Voltage stabilization control method for dynamic wireless charging system based on adaptive loop compensation

Abstract

The application discloses a kind of based on adaptive loop compensation dynamic wireless charging system's voltage stabilizing control method.The application is divided into two steps, first, according to the expected phase margin and crossing frequency, feedback controller meeting the frequency domain design parameter is designed;Second, according to the feedback controller designed above, using reference model adaptive control theory, the feedback controller parameters are adaptively iterated to obtain the feedback controller with better performance.The application introduces adaptive control algorithm, compared with the conventional lead-lag loop compensation feedback controller, not only can make electric vehicle when carrying out static wireless charging have satisfactory anti-interference performance, but also can suppress the wide-range voltage disturbance caused by electric vehicle movement in dynamic wireless charging process, more practical, wider application range.

Description

Technical Field

[0001] This invention relates to a dynamic wireless charging system for electric vehicles in the field of control technology, and particularly to a voltage regulation control method for a dynamic wireless charging system for electric vehicles based on adaptive loop compensation. Background Technology

[0002] With the rapid increase in energy consumption and the continuous deterioration of environmental problems, electric vehicles, as an economical, energy-saving, and environmentally friendly new energy vehicle, have gained widespread attention. However, due to the limitations of power battery technology and charging technology, the further promotion of electric vehicles must solve the bottleneck problem of short driving range. Dynamic wireless charging technology, as an emerging solution, can enable electric vehicles to charge while driving, thereby alleviating the problem of short driving range. The movement of the electric vehicle causes the relative positions between the transmitting and receiving coils to change continuously, which places higher demands on the control performance of the dynamic wireless charging system. How to overcome the large-scale voltage disturbances during the movement of the electric vehicle and achieve voltage regulation control of the dynamic wireless charging system has become one of the urgent problems to be solved in the dynamic wireless charging system of electric vehicles. The schematic diagram of the voltage regulation control of the Buck type DC-DC converter at the energy receiving end of the dynamic wireless charging system of electric vehicles is shown below. Figure 1 As shown.

[0003] Existing frequency-domain based dynamic wireless charging systems for electric vehicles cannot suppress large-scale voltage disturbances caused by vehicle movement. The fundamental reason is that voltage disturbances significantly reduce the bandwidth of the closed-loop control system, thus limiting its disturbance suppression capability. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the adverse effects of large-scale voltage fluctuations caused by the movement of electric vehicles on dynamic wireless charging systems. It provides a voltage regulation control method for dynamic wireless charging systems of electric vehicles based on adaptive loop compensation. This method combines frequency-domain designed lead-lag loop compensation with reference model adaptive control. A feedback controller is designed based on desired frequency-domain design parameters. The reference model adaptive control algorithm is used to adaptively iterate the controller parameters to obtain an adaptive feedback controller that minimizes the error performance index function, thus achieving voltage regulation control of the DC-DC converter at the energy receiver of the dynamic wireless charging system of the electric vehicle. This invention combines a frequency-domain designed loop compensation feedback controller with adaptive control to obtain an adaptive loop compensation feedback controller, ultimately improving the bandwidth and disturbance suppression capability of the closed-loop control system.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] Step 1: Establish the transfer function model of the DC-DC converter at the energy receiver end of the electric vehicle dynamic wireless charging system;

[0007] Step 2: Based on the transfer function model of the DC-DC converter, design performance constraints according to the desired frequency domain, and construct a feedback controller;

[0008] Step 3: Combine the reference model adaptive control algorithm with the feedback controller to establish a reference model;

[0009] Step 4: Establish the error performance index function between the output of the DC-DC converter and the output of the reference model, determine the adaptive law based on the error performance index function, and solve for the adaptive parameter value that minimizes the error performance index function according to the adaptive law.

[0010] Step 5: Based on the feedback controller and the adaptive parameter values, obtain the adaptive feedback controller. Use the adaptive feedback controller to control the DC-DC converter at the energy receiving end of the electric vehicle dynamic wireless charging system, thereby realizing the voltage regulation control of the electric vehicle dynamic wireless charging system.

[0011] In step 1, the transfer function model of the DC-DC converter The formula is as follows:

[0012]

[0013] Where s represents the complex variable in the transfer function model, L b and C b These are the output inductor and output capacitor of the DC-DC converter, respectively, V buck R is the steady-state input voltage of the DC-DC converter, and R is the load resistance.

