A wireless charging power adjustment method and system for two-wheeled electric vehicles

Abstract

The present application relates to the field of wireless charging technology, and specifically to a wireless charging power adjustment method and system for two-wheeled electric vehicles, the method comprising: obtaining the initial SOC value of the battery before starting charging through the open circuit voltage method; obtaining the input power of the transmitting module at each moment, the output power of the receiving module at each moment, and collecting the voltage, current and temperature of the battery at each moment during the wireless charging process; calculating the temperature rise coefficient at each moment, determining the estimated SOC value and charging efficiency of the battery at each moment; judging the charging stage at each moment; obtaining the adjusted charging power at each moment in the constant current charging stage and the constant voltage charging stage; and adjusting the charging power in real time during the wireless charging process. The present application can dynamically adjust the wireless charging power, improve the efficiency of wireless charging, reduce energy loss, and avoid overcharging of the battery.

Description

Technical Field

[0001] The present application relates to the field of wireless charging technology, and in particular to a wireless charging power regulation method and system for a two-wheeled electric vehicle. Background Art

[0002] Wireless charging is a technology that transmits electrical energy in space. It is a contactless, wireless and flexible charging mode. Its core principle is to convert electrical energy into electromagnetic waves through electromagnetic induction, electromagnetic radiation, electromagnetic resonance and other methods, and then convert them into electrical energy after transmission. This technology eliminates the physical connection limitations of traditional wired charging and improves the convenience and safety of charging.

[0003] The charging process of the battery in a two-wheeled electric vehicle has dynamic characteristics, and its charging demand will change with factors such as the state of charge, temperature, and battery aging. If a fixed charging power mode is used for charging, this mode cannot adapt to the dynamic demand of the battery at different charging stages, which may lead to low charging efficiency, energy waste, and even overcharging, affecting battery life and safety. Summary of the invention

[0004] In order to solve the above technical problems, a wireless charging power adjustment method and system for a two-wheeled electric vehicle are provided to solve the existing problems.

[0005] The solution to the technical problem of the present application is to provide a wireless charging power adjustment method and system for a two-wheeled electric vehicle, comprising the following steps:

[0006] In a first aspect, an embodiment of the present application provides a method for adjusting wireless charging power for a two-wheeled electric vehicle, the method comprising the following steps:

[0007] The initial SOC value of the battery before the two-wheeled electric vehicle starts charging is obtained by the open circuit voltage method;

[0008] Obtain the input power of the transmitting module and the output power of the receiving module of the wireless charging system at each moment, and collect the voltage, current and temperature of the battery at each moment;

[0009] Based on the temperature changes at each moment, the temperature rise coefficient at each moment is calculated; the estimated SOC value of the battery at each moment is determined by integrating the current changes at different moments, combining the initial SOC value and the temperature rise coefficient;

[0010] The charging efficiency of the battery at each moment is obtained by the difference between the estimated SOC value of the battery at each moment and its adjacent moments, as well as the difference between the input power and the output power at each moment;

[0011] Based on the estimated SOC value, determine the charging stage at each moment and switch the corresponding charging mode, wherein the charging stage includes a constant current charging stage and a constant voltage charging stage;

[0012] The current deviation at each moment in the constant current charging stage and the voltage deviation at each moment in the constant voltage charging stage are analyzed respectively, and the wireless charging power in the constant current charging stage and the constant voltage charging stage are evaluated. The temperature rise coefficient and the charging efficiency are combined to obtain the adjusted charging power at each moment in the constant current charging stage and the constant voltage charging stage; the charging power is adjusted in real time during the wireless charging process.

[0013] Preferably, the calculating of the temperature rise coefficient at each moment includes:

[0014] Calculate the difference between the temperature at each moment and the initial temperature of the battery before charging begins, and record it as the relative temperature difference;

[0015] The ratio of the relative temperature difference to the initial temperature is taken as the temperature rise coefficient at each moment.

[0016] Preferably, the calculation formula of the estimated SOC value of the battery at each moment is: ,in, is the estimated SOC value at time t, is the estimated SOC value at the qth moment, is the rated capacity of the battery, is the fitting function of the current at all times between the qth moment and the tth moment; is the temperature rise coefficient at the qth moment, is the time interval between the start of charging and the qth moment in the wireless charging process, is the number of all moments before moment t, where, when q=0, is the initial SOC value.

