A wireless power supply transmitter control method and system

Abstract

The present invention relates to the field of wireless power supply technology, and in particular to a wireless power supply transmitter control method and system. The transmitter current is controlled by adaptive adjustment of a PID controller. First, the Ziegler-Nichols method is used to set the initial PID parameter value; the actual transmission current and the actual output power are obtained by real-time monitoring of the output of the system by a sensor, and the error and the rate of change between the actual transmission current and the actual output power and the reference value are calculated; the PID parameters are adjusted according to an improved adaptive fuzzy logic control algorithm; and finally, the adjusted PID parameters are used to generate a control signal to adjust the transmission current. The present invention dynamically adjusts the PID parameters through an adaptive fuzzy logic control algorithm, which can effectively cope with system parameter changes and external interference, and improve the stability and robustness of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power supply, and in particular to a wireless power supply transmitter control method and system. Background Art

[0002] Wireless power supply technology transmits electrical energy in a contactless manner and is widely used in electric vehicle charging, medical equipment power supply, consumer electronics charging and other fields. Traditional wireless power supply systems usually use a fixed PID controller to control the current at the transmitter to ensure the stability and efficiency of the system. However, fixed PID parameters are difficult to adapt to system dynamic changes and external interference, resulting in a decrease in control performance.

[0003] Deficiencies of existing technology:

[0004] 1. Limitations of fixed PID parameters

[0005] Static parameters: The parameters of traditional PID controllers are usually fixed, which makes it difficult to adapt to system dynamic changes and external interference. When system parameters change, the PID controller with fixed parameters may lead to a decrease in control performance or even cause system instability.

[0006] Manual adjustment: Fixed PID parameters need to be adjusted manually, which is time-consuming and labor-intensive. The adjustment effect depends on the engineer's experience, making it difficult to achieve optimal control performance.

[0007] 2. Lack of adaptive ability

[0008] Static control: Most existing wireless power supply systems use static control methods, which lack adaptive capabilities. When the system is subject to external interference or internal parameter changes, the static control method is difficult to adjust in time, resulting in a decrease in control performance.

[0009] Poor robustness: When facing a complex and changing environment, the PID controller with fixed parameters has poor robustness and is easily affected by external interference, resulting in unstable system performance.

[0010] 3. Disadvantages of fuzzy logic control

[0011] Simple fuzzy rules: Existing fuzzy logic control methods often use simple fuzzy rules, which are difficult to handle complex nonlinear problems. In practical applications, simple fuzzy rules may not accurately describe the dynamic behavior of the system, resulting in poor control effects. Summary of the invention

[0012] The present invention provides a wireless power supply transmitter control method and system, which realizes high-precision, fast-response and high-stability control of the transmission current by dynamically adjusting PID parameters, thus providing a strong guarantee for the efficient and safe operation of the wireless power supply system.

[0013] In order to achieve the purpose of the present invention, the technical solution adopted is: a wireless power supply transmitter control method, which controls the transmitter current through adaptive adjustment of the PID controller, specifically including:

[0014] S1. Use the Ziegler-Nichols method to set the initial PID parameter values;

[0015] S2. Obtain the actual transmission current and the actual output power by monitoring the output of the system in real time through the sensor, and calculate the error between the actual transmission current and the actual output power and the reference value and the rate of change thereof;

[0016] S3, adjusting PID parameters according to the improved adaptive fuzzy logic control algorithm;

[0017] S4. Generate a control signal using the adjusted PID parameters to adjust the emission current.

[0018] As an optimization solution of the present invention, in step S2, the error between the actual emission current and the reference value is the emission current error, and the emission current error e I for:

[0019] e I =I ref –I true

[0020] The error change rate of the emission current is

[0021]

[0022] The error between the actual output power and the reference value is the output power error. P for:

[0023] e P =P ref –P true

[0024] The output power error change rate is

[0025]

[0026] Where: I ref is the reference value of the emission current, I true is the actual emission current, P ref is the reference value of output power, P true is the actual output power, t is the current time point, and Δt is the time interval.

