Electric vehicle wireless charging control system and method based on compound disturbance rejection controller

Abstract

The application discloses a kind of wireless charging control system and method of electric vehicle based on composite anti-interference controller.The data measured by sensor realizes the voltage control of electric vehicle wireless charging system without complex mathematical modeling analysis.The core components of the application include model-free extended state observer module, non-smooth dynamic sliding surface module, composite anti-interference control law module and wireless charging system.Compared with the existing electric vehicle wireless charging control system, the application realizes the control of electric vehicle wireless charging system by introducing general disturbance model and extended state observer module, only relying on single sensor data, and without building complex mathematical model in advance.Combined with state feedback information and feedforward compensation strategy, the accuracy and setting performance of system output voltage are significantly improved, the cost of initial implementation and later maintenance is reduced, and the stability of control system is further enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wireless power transmission for electric vehicles, and particularly relates to a wireless charging control system for electric vehicles and a method thereof based on a composite disturbance rejection controller. BACKGROUND

[0002] As an important part of future transportation, electric vehicles have shown remarkable competitiveness in terms of zero tailpipe emissions, no fossil fuel consumption, efficient energy utilization, easy maintenance, and quiet and comfortable driving experience, bringing new development prospects to the automotive industry. However, electric vehicles have been facing key challenges in long-distance travel, i.e., the limitation of range. Traditional battery charging methods have many problems, including high construction cost of charging infrastructure, limited coverage of charging stations, long charging time, and risk of electric shock during charging, which limit the widespread application of electric vehicles, especially in situations requiring long-distance travel or long-distance driving. With the continuous progress of technology, wireless charging technology for electric vehicles is booming and attracting much attention. Among them, dynamic wireless charging technology has attracted widespread attention because it can continuously provide power to electric vehicles during driving. This technology uses inductors and energy transmitters on the road to transmit power to electric vehicles without the need for plugs or parking charging. This not only solves the problem of charging time, but also improves the convenience of using electric vehicles, providing more travel options for drivers. In summary, dynamic wireless charging technology represents a key direction for the future development of electric vehicles. It is expected to eliminate the range limitation and make electric vehicles more suitable for various travel needs, providing more possibilities for sustainable travel.

[0003] During the driving process of an electric vehicle, the coupling coefficient of the energy transmitting and receiving coils changes significantly with the movement of the vehicle, resulting in fluctuations in the output voltage of the system. Although there are currently various control techniques for controlling the output voltage of the electric vehicle wireless charging system, these existing techniques still have the following problems:

[0004] First, existing wireless charging control methods fail to effectively suppress output voltage fluctuations during dynamic wireless charging. These methods mainly rely on feedback control of measured signals, however, feedback control cannot suppress disturbances in a timely and complete manner. In dynamic wireless charging systems, the coupling coefficient of the transmitting and receiving coils often changes widely, and external disturbances increase in a strong magnetic field environment, which poses a great challenge to the control of the output voltage of the system.

[0005] Second, the existing control method of electric vehicle wireless charging system needs to establish a clear mathematical model and prior information, but it takes a lot of work and time cost to establish these clear mathematical models. In addition, these model information will also change due to factors such as parameter drift, parasitic resistance and external disturbance. Therefore, it is of great significance to design a single sensor model-free control method that does not rely on model prior information to improve the control performance of wireless charging system.

[0006] Third, the output voltage control method of the existing electric vehicle dynamic wireless charging system usually only relies on one of the feedback control or feedforward control strategies. These single control strategies do not fully utilize the system state, especially in the case of large-scale and continuous changes in state information and disturbance information in dynamic wireless charging system. Therefore, designing a composite disturbance rejection controller based on feedback suppression and feedforward compensation will greatly improve the output regulation ability of dynamic wireless charging system. SUMMARY

[0007] In order to overcome the technical difficulties faced by the current electric vehicle wireless charging system control method, the present application aims to build a model-free voltage controller for electric vehicle wireless charging system. The controller not only realizes the accurate control of the output voltage of the wireless charging system, but also effectively suppresses the fluctuation of the output voltage of the dynamic wireless charging system. It is worth noting that the controller does not need to establish a detailed mathematical model of the system, nor does it need additional sensors, thereby greatly reducing the implementation cost. By using the present application, the performance of electric vehicle wireless charging in complex environment is significantly improved.