[0014] In step 2, the feedback controller G c The formula for (s) is as follows:

[0015]

[0016] Where, ω z1 and ω z2 These represent the first and second zeros of the feedback controller, ω. p0 ω p1 and ω p2 These represent the zeros, poles, first pole, and second pole of the feedback controller, respectively.

[0017] The desired frequency domain design performance constraints are as follows:

[0018]

[0019] |L(jωco )|=1

[0020] ∠L(jω co )=-π+φ M

[0021] Where L(s) represents the open-loop transfer function, Represents the transfer function model of a DC-DC converter; φ M and ω co Represent the desired phase margin and crossover frequency, respectively; |L(jω) co )| and ∠L(jω co ) represent the open-loop transfer function L(s) at the crossover frequency ω. co The amplitude and phase at the specified point; j represents the imaginary unit.

[0022] In step 3, the formula for the reference model is as follows:

[0023]

[0024]

[0025] Among them, v m Represents the reference model H dr The output variable of (s), where r represents the reference model H dr L(s) represents the reference input of L(s), and L(s) represents the open-loop transfer function.

[0026] Step 4 specifically involves:

[0027] First, we establish an error performance index function for the output of the DC-DC converter compared to the output of the reference model. The formula is as follows:

[0028]

[0029] Where ε represents the output voltage v of the DC-DC converter. o Compared with the output variable v of the reference model m The error between;

[0030] Next, based on the error performance index function The adaptive law is constructed as follows:

[0031]

[0032] in, This indicates the adaptive value of the parameters of the feedback controller. The derivative of γ, where γ represents the adaptive gain coefficient, and e represents the difference between the reference input r of the reference model and the output voltage v of the DC-DC converter. o The error between;

[0033] Finally, the adaptive law is solved using the gradient descent method, so that the error performance index function... By finding the minimum value, the adaptive parameter value of the feedback controller can be obtained.

[0034] In step 5, the adaptive feedback controller The formula is as follows:

[0035]

[0036] in, It is the adaptive value of the feedback controller parameter, ω. z1 and ω z2 These represent the first and second zeros of the feedback controller, ω. p1 and ω p2 These represent the first and second poles of the feedback controller, respectively.

[0037] Compared with the prior art, the beneficial effects of the present invention are:

[0038] This invention addresses the voltage regulation control problem of a dynamic wireless charging system for electric vehicles based on adaptive loop compensation. By combining a loop compensator designed in the frequency domain with adaptive control of a reference model, the bandwidth and anti-interference capability of the closed-loop system are greatly improved. This enables electric vehicles to not only have excellent control performance during static wireless charging but also to effectively suppress large-scale voltage disturbances caused by the movement of electric vehicles during dynamic wireless charging, thus having broader application prospects. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the voltage regulation control of a dynamic wireless charging system for electric vehicles.

[0040] Figure 2 It is a control block diagram based on adaptive loop compensation;

[0041] Figure 3 It is the equivalent topology of the Buck-type DC-DC converter at the energy receiving end;

[0042] Figure 4 This is a diagram illustrating the static charging voltage regulation control effect of the Buck DC-DC converter at the energy receiving end.

[0043] Figure 5 This is a diagram illustrating the dynamic charging and voltage regulation control effect of the Buck-type DC-DC converter at the energy receiving end. Detailed Implementation

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] This invention discloses a voltage regulation control method for a dynamic wireless charging system for electric vehicles based on adaptive loop compensation. It combines frequency domain-based lead-lag loop compensation and reference model adaptive control to obtain an adaptive feedback controller construction method with better closed-loop control performance, thereby improving the bandwidth and interference suppression capability of the closed-loop system. The method consists of two steps: (1) designing a feedback controller that conforms to the frequency domain design parameters according to the desired phase margin and crossover frequency; (2) using the reference model adaptive control theory to adaptively iterate the parameters of the feedback controller based on the above-designed feedback controller to obtain a feedback controller with better performance.

