A control method for parking power generation of a range extended electric vehicle

Abstract

The application discloses a kind of range-extended electric vehicle parking power generation control methods, comprising the following steps: step S10, parking power generation function is opened;Step S20, whether MP5 end selects efficient mode, if yes, then step S21 is carried out, if not, then step S22 is carried out;Step S21, VCU is based on battery charging power limit, from range extender efficiency Map, select optimal oil-electric conversion efficiency power point, request range extender power generation, then step S30 is carried out;Step S22, whether MP5 end selects "speed" charging mode, if not, then step S23 is carried out, if yes, then step S24 is carried out.The application solves the problem that existing battery will appear battery overcharge in the process of parking charging, seriously damage the health and life of battery, and synchronously solves the problem that battery cell temperature will be reduced in winter environment temperature is lower, battery cannot reach full power charging state, reduces battery charging efficiency.

Description

A method for controlling the parking power generation of a range-extended electric vehicle Technical Field

[0001] This invention belongs to the field of plug-in hybrid electric vehicle technology. Specifically, this invention relates to a parking power generation control method for range-extended electric vehicles. Background Technology

[0002] Electric vehicles (BEVs) are vehicles that use onboard power sources to drive the wheels with electric motors and meet all road traffic and safety regulations. Because they have a relatively smaller environmental impact than traditional cars, their prospects are widely regarded as promising. Range-extended electric vehicles, compared to pure electric vehicles, add a range extender module.

[0003] The range extender module consists of an engine, a generator, an engine controller, and a generator controller (hereinafter referred to as "GCU"). The vehicle controller (hereinafter referred to as "VCU") will decide whether to start the range extender and the power output of the range extender after starting based on the battery SOC and the driver's intention. It can not only supply power to the vehicle's own drive system, battery, and high-voltage auxiliary components, but also supply power to external sources if a bidirectional OBC is configured.

[0004] However, existing batteries may overcharge during parking and charging, which can seriously damage the battery's health and lifespan. In addition, in winter, when the ambient temperature is low, the battery cell temperature will drop, preventing the battery from reaching full power charging and reducing charging efficiency. Summary of the Invention

[0005] This invention provides a parking power generation control method for range-extended electric vehicles, which solves the problems mentioned in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for controlling the power generation while parking in a range-extended electric vehicle, comprising the following steps:

[0007] Step S10: Turn on the parking generator function;

[0008] Step S20: Determine whether the MP5 terminal selects the high-efficiency mode. If yes, proceed to step S21; otherwise, proceed to step S22.

[0009] Step S21: Based on the battery charging power limit, the VCU selects the optimal oil-electric conversion efficiency power point from the range extender efficiency Map, requests the range extender to generate electricity, and then proceeds to step S30.

[0010] Step S22: Determine whether the MP5 terminal selects the "speed" charging mode. If not, proceed to step S23; otherwise, proceed to step S24.

[0011] In step S23, the VCU executes the default charging mode, taking into account power generation efficiency, power generation rate and vehicle NVH performance to determine the power generation capacity, and then proceeds to step S30.

[0012] Step S24: Further select different power generation speeds at the MP5 end;

[0013] Step S25: The VCU is converted into the corresponding power value under the maximum requestable power generation capacity;

[0014] Step S30: The VCU calculates the range extender's power generation request P based on the current parking power generation mode. base .

[0015] Preferably, after step S30, the following steps are also included:

[0016] Step S40: Determine whether the battery self-heating contactor is in the closed state; otherwise, execute P1=P base If so, then execute P1 = P base +2.7kW, and then proceed to step S50;

[0017] Step S50: Determine whether the air conditioner or heater is in operation. If not, execute P1 = P2; if so, execute P2 = P1 + P PAC / PTC Then proceed to step S60;

[0018] In step S60, the VCU sends P to the GCU, where P ≤ Min (maximum power limit for continuous battery charging and maximum power limit for continuous range extender generation).

[0019] Preferably, after step S60, the following steps are also included:

[0020] Step S70: The VCU calculates the time required to fully charge the battery based on the actual power output of the range extender and the remaining battery charge.

[0021] Step S80: The MP5 terminal displays the time required to fully charge the remaining battery in real time;

[0022] Step S90: Determine whether the vehicle meets any of the following parking charging conditions:

[0023] 1. Battery SOC > 90%;

[0024] 2. Vehicle speed: 1 km / h;

[0025] 3. The gear is not neutral (N).

