Endurance mileage algorithm for extended-range electric vehicle

Abstract

The invention relates to the technical field of electric vehicles, in particular to an extended-range electric vehicle endurance mileage algorithm, which comprises the following steps of: S1, aiming at different batteries, obtaining real-time available residual electric quantity Ebatteriaval of the batteries; the method comprises the following steps: S1, starting a VCU (vehicle control unit), S2, after the VCU is initialized, reading data of a previous driving cycle in an EEPROM (electrically erasable programmable read-only memory), and calculating average power consumption data per hundred kilometers and pure electric endurance mileage, S3, carrying out upper and lower limit value processing on the filtered pure electric endurance mileage, S4, calculating oil-electricity comprehensive endurance mileage, S5, carrying out limit value processing on the oil-electricity comprehensive endurance mileage again, and S5, carrying out limit value processing on the oil-electricity comprehensive endurance mileage. The problem that the driving mileage is calculated inaccurately at the present stage, if a driver does not supplement energy in time when a charging pile is far away from a gas station, the vehicle may lie down due to no oil and no electricity, and normal vehicle use of a user is affected is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to an algorithm for the range of an extended-range electric vehicle. Background Art

[0002] Compared with pure electric electric vehicles, extended-range electric vehicles have less range anxiety. When the battery is low, there is no need to worry about insufficient vehicle range. The vehicle can enter extended-range mode to allow the range extender to generate electricity to power the electric drive system to drive the vehicle to continue driving, and the range in extended-range mode is longer than that in pure electric mode.

[0003] The range calculation of extended-range electric vehicles has more influencing variables than that of pure electric vehicles. The power generation operating conditions after the range extender APU is started correspond to different power generation efficiencies, which means that the same liter of oil converts different amounts of electricity through the APU, and therefore the range is also different. If there is a large deviation in the range calculation, then when the charging pile and the gas station are far apart, the charging locations are far apart. If the driver fails to recharge in time, the vehicle may run out of oil and electricity, causing the vehicle to break down, affecting the user's normal use of the vehicle. Summary of the invention

[0004] The present invention provides an extended-range electric vehicle cruising range algorithm, which maps and searches for the oil-to-electricity conversion ratio of the APU by calculating the required average power generation power of the APU, thereby achieving more accurate pure oil cruising range calculation, and calculates the total cruising range by calculating the real-time power consumption of the whole vehicle as well as the remaining power and remaining oil. The 19+1 moving average algorithm is used to dynamically and in real time update the remaining pure electric cruising range and the comprehensive oil-to-electricity cruising range of the whole vehicle, thereby providing a more accurate reference for the whole vehicle cruising range for the customer driving, and avoiding the risk of the vehicle breaking down due to the user's failure to replenish the energy in time.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: an extended-range electric vehicle cruising range algorithm, specifically comprising the following steps:

[0006] Step S1, for different batteries, when the battery power is different, calibrate the rated power Enor of the initial battery pack and the lower limit SOC of the battery discharge allowed, and obtain the real-time available remaining power Ebatteryaval of the battery through the battery management unit;

[0007] Step S2, after the vehicle is powered on and VCU is initialized, after reading the data of the previous driving cycle in the EEPROM, the VCU starts to calculate the real-time vehicle power consumption of the current driving cycle, accumulates the vehicle running mileage, and simultaneously integrates the actual discharge power of the electric drive in real time to obtain the cumulative power consumption under the accumulated mileage, and calculates the average power consumption per 100 kilometers, and uses the available remaining power calculated in step S1 to calculate the pure electric cruising range, and stores the updated power consumption data per 100 kilometers and the calculated pure electric cruising range in real time in the EEPROM;

[0008] Step S3, performing upper and lower limit processing on the filtered pure electric cruising range to prevent the real-time calculated cruising range from exceeding the theoretical range, so as to read the pure electric cruising range data of the previous driving cycle for initial display after the vehicle is powered off and then powered on;

[0009] Step S4, calculating the cruising range that can be supported by the remaining pure fuel based on the remaining fuel volume and the electricity consumption per 100 kilometers, and adding the pure electric cruising range and the pure fuel cruising range to finally obtain the comprehensive fuel-electric cruising range;

[0010] Step S5, the combined oil-electric cruising range is again limited to prevent abnormal data calculation results, and the external instrument is displayed in real time after filtering.

