Control method for intelligent generator of commercial vehicle engine

Abstract

The invention discloses a control method for an intelligent generator of a commercial vehicle engine, and relates to the engine control technology, the operation condition of a commercial vehicle is obtained, and if the operation condition is that a battery system breaks down, a preset fault voltage value is output; if the operation condition is that the commercial vehicle is in a brake recovery or sliding state, outputting a preset maximum voltage value; if the operation condition is that the engine is in a shutdown state, outputting a preset standard voltage value; if the operation condition is that the commercial vehicle is in a sudden acceleration state or an engine is in a starting state, outputting a preset minimum voltage value; and if the engine is in the working condition except the four operation working conditions, calculating a power generation target voltage value and a lithium battery charging request target voltage, and taking the larger one of the power generation target voltage value and the lithium battery charging request target voltage as the output voltage of the generator. The working life of the storage battery or the lithium battery can be prolonged, the dynamic property of the engine under the specific working condition is effectively improved, energy is recycled, and kinetic energy loss is reduced.

Description

Technical Field

[0001] The present invention relates to engine control technology, and more specifically, to a control method for an intelligent generator of a commercial vehicle engine. Background Art

[0002] The generators currently installed on commercial vehicle engines have undergone a long period of market verification, and the products are already very mature and reliable. However, the generator is a non-controlled type, and the generator's power generation and speed are fixed, and the change in power generation cannot be controlled, resulting in the following disadvantages: the generator will continue to generate electricity when the engine is running, and due to changes in speed, the power generation will also change, and ultimately the power generation voltage will also fluctuate. In recent years, the power of electrical equipment installed in commercial vehicles has been increasing, and voltage fluctuations will affect the working performance and service life of electrical equipment. In order to avoid the shortcomings of non-controlled generators, China has been gradually researching and developing intelligent generators, but there is currently a lack of relevant control methods for intelligent generators. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a control method for an intelligent generator of a commercial vehicle engine in view of the deficiencies in the prior art.

[0004] The control method of a commercial vehicle engine intelligent generator of the present invention obtains the operating conditions of the commercial vehicle and controls the output voltage of the generator according to the operating conditions; specifically, the method comprises:

[0005] If the operating condition is a battery system failure, a preset fault voltage value is output as the output voltage of the generator;

[0006] If the operating condition is that the commercial vehicle is in a braking recovery or coasting state, a preset maximum voltage value is output as the output voltage of the generator;

[0007] If the operating condition is that the engine is in a shutdown state, a preset standard voltage value is output as the output voltage of the generator;

[0008] If the operating condition is that the commercial vehicle is in a rapid acceleration state or the engine is in a starting state, a preset minimum voltage value is output as the output voltage of the generator;

[0009] If the engine is in an operating condition other than the above four operating conditions, the power generation target base1 value and the power generation target base2 value are calculated according to the current SOC of the battery, the current SOH of the battery, the actual vehicle speed, the reference temperature of the power generation voltage and the engine combustion efficiency of the commercial vehicle, and one of the power generation target base1 value and the power generation target base2 value is selected as the power generation target voltage value according to the model of the commercial vehicle; the lithium battery charging request target voltage is obtained, and the larger voltage value of the power generation target voltage value and the lithium battery charging request target voltage is taken as the output voltage of the generator.

[0010] Preferably, the power generation target base1 value is calculated as follows:

[0011] The optimal SOC setting base value is calibrated according to the actual vehicle speed and the power generation voltage reference temperature. At the same time, the SOC correction value is queried from the battery aging degree correction curve according to the current SOH of the battery. The SOC correction value is summed with the optimal SOC setting base value to obtain the optimal SOC setting value after aging correction; the optimal SOC setting value is subtracted from the current SOC of the battery to obtain the SOC difference, and the power generation target base1 value is calibrated according to the SOC difference and the engine combustion efficiency.

[0012] Preferably, the power generation target base2 value is calculated as follows:

[0013] According to the current SOH of the battery, the SOC correction value is queried from the battery aging correction curve, the SOC correction value is summed with the current SOC of the battery, and the target voltage setting base value of the intelligent generator is calibrated by the reference temperature of the power generation voltage and the result of the sum calculation; according to the engine combustion efficiency, the first correction value of the power generation voltage is queried from the engine combustion efficiency correction curve, and according to the actual vehicle speed, the second correction value of the power generation voltage is queried from the vehicle speed correction curve, the target voltage setting base value of the intelligent generator is added to the first correction value of the power generation voltage, and then the addition result is added to the second correction value of the power generation voltage to obtain the power generation target base2 value.

