An electric vehicle dynamic wireless charging system output voltage control method

Abstract

The application discloses an output voltage control method of an electric vehicle dynamic wireless charging system. The DC-DC circuit of the energy transmission transmitting end is designed, and a linear active disturbance rejection controller and a hybrid controller are introduced. The linear active disturbance rejection controller observes the estimated values of the state variables and disturbances of the DC-DC circuit through an extended state observer, forms a first control quantity and a disturbance compensation link to output a second control quantity through a linear state feedback control law, and is used for ensuring the constant input voltage of the full-bridge inverter circuit. The hybrid controller outputs the switching frequency and the phase shift angle to adjust the stability of the load output voltage and the wide adjustment range of the system voltage gain. The application significantly improves the constant voltage adjustment performance and the anti-interference performance of the system, reduces the implementation cost of the adjustment system elements, further enhances the stability and robustness of the system, and provides an effective solution for the stable operation of the electric vehicle dynamic wireless charging system.

Description

Technical Field

[0001] This invention belongs to the field of dynamic wireless charging technology and relates to a dynamic wireless charging control method for electric vehicles, and more particularly to a method and system for controlling the output voltage of a dynamic wireless charging system for electric vehicles. Background Technology

[0002] The range anxiety and charging convenience of electric vehicles have always been the primary factors restricting their large-scale adoption. Dynamic Wireless Power Transfer (DWPT) technology, as an emerging charging method, enables uninterrupted power replenishment for electric vehicles without direct plugging and unplugging during operation, effectively alleviating range anxiety and improving charging convenience.

[0003] Dynamic wireless charging (DWPT) technology enables the transfer of electrical energy between mobile devices by deploying energy transmission transmitters along the moving path of the energy transmission receiver. However, in practical applications, dynamic wireless charging systems face numerous challenges, such as positional misalignment between the transmitter and receiver, variations in load resistance, and the need to maintain stable output voltage and high transmission efficiency under conditions of fluctuating system voltage gain. These factors can all lead to unstable output voltage, affecting charging efficiency and quality. Therefore, researching dynamic wireless charging systems with constant voltage output characteristics that resist load and voltage gain shifts is crucial for improving the range of electric vehicles and enhancing user experience.

[0004] For example, Chinese patent document CN118971402A discloses a dual-frequency dynamic wireless charging system and method. First, two adjacent transmitting coils at the transmitting end are configured with different resonant frequencies. Second, through clever topology design at the receiving end, the receiving end has two resonant frequency points corresponding to the two resonant frequencies of the transmitting end. This makes the coupling magnetic field of any transmitting channel to its adjacent transmitting channels exhibit high resistance, avoiding crosstalk between transmitting coils and improving the system's transmission efficiency. However, when there are jumps in the system input voltage or load impedance, constant voltage or constant current output cannot be guaranteed.

[0005] Currently, dynamic wireless charging systems have limited ability to respond quickly to various disturbances during vehicle operation, such as speed changes, lateral drift, and variations in system input voltage and load. This can lead to insufficient system response speed, resulting in fluctuations and instability in charging power. Furthermore, some constant voltage control algorithms (such as PI control) cannot achieve precise control of the charging voltage, affecting the control accuracy of the device. Simultaneously, dynamic wireless charging systems require high-precision sensors, controllers, and actuators; therefore, frequent hardware replacements increase system costs. Thus, researching a faster and more effective control method is of greater significance. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems existing in the prior art and provide a method for controlling the output voltage of a dynamic wireless charging system for electric vehicles. This invention enhances the speed and stability of system control by introducing a linear active disturbance rejection controller (LADRC), a frequency converter, and a phase shifter at the energy transmission transmitter. Simultaneously, it utilizes a multi-transmitter-single-receiver magnetic coupling mechanism design and an LCC-S resonant converter network to address the output voltage fluctuation problem caused by the segmented transmitter device. This invention significantly improves the system's constant voltage regulation performance and anti-interference performance, while also reducing the implementation cost of adjusting system components, further enhancing the system's stability and robustness. This invention improves the constant voltage output performance of ordinary wireless charging systems, providing an effective solution for the stable operation of dynamic wireless charging systems for electric vehicles, and has a significant impact on the field of dynamic wireless charging technology.