[0027] As an optimization solution of the present invention, in step S3, specifically including:

[0028] S3-1. Define fuzzy variables, which include input variables and output variables;

[0029] S3-2. Define a membership function, which includes a membership function of an input variable and a membership function of an output variable;

[0030] S3-3, formulating fuzzy rules, including fuzzy rules for transmission current error and error change rate and fuzzy rules for output power error and error change rate;

[0031] S3-4, fuzzy reasoning, uses the Mamdani method to calculate the output of each rule, synthesizes the outputs of all rules, and obtains the final PID parameter adjustment amount.

[0032] As an optimization scheme of the present invention, in step S3-1, the input variables include the transmission current error, the transmission current error change rate, the output power error and the output power error change rate, and the output variable includes the proportional gain adjustment amount ΔK p , Integral gain adjustment ΔK i And the differential gain adjustment ΔK d .

[0033] As an optimization scheme of the present invention, the Mamdani method is used to calculate the output fuzzy set of each rule according to the fuzzy rules, the maximum product synthesis method is used to synthesize the output fuzzy sets of all rules to obtain the total fuzzy output set, and the improved defuzzification method is used to convert the fuzzy output set into a clear value, thereby obtaining the final PID parameter adjustment amount.

[0034] As an optimization solution of the present invention, the improved defuzzification method is the weighted centroid method, and the clarity value ΔK of the weighted centroid method is calculated. p for:

[0035]

[0036] Where: x i is the value of the output variable, μ i (x i ) is the output fuzzy set of the i-th rule in x i The degree of membership at i is the weight factor of the ith rule.

[0037] As an optimization solution of the present invention, the control signal is generated using the updated PID parameters:

[0038]

[0039] The generated control signal u(t) is used to adjust the output of the inverter and the modulation ratio M of the inverter to control the emission current, specifically:

[0040]

[0041] Among them: U max is the maximum output voltage of the inverter.

[0042] In order to achieve the purpose of the present invention, the technical scheme adopted is: a control system of a wireless power supply transmitter control method, characterized in that it includes a reference value setting module, an error calculation module, a fuzzy logic control module and a PID controller, the sensor real-time monitoring system transmits the monitored actual transmission current and actual output power to the error calculation module, the error calculation module calculates the error and its change rate between the actual transmission current and the actual output power and the reference value based on the reference value setting module, and transmits the result to the fuzzy logic control module, the fuzzy logic control module uses fuzzy rules and membership functions to perform fuzzy reasoning according to the error and its change rate, and generates the adjustment amount ΔK of the PID parameter. p , ΔK i , ΔK d The PID controller updates the PID parameters according to these adjustment quantities and generates a control signal u(t). The PID controller transmits the generated control signal u(t) to the inverter. The inverter adjusts the modulation ratio M according to the control signal u(t) to control the emission current.

[0043] The present invention has positive effects: 1) The present invention dynamically adjusts PID parameters through an adaptive fuzzy logic control algorithm, which can effectively cope with system parameter changes and external interference, and improve the stability and robustness of the system. In particular, when the system encounters uncertainties and nonlinear factors during operation, this method can better maintain the stability of the system;

[0044] 2) The present invention uses fuzzy logic control algorithm, which can accurately adjust PID parameters according to the transmission current error and output power error and their change rate, thereby achieving high-precision control of the transmission current. Accurate current control directly affects transmission efficiency and safety;

[0045] 3) The present invention monitors the system output in real time and calculates the error and its rate of change. This method can quickly detect changes in the system state and adjust the PID parameters in time to quickly restore the system to the desired state. This is particularly useful in dynamic environments and can significantly shorten the response time and improve the dynamic performance of the control system;

[0046] 4) The present invention uses an adaptive fuzzy logic control algorithm, and the system can automatically adjust the PID parameters, reducing the time and cost of manual debugging and improving the accuracy and reliability of parameter setting. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0048] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0049] like Figure 1 As shown, the present invention discloses a wireless power supply transmitter control method, which controls the transmitter current through adaptive adjustment of a PID controller, specifically including:

[0050] S1. Use the Ziegler-Nichols method to set the initial PID parameter values;

[0051] The Ziegler-Nichols method simplifies the PID controller into a pure proportional controller (i.e., the integral and differential gains are set to 0), and then gradually increases the proportional gain until the system enters a critical oscillation state. u and the oscillation period T u , the initial parameters of the PID controller can be calculated.

