Hybrid power system and vehicle

Abstract

The invention relates to the technical field of new energy vehicles, in particular to a hybrid power system and a vehicle. The hybrid gearbox is of a longitudinal installation structure, and an output shaft of the hybrid gearbox faces the advancing direction of the vehicle; a mechanical front axle; the hybrid gearbox is connected with the mechanical front axle through the front transmission shaft; the electric drive rear axle is integrated with a rear drive motor, a rear axle speed reducer and a drive half shaft; the hybrid power system adopts a PS configuration; a power battery and a controller; by adopting the longitudinal design, the battery can be applied to hard non-bearing vehicle types such as pickup trucks and SUVs, the battery space utilization rate is higher, the battery arrangement space is larger, the battery arrangement is more convenient, the battery electric quantity is larger, and the pure power endurance is longer.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to a hybrid system and a vehicle. Background Art

[0002] With the rapid development of new energy technologies, new energy vehicles, especially hybrid vehicles, have gradually gained favor among consumers due to their advantages such as low cost, no range anxiety, and no charging anxiety. Compared with pure electric vehicles, hybrid vehicles do not need to frequently look for charging piles during long-distance driving, thus improving the user's driving experience.

[0003] At present, hybrid systems are mostly arranged in a transverse manner. There are very few longitudinal hybrid systems, and most of them are P2 parallel structures with a single motor and a multi-speed AT gearbox. Here is a brief explanation: the longitudinal P2 parallel structure places the electric motor between the internal combustion engine and the gearbox, combined with the flexible control of the clutch, to achieve efficient coordination between the internal combustion engine and the electric motor. The transverse structure is mostly used in load-bearing vehicles, and is not suitable for non-load-bearing vehicles such as hard-core SUVs and pickups. The P2 parallel structure retains the drive shaft that runs through the front and back, and the battery layout space is small and scattered. The battery layout is difficult and the power is small, and the pure electric range is short.

[0004] Therefore, how to overcome these limitations has become an urgent problem to be solved in the current development of hybrid electric vehicles. Summary of the invention

[0005] The purpose of the present invention is to provide a hybrid system that can adopt a longitudinal design and can be applied to hard-core non-load-bearing vehicles such as pickup trucks and SUVs, and has higher battery space utilization, larger battery layout space and more convenient layout, thereby increasing battery power and longer pure electric range.

[0006] Another object of the present invention is to provide a vehicle whose hybrid system can adopt a longitudinal design and can be applied to hard-core non-load-bearing vehicles such as pickup trucks and SUVs, and has higher battery space utilization, larger battery layout space and more convenient layout, thereby increasing battery power and longer pure electric range.

[0007] The technical solution of the present invention is achieved in this way:

[0008] A hybrid system, comprising:

[0009] An engine, wherein the output shaft of the engine is an engine power transmission shaft;

[0010] A hybrid gearbox, wherein the hybrid gearbox adopts a longitudinal installation structure, and the output shaft of the hybrid gearbox faces the forward direction of the vehicle;

[0011] Mechanical front axle;

[0012] a front transmission shaft, through which the hybrid transmission is connected to the mechanical front axle;

[0013] An electric drive rear axle, wherein the electric drive rear axle integrates a rear drive motor, a rear axle reducer and a drive half shaft;

[0014] The hybrid system adopts a PS configuration, wherein the hybrid gearbox includes a front-drive motor, a planetary gearbox and a three-speed transmission mechanism, the output shaft of the front-drive motor is the front-drive motor power transmission shaft, the input shaft and the output shaft of the three-speed transmission mechanism are the transmission mechanism input shaft and the transmission mechanism output shaft respectively, the planetary gearbox includes a sun gear, a planetary carrier and an outer gear ring, the sun gear is connected to the front-drive motor power transmission shaft, the planetary carrier is connected to the engine power transmission shaft, and the outer gear ring is connected to the transmission mechanism input shaft;

[0015] It also includes a power battery and a controller, wherein the power battery and the controller are arranged between the hybrid transmission and the electric drive rear axle, and the power battery is electrically connected to the front drive motor and the rear drive motor through the controller.

[0016] Furthermore, the hybrid transmission further comprises a torsional damper and a first clutch, wherein the torsional damper is arranged on the power transmission shaft of the engine and is located at the front end of the hybrid transmission to buffer the torque impact of the engine;

[0017] The first clutch is located behind the planetary gear, and the first clutch connects the power transmission shaft of the planetary carrier and the power transmission shaft of the outer gear ring.