[0007] The specific technical solution adopted in this invention is as follows:

[0008] I. A method for controlling the output voltage of a dynamic wireless charging system for electric vehicles

[0009] A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply in the dynamic wireless charging system for electric vehicles. The dynamic wireless charging system for electric vehicles is connected to the power grid. The LADRC controller controls the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit.

[0010] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage.

[0011] The DC-DC circuit is a Boost converter chopper circuit.

[0012] The LADRC controller includes a linear extended state observer and a linear state feedback control law. The linear state feedback control law uses the full-bridge inverter circuit input voltage reference value U... d ′ cref The input voltage U of the full-bridge inverter circuit output by the linear expansion state observer. d ′ c The difference between the estimated value z1 and the first control value u0 is output as the feedback control quantity.

[0013] Based on the estimated total disturbance value z2 output by the linear extended state observer, the first control quantity u0 is perturbated and then the second control quantity u is obtained. The second control quantity u is used to generate the PWM drive signal for the switching transistors in the DC-DC circuit and control the DC-DC circuit. The linear extended state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage U of the full-bridge inverter circuit... d ′ c Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage U of the full-bridge inverter circuit. d ′ c The estimated values ​​z1 and z2 of the total disturbance f are given by the following formulas:

[0014]

[0015] in, The input voltage U of the full-bridge inverter circuit d ′ c The differential of the estimated value z1, β1 and β2 are the differentials of the estimated total disturbance f, z2; β1 and β2 are the two control coefficients of the linear extended state observer.

[0016] The second control quantity u is obtained by performing disturbance compensation on the first control quantity u0 based on the estimated value z2 of the total disturbance quantity f output by the linear extended state observer, specifically satisfying the following formula:

[0017]

[0018] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically including:

[0019] First, calculate the voltage error U between the actual output voltage and the given output voltage of the system. error Then the first PI controller determines the voltage error U. error Calculate the phase shift angle D; then, based on the voltage error U... error The switching frequency f is obtained by calculating the phase shift angle D. s Based on the phase shift angle D and the switching frequency f s The corresponding PWM drive signal for the switching transistor is generated to stabilize the output voltage of the control system.

[0020] The control method further includes:

[0021] The four diodes and capacitors in parallel in the rectifier circuit of the wireless charging system are replaced with four controllable MOSFET switches. A second single hybrid controller is used to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit according to the system output voltage, thereby stabilizing the system output voltage.

[0022] The method of using a second single-hybrid controller to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically includes:

[0023] First, calculate the voltage error U between the actual output voltage and the given output voltage of the system. error Then the second PI controller, based on the voltage error U... error Calculate the phase shift angle D; then, based on the voltage error U... error The switching frequency f is obtained by calculating the phase shift angle D. s Based on the phase shift angle D and the switching frequency f s The corresponding PWM drive signal for the switching transistor is generated to stabilize the output voltage of the control system.

[0024] II. An output voltage control device for a dynamic wireless charging system for electric vehicles

[0025] A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply of the dynamic wireless charging system for electric vehicles, and the dynamic wireless charging system for electric vehicles is connected to the power grid.

[0026] The LADRC controller is used to control the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit.

[0027] The first single hybrid controller is used to perform frequency conversion and phase shift control on the full-bridge inverter circuit according to the system output voltage, thereby stabilizing the system output voltage.

[0028] III. An output voltage control device for a dynamic wireless charging system for electric vehicles

[0029] A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply in the dynamic wireless charging system for electric vehicles, and the dynamic wireless charging system for electric vehicles is connected to the power grid; and the four diodes and capacitors in parallel in the rectifier circuit of the wireless charging system are replaced with four controllable MOSFET switches.