[0046] The control block diagram of the dynamic wireless charging system for electric vehicles based on adaptive loop compensation of this invention is as follows: Figure 2 As shown, this invention combines frequency-domain-based lead-lag loop compensation with reference model adaptive control to obtain a method for constructing an adaptive feedback controller with better closed-loop control performance, including the following steps:

[0047] Step 1: Establish the transfer function model of the DC-DC converter at the energy receiver end of the electric vehicle dynamic wireless charging system for subsequent controller construction. The equivalent topology of the Buck-type DC-DC converter at the energy receiver end is as follows: Figure 3 As shown;

[0048] In step 1, the mathematical model of the DC-DC converter at the energy receiver of the electric vehicle dynamic wireless charging system is first constructed, and the formula is as follows:

[0049]

[0050]

[0051] Among them, d and v o v buck , and These represent the transient duty cycle, transient output voltage, transient input voltage, transient output capacitor voltage, and transient output inductor current of the Buck-type DC-DC converter at the energy receiver end, respectively, along with D and V. buck These represent the steady-state duty cycle and steady-state input voltage of the Buck-type DC-DC converter at the energy receiving end. and They are respectively and The derivative of .

[0052] A transfer function model of the DC-DC converter is established based on the mathematical model of the DC-DC converter. The formula is as follows:

[0053]

[0054] Where s represents the complex variable in the transfer function model, L b and C b These are the output inductor and output capacitor of the Buck DC-DC converter at the energy receiving end, respectively, V buck R is the steady-state input voltage of the Buck-type DC-DC converter at the energy receiving end, and R is the load resistance.

[0055] Step 2: Based on the transfer function model of the DC-DC converter, construct a feedback controller that meets the preset frequency domain performance requirements according to the desired frequency domain design performance constraints (such as phase margin and crossover frequency).

[0056] In step 2, the feedback controller G c The formula for (s) is as follows:

[0057]

[0058] Where, ω z1 and ω z2 These represent the first and second zeros of the feedback controller, ω. p0 ω p1 and ω p2 These represent the zeros, poles, first pole, and second pole of the feedback controller, respectively.

[0059] The desired frequency domain design performance constraints are as follows:

[0060]

[0061] |L(jω co )|=1

[0062] ∠L(jω co )=-π+φ M

[0063] Where L(s) represents the open-loop transfer function, This represents the transfer function model of a DC-DC converter. and feedback controller G c The product of (s); φ M and ω c o represents the desired phase margin and crossover frequency, respectively; |L(jω) co )| and ∠L(jω co ) represent the open-loop transfer function L(s) at the crossover frequency ω. co The amplitude and phase at the specified point; j represents the imaginary unit.

[0064] Step 3: Combine the reference model adaptive control algorithm to establish a reference model that meets the desired frequency domain performance based on the feedback controller;

[0065] In step 3, the formula for the reference model is as follows:

[0066]

[0067]

[0068] Among them, v m Represents the reference model H dr The output variable of (s), where r represents the reference model H dr The reference input is L(s), where L(s) represents the open-loop transfer function, and the above reference model H... dr (s) enables the system to meet the desired frequency domain design performance constraints in step 2.

[0069] Step 4: Establish the error performance index function between the output of the DC-DC converter and the output of the reference model, determine the adaptive law based on the error performance index function, and solve for the adaptive parameter value that minimizes the error performance index function according to the adaptive law.

[0070] Step 4 is as follows:

[0071] First, we establish an error performance index function for the output of the DC-DC converter compared to the output of the reference model. The formula is as follows:

[0072]

[0073] Where ε represents the output voltage v of the Buck-type DC-DC converter at the energy receiver. o (i.e., system output) and the output variable v of the reference model m The error between them, i.e., ε = v o -v m ;

[0074] Next, based on the error performance index function The adaptive law is constructed as follows:

[0075]

[0076] in, This indicates the adaptive value of the parameters of the feedback controller. The derivative of γ, where γ represents the adaptive gain coefficient, and e represents the difference between the reference input r of the reference model and the output voltage v of the Buck-type DC-DC converter at the energy receiver. o The error between;

[0077] Finally, the adaptive law is solved using the gradient descent method, so that the error performance index function... By finding the minimum value, the adaptive parameter value of the feedback controller can be obtained.

[0078] Step 5: Based on the feedback controller and the adaptive parameter values, obtain the adaptive feedback controller. Use the adaptive feedback controller to control the DC-DC converter at the energy receiving end of the electric vehicle dynamic wireless charging system, thereby realizing the voltage regulation control of the electric vehicle dynamic wireless charging system.

