A control method for a range extender of a commercial vehicle and an energy supply system

Abstract

The present application discloses a control method and an energy supply system for a commercial vehicle range extender, relating to the technical field of range-extended electric vehicles. The method includes the following steps: The vehicle controller monitors the state of charge (SOC) of the power battery and the vehicle demand power in real time, and determines whether the SOC of the power battery is less than or equal to the lower SOC threshold. If not and the SOC of the power battery is less than or equal to the upper SOC threshold, proceed to the next step. If so, the vehicle controller controls the range extender to start. The vehicle controller determines whether the vehicle demand power is greater than or equal to the set power threshold. If so, the vehicle controller controls the range extender to start. If not, the range extender does not start. The range extender control method and the energy supply system of the present application add a control index for the vehicle demand power, and simultaneously control the range extender through two control indexes, namely the vehicle demand power and the SOC of the power battery, so as to maximize the efficiency of the range extender.

Description

Technical Field

[0001] This application relates to the technical field of range-extended electric vehicles, and particularly to a control method for a commercial vehicle range extender and an energy supply system. Background Art

[0002] Currently, in the field of commercial vehicles in our country, the vast majority use traditional engines as the vehicle power source. In recent years, with the popularization of new energy vehicle technologies worldwide, hybrid commercial vehicles with both power batteries and engines as the vehicle energy sources have developed well, and various hybrid forms have emerged in the market. Among them, range-extended electric vehicles are a good hybrid form and are increasingly widely used in the fields of commercial vehicles and passenger vehicles.

[0003] A range-extended electric vehicle is an electric vehicle that uses other energy sources (such as gasoline) to replenish electric energy when the power battery is insufficient. The main working characteristic of a range-extended electric vehicle is that it works in pure electric mode most of the time and in range-extended mode in a few cases, that is, the electric energy generated by the range extender system directly powers the motor and can also charge the power battery. Compared with traditional fuel vehicles, range-extended electric vehicles can effectively reduce energy consumption and emissions. Compared with pure electric vehicles, they can greatly overcome problems such as long charging time and short cruising range.

[0004] In related technologies, the traditional control method for range extenders is very simple, and only determines whether the range extender starts or not by judging the SOC of the vehicle power battery. When the SOC of the power battery is less than or equal to the critical threshold, the range extender starts to participate in work; when the SOC of the power battery is greater than the critical threshold, the range extender does not participate in work.

[0005] However, although the traditional range extender control method can supplement electric energy when the power battery is insufficient, the single control index (power battery SOC) makes the range extender in a standby state most of the time and does not maximize its own efficiency. Summary of the Invention

[0006] Aiming at the defects existing in the prior art, the purpose of this application is to provide a control method for a commercial vehicle range extender and an energy supply system, adding a control index of the vehicle's required power, and simultaneously controlling the range extender through two control indexes of the vehicle's required power and the power battery SOC to maximize the efficiency of the range extender.

[0007] To achieve the above object, the technical solution adopted is a control method for a commercial vehicle range extender. The commercial vehicle includes a vehicle controller, and the method includes the following steps:

[0008] The vehicle controller monitors the state of charge (SOC) of the power battery and the vehicle's required power in real time, and determines whether the SOC of the power battery is less than or equal to the lower SOC threshold; if not and the SOC of the power battery is less than or equal to the upper SOC threshold, proceed to the next step; if so, the vehicle controller controls the range extender to start.

[0009] The vehicle controller determines whether the vehicle's required power is greater than or equal to the set power threshold. If so, the vehicle controller controls the range extender to start; if not, the range extender does not start.

[0010] Based on the above technical solution, the range extender includes an engine controller, an engine, a generator controller, and a generator. Multiple power intervals are set in the vehicle controller. After the range extender starts, it includes:

[0011] The vehicle controller selects the power interval where it is located according to the magnitude of the vehicle's required power, and obtains the range extender power by looking up the vehicle required power - range extender power table.

[0012] The vehicle controller controls the engine through the engine controller and also controls the generator through the generator controller, and makes the output power of the generator equal to the range extender power.

[0013] Based on the above technical solution, the engine controller controls the engine power Pf, and the generator controller controls the energy conversion coefficient K of the engine to convert mechanical energy into electrical energy; the range extender power PZ = K × Pf.