[0018] Furthermore, the hybrid transmission also includes a first brake, which is arranged on the engine power transmission shaft and located before the first clutch to lock the engine power transmission shaft.

[0019] Furthermore, the hybrid transmission also includes a second brake, which is arranged on the front-drive motor power transmission shaft and is used to lock the front-drive motor power transmission shaft.

[0020] Furthermore, the hybrid transmission also includes a third brake, which is arranged on the input shaft of the transmission mechanism and located behind the planetary gearbox, and is used to lock the outer ring gear.

[0021] Furthermore, the three-speed transmission mechanism further includes a first-speed driving gear, a first-speed driven gear, a second-speed driving gear, a second-speed driven gear, a third-speed driving gear, and a third-speed driven gear;

[0022] The first gear driving gear and the second gear driving gear are respectively connected to the input shaft of the speed change mechanism through bearings, and the third gear driving gear is connected and fixed to the input shaft of the speed change mechanism;

[0023] The first gear driven gear, the second gear driven gear and the third gear driven gear are respectively connected and fixed to the output shaft of the speed change mechanism;

[0024] Furthermore, the three-speed transmission mechanism further includes a synchronizer, which is arranged on the input shaft of the transmission mechanism and located between the first-speed driving gear and the second-speed driving gear for switching gears.

[0025] Furthermore, the three-speed transmission mechanism also includes a second clutch, which is arranged on the output shaft of the transmission mechanism and located between the second-speed driven gear and the third-speed driven gear, and is used to cut off or transmit torque from the third-speed driving gear.

[0026] Furthermore, the electric drive rear axle is an integral rigid electric drive axle, and the electric drive rear axle adopts a coaxial electric drive axle.

[0027] A vehicle comprises the hybrid system, wherein the hybrid system has a pure electric mode, an engine mode, a series mode, a parallel mode, a power split mode and an energy feedback mode.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The hybrid system of the present application adopts a longitudinal design, that is, the hybrid gearbox adopts a longitudinal installation structure, and the output shaft of the hybrid gearbox faces the forward direction of the vehicle. Compared with the existing longitudinal P2 parallel structure, the longitudinal front output hybrid gearbox structure can be applied to hard-core non-load-bearing vehicles such as pickup trucks and SUVs, and has a wider range of applications; the hybrid gearbox is connected to the mechanical front axle through the front drive shaft. Compared with the P2 parallel structure, there is no drive shaft running through the front and back, and it can be applied to a variety of different models. The difference in layout position in the X direction (i.e., the lateral direction of the car or the width direction of the car) can be solved by adjusting the length of the front drive shaft. It is more versatile and can be applied to the layout positions of a variety of different models; and the hybrid system has no drive shaft running through the front and back, so the battery space utilization rate is higher, and the battery layout space is larger, which makes the battery layout more convenient, and thus the battery power can be larger and the pure electric endurance can be longer. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 is a schematic diagram of the overall structure of the hybrid system of the present invention;

[0032] Figure 2 It is a structural schematic diagram of the hybrid gearbox of the present invention;

[0033] Figure 3 A table showing various operating modes of the hybrid system of the present invention.

[0034] In the figure:

[0035] 1-Engine; 2-Hybrid gearbox; 3-Mechanical front axle; 4-Electric rear axle; 5-Controller; 6-Power battery; 7-Front drive shaft;

[0036] 20-torsion damper; 21-planetary gear; 22-three-speed transmission mechanism; 221-speed transmission mechanism input shaft; 222-speed transmission mechanism output shaft;

[0037] EM1-front drive motor; EM2-rear drive motor;

[0038] B1-first brake; B2-second brake; B3-third brake; C1-first clutch;

[0039] C2-second clutch; S1-synchronizer; G1-first gear driving gear; G1'-first gear driven gear; G2-second gear driving gear; G2'-second gear driven gear; G3-third gear driving gear; G3'-third gear driven gear. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0042] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0043] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0044] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0045] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0047] Example 1

[0048] Reference Figure 1-Figure 3 , a hybrid system, comprising:

[0049] Engine 1, the output shaft of engine 1 is the engine power transmission shaft;

[0050] The hybrid gearbox 2 adopts a longitudinal installation structure, and the output shaft of the hybrid gearbox 2 faces the forward direction of the vehicle;

[0051] Mechanical front axle 3;