[0017] Preferably, obtaining the charging efficiency of the battery at each moment includes:

[0018] The difference between the input power of the transmitting module and the output power of the receiving module at each moment is taken as the power consumption of the electromagnetic conversion process at each moment;

[0019] The product of the time interval between two adjacent moments and the power consumption is recorded as the energy consumption;

[0020] Calculate the difference in the estimated SOC value of the battery between two adjacent moments, record it as a relative difference, and multiply the relative difference by the rated capacity, record it as a relative growth energy;

[0021] The charging efficiency is the ratio of the relative increase energy to the consumed energy.

[0022] Preferably, the determining the charging stage at each moment includes:

[0023] If the estimated SOC value at each moment is less than , at this time it is in the constant current charging stage, and the constant current charging mode is used for charging;

[0024] If the estimated SOC value at each moment is greater than If the voltage is less than b%, and the voltage is less than the preset constant voltage, it is in the constant current charging stage and the constant current charging mode is used for charging;

[0025] If the estimated SOC value at each moment is greater than When the voltage reaches the preset constant voltage, it is in the constant voltage charging stage and is switched to the constant voltage charging mode for charging; wherein a% and b% are preset values.

[0026] Preferably, evaluating the wireless charging power in the constant current charging stage includes:

[0027] Calculate the difference between the current at each moment in the constant current charging stage and the preset constant current, and record it as the relative current difference;

[0028] The ratio between the relative current difference and the preset constant current is used as the current deviation at each moment in the constant current charging stage;

[0029] If the current deviation is greater than a preset first threshold, the wireless charging power needs to be adjusted; otherwise, the wireless charging power does not need to be adjusted.

[0030] Preferably, obtaining the adjusted charging power at each moment in the constant current charging stage includes:

[0031] In the constant current charging stage, if the current at each moment is greater than the preset constant current, the current deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1;

[0032] The charging power adjusted at time p during the constant current charging phase The calculation formula is: ,in, is the unadjusted charging power at time p, is the current deviation factor at the pth moment, is the current deviation at the pth moment, is the charging efficiency at the pth moment, is the temperature rise coefficient at the pth moment, is the preset adjustment amount.

[0033] Preferably, evaluating the wireless charging power during the constant voltage charging stage includes:

[0034] Calculating the difference between the voltage at each moment in the constant voltage charging stage and the preset constant voltage, and recording it as a relative voltage difference;

[0035] The ratio between the relative voltage difference and the preset constant voltage is used as the voltage deviation at each moment in the constant voltage charging stage;

[0036] If the voltage deviation is greater than the preset second threshold, the wireless charging power needs to be adjusted; otherwise, the wireless charging power does not need to be adjusted.

[0037] Preferably, obtaining the adjusted charging power at each moment in the constant voltage charging stage includes:

[0038] In the constant voltage charging stage, if the voltage at each moment is greater than the preset constant voltage, the voltage deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1;

[0039] The calculation formula for the adjusted charging power at each moment during the constant voltage charging stage is: ,in, The first The charging power after adjustment at all times, For the The charging power is not adjusted at all times. For the The voltage deviation factor at time For the The voltage deviation at the time, For the Charging efficiency at all times, For the The temperature rise coefficient at time, is the preset adjustment amount.

[0040] In a second aspect, an embodiment of the present application also provides a wireless charging power regulation system for a two-wheeled electric vehicle, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of a wireless charging power regulation method for a two-wheeled electric vehicle as described in any one of the above items are implemented.

[0041] This application has at least the following beneficial effects:

[0042] The present application calculates the temperature rise coefficient at each moment by analyzing the difference between the temperature of the battery at different moments in the wireless charging process and the initial temperature before charging begins, and estimates the SOC at each moment in the charging process according to the change in the temperature rise coefficient. The beneficial effect of this application is that the real-time charging state of the battery can be clearly understood, so that the charging demand of the battery can be grasped according to the charge state of the battery in the future, thereby dynamically adjusting the charging power; secondly, the charging stage at different moments can be judged by the estimated SOC value of the battery at each moment, and then the charging mode of the corresponding stage can be switched. The beneficial effect of this application is that different charging modes are adopted in different charging stages, so as to ensure the safety and efficiency of the charging process and avoid the occurrence of overcharging or undercharging; secondly, the power difference between the transmitting module and the receiving module in the wireless charging system, as well as the change in the estimated SOC value at adjacent moments, can be used to determine the charging stage at different moments. The charging efficiency is calculated based on the situation. The beneficial effect is that the power consumed in the electromagnetic conversion process between the transmitting module and the receiving module and the increase in the charge of the battery at this time are taken into account to reflect the charging effect of the battery at this time. Further, for different charging stages, the deviation of voltage or current at different times is analyzed, and the voltage deviation and current deviation are calculated to evaluate whether the wireless charging power needs to be adjusted at this moment in the corresponding stage. Then, the wireless charging power at each moment in different stages is adjusted in combination with the temperature rise coefficient and the charging efficiency to obtain the adjusted charging power at each moment. The beneficial effect is that the charging power at different moments in different stages can be dynamically adjusted to meet the charging needs of the battery at different times, so as to ensure the safety of battery charging while improving the efficiency of wireless charging, while reducing energy loss and avoiding overcharging of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The following is a further detailed description of a wireless charging power regulation method for a two-wheeled electric vehicle of the present application in conjunction with the accompanying drawings.

[0044] Figure 1 A flowchart of a method for adjusting wireless charging power for a two-wheeled electric vehicle provided in an embodiment of the present application;

[0045] Figure 2 A schematic diagram of the overall structure of a two-wheeled vehicle wireless charging system provided in an embodiment of the present application;

[0046] Figure 3 A flowchart of the steps of a method for obtaining the charging efficiency of a battery at each moment provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of this application more clear, the following is a further detailed description of a wireless charging power adjustment method and system for a two-wheeled electric vehicle proposed in this application in combination with the accompanying drawings and implementation examples. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0048] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0049] See also Figure 1 , which shows a flowchart of a method for adjusting wireless charging power for a two-wheeled electric vehicle provided by an embodiment of the present application, the method comprising the following steps:

[0050] Step 1: Obtain the initial SOC value of the battery before the two-wheeled electric vehicle starts charging by using the open circuit voltage method; obtain the input power of the transmitting module and the output power of the receiving module of the wireless charging system at each moment, and collect the voltage, current and temperature of the battery at each moment.

[0051] The overall structural diagram of the two-wheeled vehicle wireless charging system is as follows Figure 2 As shown, it includes two parts, a power supply host and a receiving device. The power supply host is connected to a transformer through a mains access terminal to connect to the power supply in the urban area. The wireless communication module controls the transformer through a microprocessor to convert it into electric energy suitable for wireless transmission. Secondly, after the electric energy is converted into electromagnetic waves through the transmitting module, the electric energy is transmitted to the receiving device through wireless transmission. In the receiving device, the receiving module receives the electric energy, and converts the alternating current into direct current through the DC module to charge the battery of the two-wheeled electric vehicle. The GPS communication module monitors the location information of the wireless charging device in order to clarify the charging status of the charging device.

[0052] When wirelessly charging a two-wheeled electric vehicle, the impedance and charging requirements of the battery will change with factors such as the battery's state of charge (SOC), temperature, and degree of aging. If a fixed power is used to charge the battery, the power transmission efficiency will be low.

[0053] During the charging process, the change of the SOC of the battery will directly affect the charging strategy. When the SOC of the battery is low, that is, the battery power is low at 0%~20%, the constant current charging mode is usually adopted at this stage to quickly improve the SOC. In this embodiment, the initial power of the wireless charging at this stage is set to 2KW, and the constant current charging current is 0.2C, where C is the rated capacity of the battery of the two-wheeled electric vehicle. In this embodiment, the rated capacity C is 20Ah; when the SOC of the battery rises to 20%-80%, the battery enters the high-efficiency charging range, and the constant current charging mode is first used for charging. At this time, the constant current charging current is 0.5C, and the voltage It gradually rises. When the voltage reaches 4.2V, the constant current charging ends and switches to the constant voltage charging mode for charging. In this embodiment, the initial power of wireless charging is set to 5KW at this stage, and the initial voltage of constant voltage charging is 4.2V. When the SOC of the battery is high, that is, when the battery power reaches 80%-100%, the battery is close to a full charge state, and the charging speed slows down. At this stage, the constant voltage charging mode switches to the trickle charging mode. At this stage, the trickle charging current is 0.01C to prevent overcharging and overheating. Therefore, there are three stages in the charging process of the two-wheeled electric vehicle, namely, the constant current charging stage, the constant voltage charging stage, and the trickle charging stage.