[0014] Preferably, the battery system fault includes a battery IBS sensor fault, a lithium battery fault and an intelligent generator fault.

[0015] Preferably, the battery IBS sensor failure is determined in the following manner:

[0016] Whether the battery IBS sensor is in a fault state is determined according to the battery sensor fault code, the battery fault code, the battery power abnormal alarm status code, the battery sensor LIN communication fault code, and the initialization status code. If any of the battery sensor fault code, the battery fault code, the battery power abnormal alarm status code, and the battery sensor LIN communication fault code is the same as the corresponding preset judgment code, it is determined that the battery IBS sensor is faulty; or if the initialization status code is different from the corresponding preset status code, it is determined that the battery IBS sensor is faulty.

[0017] Preferably, the lithium battery failure is determined by:

[0018] Whether the lithium battery is in a faulty state is judged according to the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell pressure difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm. If any of the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell pressure difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm is the same as the corresponding set alarm value, then it is judged that the lithium battery is faulty.

[0019] Preferably, the smart generator failure is determined by:

[0020] Whether the smart generator is in a faulty state is determined based on the smart generator mechanical fault alarm and the smart generator electrical fault alarm. If any of the smart generator mechanical fault alarm and the smart generator electrical fault alarm is the same as the corresponding set alarm value, it is determined that the smart generator is faulty.

[0021] Preferably, the power generation voltage reference temperature is obtained by:

[0022] A sampling temperature is selected according to the battery type of the commercial vehicle, and a temperature closest to the reference temperature is selected from the sampling temperature and the ambient temperature according to a preset reference temperature as a reference temperature for the power generation voltage.

[0023] Preferably, the sampling temperature includes the battery temperature and the lithium battery temperature; when the battery type of the commercial vehicle is a lithium battery, the sampling temperatures of sampling point two and sampling point three of the lithium battery are obtained, and the maximum value of the two sampling points is taken as the lithium battery temperature.

[0024] Preferably, the actual vehicle speed and engine combustion efficiency both need to be filtered.

[0025] Beneficial Effects

[0026] The advantages of the present invention are as follows: the present invention combines the current state information of the battery and the current operating parameters of the engine, and adopts the corresponding power generation target voltage value as the output voltage of the generator under different operating conditions of the commercial vehicle to control the operation of the generator, so that the generator can operate more intelligently and stably, and the output electrical signal has smaller fluctuations, which can increase the service life of the battery or lithium battery, and effectively improve the power of the engine under specific operating conditions, recover energy to reduce kinetic energy loss, and reduce the fuel consumption of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic flow chart of the control method of the present invention;

[0028] Figure 2 It is a schematic diagram of the battery IBS sensor fault judgment process of the present invention;

[0029] Figure 3 This is a schematic diagram of the lithium battery fault judgment process of the present invention;

[0030] Figure 4 It is a schematic diagram of the intelligent generator fault judgment process of the present invention;

[0031] Figure 5 It is a schematic diagram of the braking recovery and sliding state judgment process of the present invention;

[0032] Figure 6 It is a schematic diagram of the rapid acceleration state judgment process of the present invention;

[0033] Figure 7 A schematic diagram of a process flow for obtaining a reference temperature for a power generation voltage according to the present invention;

[0034] Figure 8 It is a schematic diagram of the calculation process of the power generation target base1 value of the present invention;

[0035] Fig. 9 It is a schematic diagram of the calculation process of the power generation target base2 value of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with the embodiments, but it does not constitute any limitation to the present invention. Any limited number of modifications made by anyone within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0037] See also Figure 1-Figure 9 The present invention provides a control method for a commercial vehicle engine intelligent generator, which obtains the operating conditions of the commercial vehicle and controls the output voltage of the generator according to the operating conditions. Specifically:

[0038] 1. If the operating condition is a battery system failure, the preset fault voltage value is output as the output voltage of the generator.

[0039] Among them, the battery system failure in this embodiment mainly includes battery IBS sensor failure, lithium battery failure and intelligent generator failure.