[0052] S2. Obtain the actual transmission current and the actual output power by monitoring the output of the system in real time through the sensor, and calculate the error between the actual transmission current and the actual output power and the reference value and the rate of change thereof;

[0053] In step S2, the error between the actual transmission current and the reference value is the transmission current error. I for:

[0054] e I =I ref –I true

[0055] The error rate of emission current is

[0056]

[0057] The error between the actual output power and the reference value is the output power error. P for:

[0058] e P =P ref –P true

[0059] The output power error rate is

[0060]

[0061] Where: I ref is the reference value of the emission current, I true is the actual emission current, P ref is the reference value of output power, P true is the actual output power, t is the current time point, and Δt is the time interval.

[0062] S3, adjusting PID parameters according to the improved adaptive fuzzy logic control algorithm;

[0063] In step S3, it specifically includes:

[0064] S3-1, define fuzzy variables, which include input variables and output variables; in step S3-1, the input variables include the transmission current error, the transmission current error change rate, the output power error and the output power error change rate, and the output variable includes the proportional gain adjustment ΔK p , Integral gain adjustment ΔK i And the differential gain adjustment ΔK d .

[0065] S3-2. Define a membership function, which includes a membership function of an input variable and a membership function of an output variable;

[0066] Membership functions of input variables:

[0067] Emission current error e I and the emission current error rate is

[0068] Negative Big (NB): Indicates a large negative error.

[0069] Negative Small (NS): Indicates a smaller negative error.

[0070] Zero (ZO): Indicates an error close to zero.

[0071] Positive Small (PS): Indicates a smaller positive error.

[0072] Positive Large (PB): Indicates a larger positive error.

[0073] Output power error P and output power error change rate

[0074] Negative Big (NB): Indicates a large negative error.

[0075] Negative Small (NS): Indicates a smaller negative error.

[0076] Zero (ZO): Indicates an error close to zero.

[0077] Positive Small (PS): Indicates a smaller positive error.

[0078] Positive Large (PB): Indicates a larger positive error.

[0079] Membership functions of output variables:

[0080] Adjustment amount of proportional gain ΔKp:

[0081] Negative Large (NB): Indicates a larger negative adjustment.

[0082] Negative Small (NS): Indicates a smaller negative adjustment.

[0083] Zero (ZO): Indicates an adjustment amount close to zero.

[0084] Positive Small (PS): Indicates a smaller positive adjustment.

[0085] Positive Big (PB): Indicates a larger positive adjustment amount.

[0086] The adjustment amount of the integral gain is the same as the adjustment amount of the differential gain.

[0087] S3-3, formulating fuzzy rules, including fuzzy rules for transmission current error and error change rate and fuzzy rules for output power error and error change rate;

[0088] The relevant rules are as follows:

[0089] 1)

[0090] 2)

[0091] 3)

[0092] 4)

[0093] 5)

[0094] The fuzzy rules for output power error and error change rate are similar to the above.

[0095] S3-4, fuzzy reasoning, uses the Mamdani method to calculate the output of each rule, synthesizes the outputs of all rules, and obtains the final PID parameter adjustment amount.

[0096] In step S3-4, it specifically includes: using the Mamdani method to calculate the output fuzzy set of each rule according to the fuzzy rules, using the maximum product synthesis method to synthesize the output fuzzy sets of all rules to obtain the total fuzzy output set, and using the improved defuzzification method to convert the fuzzy output set into a clear value, thereby obtaining the final PID parameter adjustment amount.

[0097] The improved defuzzification method is the weighted centroid method, and the clarity value ΔK of the weighted centroid method is calculated. p for:

[0098]

[0099] Where: x i is the value of the output variable, μ i (x i ) is the output fuzzy set of the i-th rule in x i The degree of membership at i is the weight factor of the ith rule.

[0100] S4. Generate a control signal using the adjusted PID parameters to adjust the emission current.

[0101] Generate control signals using the updated PID parameters:

[0102]

[0103] The generated control signal u(t) is used to adjust the output of the inverter and the modulation ratio M of the inverter to control the emission current, specifically:

[0104]

[0105] Among them: U max is the maximum output voltage of the inverter.