[0054] Based on the above analysis, it is necessary to judge the charging stage of the battery inside the two-wheeled electric vehicle. Therefore, it is necessary to clarify the SOC value of the battery at different times and measure the initial SOC value of the battery before charging by the open circuit voltage method. Specifically:

[0055] First, before charging the two-wheeled electric vehicle, the battery is left to stand for a period of time, and the open circuit voltage (OCV) of the battery is measured by the open circuit voltage method (OCV). The SOC value of the battery before charging is determined through the OCV-SOC curve, which is recorded as the initial SOC value.

[0056] It should be noted that the open circuit voltage method is a well-known technology and will not be described in detail here.

[0057] Secondly, during the battery charging process of the two-wheeled electric vehicle, the voltage, current and temperature of the battery are collected in real time.

[0058] During the wireless charging process, the input power of the transmitting module and the output power of the receiving module of the wireless charging system at each time are obtained;

[0059] At this point, the voltage, current, temperature of the battery, the initial SOC value of the battery, and the input power of the transmitting module of the wireless charging system at each moment and the output power of the receiving module at each moment are obtained in real time.

[0060] Step 2, based on the temperature change at each moment, calculate the temperature rise coefficient at each moment; determine the estimated SOC value of the battery at each moment by integrating the current change at different moments, combining the initial SOC value and the temperature rise coefficient.

[0061] Furthermore, the battery of the two-wheeled electric vehicle is wirelessly charged. As the charging progresses, the SOC value of the battery continues to rise. Since the SOC value of the battery is needed to determine the charging stage of the battery charging process, the charging power is adjusted in real time according to the different stages of the charging process. When the open circuit voltage method is used to measure the SOC value of the battery, the battery needs to be left stationary. At this time, it is in a wireless charging state and the open circuit voltage method cannot be used. Therefore, the SOC value of the battery at different times during the wireless charging process is estimated by the current integration method.

[0062] Secondly, the accuracy of the SOC value estimation will directly affect the subsequent control accuracy. When the current integration method is used to calculate the SOC value, its accuracy will be affected by the current collection at different times. During the wireless charging process, as the charging progresses, the impedance of the battery decreases and the temperature rises, the accuracy of the current obtained in real time will decrease to a certain extent, resulting in a decrease in the accuracy of the estimated SOC value. Therefore, in order to make the estimation of the SOC value more accurate, it is necessary to consider the influence of temperature.

[0063] It should be noted that the current integration method is a well-known technology and will not be described in detail here. Among them, the traditional method calculates the SOC value at each moment through the current integration method, and the calculation process is: ,in, is the SOC value at time t, is the initial SOC value, is the rated capacity of the battery, It is the fitting function of the battery current at all times between the start time and the tth time.

[0064] When the traditional current integration method estimates the SOC value, the impact of battery temperature changes on the charging process is not considered. Therefore, the temperature rise degree is analyzed by the temperature change of the battery at different times, and the temperature rise coefficient is calculated, which is specifically:

[0065] Calculate the difference between the temperature at each moment and the initial temperature of the battery before charging begins, and record it as the relative temperature difference;

[0066] In this embodiment, the absolute value of the difference between the temperature at each moment and the initial temperature of the battery before charging is started is calculated and recorded as the relative temperature difference.

[0067] The ratio of the relative temperature difference to the initial temperature is taken as the temperature rise coefficient at each moment;

[0068] In this embodiment, the calculation process of the temperature rise coefficient at each moment is:

[0069]

[0070] in, is the temperature rise coefficient at time t, is the temperature at time t, is the initial temperature of the battery before charging.

[0071] It should be noted that, the greater the temperature rise, the greater the impact of temperature on the wireless charging process of the battery.

[0072] The calculation formula for the estimated SOC value of the battery at each moment is:

[0073]

[0074] in, is the estimated SOC value at time t, is the estimated SOC value at the qth moment, is the rated capacity of the battery, is the fitting function of the current at all times between the qth moment and the tth moment; is the temperature rise coefficient at the qth moment, is the time interval between the start of charging and the qth moment in the wireless charging process, is the number of all moments before the tth moment.

[0075] In this embodiment, the least square method is used to fit the current at all times between the qth time and the tth time, wherein the least square method is a well-known technology and will not be described in detail here.