[0030] The LADRC controller is used to control the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit.

[0031] The first single hybrid controller is used to perform frequency conversion and phase shift control on the full-bridge inverter circuit according to the system output voltage, thereby stabilizing the system output voltage.

[0032] The second single hybrid controller is used to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit according to the system output voltage, thereby stabilizing the system output voltage.

[0033] Compared with the prior art, the present invention brings the following beneficial effects:

[0034] This invention establishes a constant-voltage topology by introducing an LCC-S resonant converter network. Secondly, it introduces an LADRC controller to maintain a constant voltage even during input voltage fluctuations in the full-bridge inverter circuit. Thirdly, it introduces a hybrid controller (including frequency conversion control and phase-shift control) to adjust the switching frequency and phase angle of the full-bridge inverter circuit at the energy transmission transmitter, thereby improving the stability of the load output voltage and enabling wide-range adjustment of the system voltage gain. This enhances the system's constant-voltage regulation performance and anti-interference capabilities, while also reducing the implementation cost of adjusting system components, further strengthening the system's stability and robustness.

[0035] Furthermore, when the DC input voltage of the electric vehicle dynamic wireless charging system in this invention experiences a step increase or a step decrease (similarly), the load output voltage can quickly reach the ideal voltage drop, thus satisfying the speed requirement of wireless power transmission.

[0036] Furthermore, the electric vehicle dynamic wireless charging system of this invention, with the LADRC controller combined with a hybrid controller, enables the system to stably achieve constant voltage control and a wide range of voltage gain variations. Attached Figure Description

[0037] Figure 1 This is a topology diagram of the LADRC control combined with a single-hybrid control system for the electric vehicle dynamic wireless charging system of the present invention;

[0038] Figure 2 This is a topology diagram of the LADRC control combined with dual hybrid control for the electric vehicle dynamic wireless charging system of the present invention;

[0039] Figure 3 This is a simplified model diagram of the LCC resonant converter in the electric vehicle dynamic wireless charging system of the present invention;

[0040] Figure 4 This is a flowchart of the LADRC controller of the electric vehicle dynamic wireless charging system of the present invention;

[0041] Figure 5 This is a graph showing the relationship between the load output voltage and frequency ratio under different phase shift angles according to the present invention;

[0042] Figure 6 The diagram shows the DC input voltage and load output voltage response effects when using single-hybrid, dual-hybrid, and LADRC control combined with single-hybrid and LADRC control combined with dual-hybrid control according to the present invention.

[0043] Figure 7 The diagram shows the voltage gain response of the system under single-hybrid, dual-hybrid, and LADRC control combined with single-hybrid and LADRC control combined with dual-hybrid control according to the present invention. Detailed Implementation

[0044] The present invention will be further described and illustrated below with reference to the accompanying drawings. It should be noted that the following embodiments are merely for the purpose of aiding understanding the present invention, and the resonant converter network can be combined accordingly without mutual conflict. The dynamic wireless charging system includes a power supply, a DC-DC circuit, an energy transmission transmitting device (including a high-frequency inverter circuit, an LCC resonant converter network, and an energy transmitting coil), an energy transmission receiving device (including an energy receiving coil, an S-resonant converter network, a rectifier circuit, and a control circuit), and a load impedance.

[0045] Example 1

[0046] This invention proposes a method for controlling the output voltage of a dynamic wireless charging system for electric vehicles. The control method includes:

[0047] like Figure 1 As shown, a dynamic wireless charging system for electric vehicles is constructed, and an LCC-S resonant converter network is introduced to determine the topology with constant voltage characteristics. A DC-DC circuit, which is a Boost converter, is added between the full-bridge inverter circuit (DWCS) and the DC power supply. The dynamic wireless charging system for electric vehicles is connected to the power grid, and the LADRC controller controls the DC-DC circuit according to the system input voltage, that is, it stabilizes the output voltage of the DC-DC circuit, thereby stabilizing the input voltage of the full-bridge inverter circuit.