[0011] It is further shown that the available remaining battery SOCaval is obtained by estimating the external SOCact in real time through the battery management unit, and then subtracting the lower discharge limit SOCmin of the battery, which is allowed, and then multiplying it by the actual health of the battery SOH and the initially calibrated battery power to obtain the real-time available remaining battery power Ebatteryaval. For the calculation of the available remaining battery SOCaval, in order to prevent the real-time SOCact sent by the BMS from fluctuating, when calculating the cruising range, the VCU will perform low-pass filtering on the SOC to eliminate high-frequency noise interference. At the same time, in order to prevent the actual SOC of the battery under extreme working conditions from being lower than the lower discharge limit SOCmin allowed for the battery, resulting in a negative value in the calculated remaining available SOC, the larger value between the available remaining SOC and 0 is taken to prevent the available remaining SOC from having a negative value, which will cause the calculated remaining cruising range to be abnormal.

[0012] It is further defined that in step S2, the pure electric range of independent discharge of the power battery is calculated using the available remaining power calculated in real time in step 1 and the real-time updated power consumption data per 100 kilometers. In order to make the pure electric range with higher power closer to the ideal initial value of vehicle range, the pure electric range under high SOC is transitionally processed to improve the stability and rationality of the pure electric range calculation under high SOC. The measured data based on the bench test cycle is multiplied by the ratio of the real-time available remaining SOC to the available SOC under full charge, and then multiplied by the battery health SOH to obtain the transition proportion of the pure electric range under high SOC. The SOC range of 80%-100% is set for data transition mixing, and the transition proportion coefficient of the SOC range of 80%-100% is linearly interpolated to finally obtain the pure electric range EVRange of independent discharge of the remaining power of the power battery.

[0013] Further limitation is to identify the plug-in charging and non-plug-in conditions, and adopt different filtering time constants for the pure electric range data. Since the SOC changes rapidly during charging, a smaller pure electric range filtering time constant is set to synchronize the battery power with the actual range more quickly. The pure electric range filtering time constant for the charging condition is set to 0.2s, and the SOC change in the driving state is relatively smoother, and the pure electric range display should also be smoother, so the pure electric range filtering time constant for the driving condition is set to 10s.

[0014] It is further defined that the data of the previous driving cycle in the EEPROM in step S2 is to read the electric consumption value per 100 kilometers of the previous driving cycle, and to perform a rationality check on the electric consumption value, to set an upper limit and a lower limit of the electric consumption per 100 kilometers, and when the electric consumption value per 100 kilometers of the previous driving cycle is higher than the upper limit or lower than the lower limit, the average value based on the user's actual road driving data is used as the initial electric consumption value per 100 kilometers of the current driving cycle. If the electric consumption value per 100 kilometers of the previous driving cycle read is within the upper and lower limits, the electric consumption value per 100 kilometers of the previous driving cycle read is directly adopted as the initial value of the initial electric consumption per 100 kilometers of the current driving cycle.