[0052] A front transmission shaft 7, through which the hybrid transmission 2 is connected to the mechanical front axle 3;

[0053] The electric drive rear axle 4 integrates the rear drive motor EM2, the rear axle reducer and the drive half shaft;

[0054] The hybrid system adopts a PS configuration, wherein the hybrid transmission 2 includes a front-drive motor EM1, a planetary gearbox 21 and a three-speed transmission mechanism 22. The output shaft of the front-drive motor EM1 is the power transmission shaft of the front-drive motor EM1. The input shaft and the output shaft of the three-speed transmission mechanism 22 are the transmission mechanism input shaft 221 and the transmission mechanism output shaft 222, respectively. The planetary gearbox 21 includes a sun gear, a planetary carrier and an outer gear ring. The sun gear is connected to the power transmission shaft of the front-drive motor EM1, the planetary carrier is connected to the power transmission shaft of the engine, and the outer gear ring is connected to the transmission mechanism input shaft 221.

[0055] It also includes a power battery 6 and a controller 5 . The power battery 6 and the controller 5 are arranged between the hybrid transmission 2 and the electric drive rear axle 4 . The power battery 6 is electrically connected to the front drive motor EM1 and the rear drive motor EM2 through the controller 5 .

[0056] The hybrid transmission 2 further includes a torsional damper 20, a first clutch C1, a first brake B1, a second brake B2 and a third brake B3. The torsional damper 20 is disposed on the power transmission shaft of the engine 1 and is located at the front end of the hybrid transmission 2 to buffer the torque impact of the engine 1.

[0057] The first clutch C1 is located behind the planetary gear set 21 , and the first clutch C1 connects the power transmission shaft of the planetary carrier with the power transmission shaft of the outer ring gear.

[0058] The first brake B1 is arranged on the engine power transmission shaft and is located before the first clutch C1 to lock the engine power transmission shaft.

[0059] The second brake B2 is arranged on the power transmission shaft of the front drive motor EM1 and is used to lock the power transmission shaft of the front drive motor EM1.

[0060] The third brake B3 is arranged on the speed change mechanism input shaft 221 and is located behind the planetary gear 21 for locking the outer ring gear.

[0061] The PS configuration (Power Split) is a common architecture in hybrid systems. In a hybrid system, the PS configuration refers to a power split structure. The core of the PS configuration is that it uses a planetary gear set (i.e., a planetary gear set 21) to distribute the power generated by the engine 1 to drive the vehicle or charge the power battery 6.

[0062] In short, "the hybrid system adopts PS configuration" means that the system adopts a power split architecture, and realizes the power distribution and combination of engine 1 and power motor through the planetary gear set, thereby optimizing the vehicle's power performance and energy efficiency. The biggest advantage of the hybrid system adopting PS configuration is its smoothness and efficiency, which can flexibly adjust the power output according to the vehicle's driving conditions, improve fuel economy and reduce emissions.

[0063] The three-speed transmission mechanism 22 also includes a first-speed driving gear G1, a first-speed driven gear G1', a second-speed driving gear G2, a second-speed driven gear G2', a third-speed driving gear G3, and a third-speed driven gear G3';

[0064] The first gear driving gear G1 and the second gear driving gear G2 are connected to the transmission mechanism input shaft 221 through bearings, and the three can rotate independently of each other. The third gear driving gear G3 is connected and fixed to the transmission mechanism input shaft 221 by mechanical fixing, and the two can only rotate synchronously.

[0065] The first gear driven gear G1 ′, the second gear driven gear G2 ′ and the third gear driven gear G3 ′ are respectively connected and fixed to the speed change mechanism output shaft 222 by mechanical fixing means.

[0066] In this embodiment, the three-speed transmission mechanism 22 further includes a synchronizer S1 and a second clutch C2. The synchronizer S1 is arranged on the transmission mechanism input shaft 221 and is located between the first-speed driving gear G1 and the second-speed driving gear G2, and is used to switch gears. The second clutch C2 is arranged on the transmission mechanism output shaft 222 and is located between the second-speed driven gear G2' and the third-speed driven gear G3', and is used to cut off or transmit the torque from the third-speed driving gear G3.

[0067] The electric drive rear axle 4 integrates the rear drive motor EM2, the rear axle reducer and the drive half shaft. The electric drive rear axle 4 is an integral rigid electric drive axle, and the electric drive rear axle 4 adopts a coaxial electric drive axle.