[0048] The simplified circuit model of the dynamic wireless charging system topology based on the LCC-S resonant transform network has the following mesh current matrix equation:

[0049]

[0050] Where ω is the system's operating angular frequency, M is the mutual inductance of the two resonant inductors, and L... p and L s C is the resonant inductance between the energy transmission transmitter and the energy transmission receiver. p and C s L is the resonant capacitance between the energy transmission transmitter and the energy transmission receiver. c1 I is the compensating inductor for the energy transmission transmitter.p and I s I is the resonant inductor current between the energy transmission transmitter and the energy transmission receiver. c1 To compensate for the inductor current at the energy transmission transmitter, U ab U is the input current of the energy transmission and transmitting device. cd R is the output current of the energy transmission and receiving device. eq This is the system load impedance.

[0051] like Figure 4 As shown, the LADRC controller includes a Linear Extended State Observer (LESO) and a Linear State Feedback Control Law (LSEF). The Linear State Feedback Control Law sets the input voltage reference value U of the full-bridge inverter circuit as the input voltage reference value. d ′ cref The input voltage U of the full-bridge inverter circuit output by the linear expansion state observer. d ′ c The difference between the estimated value z1 and the control quantity is used as the feedback control quantity and the first control quantity u0 is output. The control quantity u0 formed by the linear proportional controller LESF can be expressed as:

[0052] u0 = k p (U d ′ cref -z1)

[0053] In the above formula, k p U represents the proportional coefficient of the proportional controller. d ′ cref This indicates the reference value of the input voltage for the full-bridge inverter circuit.

[0054] Based on the estimated value z2 of the total disturbance f output by the linear expansion state observer, the first control quantity u0 is subjected to disturbance compensation to obtain the second control quantity u. The PWM drive signal of the switching transistor in the DC-DC circuit is generated based on the second control quantity u and the DC-DC circuit is controlled.

[0055] The linear expansion state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage U of the full-bridge inverter circuit. d ′ c (i.e., the output voltage of the DC-DC circuit) Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage U of the full-bridge inverter circuit. d ′ c The estimated values ​​z1 and z2 of the total disturbance f are given by the following formulas:

[0056]

[0057] in, The input voltage U of the full-bridge inverter circuit d′ c The differential of the estimated value z1, β1 and β2 are the differentials of the estimated total disturbance f, z2; β1 and β2 are two control coefficients of the linear extended state observer, both of which are adjustable parameters.

[0058] The second control quantity u is obtained by performing disturbance compensation on the first control quantity u0 based on the estimated value z2 of the total disturbance quantity f output by the linear extended state observer, specifically satisfying the following formula:

[0059]

[0060] The LADRC controller transforms system uncertainties (including external and internal disturbances) into an observable state. It estimates the state information of these disturbances in real time through a linear extended state observer (LESO) and compensates for them in real time using a linear state feedback control law (LSEF). This enables the LADRC to achieve stable control of the input voltage of the full-bridge inverter circuit even when the DC-DC circuit module faces complex disturbances and nonlinear characteristics.

[0061] The Linear Extended State Observer (LESO) expands the total disturbance into a new state variable of the system and estimates it. Based on this, further operations such as system feedback control and disturbance compensation are performed. In LADRC, the ESO can be transformed into a Linear Extended State Observer (LESO) by linearizing the complex nonlinear function with parameters, and its parameters are related to the observer bandwidth. This also enables the estimation of system state and the observation of disturbances.

[0062] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage.