[0015] It is further defined that the pure fuel cruising range described in step S4 should be mapped to the oil-to-electricity conversion ratio according to the power consumption level per 100 kilometers and the actual power generation power of the APU, and the actual oil consumption per 100 kilometers should be obtained by dynamic table lookup. The remaining oil volume can be obtained by looking up the table through the oil level sensor resistance value emitted by the instrument. For the calculation of the actual oil-to-electricity conversion ratio of the APU, the required driving time T1km and the accumulated power consumption Etotal for the past kilometer should be accumulated first. The accumulated power consumption calculation formula is as follows:

[0016] Etotal=Eesad+Edcdc+Ehvac+Edcac+Epto, Eesad, Edcdc, Ehvac, Edcac and Epto represent the power consumption of electric drive, DC-DC converter, thermal management system, on-board inverter and upper installation respectively. The calculation formula of APU average power generation power Pavgapu is Pavgapu=Etotal / T1km. The average power generation power of APU is used to find the oil-to-electricity conversion ratio of APU, and then the average fuel consumption of APU at the power consumption level of 100 kilometers is obtained. Then the remaining available fuel is divided by the average fuel consumption and multiplied by 100 to get the pure fuel range.

[0017] Further limitation is that it is necessary to decide whether to directly use the average power consumption as the average power generation power of the required APU based on the difference between the target SOC and the actual SOC. If the difference between the target SOC and the actual SOC is greater than 2%, then in addition to meeting the power demand of the electric drive, the APU also needs to replenish the battery. Therefore, at this time, the amount of power required to compensate for the difference between the target SOC and the actual SOC should be compensated. The power calculation formula for replenishing the battery is: SOCErr=SOCtarget-SOCactual, EbatteryCom=SOCErr*Ebattery, where Ebattery is the full-charged battery energy, and EbatteryCom is the supplementary energy required for the battery to reach the target SOC. Therefore, the average power generation power calculation of the APU needs to add EbatteryCom, and the calculation formula is: Etotal=Eesad+Edcdc+Ehvac+Edcac+Epto+EbatteryCom, and then the total power consumption is divided by T1km to obtain the average power generation power of the APU required, and then the same algorithm is used to calculate the pure oil range.

[0018] It is further limited that for pure electric cruising range, each time the VCU is powered on and initialized, the pure electric cruising range data stored in the previous driving cycle must be read for the instrument cruising range display just after power-on, and after 1 second, it will switch to the real-time pure electric cruising range of this driving cycle.

[0019] The beneficial effects of adopting the above technical solution are:

[0020] The present invention calculates the required APU average power generation to map and search the APU's oil-to-electricity conversion ratio, thereby achieving more accurate calculation of pure oil range, and calculates the total range by calculating the real-time power consumption of the vehicle as well as the remaining power and remaining oil. The moving average algorithm is used to dynamically and in real time update the vehicle's remaining pure electric range and oil-to-electricity combined range, thereby providing customers with a more accurate reference for the vehicle's range and avoiding the risk of the vehicle breaking down due to users' failure to replenish energy in a timely manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The algorithm architecture diagram of the present invention is

[0022] Figure 2 This is a flow chart of the battery life algorithm of the present invention. DETAILED DESCRIPTION

[0023] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0024] like Figure 1-Figure 2 As shown, the present invention is an extended-range electric vehicle range algorithm, which maps and searches for the oil-to-electricity conversion ratio of the APU by calculating the required average power generation power of the APU, thereby achieving more accurate pure oil range calculation, and calculates the total range by calculating the real-time power consumption of the whole vehicle as well as the remaining power and remaining oil. The 19+1 moving average algorithm is used to dynamically and in real time update the remaining pure electric range and the oil-to-electricity combined range of the whole vehicle, thereby providing customers with a more accurate reference for the whole vehicle range and avoiding the risk of the vehicle breaking down due to the user's failure to replenish the energy in time.