[0014] Based on the above technical solution, the vehicle required power - range extender power table is obtained through prior calibration. The calibration method includes:

[0015] The vehicle controller equally-spaced selects n working points on the engine universal characteristic curve, and the engine powers corresponding to the n working points are P1, P2, P3…, Pn respectively; n is an integer and n ≥ 6.

[0016] According to multiple engine powers, the power intervals of the vehicle required power Preq are divided into KP1 ≤ Preq < KP2, KP2 ≤ Preq < KP3, KP3 ≤ Preq < KP4, …, KP(n - 2) ≤ Preq < KP(n - 1), Preq ≥ KPn.

[0017] For the case where the SOC of the power battery is less than or equal to the lower SOC threshold and the range extender starts, the range extender powers corresponding to each interval are calibrated in sequence as K(P1 + P2) / 2, K(P2 + P3) / 2, K(P3 + P4 ) / 2, …, K[P(n - 2) + P(n - 1)] / 2, KPn.

[0018] For the case where the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the range extender is started, the power threshold is set to KP(n - i), where i is an integer and greater than or equal to n / 2; the power of the range extender corresponding to the power interval with both boundaries less than KP(n - i) is 0, the power of the range extender corresponding to the power interval where Preq ≥ KPn is KPn; in the remaining power intervals, the power of the range extender is the average of the two boundaries of the power interval.

[0019] Based on the above technical solution, if the power of the range extender obtained by looking up the table is greater than the vehicle demand power, in addition to supplying energy to the motor, the excess power of the range extender can be used to charge the power battery.

[0020] Based on the above technical solution, after the range extender is started, when the SOC of the power battery is less than or equal to the lower SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the upper SOC threshold, and then the vehicle controller controls the range extender to turn off.

[0021] Based on the above technical solution, after the range extender is started, when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the full value, and then the vehicle controller controls the range extender to turn off.

[0022] This application also discloses an energy supply system, including a vehicle controller, a motor, a power battery, and a range extender using the above range extender control method;

[0023] The engine controller and the generator controller of the range extender are both connected to the vehicle controller through a low-voltage wire harness and a CAN wire;

[0024] An electrical signal interaction is carried out between the engine and the engine controller through a low-voltage wire harness;

[0025] The generator controller and the generator are connected by a low-voltage wire and a high-voltage wire, and at the same time, a low-voltage electrical signal interaction and a high-voltage current transmission are carried out;

[0026] The engine and the generator convert the mechanical energy of the engine into electrical energy through a mechanical connection method. The electrical energy directly supplies power to the motor and can also charge the power battery.

[0027] Based on the above technical solution, the range extender includes an engine controller, an engine, a generator controller, and a generator. Multiple power intervals are set in the vehicle controller. After the range extender is started, it includes:

[0028] The vehicle controller selects its power range according to the magnitude of the vehicle's required power, and obtains the range extender power by looking up the vehicle required power - range extender power table;

[0029] The vehicle controller controls the engine through the engine controller, and also controls the generator through the generator controller, and makes the output power of the generator equal to the range extender power.

[0030] On the basis of the above technical solution, the engine controller controls the engine power Pf, and the generator controller controls the energy conversion coefficient K from the mechanical energy of the engine to the electrical energy of the generator; the range extender power PZ = K × Pf.

[0031] The beneficial effects brought by the technical solution provided in this application include:

[0032] 1. For the range extender control method of this application, a new control index for the range extender, namely the vehicle required power, is added. When the power battery SOC is less than or equal to the set lower SOC threshold, or when the power battery SOC is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the vehicle required power is greater than or equal to the set power threshold of the range extender, the range extender starts; when the power battery SOC is greater than the upper SOC threshold, or when the power battery SOC is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the vehicle required power is less than the set power threshold, the range extender does not start, and the power battery SOC normally supplies energy to the motor.

[0033] Compared with the traditional range extender control method that only controls the opening and closing of the range extender by comparing the power battery SOC with the lower SOC threshold, adding a new control index of vehicle required power and also adding a set upper SOC threshold, the two control indexes of this application interact to control the range extender, enabling the range extender to be used under more working conditions, maximizing the efficiency of the range extender, and protecting the battery to the greatest extent and prolonging the battery life.

[0034] 2. For the range extender control method of this application, when the power battery SOC is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the vehicle required power is greater than or equal to the set power threshold of the range extender, the range extender starts, maximizing the utilization of the range extender efficiency, while reducing the situation of insufficient power in the power battery SOC, indirectly protecting the power battery and increasing the life of the power battery.