[0063] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically including:

[0064] First, calculate the voltage error U between the actual output voltage and the given output voltage of the system. error Then the first PI controller determines the voltage error U. error The phase shift angle D is calculated; the proportional coefficient of the first PI controller is set to 0.001, and the integral coefficient is set to 0.8. Then, based on the voltage error U... error The switching frequency f is obtained by calculating the phase shift angle D. s The phase shift angle D and the switching frequency f s The data is loaded into the phase shift register and the period register respectively; based on the phase shift angle D and the switching frequency f... sA PWM drive signal is generated for the corresponding switching transistor to stabilize the system's output voltage, which is a single-hybrid control method. After a step change in the input voltage, the load output voltage has an overshoot value and then tends to be constant.

[0065] like Figure 3 As shown, only the LCC resonant converter in the resonant converter network is considered. Where, U ab nU is the equivalent input voltage of the LCC resonant converter. sec R is the equivalent output voltage of the LCC resonant converter. ac This is the equivalent resistance.

[0066] When the controller employs frequency conversion control and phase shift control, the switching frequency and phase shift angle of the high-frequency inverter circuit jointly affect the voltage gain of the dynamic wireless charging system, expressed as the duty cycle. This represents the magnitude of the phase shift angle, where T on Indicates half a switching cycle The duration for the diagonal MOSFETs to conduct simultaneously. Assume the system voltage gain. The output voltage U of the energy transmission receiver out With the input voltage U of the energy transmission transmitter dc The ratio. Based on the fundamental component approximation method and Fourier series expansion, the effective value of the fundamental component of the input signal of the LCC-S resonant converter network under frequency conversion control and phase shift control can be obtained. Similarly, the output voltage U of the energy transmission receiver cd RMS value of fundamental component under frequency conversion control and phase shift control The voltage U on the transformer at the energy transmission transmitter sec for:

[0067]

[0068] Then the following formula is derived:

[0069]

[0070] AC equivalent resistance before the rectifier circuit Under frequency conversion control and phase shift control, it is referred to the AC equivalent resistance R of the LCC resonant converter. ac for Where R L Let this be the system load impedance. Also, consider the system voltage gain. Therefore, the transfer function G(jω) of the system voltage gain can be obtained. s ):

[0071]

[0072] Where, ω sIt is the switching angular frequency. The formula derived from the resonant angular frequency is: ω0 is the resonant angular frequency. Substituting the above equation into the transfer function G(jω) of the system voltage gain... s In this context, the following formula exists:

[0073]

[0074] definition This is the ratio of the resonant capacitor to the compensation capacitor. Let be the quality factor of the resonant circuit, then we can solve the quality factor formula simultaneously with... The following formula is obtained:

[0075]

[0076] Therefore, the system voltage gain transfer function G(jω) s This can be simplified to the following formula:

[0077]

[0078] definition f is the ratio of the switching frequency to the resonant frequency, where f s f0 is the switching frequency, f0 is the resonant frequency, and ω is the switching frequency. s ω0 is the switching angular frequency, and ω0 is the resonant angular frequency. Figure 3 Topologically, the mesh current equations are derived as follows:

[0079]

[0080] According to the formula The resonant frequency derivation formula and equation (8) yield the system voltage gain and output voltage formulas under the hybrid controller, respectively:

[0081]

[0082] The hybrid controller regulates the stability of the load output voltage and the wide range of voltage gain variation by adjusting the switching frequency and phase shift angle of the full-bridge inverter circuit at the energy transfer transmitter. Here, G represents the system voltage gain, and U... out U is the load output voltage, n is the linear transformer coil winding ratio, and U is the load output voltage. dc Where is the DC input voltage of the system, Q is the quality factor of the resonant circuit, and λ = C. p / C c1 C is the ratio of the resonant capacitor to the compensation capacitor. c1 For the compensation capacitor at the energy transmission transmitter, f N For the switching frequency f s With resonant frequency f r The ratio, where D is the magnitude of the phase shift angle, and Io This refers to the current flowing through the system load impedance.