[0008] To achieve the above objectives, the present application adopts the following technical solutions:

[0009] I. An electric vehicle wireless charging control system based on a composite disturbance rejection controller

[0010] The control system includes a model-free extended state observer module, a non-smooth dynamic sliding surface module and a composite disturbance rejection control law module. The input end of the composite disturbance rejection control law module is connected to the output end of the model-free extended state observer module and the output end of the non-smooth dynamic sliding surface module, respectively. The desired output voltage signal is also input to the composite disturbance rejection control law module. The output end of the composite disturbance rejection control law module is connected to the electric vehicle wireless charging system, the input end of the model-free extended state observer module and the input end of the non-smooth dynamic sliding surface module, respectively. The measured output voltage of the electric vehicle wireless charging system is also input to the model-free extended state observer module. The output end of the model-free extended state observer module is also connected to the input end of the non-smooth dynamic sliding surface module.

[0011] The model-free extended state observer module comprises a model-free extended state observer satisfying the following formula:

[0012]

[0013] wherein, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer derivative of the estimated value, and respectively represent the output voltage first-order differential state and the corresponding derivative estimated by the model-free extended state observer, represents the derivative of the lumped disturbance estimated by the model-free extended state observer, ω0 represents a positive observer gain coefficient, represents a calibrated control gain, and μ represents an output control signal.

[0014] The non-smooth dynamic sliding mode surface module comprises a dynamic sliding mode surface and its approach law, and the formula is as follows:

[0015]

[0016]

[0017] wherein, represents the dynamic sliding mode surface and the derivative of the dynamic sliding mode surface, c represents a voltage tracking error gain coefficient, and e represents a voltage tracking error, represents an external expected output voltage signal, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, and ε represents a high-frequency switching gain, and sgn() represents a sign function.

[0018] The composite disturbance rejection control law module comprises a composite disturbance rejection control law, and the formula is as follows:

[0019]

[0020] wherein, represents the expected output voltage signal and the second-order derivative of the expected output voltage signal, and c represents a voltage tracking error gain coefficient, respectively represent the first-order voltage differential state and the lumped disturbance estimated by the model-free extended state observer, and μ represents an output control signal.

[0021] II. An electric vehicle wireless charging control method based on a composite disturbance rejection controller

[0022] Firstly, the model-free extended state observer, the non-smooth dynamic sliding surface and the compound disturbance rejection control law are constructed. The measured output voltage of the electric vehicle wireless charging system is taken as the input signal of the model-free extended state observer, and the control signal output by the compound disturbance rejection control law is taken as the input signal of the model-free extended state observer and the input signal of the non-smooth dynamic sliding surface. The output signal of the model-free extended state observer is taken as the input signal of the non-smooth dynamic sliding surface and the input signal of the compound disturbance rejection control law. The output signal of the non-smooth dynamic sliding surface is also taken as the input signal of the compound disturbance rejection control law, so as to realize the electric vehicle wireless charging control.

[0023] The model-free extended state observer satisfies the following formula:

[0024]

[0025] Among them, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer derivative, and respectively represent the first-order differential state of the output voltage estimated by the model-free extended state observer and the corresponding derivative, represents the derivative of the lumped disturbance estimated by the model-free extended state observer, and ω0 represents a positive observer gain coefficient, represents a calibrated control gain, and μ represents an output control signal.

[0026] The non-smooth dynamic sliding surface includes a dynamic sliding surface and its reaching law, and the formula is as follows:

[0027]

[0028]

[0029] Among them, represents the dynamic sliding surface and the derivative of the dynamic sliding surface, c represents a voltage tracking error gain coefficient, and e represents a voltage tracking error, represents an external expected output voltage signal, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, and ε represents a high-frequency switching gain, and sgn() represents a sign function.

[0030] The formula of the compound disturbance rejection control law is as follows:

[0031]

[0032] wherein, represents the desired output voltage signal and the second derivative of the desired output voltage signal, c represents the voltage tracking error gain coefficient, are the first-order voltage differential state and the lumped disturbance estimated by the model-free extended state observer, respectively, and μ represents the output control signal.

[0033] Compared with the prior art, the present application has the following remarkable beneficial effects:

[0034] First, the present application fully considers the dynamic wireless charging application scenario, and effectively deals with the uncertainty of the complex circuit model and external disturbance in the dynamic wireless charging system by introducing the design of the model-free extended state observer. This technical innovation provides the controller with stronger anti-interference performance, enabling it to better cope with various interference factors and thus improving the stability of the system.