[0025] Specifically, Figure 1 and Figure 2 As shown, the specific steps include:

[0026] Step S1, for different batteries matched with different models, when the battery power is different, it is necessary to calibrate the initial battery pack rated power Enor and the lower limit of battery discharge allowed SOC (such as 15%), and use the battery management unit to estimate the external SOCact in real time, subtract the lower limit of battery discharge allowed SOCmin, and get the available remaining battery SOCaval, and then multiply it by the actual health of the battery SOH and the initial calibrated battery power to get the real-time available remaining battery power Ebatteryaval, the calculation formula is SOCaval = SOCact-SOCmin, Ebatteryava l=Ebattery*SOCaval*SOH;In the calculation of available remaining battery SOCaval, in order to prevent the real-time SOC sent by BMS from fluctuating, when calculating the cruising range, VCU will perform low-pass filtering on SOC to eliminate high-frequency noise interference. At the same time, in order to prevent the actual SOC of the battery under extreme working conditions from being lower than the lower limit of the battery discharge allowed SOCmin (such as 15%), resulting in a negative value in the calculated remaining available SOC, the larger value between the available remaining SOC and 0 is taken to prevent the available remaining SOC from being negative, resulting in abnormalities in the calculated remaining cruising range;

[0027] Step S2: After the vehicle is powered on and the VCU is initialized, the power consumption per 100 kilometers value of the previous driving cycle is first read, and the power consumption value is checked for rationality, and an upper limit (such as 100kWh / 100km) and a lower limit (such as 5kWh / 100km) of the power consumption per 100 kilometers are set. When the power consumption per 100 kilometers value of the previous driving cycle is higher than the upper limit or lower than the lower limit, the average value (such as 50kWh / 100km) based on the user's actual road driving data is used as the initial power consumption per 100 kilometers replacement value of the current driving cycle. If the power consumption per 100 kilometers value of the previous driving cycle read is within the upper and lower limits, the power consumption per 100 kilometers value of the previous driving cycle read is directly used as the replacement value. The initial 100km power consumption of this driving cycle is the initial value. After reading the data of the previous driving cycle in the EEPROM (generally 1S), the VCU starts to calculate the real-time vehicle power consumption of this driving cycle, accumulates the vehicle mileage, and simultaneously integrates the actual discharge power of the electric drive in real time to obtain the cumulative power consumption under the cumulative mileage. The cumulative mileage threshold is set to 1Km. When it reaches 1km, the cumulative power consumption of the electric drive is reset to zero. The 100km power consumption of the first 19km is multiplied by 19km to obtain the cumulative power consumption of the first 19km. Then the cumulative power consumption of the first 19km is added to the current cumulative power consumption of 1km to obtain the cumulative total power consumption of the past 20km. The total power consumption of 19+1km is divided by 20 to obtain the average power consumption per 100km calculated based on the past 20km data. After the current cumulative mileage reaches 1km, the updated power consumption per 100km based on the 19+1 moving average algorithm is output, and then the average power consumption per 100km updated last time is used as the calculation basis for the range in the next 1km cumulative mileage. The calculated power consumption per 100km value is low-pass filtered to remove high-frequency noise interference, and the pure electric range is calculated using the available remaining power calculated in step S1. The updated power consumption per 100km data and the calculated pure electric range are stored in real time in the EEPROM so that the vehicle can read the previous driving cycle at any time after powering off and then on. In order to make the pure electric cruising range with a higher power closer to the ideal initial value of the vehicle's cruising range, the pure electric cruising range under high SOC is subjected to transition processing to improve the stability and rationality of the pure electric cruising range calculation under high SOC. Based on the measured data of the bench test cycle, the real-time available remaining SOC is multiplied by the ratio of the available SOC under full power, and then multiplied by the battery health SOH to obtain the transition proportion of the pure electric cruising range under high SOC. The 80% to 100% SOC interval is set for data transition mixing, and the 80% to 100% SOC interval transition proportion coefficient is linearly interpolated to finally obtain the pure electric cruising range EVRange when the remaining power of the power battery is discharged alone;