[0083] Let λ = 4, Q = 0.4, n = 1, and plot the graph to obtain 0 < f N <1 and 1<f N When <2, the system output voltage U under the hybrid control method out Curves, such as Figure 5 As shown. This is achieved when the ratio of resonant capacitor to compensation capacitor λ, quality factor Q, linear transformer coil winding ratio n, and the ratio of switching frequency to resonant frequency f are maintained. N Certainly, under the hybrid control method, the load output voltage can be adjusted by changing the phase shift angle D. Based on the above analysis, compared to single frequency converter control or phase shift control, the hybrid control method offers more flexibility in adjusting the load output voltage.

[0084] Example 2

[0085] This invention proposes a method for controlling the output voltage of a dynamic wireless charging system for electric vehicles. The control method includes:

[0086] like Figure 1 As shown, a dynamic wireless charging system for electric vehicles is constructed, and an LCC-S resonant converter network is introduced to determine the topology with constant voltage characteristics. A DC-DC circuit, which is a Boost converter, is added between the full-bridge inverter circuit (DWCS) and the DC power supply. The dynamic wireless charging system for electric vehicles is connected to the power grid, and the LADRC controller controls the DC-DC circuit according to the system input voltage, that is, it stabilizes the output voltage of the DC-DC circuit, thereby stabilizing the input voltage of the full-bridge inverter circuit.

[0087] like Figure 4 As shown, the LADRC controller includes a Linear Extended State Observer (LESO) and a Linear State Feedback Control Law (LSEF). The Linear State Feedback Control Law sets the input voltage reference value U of the full-bridge inverter circuit as the input voltage reference value. d ′ cref The input voltage U of the full-bridge inverter circuit output by the linear expansion state observer. d ′ c The difference between the estimated value z1 and the control quantity is used as the feedback control quantity and the first control quantity u0 is output. The control quantity u0 formed by the linear proportional controller LESF can be expressed as:

[0088] u0 = k p (U d ′ cref -z1)

[0089] In the above formula, k p U represents the proportional coefficient of the proportional controller. d ′ crefThis indicates the reference value of the input voltage for the full-bridge inverter circuit.

[0090] Based on the estimated value z2 of the total disturbance f output by the linear expansion state observer, the first control quantity u0 is subjected to disturbance compensation to obtain the second control quantity u. The PWM drive signal of the switching transistor in the DC-DC circuit is generated based on the second control quantity u and the DC-DC circuit is controlled.

[0091] The linear expansion state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage U of the full-bridge inverter circuit. d ′ c (i.e., the output voltage of the DC-DC circuit) Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage U of the full-bridge inverter circuit. d ′ c The estimated values ​​z1 and z2 of the total disturbance f are given by the following formulas:

[0092]

[0093] in, The input voltage U of the full-bridge inverter circuit d ′ c The differential of the estimated value z1, β1 and β2 are the differentials of the estimated total disturbance f, z2; β1 and β2 are two control coefficients of the linear extended state observer, both of which are adjustable parameters.

[0094] The second control quantity u is obtained by performing disturbance compensation on the first control quantity u0 based on the estimated value z2 of the total disturbance quantity f output by the linear extended state observer, specifically satisfying the following formula:

[0095]

[0096] The LADRC controller transforms system uncertainties (including external and internal disturbances) into an observable state. It estimates the state information of these disturbances in real time through a linear extended state observer (LESO) and compensates for them in real time using a linear state feedback control law (LSEF). This enables the LADRC to achieve stable control of the input voltage of the full-bridge inverter circuit even when the DC-DC circuit module faces complex disturbances and nonlinear characteristics.

[0097] The Linear Extended State Observer (LESO) expands the total disturbance into a new state variable of the system and estimates it. Based on this, further operations such as system feedback control and disturbance compensation are performed. In LADRC, the ESO can be transformed into a Linear Extended State Observer (LESO) by linearizing the complex nonlinear function with parameters, and its parameters are related to the observer bandwidth. This also enables the estimation of system state and the observation of disturbances.

[0098] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage.