[0026] 4. Release the parking brake;

[0027] 5. Engine stops abnormally;

[0028] If yes, then stop the parking power generation; otherwise, return to step S90 to continue judging the vehicle.

[0029] Preferably, the following steps are provided before step S10:

[0030] Step S01: High voltage is ready for the entire vehicle;

[0031] Step S02: Determine whether the MP5 terminal requests parking power generation. If yes, proceed to step S03; otherwise, return to step S02 and repeat the determination.

[0032] Step S03: Determine whether the battery SOC is less than 90%, the vehicle speed is less than 1 km / h, the gear is in N gear, and the parking brake is engaged. If so, proceed to step S10; otherwise, return to step S03 and repeat the determination.

[0033] Step S04 runs synchronously with step S02. The BMS determines whether the cell temperature is lower than the self-heating threshold. If so, proceed to step S05; otherwise, return to step S04 and repeat the determination.

[0034] Step S05: After a 10-second delay, the BMS activates self-heating.

[0035] Preferably, after step S10, the following steps are also included:

[0036] Step S11, which runs synchronously with step S20, involves the VCU sending the actual status of the parking power generation to the BMS.

[0037] Step S12: The BMS determines whether to enable self-heating temperature switching based on the cell temperature.

[0038] Step S13: Determine whether the battery has switched the battery self-heating cutoff temperature. If yes, proceed to step S14; otherwise, return to step S12 and repeat the determination.

[0039] Step S14: The BMS controls the heating film to heat up to the cutoff temperature and then stops.

[0040] Preferably, after step S10, the following steps are also included:

[0041] Step S15, which runs synchronously with step S11, involves the VCU issuing a start command for the range extender to the GCU.

[0042] Step S16: The GCU controls the range extender to start.

[0043] The beneficial effects of adopting the above technical solutions are:

[0044] 1. To prevent battery overcharging, which could severely damage battery health and lifespan, the battery's State of Charge (SOC) is considered simultaneously. If the battery's SOC exceeds the upper limit for power generation (e.g., 90%), parking power generation will not be enabled to protect the battery. Since the purpose of parking power generation is clearly defined—to fully charge the battery to meet subsequent power demands—the upper limit of the battery SOC for parking power generation is set at a fixed value of 90% (considering battery cycle life). If the user wants to terminate parking power generation early, they can directly turn it off at the MP5 terminal or apply high voltage to the entire vehicle. If the parking power generation function is enabled and activated, and the VCU receives a signal to turn off parking power generation at the MP5 terminal, or if high voltage is applied to the entire vehicle, the VCU will control the engine to shut down.

[0045] Second, in winter, the ambient temperature is low, and the battery cell temperature will decrease. For batteries equipped with self-heating functions, after the vehicle is connected to high voltage, the Battery Management System (BMS) will decide to first self-heat the battery based on the cell temperature to quickly reach a state with strong discharge capacity. The self-heating cutoff temperature of a conventional battery is not too high (e.g., 10°C) to minimize the power consumption of battery self-heating. For parking and power generation scenarios in cold winter conditions, the battery needs to quickly reach a state where it can be charged at full power to meet the demand for rapid charging of the battery during parking and power generation. Therefore, the Vehicle Control Unit (VCU) will send a message to the BMS indicating whether the parking and power generation is on. After receiving this signal, the BMS will switch the battery self-heating cutoff temperature to a higher temperature point that can achieve full power generation performance (e.g., 20°C) to allow the range extender to generate power quickly. At the same time, the VCU will compensate for the power consumption of battery self-heating based on the status of the battery self-heating contactor to ensure the battery charging speed. Attached Figure Description

[0046] Figure 1 is an overall flowchart provided by the present invention;

[0047] Figure 2 is a flowchart of the first part of the present invention;

[0048] Figure 3 is a flowchart of the second part of the present invention;

[0049] Figure 4 is a flowchart of the third part of the present invention;

[0050] Figure 5 is a flowchart of the fourth part of the present invention;

[0051] Figure 6 is a flowchart of the fifth part of this invention; Detailed Implementation

[0052] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solutions of the present invention, and to facilitate its implementation.

