 3, characterized in that: The method for calculating the rotation speed of the output shaft (41) in the single-flow transmission mode is as follows: EVT transmission mode: Where n0(EVT) is the speed of the output shaft (41) in the EVT transmission mode, n I is the speed of the input shaft (11), i1 is the transmission ratio of the input gear pair (13), i2 is the transmission ratio of the output gear pair (45), i e is the transmission ratio of the electric transmission assembly (3); Mechanical transmission 1st gear (M1): Where n o (M1) is the speed of the output shaft (41) when the mechanical transmission is in the first gear, n I is the rotation speed of the input shaft (11), k1 is the characteristic parameter of the planetary gear of the front planetary gear assembly (22), and k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly (23); Mechanical transmission 2nd gear (M2): n o (M2)=n I Where n o (M2) is the speed of the output shaft (41) when the mechanical transmission is in the second gear, n I is the speed of the input shaft (11); Mechanical transmission 3rd gear (M3): Where n o (M3) is the speed of the output shaft (41) when the mechanical transmission is in the third gear, n I is the rotation speed of the input shaft (11), and k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly (23).

7. The control method of the mechanical and electrical continuously variable composite transmission system according to claim 1, characterized in that: The method for calculating the rotation speed of the output shaft (41) of the EVT and mechanical compound transmission 1st gear (EVT-M1), the EVT and mechanical compound transmission 2nd gear (EVT-M2) and the EVT and mechanical compound transmission 3rd gear (EVT-M3) is as follows: EVT and mechanical compound transmission 1st gear (EVT-M1): Where n o (EVT-M1) is the speed of the output shaft (41) when the EVT and mechanical compound transmission are in the first gear, n I is the speed of the input shaft (11), i1 is the transmission ratio of the input gear pair (13), i2 is the transmission ratio of the output gear pair (45), i e is the transmission ratio of the electric transmission assembly (3), k1 is the characteristic parameter of the planetary gear of the front planetary gear assembly (22), k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly (23), and k3 is the characteristic parameter of the planetary gear of the output shaft assembly (4); EVT and mechanical compound transmission 2 gears (EVT-M2): Where n o (EVT-M2) is the speed of the output shaft (41) when the EVT and mechanical compound transmission are in the second gear, n I is the speed of the input shaft (11), i1 is the transmission ratio of the input gear pair (13), i2 is the transmission ratio of the output gear pair (45), i e is the transmission ratio of the electric transmission assembly (3), k3 is the characteristic parameter of the planetary gear of the output shaft assembly (4); EVT and mechanical compound transmission 3 gears (EVT-M3): Where n o (EVT-M3) is the output shaft (41) speed when the EVT and mechanical compound transmission are in the third gear, n I is the speed of the input shaft (11), i1 is the transmission ratio of the input gear pair (13), i2 is the transmission ratio of the output gear pair (45), i e is the transmission ratio of the electric transmission assembly (3), k2 is the characteristic parameter of the planetary gear of the rear planetary gear assembly (23), and k3 is the characteristic parameter of the planetary gear of the output shaft assembly (4).

Images