[0068] In this embodiment, the front drive motor EM1 and the rear drive motor EM2 are EM motors, which refer to the electromechanical motor (EM motor for short). The function of the EM motor in the car is to convert electrical energy into mechanical energy through the principle of electromagnetic induction to drive various mechanical parts of the car to move.

[0069] In summary, the design of the hybrid system enables the engine 1 and the motors (front drive motor EM1 and rear drive motor EM2) to work independently or in coordination, thereby achieving multiple operating modes, as shown in the following table (also as shown in Figure 3 As shown), it should also be noted that EM1 refers to the front drive motor, EM2 refers to the rear drive motor, B1 refers to the first brake, B2 refers to the second brake, B3 refers to the third brake, C1 refers to the first clutch, C2 refers to the second clutch, G1 refers to the first gear driving gear, G2 refers to the second gear driving gear, G3 refers to the third gear driving gear, S1 refers to the synchronizer, and ICE refers to the internal combustion engine or engine 1.

[0070]

[0071]

[0072] In summary, the hybrid system has multiple working modes including pure electric mode, engine mode, series mode, parallel mode, power split mode and energy feedback mode, which can cover wider and more complex vehicle operating conditions and have lower material costs. The existing P2 parallel structure hybrid system has fewer working modes, limited improvement in vehicle economy and high cost of the hybrid system, and this hybrid system can solve this problem well.

[0073] The hybrid system of the present application adopts a longitudinal design, that is, the hybrid transmission 2 adopts a longitudinal installation structure, and the output shaft of the hybrid transmission 2 faces the forward direction of the vehicle. Compared with the existing longitudinal P2 parallel structure, the longitudinal front output hybrid transmission 2 structure can be applied to hard-core non-load-bearing vehicles such as pickup trucks and SUVs, and has a wider range of applications; the hybrid transmission 2 is connected to the mechanical front axle 3 through the front drive shaft 7. Compared with the P2 parallel structure, there is no drive shaft running through the front and back, and it can be applied to a variety of different models. The difference in layout position in the X direction (i.e., the lateral direction of the car or the width direction of the car) can be solved by adjusting the length of the front drive shaft 7. It is more versatile and can be applied to the layout positions of a variety of different models; and the hybrid system has no drive shaft running through the front and back, so the battery space utilization rate is higher, and the battery layout space is larger, which makes the battery layout more convenient, and thus the battery power can be larger and the pure electric endurance can be longer.

[0074] The electric drive rear axle 4 adopts a coaxial electric drive axle, which has better passability, compact structure, lower unsprung mass, better passability and smoothness compared with the offset electric drive axle.

[0075] The electric drive rear axle 4 is a vehicle-type rigid electric drive axle with stronger load-bearing capacity and better vehicle passability. It can be expanded to a pure electric platform (pure electric vehicle), has a higher degree of commonality and modularity, and at the same time has better vehicle passability.

[0076] The whole vehicle adopts the PS configuration of single-motor front-wheel drive and single-motor rear-wheel drive. The two motors can realize the functions of three motors in series-parallel configuration. The system cost is lower and the power splitting economy is better.

[0077] The hybrid transmission 2 is matched with a three-speed transmission mechanism 22, which has stronger power, and the operating conditions of the engine 1 and the front drive motor EM1 can fall more in the high-efficiency zone. The three-speed transmission mechanism 22 uses only one synchronizer S1, which has a more compact structure and lower material cost.

[0078] Hybrid Transmission 2 uses AMT transmission, which has higher transmission efficiency and lower material cost than AT transmission.

[0079] The front-drive motor EM1 can adjust the speed of the engine 1 in real time. In conditions of low battery, high load, and climbing, the front-drive motor EM1 can be used to adjust the engine 1 to run at a high speed. The series mode rear-wheel drive or power split mode four-wheel drive can be used to cope with such extreme conditions, thereby avoiding the problem that the engine 1 cannot intervene at high power in conditions of low battery, high load, and climbing.

[0080] The hybrid system is matched with a mechanical front axle (i.e., mechanical front axle 3), which can be used on the same platform as a fuel vehicle, making it more universal and modular.