[0028] For pure electric cruising range, each time the VCU is powered on and initialized, the pure electric cruising range data stored in the previous driving cycle must be read for the instrument cruising range display after power-on. After 1 second, it will switch to the real-time pure electric cruising range of this driving cycle. In order to improve the stability of the pure electric cruising range display, a function for identifying the plug-in charging and non-plug-in conditions is set, and different filtering time constants are used for the pure electric cruising range data. During charging, due to the rapid change of SOC, a smaller pure electric cruising range filtering time constant is set to synchronize the battery power with the actual cruising range faster. The pure electric cruising range filtering time constant of the charging condition is set to 0.2s, while the SOC change in the driving state is relatively smoother, and the pure electric cruising range display should also be more stable, so the pure electric cruising range filtering time constant of the driving condition is set to 10s;

[0029] Step S3, performing upper and lower limit processing on the filtered pure electric cruising range to prevent the real-time calculated cruising range from exceeding the theoretical range, with a minimum of 0 km and a maximum of no more than 1.5 times the theoretical value. After the limit processing, the final pure electric cruising range data is stored in real time to the EEPROM, so that the pure electric cruising range data of the previous driving cycle can be read for initial display after the vehicle is powered off and then powered on;

[0030] Step S4, based on the remaining fuel and the electricity consumption per 100 kilometers, the cruising range supported by the remaining pure fuel is calculated, and the pure electric cruising range and the pure oil cruising range are added to finally obtain the comprehensive oil-electric cruising range. Based on the oil-to-electricity conversion rate of the APU, a high electricity consumption per 100 kilometers means a higher APU required power generation power, and the lower the electricity consumption per 100 kilometers, the lower the required power generation power for the APU. Therefore, for the pure oil cruising range of the extended-range electric vehicle, the oil-to-electricity conversion ratio should be mapped according to the electricity consumption level per 100 kilometers and the actual power generation power of the APU, and the real oil consumption per 100 kilometers should be obtained by dynamic table lookup. The remaining fuel volume is obtained by looking up the table through the oil level sensor resistance value emitted by the instrument, and the oil level is first filtered to prevent the vehicle from bumping or going up and downhill and causing a large fluctuation in the oil level calculation. For the calculation of the actual oil-to-electricity conversion ratio of the APU, the required driving time T1km and the accumulated power consumption Etotal for the past kilometer should be accumulated first. The accumulated power consumption calculation formula is: Etotal=Eesad+Edcdc+Ehv ac+Edcac+Epto, Eesad, Edcdc, Ehvac, Edcac and Epto represent the power consumption of electric drive, DC-DC converter, thermal management system, onboard inverter and upper installation respectively. The calculation formula of APU average power generation Pavgapu is Pavgapu=Etotal / T1km. The average power generation of APU is used to find the oil-to-electricity conversion ratio of APU, and then the average fuel consumption of APU under the power consumption level of 100 kilometers is obtained. Then the remaining available fuel is divided by the average fuel consumption and multiplied by 100 to get the pure oil cruising range. This algorithm can truly and accurately calculate the actual pure oil cruising range. Compared with the fixed algorithm that directly uses the power consumption per 100 kilometers to look up the table to get the fuel consumption per 100 kilometers, the calculation result of pure oil cruising range is closer to the actual cruising range performance of the vehicle, which can also provide users with more accurate cruising range prompt information, so that users can better plan energy replenishment and provide accurate data reference.By adopting the 19+1 moving average algorithm to obtain the actual power consumption per 100 kilometers, data jitter can be prevented and the stability is good. Then the actual pure electric cruising range is calculated, and the accumulated power consumption in the past 1 km is used to calculate the required average APU power generation power, and then a more accurate 100-kilometer fuel consumption is obtained according to the oil-to-electricity conversion ratio, and then the pure oil cruising range is calculated. The pure electric cruising range and the pure oil cruising range are added together to finally obtain the comprehensive oil-electric cruising range. It is necessary to decide whether to directly use the average power consumption as the required average power generation power of the APU based on the difference between the target SOC and the actual SOC. If the difference between the target SOC and the actual SOC is greater than 2%, then in addition to meeting the power demand of the electric drive, the APU also needs to replenish the battery. Therefore, the target SOC and The amount of electricity required to replenish the actual SOC difference is calculated as follows: SOCErr = SOCtarget-SOCactual, EbatteryCom = SOCErr*Ebattery, where Ebattery is the full power of the battery, and EbatteryCom is the supplementary power required for the battery to reach the target SOC. Therefore, the average power generation power calculation of the APU needs to increase EbatteryCo, and the calculation formula is: Etotal = Eesad + Edcdc + Ehvac + Edcac + Epto + EbatteryCom. Then, the total power consumption is divided by T1km to obtain the required average power generation power of the APU, and then the same algorithm is used to calculate the pure oil cruising range;,