[0035] 3. The range extender control method of the present application is as follows: after the range extender is started, when the state of charge (SOC) of the power battery is less than or equal to the lower SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery increases until the SOC of the power battery reaches the upper SOC threshold, at which time the vehicle controller controls the range extender to turn off. When the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery increases until the SOC of the power battery reaches the full value, at which time the vehicle controller controls the range extender to turn off. The range extender control method of the present application forms a closed-loop control of the range extender, which can effectively protect the power battery, automatically switch the on / off state of the range extender, and has a clever control. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 It is a schematic diagram of the power supply system provided by the embodiment of the present application;

[0038] Figure 2 It is a flowchart of the range extender control method provided by the embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] In order to make the purpose, technical solutions and advantages of the present application clearer, the following will further describe the present invention in detail with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] As Figure 1 and Figure 2 shown, the present application discloses a control method for a commercial vehicle range extender, which adds a control index of vehicle demand power and controls the range extender through two control indexes of vehicle demand power and the state of charge (SOC) of the power battery, so that the range extender can be used under more working conditions and the efficiency of the range extender can be maximized.

[0041] Specifically, the commercial vehicle includes a vehicle controller, and the range extender control method includes the following steps:

[0042] The vehicle controller monitors the state of charge (SOC) of the power battery and the vehicle's required power in real time. First, the vehicle controller determines whether the current SOC of the power battery is less than or equal to the lower SOC threshold. If not and the SOC of the power battery is less than or equal to the upper SOC threshold, it means the power battery has sufficient power and the next step is carried out. If so, that is, the SOC of the power battery is less than or equal to the lower SOC threshold, it means the power battery has insufficient power, and the vehicle controller controls the range extender to start.

[0043] The vehicle controller monitors the vehicle's required power in real time. Specifically, the vehicle's required power is related to the accelerator of the electric vehicle. The vehicle controller determines in real time whether the vehicle's required power is greater than or equal to the set power threshold. If so, that is, the vehicle's required power is greater than or equal to the set power threshold, it means the energy consumption is fast, and the vehicle controller controls the range extender to start. If not, that is, the vehicle's required power is less than the set power threshold, it means the energy consumption is not fast, and the SOC of the power battery normally supplies power to the motor.

[0044] For the range extender control method of this application, a new control index for the range extender, namely the vehicle's required power, is added. When the SOC of the power battery is less than or equal to the set lower SOC threshold, or when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the vehicle's required power is greater than or equal to the set power threshold of the range extender, the range extender starts. When the SOC of the power battery is greater than the upper SOC threshold, or when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the vehicle's required power is less than the set power threshold, the range extender does not start, and the SOC of the power battery normally supplies power to the motor.

[0045] In one implementation, the upper SOC threshold is set to 80% and the lower SOC threshold is set to 20%.

[0046] When the SOC of the power battery is greater than 80%, it means the power is very sufficient. At this time, even regardless of the relationship between the vehicle's required power and the set power threshold, the range extender does not start.

[0047] When the SOC of the power battery is greater than 20% and less than or equal to 80% and the vehicle's required power is less than the set power threshold, the range extender does not start, indicating that the power is sufficient and the energy consumption is slow, so the range extender does not start.

[0048] When the SOC of the power battery is less than or equal to 20%, it means the power is very insufficient. At this time, even regardless of the relationship between the vehicle's required power and the set power threshold, the range extender starts.

[0049] Or when the SOC of the power battery is greater than 20% and less than or equal to 80% and the vehicle's required power is greater than or equal to the set power threshold of the range extender, it means the power is sufficient and the energy consumption is fast, and the range extender starts.

[0050] Compared with the traditional range extender control method that only controls the opening and closing of the range extender by comparing the state of charge (SOC) of the power battery with the lower SOC threshold, the two control indicators of this application control the range extender simultaneously, enabling the range extender to be used under more working conditions, maximizing the efficiency of the range extender, protecting the battery to the greatest extent, and prolonging the battery life.

[0051] In one embodiment, the range extender includes an engine controller, an engine, a generator controller, and a generator. Multiple power ranges are set in the vehicle controller. After the range extender is started, it includes:

[0052] The vehicle controller selects the power range where it is located according to the magnitude of the vehicle's required power, and obtains the range extender power by looking up the vehicle required power - range extender power table.

[0053] The vehicle controller controls the engine through the engine controller and also controls the generator through the generator controller, and makes the output power of the generator equal to the range extender power.