[0081] Example 2

[0082] This embodiment provides a vehicle, including the hybrid system, and having all the advantages of the hybrid system.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hybrid system, characterized in that: include: An engine (1), wherein the output shaft of the engine (1) is an engine power transmission shaft; A hybrid gearbox (2), wherein the hybrid gearbox (2) adopts a longitudinal installation structure, and the output shaft of the hybrid gearbox (2) faces the forward direction of the vehicle; Mechanical front axle (3); A front transmission shaft (7), the hybrid transmission (2) is connected to the mechanical front axle (3) via the front transmission shaft (7); An electric drive rear axle (4), wherein the electric drive rear axle (4) is integrated with a rear drive motor (EM2), a rear axle reducer and a drive half shaft; The hybrid system adopts a PS configuration, wherein the hybrid transmission (2) comprises a front-drive motor (EM1), a planetary gearbox (21) and a three-speed transmission mechanism (22); the output shaft of the front-drive motor (EM1) is a power transmission shaft of the front-drive motor (EM1); the input shaft and the output shaft of the three-speed transmission mechanism (22) are respectively a transmission mechanism input shaft (221) and a transmission mechanism output shaft (222); the planetary gearbox (21) comprises a sun gear, a planetary carrier and an outer gear ring; the sun gear is connected to the power transmission shaft of the front-drive motor (EM1); the planetary carrier is connected to the power transmission shaft of the engine; and the outer gear ring is connected to the transmission mechanism input shaft (221); The invention also comprises a power battery (6) and a controller (5), wherein the power battery (6) and the controller (5) are arranged between the hybrid transmission (2) and the electric drive rear axle (4), and the power battery (6) is electrically connected to the front drive motor (EM1) and the rear drive motor (EM2) through the controller (5).

2. The hybrid system according to claim 1, characterized in that: The hybrid transmission (2) further comprises a torsional damper (20) and a first clutch (C1); the torsional damper (20) is arranged on the power transmission shaft of the engine (1) and is located at the front end of the hybrid transmission (2) for buffering the torque impact of the engine (1); The first clutch (C1) is located behind the planetary gear (21), and the first clutch (C1) connects the power transmission shaft of the planetary carrier and the power transmission shaft of the outer gear ring.

3. The hybrid system according to claim 2, characterized in that: The hybrid transmission (2) further comprises a first brake (B1), which is arranged on the engine power transmission shaft and located before the first clutch (C1) for locking the engine power transmission shaft.

4. The hybrid system according to claim 3, characterized in that: The hybrid transmission (2) further comprises a second brake (B2), which is arranged on the power transmission shaft of the front drive motor (EM1) and is used to lock the power transmission shaft of the front drive motor (EM1).

5. The hybrid system according to claim 4, characterized in that: The hybrid transmission (2) further comprises a third brake (B3), which is arranged on the transmission mechanism input shaft (221) and located behind the planetary gear (21) and is used to lock the outer gear ring.

6. The hybrid system according to claim 1, characterized in that: The three-speed transmission mechanism (22) further comprises a first-speed driving gear (G1), a first-speed driven gear (G1'), a second-speed driving gear (G2), a second-speed driven gear (G2'), a third-speed driving gear (G3), and a third-speed driven gear (G3'); The first gear driving gear (G1) and the second gear driving gear (G2) are respectively connected to the speed change mechanism input shaft (221) via bearings, and the third gear driving gear (G3) is connected and fixed to the speed change mechanism input shaft (221); The first gear driven gear (G1'), the second gear driven gear (G2') and the third gear driven gear (G3') are respectively connected and fixed to the speed change mechanism output shaft (222).

7. The hybrid system according to claim 6, characterized in that: The three-speed transmission mechanism (22) further comprises a synchronizer (S1), which is arranged on the transmission mechanism input shaft (221) and located between the first-speed driving gear (G1) and the second-speed driving gear (G2) for switching gears.

8. The hybrid system according to claim 7, characterized in that: The three-speed transmission mechanism (22) further comprises a second clutch (C2), which is arranged on the transmission mechanism output shaft (222) and located between the second-speed driven gear (G2') and the third-speed driven gear (G3') and is used to cut off or transmit torque from the third-speed driving gear (G3).

9. The hybrid system according to claim 1, characterized in that: The electric drive rear axle (4) is an integral rigid electric drive axle, and the electric drive rear axle (4) is a coaxial electric drive axle.

10. A vehicle, characterized in that: The hybrid system comprises the hybrid system as claimed in any one of claims 1 to 9, wherein the hybrid system has a pure electric mode, an engine mode, a series mode, a parallel mode, a power split mode and an energy feedback mode.

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