[0053] Specifically, as shown in Figures 1 to 6, a method for controlling the parking-based power generation of a range-extended electric vehicle includes the following steps:

[0054] Step S10: Turn on the parking generator function;

[0055] Step S20: Determine whether the MP5 terminal selects the high-efficiency mode. If yes, proceed to step S21; otherwise, proceed to step S22.

[0056] Step S21: Based on the battery charging power limit, the VCU selects the optimal oil-electric conversion efficiency power point from the range extender efficiency Map, requests the range extender to generate electricity, and then proceeds to step S30.

[0057] Step S22: Determine whether the MP5 terminal selects the "speed" charging mode. If not, proceed to step S23; otherwise, proceed to step S24.

[0058] In step S23, the VCU executes the default charging mode, taking into account power generation efficiency, power generation rate and vehicle NVH performance to determine the power generation capacity, and then proceeds to step S30.

[0059] Step S24: Further select different power generation speeds at the MP5 end;

[0060] Step S25: The VCU is converted into the corresponding power value under the maximum requestable power generation capacity;

[0061] Step S30: The VCU calculates the range extender's power generation request P based on the current parking power generation mode. base .

[0062] Preferably, after step S30, the following steps are also included:

[0063] Step S40: Determine whether the battery self-heating contactor is in the closed state; otherwise, execute P1=P base If so, then execute P1 = P base +2.7kW, and then proceed to step S50;

[0064] Step S50: Determine whether the air conditioner or heater is in operation. If not, execute P1 = P2; if so, execute P2 = P1 + P PAC / PTC Then proceed to step S60;

[0065] In step S60, the VCU sends P to the GCU, where P ≤ Min (maximum power limit for continuous battery charging and maximum power limit for continuous range extender generation).

[0066] Following step S60, the following steps are also set:

[0067] Step S70: The VCU calculates the time required to fully charge the battery based on the actual power output of the range extender and the remaining battery charge.

[0068] Step S80: The MP5 terminal displays the time required to fully charge the remaining battery in real time;

[0069] Step S90: Determine whether the vehicle meets any of the following parking charging conditions:

[0070] 1. Battery SOC > 90%;

[0071] 2. Vehicle speed: 1 km / h;

[0072] 3. The gear is not neutral (N).

[0073] 4. Release the parking brake;

[0074] 5. Engine stops abnormally;

[0075] If yes, then stop the parking power generation; otherwise, return to step S90 to continue judging the vehicle.

[0076] The following steps are set before step S10:

[0077] Step S01: High voltage is ready for the entire vehicle;

[0078] Step S02: Determine whether the MP5 terminal requests parking power generation. If yes, proceed to step S03; otherwise, return to step S02 and repeat the determination.

[0079] Step S03: Determine whether the battery SOC is less than 90%, the vehicle speed is less than 1 km / h, the gear is in N gear, and the parking brake is engaged. If so, proceed to step S10; otherwise, return to step S03 and repeat the determination.

[0080] It should be noted that the VCU will first determine whether the vehicle has come to a complete stop. This function can only be enabled under the premise of ensuring safety, namely, the vehicle speed is less than 1 km / h, the parking brake is engaged, and the vehicle is currently in neutral (N) gear, to ensure that the vehicle has come to a reliable stop.

[0081] Step S04 runs synchronously with step S02. The BMS determines whether the cell temperature is lower than the self-heating threshold. If so, proceed to step S05; otherwise, return to step S04 and repeat the determination.

[0082] Step S05: After a 10-second delay, the BMS activates self-heating.

[0083] It should be noted that to prevent battery overcharging, which could severely damage the battery's health and lifespan, the battery's State of Charge (SOC) is also considered. If the battery's SOC exceeds the upper limit for power generation (e.g., 90%), parking power generation will not be enabled to protect the battery. Since the purpose of parking power generation is clearly defined—to fully charge the battery as much as possible to meet subsequent power demands—the upper limit of the battery SOC for parking power generation is set at a fixed value of 90% (considering battery cycle life). If the user wants to terminate parking power generation early, they can directly turn it off at the MP5 terminal or apply high voltage to the entire vehicle. If the parking power generation function is enabled and activated, and the VCU receives a signal to turn off parking power generation at the MP5 terminal, or if high voltage is applied to the entire vehicle, the VCU will control the engine to shut down.