[0035] Second, the present application successfully eliminates the dependence on specific mathematical models and prior information of the model by designing a nonlinear general state space model and a general disturbance model, and at the same time, it eliminates the need for additional input voltage, current sensors and coupling coefficient sensors. This technical innovation not only saves implementation costs, but also enhances the adaptability of the system in complex environments.

[0036] Third, the present application combines the feedforward disturbance compensation and the non-smooth feedback suppression strategies, develops a composite anti-disturbance controller, improves the tracking performance and anti-disturbance performance of the controller, and effectively suppresses the voltage fluctuations that occur during the dynamic wireless charging process. This technology further improves the response speed and stability of the dynamic wireless charging system. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a structural diagram of the designed composite anti-disturbance controller.

[0038] Figure 2 is a static wireless charging process step voltage response effect diagram.

[0039] Figure 3 is a static wireless charging process step voltage response time diagram.

[0040] Figure 4 is a dynamic wireless charging process control input signal effect diagram.

[0041] Figure 5 is a dynamic wireless charging process output voltage fluctuation suppression effect diagram.

[0042] Figure 6is a dynamic wireless charging process no model disturbance estimation effect diagram. DETAILED DESCRIPTION

[0043] The application will be described in detail below with reference to the accompanying drawings.

[0044] The electric vehicle wireless charging control system based on the composite disturbance rejection controller is a composite disturbance rejection controller. The design of the controller does not need to establish a detailed mathematical model of the system, and the accurate control of the output voltage of the wireless charging system can be realized by combining the state feedback information and the feedforward compensation strategy, and the fluctuation of the output voltage in the dynamic wireless charging process is effectively suppressed. As shown in Figure 1 The control system includes a no model extended state observer module, a non-smooth dynamic sliding surface module and a composite disturbance rejection control law module. The input end of the composite disturbance rejection control law module is connected with the output end of the no model extended state observer module and the output end of the non-smooth dynamic sliding surface module respectively, and the external expected output voltage signal is also used as the input of the composite disturbance rejection control law module. The output end of the composite disturbance rejection control law module is connected with the electric vehicle wireless charging system, the input end of the no model extended state observer module and the input end of the non-smooth dynamic sliding surface module respectively, and the measured output voltage of the electric vehicle wireless charging system is also used as the input of the no model extended state observer module. The output end of the no model extended state observer module is also connected with the input end of the non-smooth dynamic sliding surface module. Through this control system, the highly accurate control of the output voltage of the electric vehicle wireless charging system is realized without the need of establishing a complex mathematical model in advance. At the same time, the control module can also significantly improve the voltage output capability of the wireless charging system, thereby further improving the system performance. The application is expected to overcome the challenges in the voltage control of the current electric vehicle wireless charging system, improve the performance and stability of the system, and reduce the implementation cost, thereby providing a more reliable solution for the electric energy transmission of electric vehicles.

[0045] The nonlinear general state space model of the electric vehicle wireless charging system control circuit is described by the following equation group:

[0046]

[0047] Wherein, V out ,V d respectively represent the measured output voltage and its differential, μ represents the output control signal, σ0 represents the model uncertainty and external disturbance, σ(V out ,V d , μ, σ0) represents the general disturbance model, represents the nominal control gain, b represents the actual control gain, A1, A2 represent unknown state gain coefficients, represents the derivative of V d .

[0048] The model-free extended state observer module comprises a model-free extended state observer satisfying the following formula:

[0049]

[0050] wherein, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer derivative of the estimated value, and respectively represent the output voltage first-order differential state and the corresponding derivative estimated by the model-free extended state observer, represents the derivative of the estimated value of the lumped disturbance estimated by the model-free extended state observer, ω0 represents a positive observer gain coefficient, represents a calibrated control gain, and μ represents an output control signal.

[0051] The non-smooth dynamic sliding surface module comprises a dynamic sliding surface and its reaching law, and the formula is as follows:

[0052]

[0053]

[0054] wherein, represents the dynamic sliding surface and the derivative of the dynamic sliding surface, c represents a voltage tracking error gain coefficient, and e represents a voltage tracking error, represents an external expected output voltage signal, represents the estimated value of the measured output voltage V out estimated by the model-free extended state observer, ε represents a high-frequency switching gain, and sgn() represents a sign function, satisfying |s| sgn(s) = s.