[0076] It should be noted that when q=0, is the initial SOC value before the battery starts charging, from which the estimated SOC value at each moment can be obtained.

[0077] At this point, the estimated SOC value of the battery at each moment is obtained.

[0078] Step 3, obtaining the charging efficiency of the battery at each moment through the difference between the estimated SOC value of the battery at each moment and its adjacent moments, as well as the difference between the input power and the output power at each moment; based on the estimated SOC value, judging the charging stage at each moment, switching the corresponding charging mode, the charging stage includes a constant current charging stage, a constant voltage charging stage, and a trickle charging stage.

[0079] Furthermore, by analyzing the change of the estimated SOC value of the battery at adjacent moments, the charging efficiency of the battery at each moment is calculated. The step flow chart of the method for obtaining the charging efficiency of the battery at each moment provided in the embodiment of the present application is as follows: Figure 3 As shown, specifically including:

[0080] The power consumption of the electromagnetic conversion process at each moment is calculated by taking the difference between the input power of the transmitting module and the output power of the receiving module at each moment;

[0081] In this embodiment, the power consumption of the electromagnetic conversion process at each moment is calculated by taking the absolute value of the difference between the input power of the transmitting module and the output power of the receiving module at each moment.

[0082] Calculate the difference between the estimated SOC value of the battery at each moment and the estimated SOC value at the previous moment, and record it as the relative difference;

[0083] In this embodiment, the absolute value of the difference between the estimated SOC value of the battery at each moment and the estimated SOC value at the previous moment is calculated and recorded as the relative difference.

[0084] The product of the relative difference and the rated capacity is recorded as the relative growth energy;

[0085] The product of the time interval between two adjacent moments and the power consumption is recorded as the energy consumption;

[0086] The ratio of the relative increase energy to the consumed energy is used as the charging efficiency of the battery at each moment;

[0087] It should be noted that the energy consumption represents the wireless charging process, which is the energy consumed when the electrical energy at each moment is converted into electromagnetic waves for transmission through the transmitting module. The relative increase in energy represents the energy increased by charging the battery at two adjacent moments. The greater the charging efficiency obtained, the better the charging effect will be when the charging power at this time is used to charge the two-wheeled electric vehicle.

[0088] Secondly, through the estimated SOC value at each moment, we can determine the charging stage of the battery during wireless charging and formulate different charging strategies, specifically:

[0089] If the estimated SOC value at each moment is less than , at this time it is in the constant current charging stage, and the constant current charging mode is adopted;

[0090] If the estimated SOC value at each moment is greater than If the value is less than b%, and the voltage is less than the preset constant voltage, then it is in the constant current charging stage and the constant current charging mode is adopted;

[0091] If the estimated SOC value at each moment is greater than Less than b%, and the voltage reaches the preset constant voltage, it is in the constant voltage charging stage, and switches to the constant voltage charging mode;

[0092] If the estimated SOC value at each moment is greater than b%, it is in the trickle charging stage and switches to the trickle charging mode; a% and b% are preset values;

[0093] In this embodiment, a% is set to 20% and b% is set to 80%. For other implementations, implementers can set them according to actual conditions.

[0094] In this embodiment, in the constant current charging stage, the constant current charging mode is: during the wireless charging process, the charging power is 2KW, the constant current charging current is 0.2C, that is, the preset constant current is 4A, and the battery is charged; in the constant voltage charging stage, the constant voltage charging mode is: during the wireless charging process, the charging power is set to 5KW, the constant voltage charging voltage is 4.2V, that is, the preset constant voltage is 4.2V, and the battery is charged; in the trickle charging stage, the battery is close to full charge at this stage. In order to avoid overcharging or energy being wasted, the trickle charging mode is: the voltage remains constant, the current continues to decrease, and the charging power is reduced to 10% of the rated power to charge the battery.

[0095] At this point, the charging efficiency at each moment and the charging stage at each moment are obtained.

[0096] Step 4, respectively analyzing the deviation of the current at each moment in the constant current charging stage and the deviation of the voltage at each moment in the constant voltage charging stage, evaluating the wireless charging power in the constant current charging stage and the constant voltage charging stage, respectively combining the temperature rise coefficient and the charging efficiency, to obtain the adjusted charging power at each moment in the constant current charging stage and the constant voltage charging stage; and adjusting the charging power in real time during the wireless charging process.