[0040] like Figure 2 As shown in the figure, the judgment method of battery IBS sensor failure is:

[0041] Whether the battery IBS sensor is in a faulty state is determined according to the battery sensor fault code, battery fault code, battery power abnormal alarm status code, battery sensor LIN communication fault code, and initialization status code. If any battery sensor fault code, battery fault code, battery power abnormal alarm status code, and battery sensor LIN communication fault code are the same as the corresponding preset judgment code, it is determined that the battery IBS sensor is faulty, or if the initialization status code is different from the corresponding preset status code, it is determined that the battery IBS sensor is faulty.

[0042] like Figure 3 As shown in the figure, the judgment method of lithium battery failure is:

[0043] Whether the lithium battery is in a faulty state is determined according to the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell voltage difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm. If any of the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell voltage difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm is the same as the corresponding set alarm value, it is determined to be a lithium battery fault.

[0044] like Figure 4 As shown in the figure, the judgment method of intelligent generator failure is:

[0045] Whether the smart generator is in a faulty state is determined based on the smart generator mechanical fault alarm and the smart generator electrical fault alarm. If any of the smart generator mechanical fault alarm and the smart generator electrical fault alarm is the same as the corresponding set alarm value, it is determined that the smart generator is faulty.

[0046] 2. If the operating condition is that the commercial vehicle is in a braking recovery or coasting state, but the battery system has no faults, the preset maximum voltage value is output as the output voltage of the generator.

[0047] Among them, for braking recovery and sliding state, such as Figure 5As shown, whether the vehicle is currently in a coasting recovery state or a braking recovery state is determined based on six parameters: the amount of cyclic injection, the actual vehicle speed, the current gear position, the neutral state, the current battery SOC, and the braking state.

[0048] 3. If the operating condition is that the engine is in a shutdown state, but the battery system has no faults, the preset standard voltage value is output as the output voltage of the generator.

[0049] 4. If the operating condition is that the commercial vehicle is in rapid acceleration or the engine is in starting state, but the battery system has no faults, the preset minimum voltage value is output as the output voltage of the generator.

[0050] Among them, for the rapid acceleration state, such as Figure 6 As shown, whether the current state is in a rapid acceleration state is determined based on the throttle opening and the preset upper and lower limits.

[0051] 5. If the engine is in a condition other than the above four operating conditions, the power generation target base1 value and the power generation target base2 value are calculated according to the current SOC of the battery, the current SOH of the battery, the actual vehicle speed, the reference temperature of the power generation voltage and the engine combustion efficiency of the commercial vehicle, and one of the power generation target base1 value and the power generation target base2 value is selected as the power generation target voltage value according to the model of the commercial vehicle. The lithium battery charging request target voltage is obtained, and the larger voltage value of the power generation target voltage value and the lithium battery charging request target voltage value is taken as the output voltage of the generator.

[0052] That is, by combining the current status information of the battery and the current operating parameters of the engine, the corresponding target voltage value for power generation is used as the output voltage of the generator under different operating conditions of the commercial vehicle to control the operation of the generator, so that the generator can operate more intelligently and stably, and the output electrical signal has smaller fluctuations, which can increase the service life of the battery or lithium battery, and effectively improve the power of the engine under specific operating conditions, recover energy to reduce kinetic energy loss, and reduce the vehicle's fuel consumption.

[0053] In this embodiment, both the actual vehicle speed and the engine combustion efficiency need to be processed by filtering, and the filtering method can adopt any technology in the prior art.

[0054] like Figure 7 As shown, the reference temperature of the power generation voltage in this embodiment is obtained by the following method:

[0055] Select the sampling temperature according to the battery type of the commercial vehicle, and select the sampling temperature and the ambient temperature that is closest to the reference temperature as the reference temperature for the power generation voltage according to the preset reference temperature. More specifically, the sampling temperature includes the battery temperature and the lithium battery temperature; when the battery type of the commercial vehicle is a lithium battery, obtain the sampling temperatures of sampling point two and sampling point three of the lithium battery, and take the maximum value of the two sampling points as the lithium battery temperature. Since the battery types on commercial vehicles include storage batteries (such as lead-acid batteries) and lithium batteries, the storage batteries are often a whole, and the temperature rise is relatively uniform everywhere, so a single-point sampling temperature is sufficient. However, lithium batteries are composed of multiple single-cell lithium batteries, so their temperature generally needs to be adopted at multiple points. Therefore, when the battery of the commercial vehicle is a lithium battery, this embodiment selects a sampling point with a high temperature as the lithium battery temperature, which can better reflect the working condition of the lithium battery.