[0084] Step S10 is followed by the following steps:

[0085] Step S11, which runs synchronously with step S20, involves the VCU sending the actual status of the parking power generation to the BMS.

[0086] Step S12: The BMS determines whether the self-heating temperature can be switched based on the cell temperature.

[0087] Step S13: Determine whether to switch the battery self-heating cutoff temperature. If yes, proceed to step S14; otherwise, return to step S12 and repeat the determination.

[0088] Step S14: The BMS controls the heating film to heat up to the cutoff temperature and then stops.

[0089] It should be noted that in winter, the ambient temperature is low, and the battery cell temperature will decrease. For batteries equipped with self-heating function, after the vehicle is connected to high voltage, the battery management system (hereinafter referred to as "BMS") will decide to first self-heat the battery based on the cell temperature to quickly reach a state with strong discharge capacity. The self-heating cutoff temperature of conventional batteries is not too high (e.g., 10℃) to minimize the power consumption of battery self-heating. For the parking power generation scenario in the cold winter state, it is necessary to quickly bring the battery to a state that can be charged at full power to meet the demand for rapid charging of the battery during parking power generation. Therefore, the VCU will send a message to the BMS to indicate whether the actual parking power generation is on. After receiving the signal, the BMS will switch the battery self-heating cutoff temperature to a higher temperature point that can achieve full power generation performance (e.g., 20℃) to allow the range extender to generate power quickly. At the same time, the VCU will determine and compensate for the power consumption of battery self-heating based on the status of the battery self-heating contactor to ensure the battery charging speed.

[0090] Step S10 is followed by the following steps:

[0091] Step S15, which runs synchronously with step S11, involves the VCU issuing a start command for the range extender to the GCU.

[0092] Step S16: The GCU controls the range extender to start;

[0093] It should be noted that...

[0094] The specific working method is described below using specific embodiments:

[0095] Example 1:

[0096] The parking power generation function described in this invention is set by the user on the central control screen MP5. It is off by default. After the user selects to enable it, the MP5 will forward the parking power generation start-up request signal to the power CAN through the gateway. After receiving the parking power generation start-up signal from the MP5, the VCU will determine whether the vehicle status can enable and turn on the parking power generation function.

[0097] Example 2:

[0098] For the power generation requirements of the range extender with parking generator, considering factors such as economy and NVH, three different modes are provided for users to choose from. The modes are "Default", "High Efficiency", and "Speed". Each mode is accompanied by text prompts, as follows:

[0099] High-efficiency mode: slower power generation, economical and environmentally friendly.

[0100] Speed ​​mode: Fastest power generation speed, but with higher noise level.

[0101] Default mode: generates electricity faster, but is slightly noisier.

[0102] The differences between the three modes are as follows:

[0103] High-efficiency mode: Optimal power generation economy. The system will select the optimal power generation efficiency range of the range extender (the highest selectable point of oil-to-electricity conversion rate) based on the current battery capacity, and the power generation rate will be dynamically and automatically adjusted.

[0104] Speed ​​Mode: VCU Requested Maximum Power = Min (Battery Continuous Charging Power Limit, Range Extender Continuous Maximum Power Generation Limit). The higher the power generation rate percentage selected on the MP5 terminal, the greater the power generation requested by the VCU from the range extender, and the corresponding NVH of the vehicle will also be reduced (engine noise will be louder). If the user wants to charge the battery at the fastest speed, simply set the parking power generation rate to the maximum.

[0105] Default mode: The range extender's power output is determined by balancing power generation efficiency, power generation rate, and overall vehicle NVH performance. In default mode, the range extender's power output requirement is not very high.

[0106] Example 3:

[0107] The VCU calculates the remaining time required to fully charge the battery based on the difference between the target SOC and the current actual SOC, combined with the actual power generation of the range extender. This calculation is then sent to the bus, forwarded by the gateway to the vehicle's CAN bus, and parsed and displayed in real-time on the MP5 terminal. The calculation formula is as follows:

[0108] t = (Target SOC value - Current SOC value) * Battery capacity / Actual power generation of the range extender.