[0097] During the charging process of a two-wheeled electric vehicle, the battery charging current cannot remain constant due to changes in battery impedance and temperature. Therefore, the power of wireless charging needs to be adjusted to keep the battery charging amount stable, thereby improving charging efficiency, reducing energy loss and protecting the battery.

[0098] Based on the above analysis, for different charging stages, the changes in the battery's current or voltage at each moment are analyzed to evaluate whether the battery's charging power needs to be adjusted at this time. In the constant current charging stage, the greater the deviation between the current at different moments and the preset constant current, the greater the deviation between the battery's charging state and the expected charging strategy, and the more the wireless charging power should be adjusted. If the wireless charging power is not adjusted, the charging efficiency will be reduced, the energy loss will increase, and it may even cause damage to the battery. Therefore, by adjusting the wireless charging power in real time, it can ensure that the battery charging amount remains stable, improve the charging efficiency, reduce energy loss, and protect the battery while avoiding overcharging and overheating.

[0099] Therefore, in the constant current charging stage, the deviation between the current at each moment and the preset constant current is analyzed, and the current deviation is calculated, specifically:

[0100] Calculating the difference between the current at each moment in the constant current charging stage and the preset constant current, and recording it as a relative current difference;

[0101] In this embodiment, the absolute value of the difference between the current at each moment in the constant current charging stage and the preset constant current is calculated and recorded as the relative current difference.

[0102] The ratio between the relative current difference and the preset constant current is used as the current deviation at each moment in the constant current charging stage;

[0103] In this embodiment, since the rated capacity of the battery in the two-wheeled electric vehicle is 20Ah, the constant current is preset to 4A. As for other implementation methods, the implementer can set it according to the actual situation.

[0104] In this embodiment, the calculation process of the current deviation at each moment in the constant current charging stage is:

[0105]

[0106] in, For the The current deviation at a moment, For the The current at that moment, is the preset constant current.

[0107] In the constant current charging stage, if the current at each moment is greater than the preset constant current, the current deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1;

[0108] If the current deviation is greater than the preset first threshold, the wireless charging power needs to be adjusted, otherwise, the wireless charging power does not need to be adjusted;

[0109] In this embodiment, the preset first threshold value is 0.1. As for other implementation modes, the implementer can set it according to the actual situation.

[0110] It should be noted that, the greater the current deviation is, the lower the current constancy is when the battery is wirelessly charged, and the more the wireless charging power should be adjusted.

[0111] Further, in the constant current charging stage, based on the current deviation, the current deviation factor and the temperature rise coefficient, the charging power at each moment is adjusted to obtain the adjusted charging power, specifically:

[0112]

[0113] in, is the charging power adjusted at time p during the constant current charging stage, is the unadjusted charging power at time p, is the current deviation factor at the pth moment, is the current deviation at the pth moment, is the charging efficiency at the pth moment, is the temperature rise coefficient at the pth moment, is the preset adjustment amount.

[0114] In this embodiment, the preset adjustment amount F is set to 1KW. As for other implementations, the implementer can set it according to the actual situation.

[0115] It should be noted that the greater the current deviation, the greater the deviation between the battery's charging state and the expected charging strategy, and the greater the adjustment of the battery's charging power. Secondly, the greater the charging efficiency, the better the charging effect of the two-wheeled electric vehicle, and the smaller the adjustment of the charging power should be; the greater the temperature rise coefficient, the higher the temperature rise, the more likely it is to cause safety problems, so the smaller the adjustment of the charging power should be; the current deviation factor is to control the adjustment direction of the charging power, and whether the charging power should be increased or decreased at this time.

[0116] Secondly, when the battery voltage reaches the preset constant voltage of 4.2V during charging, the charging process is in the constant voltage charging stage and switches to the constant voltage charging mode. Therefore, in the constant voltage charging stage, the deviation between the voltage at each moment and the preset constant voltage is analyzed and the voltage deviation is calculated, which is specifically:

[0117] Calculating the difference between the voltage at each moment in the constant voltage charging stage and the preset constant voltage, and recording it as a relative voltage difference;

[0118] In this embodiment, the absolute value of the difference between the voltage at each moment in the constant voltage charging stage and the preset constant voltage is calculated and recorded as the relative voltage difference, wherein the preset constant voltage is 4.2V. As other implementation methods, the implementer can set it according to the actual situation.