[0031] Step S5, finally, the combined oil-electric range is limited again to prevent abnormal data calculation results. After filtering, the external instrument is displayed in real time. Through the moving average algorithm and the cleverly designed pure oil range algorithm, a more accurate calculation of the comprehensive range is achieved.

[0032] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above-mentioned concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. An algorithm for calculating the range of an extended-range electric vehicle, characterized in that: The specific steps include: Step S1, for different batteries, when the battery power is different, calibrate the rated power Enor of the initial battery pack and the lower limit SOC of the battery discharge allowed, and obtain the real-time available remaining power Ebatteryaval of the battery through the battery management unit; Step S2, after the vehicle is powered on and VCU is initialized, after reading the data of the previous driving cycle in the EEPROM, the VCU starts to calculate the real-time vehicle power consumption of the current driving cycle, accumulates the vehicle running mileage, and simultaneously integrates the actual discharge power of the electric drive in real time to obtain the cumulative power consumption under the accumulated mileage, and calculates the average power consumption per 100 kilometers, and uses the available remaining power calculated in step S1 to calculate the pure electric cruising range, and stores the updated power consumption data per 100 kilometers and the calculated pure electric cruising range in real time in the EEPROM; Step S3, performing upper and lower limit processing on the filtered pure electric cruising range to prevent the real-time calculated cruising range from exceeding the theoretical range, so as to read the pure electric cruising range data of the previous driving cycle for initial display after the vehicle is powered off and then powered on; Step S4, calculating the cruising range that can be supported by the remaining pure fuel based on the remaining fuel volume and the electricity consumption per 100 kilometers, and adding the pure electric cruising range and the pure fuel cruising range to finally obtain the comprehensive fuel-electric cruising range; Step S5, the combined oil-electric cruising range is again limited to prevent abnormal data calculation results, and the external instrument is displayed in real time after filtering.

2. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: The battery management unit estimates the external SOCact in real time, subtracts the lower limit of battery discharge SOCmin, and obtains the available remaining battery SOCaval, which is then multiplied by the actual health of the battery SOH and the initially calibrated battery power to obtain the real-time available remaining battery Ebatteryaval. For the calculation of the available remaining battery SOCaval, in order to prevent fluctuations in the real-time SOCact sent by the BMS, the VCU will perform low-pass filtering on the SOC to eliminate high-frequency noise interference when calculating the cruising range. At the same time, in order to prevent the actual SOC of the battery under extreme working conditions from being lower than the lower limit of battery discharge SOCmin, which results in a negative value in the calculated remaining available SOC, the larger value between the available remaining SOC and 0 is taken to prevent the available remaining SOC from having a negative value, which results in abnormalities in the calculated remaining cruising range.

3. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: In step S2, the available remaining power calculated in real time in step 1 and the real-time updated power consumption data per 100 kilometers are used to calculate the pure electric range of the power battery when discharged independently. In order to make the pure electric range with higher power closer to the ideal initial value of vehicle range, the pure electric range under high SOC is transitionally processed to improve the stability and rationality of the pure electric range calculation under high SOC. The measured data based on the bench test cycle is multiplied by the ratio of the real-time available remaining SOC to the available SOC under full charge, and then multiplied by the battery health SOH to obtain the transition proportion of the pure electric range under high SOC. The SOC range of 80%-100% is set for data transition mixing, and the transition proportion coefficient of the SOC range of 80%-100% is linearly interpolated to finally obtain the pure electric range EVRange of the power battery when the remaining power is discharged alone.

4. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: The plug-in charging and non-plug-in conditions are identified, and different filtering time constants are adopted for the pure electric range data. Since the SOC changes rapidly during charging, a smaller pure electric range filtering time constant is set to synchronize the battery power with the actual range more quickly. The pure electric range filtering time constant of the charging condition is set to 0.2s. The SOC change in the driving state is relatively smoother, and the pure electric range display should also be smoother, so the pure electric range filtering time constant of the driving condition is set to 10s.

5. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: In step S2, the data of the previous driving cycle in the EEPROM is read to read the electric consumption value per 100 kilometers of the previous driving cycle, and the electric consumption value is checked for rationality, and an upper limit and a lower limit of the electric consumption per 100 kilometers are set. When the electric consumption value per 100 kilometers of the previous driving cycle is higher than the upper limit or lower than the lower limit, the average value based on the user's actual road driving data is used as the initial electric consumption value per 100 kilometers of the current driving cycle. If the electric consumption value per 100 kilometers of the previous driving cycle read is within the upper and lower limits, the electric consumption value per 100 kilometers of the previous driving cycle read is directly adopted as the initial value of the initial electric consumption per 100 kilometers of the current driving cycle.

6. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: The pure fuel cruising range described in step S4 should be mapped to the oil-to-electricity conversion ratio according to the power consumption level per 100 kilometers and the actual power generation power of the APU, and the actual oil consumption per 100 kilometers should be obtained by dynamic table lookup. The remaining oil volume can be obtained by looking up the table through the oil level sensor resistance value emitted by the instrument. For the calculation of the actual oil-to-electricity conversion ratio of the APU, the required driving time T1km and the accumulated power consumption Etotal for the past kilometer should be accumulated first. The accumulated power consumption calculation formula is as follows: Etotal=Eesad+Edcdc+Ehvac+Edcac+Epto, Eesad , Edcdc, Ehvac, Edcac and Epto represent the power consumption of electric drive, DC-DC converter, thermal management system, on-board inverter and upper installation respectively. The calculation formula of APU average power generation power Pavgapu is Pavgapu=Etotal / T1km. The average power generation power of APU is used to find the oil-to-electricity conversion ratio of APU, and then the average fuel consumption of APU at the power consumption level of 100 kilometers is obtained. Then, the remaining available fuel is divided by the average fuel consumption and multiplied by 100 to get the pure fuel range.

7. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: It is necessary to decide whether to directly use the average power consumption as the required average power generation of the APU based on the difference between the target SOC and the actual SOC. If the difference between the target SOC and the actual SOC is greater than 2%, then in addition to meeting the power demand of the electric drive, the APU also needs to replenish the battery. Therefore, at this time, the amount of power required to compensate for the difference between the target SOC and the actual SOC should be compensated. The power calculation formula for replenishing the battery is: SOCErr=SOCtarget-SOCactual, EbatteryCom=SOCErr*Ebattery, where Ebattery is the full-charged battery energy, and EbatteryCom is the supplementary energy required for the battery to reach the target SOC. Therefore, the average power generation calculation of the APU needs to add EbatteryCo, and the calculation formula is: Etotal=Eesad+Edcdc+Ehvac+Edcac+Epto+EbatteryCom, and then divide the total power consumption by T1km to obtain the required average power generation of the APU, and then use the same algorithm to calculate the pure oil range.

8. The range algorithm of an extended-range electric vehicle according to claim 1, characterized in that: For pure electric range, each time the VCU is powered on and initialized, the pure electric range data stored in the previous driving cycle will be read for the instrument range display after power-on, and after 1 second, it will switch to the real-time pure electric range of this driving cycle.

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