[0079] In step 5, the adaptive feedback controller The formula is as follows:

[0080]

[0081] in, It is the adaptive value of the feedback controller parameter, ω. z1 and ω z2 These represent the first and second zeros of the feedback controller, ω. p1 and ω p2 These represent the first and second poles of the feedback controller, respectively.

[0082] The static charging voltage regulation effect of the above controller is as follows: Figure 4 As shown. The dynamic charging voltage regulation control effect of the controller is as follows. Figure 5 As shown.

[0083] In summary, this invention integrates loop compensation theory based on frequency domain design and reference model adaptive control theory. First, using loop compensation theory, a loop compensation feedback controller that satisfies the desired frequency domain design parameters is obtained. Then, using reference model adaptive control theory, the controller parameters of the loop compensation feedback controller are adaptively updated to obtain the adaptive controller parameters that minimize the error performance index function. Finally, an adaptive loop compensation feedback controller is obtained, realizing the voltage regulation control of the Buck DC-DC converter at the energy receiver of the electric vehicle dynamic wireless charging system. This not only achieves disturbance suppression in static charging scenarios but also achieves wide-range voltage disturbance suppression in dynamic wireless charging scenarios, providing a solution for the voltage regulation control of electric vehicle dynamic wireless charging systems.

[0084] The parts of this invention not described in detail are common knowledge to those skilled in the art.

[0085] Finally, it should be noted that the above embodiments and descriptions are only used to illustrate the technical solutions of the present invention and not to limit it. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the disclosure of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the protection scope of the claims of the present invention.

Claims

1. A voltage regulation control method for a dynamic wireless charging system based on adaptive loop compensation, characterized in that, Includes the following steps: Step 1: Establish the transfer function model of the DC-DC converter at the energy receiver end of the electric vehicle dynamic wireless charging system; Step 2: Based on the transfer function model of the DC-DC converter, design performance constraints according to the desired frequency domain, and construct a feedback controller; Step 3: Combine the reference model adaptive control algorithm with the feedback controller to establish a reference model; Step 4: Establish the error performance index function between the output of the DC-DC converter and the output of the reference model, determine the adaptive law based on the error performance index function, and solve for the adaptive parameter value that minimizes the error performance index function according to the adaptive law. Step 5: Based on the feedback controller and the adaptive parameter values, obtain the adaptive feedback controller. Use the adaptive feedback controller to control the DC-DC converter at the energy receiving end of the electric vehicle dynamic wireless charging system, thereby realizing the voltage regulation control of the electric vehicle dynamic wireless charging system. In step 1, the transfer function model of the DC-DC converter The formula is as follows: Where s represents the complex variable in the transfer function model, and These are the output inductor and output capacitor of the DC-DC converter, respectively. R is the steady-state input voltage of the DC-DC converter, and R is the load resistance. In step 2, the feedback controller The formula is as follows: in, and These represent the first and second zeros of the feedback controller, respectively. , and These represent the zeros, poles, first pole, and second pole of the feedback controller, respectively. The desired frequency domain design performance constraints are as follows: in, Represents the open-loop transfer function. Represent the transfer function model of a DC-DC converter; and These represent the desired phase margin and crossover frequency, respectively. and Represent the open-loop transfer function respectively Crossing frequency The amplitude and phase at the specified point; j represents the imaginary unit; In step 3, the formula for the reference model is as follows: in, Representation of reference model The output variable is r, which represents the reference model. Reference input, Represent the open-loop transfer function; Step 4 specifically involves: First, we establish an error performance index function for the output of the DC-DC converter compared to the output of the reference model. The formula is as follows: in, Indicates the output voltage of the DC-DC converter Output variables of the reference model The error between; Next, based on the error performance index function The adaptive law is constructed as follows: in, This indicates the adaptive value of the parameters of the feedback controller. The derivative, The coefficient represents the adaptive gain coefficient, and e represents the ratio of the reference input r of the reference model to the output voltage of the DC-DC converter. The error between; Finally, the adaptive law is solved using the gradient descent method, so that the error performance index function... By finding the minimum value, the adaptive parameter value of the feedback controller can be obtained. ; In step 5, the adaptive feedback controller The formula is as follows: in, These are the adaptive values ​​of the parameters of the feedback controller. and These represent the first and second zeros of the feedback controller, respectively. and These represent the first and second poles of the feedback controller, respectively.

Images