[0099] The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically including:

[0100] First, calculate the voltage error U between the actual output voltage and the given output voltage of the system. error Then the first PI controller determines the voltage error U. error The phase shift angle D is calculated; the proportional coefficient of the first PI controller is set to 0.001, and the integral coefficient is set to 0.8. Then, based on the voltage error U... error The switching frequency f is obtained by calculating the phase shift angle D. s The phase shift angle D and the switching frequency f s The data is loaded into the phase shift register and the period register respectively; based on the phase shift angle D and the switching frequency f... s A PWM drive signal is generated for the corresponding switching transistor to stabilize the system's output voltage, which is a single-hybrid control method. After a step change in the input voltage, the load output voltage has an overshoot value and then tends to be constant.

[0101] like Figure 2 As shown, the four diodes and capacitors in parallel in the rectifier circuit of the wireless charging system are replaced with four controllable MOSFET switches. The second single hybrid controller performs frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit according to the system output voltage, thereby stabilizing the system output voltage.

[0102] The method of using a second single-hybrid controller to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically includes:

[0103] First, calculate the voltage error U between the actual output voltage and the given output voltage of the system. error Then the second PI controller, based on the voltage error U... errorThe phase shift angle D is calculated; the proportional coefficient of the second PI controller is set to 0.001, and the integral coefficient is set to 0.8. Then, based on the voltage error U... error The switching frequency f is obtained by calculating the phase shift angle D. s The phase shift angle D and the switching frequency f s The data is loaded into the phase shift register and the period register respectively; based on the phase shift angle D and the switching frequency f... s A PWM drive signal is generated for the corresponding switching transistor to stabilize the system's output voltage. After a step change in the input voltage, the load output voltage fluctuates and gradually becomes constant. Thus, the dynamic wireless charging system employs hybrid control at both the front and back ends, i.e., a dual hybrid control method.

[0104] This invention introduces a LADRC controller and a hybrid controller. The hybrid controller (including frequency conversion control and phase shift control) maintains a constant input voltage to the full-bridge inverter circuit even during a step change in the DC input voltage by adjusting the drive signal of the DC-DC circuit switching transistors at the energy transfer transmitter. Furthermore, it achieves stable load output voltage regulation and wide-range adjustment of the system voltage gain by adjusting the switching frequency and phase shift angle of the full-bridge inverter circuit. Finally, stability and simulation experiments are used to verify and observe the effectiveness of this method.

[0105] Simulation results are displayed in Figure 6 , Figure 7 middle, Figure 6 Figure (a) presents the response diagram of DC input voltage and load output voltage under single hybrid control. When the ideal output voltage is 100 volts, and the DC input voltage experiences a step impulse at 25 milliseconds, the load output voltage first slowly rises to the ideal value before the step point. At the step point, there is a large overshoot value. After reaching the overshoot peak, it slowly decreases to and remains at the ideal value. Meanwhile, Figure 6 Figure (b) shows the DC input voltage and load output voltage response under dual hybrid control. Under dual hybrid control, the load output voltage spikes before the step point, then slowly rises to 100 volts. A significant overshoot also exists at the step point. After reaching the overshoot peak, the voltage oscillates and decreases to and remains at the ideal value. Compared to the no-control method, the dynamic wireless charging system under single hybrid control and the dynamic wireless charging system under dual hybrid control exhibit general constant voltage regulation performance, but with higher overshoot and longer settling time. Furthermore, the overshoot under single hybrid control is slightly higher than that under dual hybrid control. Figure 6 (c) shows the DC input voltage and load output voltage response when the LADRC controller is combined with single hybrid control. The settling time of the load output voltage before the step point is shorter than that of the single hybrid control. At the same time, there is a very small fluctuation after the step point (which can be ignored), and then it drops rapidly to and remains at the ideal value. Figure 6Figure (d) shows the DC input voltage and load output voltage response when the LADRC controller is combined with dual hybrid control. The load output voltage spikes before the step point, then slowly rises to 100 volts, but then oscillates until the step point, where there is also a slightly large overshoot. After reaching the overshoot peak, it oscillates down and remains at the ideal value, with a shorter settling time than the single dual hybrid control method. Compared with traditional PI control (single phase-shift control, single frequency conversion control, hybrid control), the LADRC controller combined with a single hybrid controller has the best system output voltage control performance, while the single hybrid control and dual hybrid control methods have poorer system output voltage control performance.