[0054] Specifically, the vehicle required power - range extender power table is obtained through prior calibration, and this vehicle required power - range extender power table can meet the energy supply in the case where the SOC of the power battery is less than or equal to the lower SOC threshold and the range extender is started, and can also reasonably share the energy supply in the case where the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the range extender is started.

[0055] The range extender control method of this application can start the range extender when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the vehicle's required power is greater than or equal to the set power threshold of the range extender, maximizing the utilization of the range extender's efficiency, while reducing the situation of insufficient power in the SOC of the power battery, indirectly protecting the power battery, and increasing the life of the power battery.

[0056] In one embodiment, the engine controller controls the engine power Pf, and the generator controller controls the energy conversion coefficient K of converting mechanical energy of the engine into electrical energy; the range extender power PZ = K × Pf, where K is less than 1, and the engine controller and the generator controller cooperate to make the output power of the motor reach the power desired by the range extender. In this application, K is a fixed constant.

[0057] In one embodiment, the vehicle required power - range extender power table is obtained through prior calibration, and the calibration method includes:

[0058] The vehicle controller equally-spacedly selects n working points on the optimal fuel consumption curve in the engine universal characteristic curve, and the engine powers Pf corresponding to the n working points are P1, P2, P3, …, Pn respectively; n is an integer and greater than or equal to 6. P1, P2, P3, …, Pn can cover the range of vehicle demand power from low demand to high demand.

[0059] According to the multiple engine powers, the power intervals of the vehicle demand power Preq are respectively KP1 ≤ Preq < KP2, KP2 ≤ Preq < KP3, KP3 ≤ Preq < KP4, …, KP(n - 2) ≤ Preq < KP(n - 1), Preq ≥ KPn;

[0060] In the case where the power battery SOC is less than or equal to the lower SOC threshold and the range extender starts, the range extender powers corresponding to each interval are calibrated as K(P1 + P2) / 2, K(P2 + P3) / 2, K(P3 + P4) / 2, …, K[P(n - 2) + P(n - 1)] / 2, KPn in sequence;

[0061] In the case where the power battery SOC is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the range extender starts, the power threshold is set as P(n - i), where i is an integer and greater than or equal to n / 2; the range extender powers corresponding to the power intervals with both boundaries less than KP(n - i) are all 0, and the range extender power corresponding to the power interval Preq ≥ KPn is KPn; in the remaining power intervals, the range extender power is the average value of the two boundaries of the power interval.

[0062] Wherein, K is equal to the electric energy output by the generator divided by the mechanical energy output by the engine.

[0063] In a certain instance, the vehicle controller equally-spacedly selects 6 working points on the optimal fuel consumption curve in the engine universal characteristic curve, that is, n = 6, and the engine powers corresponding to the 6 working points are P1, P2, P3, P4, P5 and P6; i = 2, and the power threshold is set as KP4.

[0064] The vehicle demand power - range extender power table is shown in Table 1

[0065] Table 1

[0066]

[0067] P1, P2, P3, P4, P5 and P6 can cover the range of vehicle demand power from low demand to high demand, and record the corresponding torque and speed points.

[0068] According to the second row and the fourth row of the vehicle demand power - range extender power table, it can be known that:

[0069] When the state of charge (SOC) of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the vehicle's required power Preq is less than the set power threshold KP4, it indicates that the battery has sufficient power and slow energy consumption, so the range extender does not start. At this time, the vehicle's required power is fully provided by the power battery.

[0070] When the state of charge (SOC) of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the vehicle's required power is greater than or equal to the set power threshold KP4, it indicates that the battery has sufficient power but fast energy consumption. Select the power interval where it is located according to the vehicle's required power Preq. If the vehicle's required power is less than P4, the range extender does not start. If the vehicle's required power is in the range of KP4 ≤ Preq < KP5, the range extender starts at this time, and the power of the range extender is K(P4 + P5) / 2. When the vehicle's required power is in the range of KP5 ≤ Preq < KP6, the range extender starts at this time, and the power of the range extender is K(P5 + P6) / 2. When the vehicle's required power is Preq ≥ KP6, the range extender starts at this time, and the power of the range extender is KP6.

[0071] According to the second and third rows of the vehicle required power - range extender power table, it can be known that:

[0072] When the state of charge (SOC) of the power battery is less than or equal to the lower SOC threshold, regardless of the external vehicle required power, the range extender is turned on at this time.