[0106] Further disclosed is a control system based on a wireless power supply transmitter control method, including a reference value setting module, an error calculation module, a fuzzy logic control module and a PID controller. The sensor real-time monitoring system transmits the monitored actual transmission current and actual output power to the error calculation module. The error calculation module calculates the error and its change rate between the actual transmission current and the actual output power and the reference value based on the reference value setting module, and transmits the result to the fuzzy logic control module. The fuzzy logic control module uses fuzzy rules and membership functions to perform fuzzy reasoning based on the error and its change rate to generate an adjustment amount ΔK of the PID parameter. p , ΔK i , ΔK dThe PID controller updates the PID parameters according to these adjustment quantities and generates a control signal u(t). The PID controller transmits the generated control signal u(t) to the inverter. The inverter adjusts the modulation ratio M according to the control signal u(t) to control the emission current.

[0107] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wireless power supply transmitter control method, characterized in that: The transmitter current is controlled through adaptive adjustment of the PID controller, including: S1. Use the Ziegler-Nichols method to set the initial PID parameter values; S2. Obtain the actual transmission current and the actual output power by monitoring the output of the system in real time through the sensor, and calculate the error between the actual transmission current and the actual output power and the reference value and the rate of change thereof; S3, adjusting PID parameters according to the improved adaptive fuzzy logic control algorithm; S4. Generate a control signal using the adjusted PID parameters to adjust the emission current.

2. A wireless power supply transmitter control method according to claim 1, characterized in that: In step S2, the error between the actual transmission current and the reference value is the transmission current error. I for: yes I =I ref –I true The error rate of emission current is The error between the actual output power and the reference value is the output power error. P for: e P =P ref –P true The output power error rate is Where: I ref is the reference value of the emission current, I true is the actual emission current, P ref is the reference value of output power, P true is the actual output power, t is the current time point, and Δt is the time interval.

3. A wireless power supply transmitter control method according to claim 2, characterized in that: In step S3, it specifically includes: S3-1. Define fuzzy variables, which include input variables and output variables; S3-2. Define a membership function, which includes a membership function of an input variable and a membership function of an output variable; S3-3, formulating fuzzy rules, including fuzzy rules for transmission current error and error change rate and fuzzy rules for output power error and error change rate; S3-4, fuzzy reasoning, uses the Mamdani method to calculate the output of each rule, synthesizes the outputs of all rules, and obtains the final PID parameter adjustment amount.

4. A wireless power supply transmitter control method according to claim 3, characterized in that: In step S3-1, the input variables include the transmission current error, the transmission current error change rate, the output power error and the output power error change rate, and the output variable includes the proportional gain adjustment amount ΔK p , Integral gain adjustment ΔK i And the differential gain adjustment ΔK d .

5. The method according to claim 4, characterized in that: In step S3-4, it specifically includes: using the Mamdani method to calculate the output fuzzy set of each rule according to the fuzzy rules, using the maximum product synthesis method to synthesize the output fuzzy sets of all rules to obtain the total fuzzy output set, and using the improved defuzzification method to convert the fuzzy output set into a clear value, thereby obtaining the final PID parameter adjustment amount.

6. A wireless power supply transmitter control method according to claim 5, characterized in that: The improved defuzzification method is the weighted centroid method, and the clarity value ΔK of the weighted centroid method is calculated. p for: Where: x i is the value of the output variable, μ i (x i ) is the output fuzzy set of the i-th rule in x i The degree of membership at i is the weight factor of the ith rule.

7. A wireless power supply transmitter control method according to claim 6, characterized in that: Generate control signals using the updated PID parameters: The generated control signal u(t) is used to adjust the output of the inverter and the modulation ratio M of the inverter to control the emission current, specifically: Among them: U max is the maximum output voltage of the inverter.

8. A control system using the wireless power supply transmitter control method according to claim 1, characterized in that: The system includes a reference value setting module, an error calculation module, a fuzzy logic control module and a PID controller. The sensor real-time monitoring system transmits the monitored actual emission current and actual output power to the error calculation module. The error calculation module calculates the error and its change rate between the actual emission current and actual output power and the reference value based on the reference value setting module, and transmits the result to the fuzzy logic control module. The fuzzy logic control module uses fuzzy rules and membership functions to perform fuzzy reasoning based on the error and its change rate to generate the adjustment amount ΔK of the PID parameter. p , ΔK i , ΔK d The PID controller updates the PID parameters according to these adjustment quantities and generates a control signal u(t). The PID controller transmits the generated control signal u(t) to the inverter. The inverter adjusts the modulation ratio M according to the control signal u(t) to control the emission current.

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