[0119] The ratio between the relative voltage difference and the preset constant voltage is used as the voltage deviation at each moment in the constant voltage charging stage;

[0120] In this embodiment, the calculation formula for the voltage deviation at each moment in the constant voltage charging stage is:

[0121]

[0122] in, For the The voltage deviation at the time, For the The voltage at the moment, is the preset constant voltage.

[0123] In the constant voltage charging stage, if the voltage at each moment is greater than the preset constant voltage, the voltage deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1;

[0124] If the voltage deviation is greater than the preset second threshold, the wireless charging power needs to be adjusted, otherwise, the wireless charging power does not need to be adjusted;

[0125] In this embodiment, the preset second threshold value is 0.1. As other implementation modes, the implementer can set it according to the actual situation.

[0126] It should be noted that the greater the voltage deviation is, the lower the voltage constancy is when the battery is wirelessly charged, and the more the wireless charging power should be adjusted.

[0127] Furthermore, in the constant voltage charging stage, the charging power at each moment is adjusted based on the voltage deviation, the voltage deviation factor and the temperature rise coefficient to obtain the adjusted charging power, specifically:

[0128]

[0129] in, The first The charging power after adjustment at all times, For the The charging power is not adjusted at all times. For the The voltage deviation factor at time For the The voltage deviation at the time, For the Charging efficiency at all times, For the The temperature rise coefficient at time, is the preset adjustment amount.

[0130] In this embodiment, the preset adjustment amount F is set to 1KW. As for other implementations, the implementer can set it according to the actual situation.

[0131] It should be noted that the voltage deviation indicates the degree of deviation between the voltage during the charging process and the preset constant voltage. The greater the voltage deviation, the greater the adjustment of the battery charging power. Secondly, the greater the charging efficiency, the better the charging effect of the two-wheeled electric vehicle, and the smaller the adjustment of the charging power should be; the greater the temperature rise coefficient, the higher the temperature rise, the more likely it is to cause safety problems, so the smaller the adjustment of the charging power should be; the voltage deviation factor is to control the adjustment direction of the charging power, and whether the charging power should be increased or decreased at this time.

[0132] Furthermore, when the estimated SOC value of the battery reaches 80%, it switches from constant voltage charging mode to trickle charging mode. At this time, it is in the trickle charging stage. In this stage, the voltage remains constant, the current continues to decrease, and the charging power is reduced to 10% of the rated power to charge the battery.

[0133] Therefore, the wireless charging power is adjusted through different charging stages to wirelessly charge the battery of the two-wheeled electric vehicle, so as to ensure the safety of battery charging while improving the efficiency of wireless charging, reducing energy loss and avoiding overcharging of the battery.

[0134] Based on the same inventive concept as the above method, an embodiment of the present application also provides a wireless charging power regulation system for a two-wheeled electric vehicle, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of any one of the above-mentioned methods for wireless charging power regulation for a two-wheeled electric vehicle are implemented.

[0135] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0136] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0137] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the present application. It should be pointed out that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application without departing from the content of the technical solution of the present application, shall fall within the protection scope of the technical solution of the present application.

Claims

1. A wireless charging power adjustment method for a two-wheeled electric vehicle, characterized in that: The method comprises the following steps: The initial SOC value of the battery before the two-wheeled electric vehicle starts charging is obtained by the open circuit voltage method; Obtain the input power of the transmitting module and the output power of the receiving module of the wireless charging system at each moment, and collect the voltage, current and temperature of the battery at each moment; Based on the temperature changes at each moment, the temperature rise coefficient at each moment is calculated; the estimated SOC value of the battery at each moment is determined by integrating the current changes at different moments, combining the initial SOC value and the temperature rise coefficient; The charging efficiency of the battery at each moment is obtained by the difference between the estimated SOC value of the battery at each moment and its adjacent moments, as well as the difference between the input power and the output power at each moment; Based on the estimated SOC value, determine the charging stage at each moment and switch the corresponding charging mode, wherein the charging stage includes a constant current charging stage and a constant voltage charging stage; The current deviation at each moment in the constant current charging stage and the voltage deviation at each moment in the constant voltage charging stage are analyzed respectively, and the wireless charging power in the constant current charging stage and the constant voltage charging stage are evaluated. The temperature rise coefficient and the charging efficiency are combined to obtain the adjusted charging power at each moment in the constant current charging stage and the constant voltage charging stage; the charging power is adjusted in real time during the wireless charging process.

2. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 1, characterized in that: The calculating of the temperature rise coefficient at each moment includes: Calculate the difference between the temperature at each moment and the initial temperature of the battery before charging begins, and record it as the relative temperature difference; The ratio of the relative temperature difference to the initial temperature is taken as the temperature rise coefficient at each moment.

3. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 1, characterized in that: The calculation formula of the estimated SOC value of the battery at each moment is: ,in, is the estimated SOC value at time t, is the estimated SOC value at the qth moment, is the rated capacity of the battery, is the fitting function of the current at all times between the qth moment and the tth moment; is the temperature rise coefficient at the qth moment, is the time interval between the start of charging and the qth moment in the wireless charging process, is the number of all moments before moment t, where, when q=0, is the initial SOC value.

4. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 1, characterized in that: The obtaining of the charging efficiency of the battery at each moment includes: The difference between the input power of the transmitting module and the output power of the receiving module at each moment is taken as the power consumption of the electromagnetic conversion process at each moment; The product of the time interval between two adjacent moments and the power consumption is recorded as the energy consumption; Calculate the difference in the estimated SOC value of the battery between two adjacent moments, record it as a relative difference, and multiply the relative difference by the rated capacity, record it as a relative growth energy; The charging efficiency is the ratio of the relative increase energy to the consumed energy.

5. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 1, characterized in that: The step of determining the charging stage at each moment includes: If the estimated SOC value at each moment is less than , at this time it is in the constant current charging stage, and the constant current charging mode is used for charging; If the estimated SOC value at each moment is greater than If the voltage is less than b%, and the voltage is less than the preset constant voltage, it is in the constant current charging stage and the constant current charging mode is used for charging; If the estimated SOC value at each moment is greater than When the voltage reaches the preset constant voltage, it is in the constant voltage charging stage and is switched to the constant voltage charging mode for charging; wherein a% and b% are preset values.

6. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 1, characterized in that: Evaluate the wireless charging power during the constant current charging stage, including: Calculate the difference between the current at each moment in the constant current charging stage and the preset constant current, and record it as the relative current difference; The ratio between the relative current difference and the preset constant current is used as the current deviation at each moment in the constant current charging stage; If the current deviation is greater than a preset first threshold, the wireless charging power needs to be adjusted; otherwise, the wireless charging power does not need to be adjusted.

7. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 6, characterized in that: The adjusted charging power at each moment in the constant current charging stage is obtained, including: In the constant current charging stage, if the current at each moment is greater than the preset constant current, the current deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1; The charging power adjusted at time p during the constant current charging phase The calculation formula is: ,in, is the unadjusted charging power at time p, is the current deviation factor at the pth moment, is the current deviation at the pth moment, is the charging efficiency at the pth moment, is the temperature rise coefficient at the pth moment, is the preset adjustment amount.

8. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 5, characterized in that: Evaluate the wireless charging power during the constant voltage charging stage, including: Calculating the difference between the voltage at each moment in the constant voltage charging stage and the preset constant voltage, and recording it as a relative voltage difference; The ratio between the relative voltage difference and the preset constant voltage is used as the voltage deviation at each moment in the constant voltage charging stage; If the voltage deviation is greater than the preset second threshold, the wireless charging power needs to be adjusted; otherwise, the wireless charging power does not need to be adjusted.

9. A wireless charging power adjustment method for a two-wheeled electric vehicle as claimed in claim 8, characterized in that: The adjusted charging power at each moment in the constant voltage charging stage is obtained, including: In the constant voltage charging stage, if the voltage at each moment is greater than the preset constant voltage, the voltage deviation factor at each moment is assigned a value of -1, otherwise, it is assigned a value of 1; The calculation formula for the adjusted charging power at each moment during the constant voltage charging stage is: ,in, The first The charging power after adjustment at all times, For the The charging power is not adjusted at all times. For the The voltage deviation factor at time For the The voltage deviation at the time, For the Charging efficiency at all times, For the The temperature rise coefficient at time, is the preset adjustment amount.

10. A wireless charging power regulation system for a two-wheeled electric vehicle, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of a wireless charging power adjustment method for a two-wheeled electric vehicle as described in any one of claims 1-9 are implemented.

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