[0073] The power of the range extender is selected as:

[0074] When the vehicle's required power is KP1 ≤ Preq < KP2, the power of the range extender is K(P1 + P2) / 2 at this time; when the vehicle's required power is KP2 ≤ Preq < KP3, the power of the range extender is K(P2 + P3) / 2 at this time; when the vehicle's required power is KP3 ≤ Preq < KP4, the power of the range extender is K(P3 + P4) / 2 at this time; when the vehicle's required power is KP4 ≤ Preq < KP5, the power of the range extender is K(P4 + P5) / 2 at this time; when the vehicle's required power is KP5 ≤ Preq < KP6, the power of the range extender is K(P5 + P6) / 2 at this time; when the vehicle's required power is Preq ≥ KP6, the power of the range extender is KP6.

[0075] In one embodiment, if the power of the range extender obtained by looking up the table is greater than the vehicle's required power, in addition to supplying power to the motor, the excess power of the range extender can be used to charge the power battery, making it less likely for the power battery's power to reach the insufficient power situation, effectively protecting the power battery and extending its service life.

[0076] Furthermore, after the range extender is started, when the state of charge (SOC) of the power battery is less than or equal to the lower SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the upper SOC threshold, at which point the vehicle control unit controls the range extender to shut down.

[0077] At this time, the vehicle starts with insufficient power. As the range extender runs slowly, the power becomes more and more, and after the power is sufficient, it resumes power supply from the power battery.

[0078] Even further, after the range extender is started, when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the full value, at which point the vehicle control unit controls the range extender to shut down.

[0079] At this time, the vehicle starts with sufficient power. As the range extender runs slowly, the power becomes more and more until it is full; at this time, even if it is still in a state of fast energy consumption, the range extender still needs to be shut down and resume power supply from the power battery.

[0080] For the range extender control method of the present application, after the range extender is started, when the SOC of the power battery is less than or equal to the lower SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the upper SOC threshold, at which point the vehicle control unit controls the range extender to shut down.

[0081] When the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery becomes larger and larger until the SOC of the power battery reaches the full value, at which point the vehicle control unit controls the range extender to shut down.

[0082] The range extender control method of the present application forms a closed-loop control of the range extender, which can effectively protect the power battery, automatically switch the opening and closing state of the range extender, and has a clever control.

[0083] The present application also discloses an energy supply system, which includes a vehicle control unit, an electric motor, a power battery, and a range extender that adopts the above range extender control method.

[0084] The engine controller and the generator controller of the range extender are both connected to the vehicle controller through low-voltage harnesses, and the engine controller and the generator controller are also connected to the vehicle controller through CAN lines. Electrical signal interaction is carried out between the engine and the engine controller through a low-voltage harness. The generator controller and the generator are connected by a low-voltage line and a high-voltage line, and at the same time, low-voltage electrical signal interaction and high-voltage current transmission are carried out. The mechanical energy of the engine is converted into electrical energy of the generator through a mechanical connection between the engine and the generator, and the electrical energy directly powers the motor and can also charge the power battery.

[0085] Regarding the energy supply system, in one embodiment, the range extender includes an engine controller, an engine, a generator controller, and a generator. Multiple power ranges are set in the vehicle controller. After the range extender is started, it includes:

[0086] The vehicle controller selects the power range it is in according to the magnitude of the vehicle's required power and obtains the range extender power by looking up the vehicle required power - range extender power table;

[0087] The vehicle controller controls the engine through the engine controller and also controls the generator through the generator controller, and makes the output power of the generator equal to the range extender power.

[0088] Specifically, the vehicle required power - range extender power table is obtained through prior calibration, and this vehicle required power - range extender power table can meet the energy supply in the case where the state of charge (SOC) of the power battery is less than or equal to the lower SOC threshold and the range extender is started, and can also reasonably share the energy supply in the case where the SOC of the power battery is greater than the lower SOC threshold and the range extender is started.

[0089] The energy supply system of the present application can start the range extender when the SOC of the power battery is greater than the lower SOC threshold and the vehicle's required power is greater than or equal to the set power threshold of the range extender, maximize the utilization efficiency of the range extender, and at the same time reduce the situation of insufficient power in the SOC of the power battery, indirectly protecting the power battery and increasing the service life of the power battery.

[0090] Regarding the energy supply system, in one embodiment, the engine controller controls the engine power Pf, and the generator controller controls the energy conversion coefficient K from the mechanical energy of the engine to the electrical energy of the generator; the range extender power PZ = K × Pf, where K is less than 1, and the engine controller and the generator controller cooperate to make the output power of the motor reach the power desired by the range extender.