[0109] Example 4:

[0110] After the air conditioning / heating (hereinafter referred to as "AC / PTC") is turned on, power compensation is performed to ensure the charging speed of the battery. If the driver turns on AC / PTC during the parking power generation period, the VCU should compensate for this part of the power consumption. The VCU determines whether the air conditioning or heating is working by judging the engagement status of the air conditioning compressor or PTC relay. If it is working, the power generation request sent to the range extender needs to be increased by the steady-state power consumption of the air conditioning or heating. The power generation request sent by the VCU to the range extender shall not exceed the maximum power request of the VCU.

[0111] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other situations without modification, are all within the protection scope of the present invention.

Claims

1. A method for controlling the power generation during parking in a range-extended electric vehicle, characterized in that, Includes the following steps: Step S10: Turn on the parking power generation function; Step S20: Determine whether the MP5 terminal selects the high-efficiency mode. If yes, proceed to step S21; otherwise, proceed to step S22. Step S21: Based on the battery charging power limit, the VCU selects the optimal hybrid power conversion efficiency point from the range extender efficiency map, requests the range extender to generate electricity, and then proceeds to step S30; Step S22: Determine whether the MP5 terminal selects the "speed" charging mode. If not, proceed to step S23; if so, proceed to step S24; Step S23: The VCU executes the default charging mode, taking into account power generation efficiency, power generation rate, and vehicle NVH performance to determine the power generation power, and then proceeds to step S30; Step S24: Further select different power generation speeds at the MP5 terminal; Step S25: The VCU converts the power value to the corresponding power value under the maximum requestable power generation; Step S30: The VCU calculates the range extender's requested power P based on the current parking power generation mode. base； Step S40: Determine whether the battery self-heating contactor is in the closed state; otherwise, execute P1=P base If so, then execute P1=P base +2.7kW, then proceed to step S50; in step S50, determine whether the air conditioner or heater is in operation. If not, execute P2=P1; if so, execute P2=P1+P AC / PTC Then, proceed to step S60; in step S60, the VCU sends P2 to the GCU, where P2 ≤ Min (maximum power limit for continuous battery charging and maximum power limit for continuous range extender generation).

2. The method for controlling the parking power generation of a range-extended electric vehicle according to claim 1, characterized in that: After step S60, the following steps are set: Step S70, the VCU calculates the time required to fully charge the battery based on the actual power generation of the range extender and the remaining battery charge; Step S80, the MP5 terminal displays the time required to fully charge the remaining battery in real time; Step S90, it is determined whether the vehicle meets any of the following parking charging conditions: (1) Battery SOC>90%; (2) Vehicle speed 1km / h; (3) Gear not in N gear; (4) Parking brake released; (5) Engine abnormally stopped; If yes, the parking power generation ends, otherwise return to step S90 to continue judging the vehicle.

3. The method for controlling the parking power generation of a range-extended electric vehicle according to claim 1, characterized in that: Before step S10, the following steps are set: Step S01, the high voltage of the whole vehicle is ready; Step S02, determine whether the MP5 terminal requests parking power generation. If yes, proceed to step S03; otherwise, return to step S02 and repeat the judgment; Step S03, determine whether the battery SOC is less than 90%, the vehicle speed is less than 1km / h, the gear is in N gear, and the parking brake is in braking state. If yes, proceed to step S10; otherwise, return to step S03 and repeat the judgment; Step S04, run synchronously with step S02, determine whether the cell temperature is lower than the self-heating threshold through BMS. If yes, proceed to step S05; otherwise, return to step S04 and repeat the judgment; Step S05, after a 10s delay, the BMS activates self-heating.

4. The method for controlling the parking power generation of a range-extended electric vehicle according to claim 1, characterized in that: After step S10, the following steps are also included: Step S11, which runs synchronously with step S20, the VCU sends the actual status of the parking power generation to the BMS; Step S12, the BMS determines whether to enable the self-heating temperature switching based on the cell temperature; Step S13, it determines whether the battery has switched the battery self-heating cutoff temperature. If yes, proceed to step S14; otherwise, return to step S12 and repeat the determination; Step S14, the BMS controls the heating film to heat to the cutoff temperature and then stops.

5. The method for controlling the parking power generation of a range-extended electric vehicle according to claim 4, characterized in that: Step S10 is followed by the following steps: Step S15, which runs synchronously with Step S11, where the VCU sends a start command for the range extender to the GCU; Step S16, where the GCU controls the range extender to start.

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