[0056] For the calculation of the power generation target base1 value, such as Figure 8 As shown, the specific method is:

[0057] According to the actual vehicle speed and the reference temperature of the power generation voltage, the optimal SOC setting base value is calibrated from the base value curve of vehicle speed-power generation voltage reference temperature-SOC. At the same time, according to the current SOH of the battery, the SOC correction value is queried from the battery aging correction curve, and the SOC correction value and the optimal SOC setting base value are summed to obtain the optimal SOC setting value after aging correction; the optimal SOC setting value and the current SOC of the battery are subtracted to obtain the SOC difference, and the power generation target base1 value is calibrated from the SOC difference-combustion efficiency curve through the SOC difference and the engine combustion efficiency. Among them, the curves described in this article are all obtained by calibrating the engine on the test bench.

[0058] like Fig. 9 As shown, the calculation method of the power generation target base2 value is:

[0059] According to the current SOH of the battery, the SOC correction value is queried from the battery aging correction curve, and the SOC correction value is summed with the current SOC of the battery. The target voltage setting base value of the intelligent generator is calibrated by the reference temperature of the power generation voltage and the result of the sum calculation. According to the engine combustion efficiency, the first correction value of the power generation voltage is queried from the engine combustion efficiency correction curve, and according to the actual vehicle speed, the second correction value of the power generation voltage is queried from the vehicle speed correction curve. After adding the target voltage setting base value of the intelligent generator to the first correction value of the power generation voltage, the addition result is added to the second correction value of the power generation voltage to obtain the power generation target base2 value.

[0060] Two power generation target base values ​​are obtained through different calculation methods, and the power generation target base value is selected based on the different vehicle models, so that the final selected power generation target voltage value matches it, effectively improving the matching degree between the generator and the battery on the relevant vehicle model and achieving better charging function.

[0061] As for the lithium battery charging request target voltage, the specific method is: according to the three parameters of the state of the T15 sensor, the current SOC of the battery, and the cumulative time limit of the battery SOC calibration, the lithium battery SOC calibration voltage demand state and the lithium battery SOC calibration cumulative running time are obtained through the lithium battery SOC calibration demand logic module, and the lithium battery SOC calibration voltage demand state is used to select whether the battery demand is zero (that is, no charging is required) or the lithium battery SOC calibration voltage demand calibration value, and then the selection result and the BMS request charging voltage value are calculated to take the larger value, and finally, according to the battery type carried by different models, the output of zero value or the result after the larger calculation is selected as the lithium battery charging request target voltage. That is, if the battery type is a storage battery, the lithium battery charging request target voltage output is zero value, otherwise when the lithium battery needs to be charged, the result after the larger calculation is used as the lithium battery charging request target voltage.

[0062] The above is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A control method for a commercial vehicle engine intelligent generator, characterized in that: Obtain the operating conditions of the commercial vehicle, and control the output voltage of the generator according to the operating conditions; specifically: If the operating condition is a battery system failure, a preset fault voltage value is output as the output voltage of the generator; If the operating condition is that the commercial vehicle is in a braking recovery or coasting state, a preset maximum voltage value is output as the output voltage of the generator; If the operating condition is that the engine is in a shutdown state, a preset standard voltage value is output as the output voltage of the generator; If the operating condition is that the commercial vehicle is in a rapid acceleration state or the engine is in a starting state, a preset minimum voltage value is output as the output voltage of the generator; If the engine is in an operating condition other than the above four operating conditions, the power generation target base1 value and the power generation target base2 value are calculated according to the current SOC of the battery, the current SOH of the battery, the actual vehicle speed, the reference temperature of the power generation voltage and the engine combustion efficiency of the commercial vehicle, and one of the power generation target base1 value and the power generation target base2 value is selected as the power generation target voltage value according to the model of the commercial vehicle; the lithium battery charging request target voltage is obtained, and the larger voltage value of the power generation target voltage value and the lithium battery charging request target voltage is taken as the output voltage of the generator.