[0091] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present application 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. Therefore, it should not be construed as a limitation to the present application. Unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0092] It should be noted that in the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising one..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the said element.

[0093] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A control method for a range extender of a commercial vehicle, the commercial vehicle including a vehicle controller, characterized in that, It includes the steps: The vehicle controller monitors the SOC of the power battery and the vehicle demand power in real time, and determines whether the SOC of the power battery is less than or equal to the lower SOC threshold; if not and the SOC of the power battery is less than or equal to the upper SOC threshold, proceed to the next step; if not and the SOC of the power battery is greater than the upper SOC threshold, the range extender does not start; if so, the vehicle controller controls the range extender to start; The vehicle controller determines whether the vehicle demand power is greater than or equal to the set power threshold; if so, the vehicle controller controls the range extender to start; if not, the range extender does not start; The range extender includes an engine controller, an engine, a generator controller and a generator. Multiple power intervals are set in the vehicle controller. After the range extender starts, it includes: The vehicle controller selects the power interval where it is located according to the magnitude of the vehicle demand power, and obtains the range extender power by looking up the vehicle demand power - range extender power table; The vehicle controller controls the engine through the engine controller, and also controls the generator through the generator controller, and makes the output power of the generator equal to the range extender power; If the range extender power obtained by looking up the table is greater than the vehicle demand power, in addition to supplying energy to the motor, the excess power of the range extender can be used to charge the power battery; The engine controller controls the engine power Pf, and the generator controller controls the energy conversion coefficient K of the engine to convert mechanical energy into electrical energy; K is a customized constant less than 1; The range extender power PZ = K × Pf; The vehicle demand power - range extender power table is obtained through prior calibration. The calibration method includes: The vehicle controller evenly selects n working points on the engine universal characteristic curve, and the engine powers corresponding to the n working points are P1, P2, P3…, Pn respectively; n is an integer and greater than or equal to 6; The power intervals of the vehicle demand power Preq are divided according to multiple engine powers as KP1 ≤ Preq < KP2, KP2 ≤ Preq < KP3, KP3 ≤ Preq < KP4, …, KP(n - 2) ≤ Preq < KP(n - 1), Preq ≥ KPn; For the case where the SOC of the power battery is less than or equal to the lower SOC threshold and the range extender starts, the range extender powers corresponding to each interval are sequentially K(P1 + P2) / 2, K(P2 + P3) / 2, K(P3 + P4 ) / 2, …, K[P(n - 2) + P(n - 1)] / 2, KPn; For the case where the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold and the range extender starts, the set power threshold is KP(n - i), where i is an integer and greater than or equal to n / 2; the range extender powers corresponding to the power intervals with both boundaries less than KP(n - i) are all 0, and the range extender power corresponding to the power interval Preq ≥ KPn is KPn; in the remaining power intervals, the range extender power is the average value of the two boundaries of the power interval.

2. The control method of a range extender for a commercial vehicle according to claim 1, characterized in that: After the range extender is started, when the SOC of the power battery is less than or equal to the lower SOC threshold and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery increases until the SOC of the power battery reaches the upper SOC threshold, and then the vehicle controller controls the range extender to shut down.

3. The control method of a range extender for a commercial vehicle according to claim 1, characterized in that: After the range extender is started, when the SOC of the power battery is greater than the lower SOC threshold and less than or equal to the upper SOC threshold, and the power of the range extender is greater than the vehicle demand power, the excess power of the range extender charges the power battery, and the SOC of the power battery increases until the SOC of the power battery reaches the full value, and then the vehicle controller controls the range extender to shut down.

4. A power supply system, characterized in that, Comprising a vehicle controller, an electric motor, a power battery, and a range extender adopting the range extender control method as claimed in claim 1; The engine controller and the generator controller of the range extender are both connected to the vehicle controller through a low-voltage harness and a CAN line; An electrical signal interaction is carried out between the engine and the engine controller through a low-voltage harness; The generator controller and the generator are connected by a low-voltage wire and a high-voltage wire, and at the same time, a low-voltage electrical signal interaction and a high-voltage current transmission are carried out; Between the engine and the generator, the mechanical energy of the engine is converted into electrical energy through a mechanical connection method, and the electrical energy directly powers the electric motor and can also charge the power battery.

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