[0055] The composite disturbance rejection control law module comprises a composite disturbance rejection control law, and the formula is as follows:

[0056]

[0057] wherein, represents the expected output voltage signal and the second-order derivative of the expected output voltage signal, c represents a voltage tracking error gain coefficient, respectively represent the first-order voltage differential state and the lumped disturbance estimated by the model-free extended state observer, and are obtained by the model-free extended state observer. μ represents an output control signal, which is used to control the output voltage of the electric vehicle dynamic wireless charging system.

[0058] The wireless charging control method for electric vehicles based on a composite disturbance rejection controller includes the following steps:

[0059] First, a model-free extended state observer, a non-smooth dynamic sliding surface, and a composite disturbance rejection control law are constructed. The measured output voltage of the electric vehicle wireless charging system serves as the input signal of the model-free extended state observer. The control signal output by the composite disturbance rejection control law acts on the electric vehicle wireless charging system and also serves as the input signal of the model-free extended state observer and the non-smooth dynamic sliding surface. The output signal of the model-free extended state observer serves as the input signal of the non-smooth dynamic sliding surface and the composite disturbance rejection control law. The output signal of the non-smooth dynamic sliding surface also serves as the input signal of the composite disturbance rejection control law, thereby realizing the wireless charging control of the electric vehicle.

[0060] The experimental results are presented in Figures 2 to 6 middle. Figure 2 a, Figure 2 b, Figure 2 c and Figure 2 The figures d illustrate the output voltage step response during static wireless charging under the control of four methods: Proportional Integral-Derivative (PID) control with only feedback suppression, conventional Sliding Mode Control (SMC) control with only feedback suppression, conventional Active Disturbance Rejection Control (ADRC) control with only feedforward compensation, and the composite disturbance rejection control (CADC) method proposed in this invention. The relative positions of the wireless charging transmitting and receiving coils remain stationary. In this scenario, the desired output voltage switches multiple times between 36V and 48V, and the established controller-based wireless charging system effectively tracks the desired output voltage in all cases. Figure 3 The response time of the process is specifically demonstrated using only the traditional proportional-integral-derivative control method with a feedback suppression strategy. Figure 3 The value of a) is 51 milliseconds, which is lower than that of traditional sliding mode control methods that only employ feedback suppression strategies. Figure 3 b) is 18 milliseconds, which is less than the traditional active disturbance rejection control method that only uses feedforward compensation strategy ( Figure 3 The c) is 26 milliseconds, while the proposed composite disturbance rejection control method ( Figure 3 The value of d) is 18 milliseconds. Compared with traditional integral-derivative control methods and active disturbance rejection control methods, the composite disturbance rejection control method proposed in this invention exhibits excellent step tracking performance.

[0061] Figures 4 to 6This demonstrates the experimental results of dynamic wireless charging for electric vehicles. In this process, an energy receiving coil mounted on the electric vehicle is initially aligned with the first energy transmitting coil. As the electric vehicle moves, the energy receiving coil gradually moves away from the first energy transmitting coil, gradually approaches it, and eventually aligns with the next energy transmitting coil. Figure 4 a, Figure 4 b, Figure 4 c and Figure 4 The figures d respectively demonstrate the control input signal effects during dynamic wireless charging under the control of the proportional-integral-derivative (PID) control method with only feedback suppression strategy, the traditional sliding mode control (SMC) method with only feedback suppression strategy, the traditional active disturbance rejection control (ADRC) method with only feedforward compensation strategy, and the composite disturbance rejection control method (CADC) proposed in this invention. Compared with the traditional sliding mode control method, the proposed composite disturbance rejection control method shows excellent control signal chatter suppression performance, which will effectively reduce actuator wear and additional power consumption. Figure 5 a, Figure 5 b, Figure 5 c and Figure 5 The figures d respectively demonstrate the output voltage fluctuation suppression effect during dynamic wireless charging under the control of the proportional-integral-derivative (PID) control method with only feedback suppression strategy, the traditional sliding mode control (SMC) method with only feedback suppression strategy, the traditional active disturbance rejection control (ADRC) method with only feedforward compensation strategy, and the composite disturbance rejection control method (CADC) proposed in this invention. The proposed composite disturbance rejection control method shows better fluctuation suppression performance compared with the other three methods, ensuring stable and continuous power transmission of electric vehicles during dynamic wireless charging. Figure 6 The observation performance of the model-free extended state observer is demonstrated, showing that it can effectively and accurately estimate perturbations regardless of their changes before and after the dynamic wireless charging process. These results indicate that the proposed method can achieve output voltage control without establishing a detailed mathematical model and effectively suppresses output voltage fluctuations during dynamic wireless charging. These experimental results strongly support the effectiveness and superior performance of the invention and further confirm the broad application potential of the proposed composite disturbance rejection control method in electric vehicle wireless charging systems.