2. The control method of a commercial vehicle engine intelligent generator according to claim 1, characterized in that: The calculation method of the power generation target base1 value is: The optimal SOC setting base value is calibrated according to the actual vehicle speed and the power generation voltage reference temperature. At the same time, the SOC correction value is queried from the battery aging degree correction curve according to the current SOH of the battery. The SOC correction value is summed with the optimal SOC setting base value to obtain the optimal SOC setting value after aging correction; the optimal SOC setting value is subtracted from the current SOC of the battery to obtain the SOC difference, and the power generation target base1 value is calibrated according to the SOC difference and the engine combustion efficiency.

3. The control method of a commercial vehicle engine intelligent generator according to claim 1, characterized in that: The calculation method of the power generation target base2 value is: According to the current SOH of the battery, the SOC correction value is queried from the battery aging correction curve, the SOC correction value is summed with the current SOC of the battery, and the target voltage setting base value of the intelligent generator is calibrated by the reference temperature of the power generation voltage and the result of the sum calculation; according to the engine combustion efficiency, the first correction value of the power generation voltage is queried from the engine combustion efficiency correction curve, and according to the actual vehicle speed, the second correction value of the power generation voltage is queried from the vehicle speed correction curve, the target voltage setting base value of the intelligent generator is added to the first correction value of the power generation voltage, and then the addition result is added to the second correction value of the power generation voltage to obtain the power generation target base2 value.

4. The control method of a commercial vehicle engine intelligent generator according to claim 1, characterized in that: The battery system failure includes battery IBS sensor failure, lithium battery failure and smart generator failure.

5. The control method of a commercial vehicle engine intelligent generator according to claim 4, characterized in that: The method for judging the failure of the battery IBS sensor is as follows: Whether the battery IBS sensor is in a fault state is determined according to the battery sensor fault code, the battery fault code, the battery power abnormal alarm status code, the battery sensor LIN communication fault code, and the initialization status code. If any of the battery sensor fault code, the battery fault code, the battery power abnormal alarm status code, and the battery sensor LIN communication fault code is the same as the corresponding preset judgment code, it is determined that the battery IBS sensor is faulty; or if the initialization status code is different from the corresponding preset status code, it is determined that the battery IBS sensor is faulty.

6. The control method of a commercial vehicle engine intelligent generator according to claim 4, characterized in that: The method for judging the lithium battery failure is as follows: Whether the lithium battery is in a faulty state is judged according to the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell pressure difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm. If any of the charging overtemperature alarm, charging low temperature alarm, battery fault level, battery cell temperature difference too high alarm, battery cell pressure difference too high alarm, SOC low alarm, single cell overvoltage alarm, single cell undervoltage alarm, battery pack overvoltage alarm, charging overcurrent alarm, and discharge overcurrent alarm is the same as the corresponding set alarm value, then it is judged that the lithium battery is faulty.

7. The control method of a commercial vehicle engine intelligent generator according to claim 4, characterized in that: The method for judging the fault of the intelligent generator is as follows: Whether the smart generator is in a faulty state is determined based on the smart generator mechanical fault alarm and the smart generator electrical fault alarm. If any of the smart generator mechanical fault alarm and the smart generator electrical fault alarm is the same as the corresponding set alarm value, it is determined that the smart generator is faulty.

8. The control method of a commercial vehicle engine intelligent generator according to claim 1, characterized in that: The reference temperature of the power generation voltage is obtained by: A sampling temperature is selected according to the battery type of the commercial vehicle, and a temperature closest to the reference temperature is selected from the sampling temperature and the ambient temperature according to a preset reference temperature as a reference temperature for the power generation voltage.

9. A control method for a commercial vehicle engine intelligent generator according to claim 8, characterized in that: The sampling temperature includes the battery temperature and the lithium battery temperature; when the battery type of the commercial vehicle is a lithium battery, the sampling temperatures of sampling point two and sampling point three of the lithium battery are obtained, and the maximum value of the two sampling points is taken as the lithium battery temperature.

10. The control method of a commercial vehicle engine intelligent generator according to claim 1, characterized in that: The actual vehicle speed and engine combustion efficiency both need to be processed by filtering.

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