[0062] This invention is not limited to this embodiment. Any equivalent concept or modification within the technical scope disclosed in this invention shall be included within the protection scope of this invention.

Claims

1. A composite disturbance rejection controller based electric vehicle wireless charging control system, characterized in that, The module comprises a model-free extended state observer, a non-smooth dynamic sliding mode surface and a composite disturbance rejection control law module; the input end of the composite disturbance rejection control law module is connected with the output end of the model-free extended state observer and the output end of the non-smooth dynamic sliding mode surface respectively, and the expected output voltage signal is also used as the input of the composite disturbance rejection control law module; the output end of the composite disturbance rejection control law module is connected with the electric vehicle wireless charging system, the input end of the model-free extended state observer and the input end of the non-smooth dynamic sliding mode surface respectively, and the measured output voltage of the electric vehicle wireless charging system is also used as the input of the model-free extended state observer; the output end of the model-free extended state observer is also connected with the input end of the non-smooth dynamic sliding mode surface; The model-free extended state observer module comprises a model-free extended state observer satisfying the following formula: wherein represents the estimated measurement output voltage , represents the estimated measurement output voltage , represents the derivative of the estimated measurement output voltage , represents the estimated output voltage first order differential state and the corresponding derivative, respectively, estimated by the model-free extended state observer, represents the derivative of the estimated lumped disturbance , represents a positive definite observer gain coefficient, represents a nominal control gain, represents the output control signal; The non-smooth dynamic sliding mode surface module comprises a dynamic sliding mode surface and its approaching law, and the formula is as follows: wherein, denotes a dynamic sliding surface and a derivative of the dynamic sliding surface, denotes a voltage tracking error gain coefficient, denotes a voltage tracking error, denotes an external desired output voltage signal, denotes an estimated value of the measured output voltage estimated by the model-free extended state observer, denotes a high frequency switching gain, denotes a sign function; The composite disturbance rejection control law module comprises a composite disturbance rejection control law, and the formula is as follows: wherein denotes the desired output voltage signal and the second derivative of the desired output voltage signal, denotes the voltage tracking error gain coefficient, are the first order voltage derivative state and the lumped disturbance estimated by the model-free extended state observer, respectively, denotes the output control signal.

2. A control method for wireless charging of an electric vehicle based on a composite disturbance rejection controller, characterized in that, The method comprises the following steps: First, a model-free extended state observer, a non-smooth dynamic sliding mode surface and a composite disturbance rejection control law are constructed; the measured output voltage of the electric vehicle wireless charging system is used as the input signal of the model-free extended state observer, the control signal output by the composite disturbance rejection control law is used for the electric vehicle wireless charging system, and is also used as the input signal of the model-free extended state observer and the input signal of the non-smooth dynamic sliding mode surface; the output signal of the model-free extended state observer is used as the input signal of the non-smooth dynamic sliding mode surface and the input signal of the composite disturbance rejection control law; the output signal of the non-smooth dynamic sliding mode surface is also used as the input signal of the composite disturbance rejection control law, so as to realize the electric vehicle wireless charging control; The model-free extended state observer satisfies the following formula: wherein represents the estimated measurement output voltage , represents the estimated measurement output voltage , represents the derivative of the estimated measurement output voltage and represents the estimated output voltage first order differential state and the corresponding derivative, respectively, estimated by the model-free extended state observer, represents the estimated lumped disturbance , represents a positive definite observer gain coefficient, represents a nominal control gain, represents the output control signal; The non-smooth dynamic sliding mode surface comprises a dynamic sliding mode surface and its approaching law, and the formula is as follows: wherein, denotes a dynamic sliding surface and a derivative of the dynamic sliding surface, denotes a voltage tracking error gain coefficient, denotes a voltage tracking error, denotes an external desired output voltage signal, denotes an estimated value of the measured output voltage estimated by the model-free extended state observer, denotes a high frequency switching gain, denotes a sign function; The formula of the composite disturbance rejection control law is as follows: wherein denotes the desired output voltage signal and the second derivative of the desired output voltage signal, denotes the voltage tracking error gain coefficient, are the first order voltage derivative state and the lumped disturbance estimated by the model-free extended state observer, respectively, denotes the output control signal.

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