[0106] Figure 7 (a) and Figure 7 Figure (b) shows the effect of system voltage gain under single-hybrid control and dual-hybrid control, respectively. It can be observed that under hybrid control, the system voltage gain can be controlled in both ranges greater than 1 and less than 1, exhibiting a wide adjustment range. Figure 7 (c) and Figure 7 Figure (d) presents the LADRC controller combined with single-hybrid control and dual-hybrid control, respectively. It can be observed that the voltage gain fluctuation after the step transition point is lower than that of the single-hybrid control and dual-hybrid control methods. These simulation results strongly support the performance effectiveness and stability of the present invention, further demonstrating the application potential of the proposed LADRC controller combined with a single-hybrid controller in dynamic wireless charging systems for electric vehicles.

[0107] 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 method for controlling the output voltage of a dynamic wireless charging system for electric vehicles, characterized in that, include: A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply in the dynamic wireless charging system for electric vehicles. The dynamic wireless charging system for electric vehicles is connected to the power grid. The LADRC controller controls the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit. The first single hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage; The DC-DC circuit is a Boost converter chopper circuit. The LADRC controller includes a linear extended state observer and a linear state feedback control law. The linear state feedback control law uses the full-bridge inverter circuit input voltage reference value... and the input voltage of the full-bridge inverter circuit output by the linear expansion state observer The estimated value The difference is used as the feedback control quantity and the first control quantity is output. ; Based on the estimated value of the total disturbance f output by the linear extended state observer For the first control quantity After disturbance compensation, the second control quantity u is obtained. Based on the second control quantity u, the PWM drive signal of the switching transistor in the DC-DC circuit is generated and the DC-DC circuit is controlled. The linear expansion state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage of the full-bridge inverter circuit. Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage of the full-bridge inverter circuit. The estimated value The estimated value of the total disturbance f The formula is as follows: in, Input voltage of the full-bridge inverter circuit The estimated value The differential, The estimated value of the total disturbance f The differential; These are the two control coefficients of the linearly extended state observer.

2. The method for controlling the output voltage of a dynamic wireless charging system for electric vehicles according to claim 1, characterized in that, The estimated value of the total disturbance f based on the output of the linearly extended state observer. For the first control quantity After disturbance compensation, the second control variable u is obtained, which satisfies the following formula: 。 3. The method for controlling the output voltage of a dynamic wireless charging system for electric vehicles according to claim 1, characterized in that, The first single-hybrid controller performs frequency conversion and phase shift control on the full-bridge inverter circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically including: First, calculate the voltage error between the actual output voltage of the system and the given output voltage. Then the first PI controller adjusts the voltage error. The phase shift angle D is calculated; then, the switching frequency is calculated based on the voltage error c and the phase shift angle D. Based on the phase shift angle D and the switching frequency The corresponding PWM drive signal for the switching transistor is generated to stabilize the output voltage of the control system.

4. The method for controlling the output voltage of a dynamic wireless charging system for electric vehicles according to claim 1, characterized in that, The control method further includes: The four diodes and capacitors in parallel in the rectifier circuit of the wireless charging system are replaced with four controllable MOSFET switches. A second single hybrid controller is used to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit according to the system output voltage, thereby stabilizing the system output voltage.

5. The method for controlling the output voltage of a dynamic wireless charging system for electric vehicles according to claim 4, characterized in that, The method of using a second single-hybrid controller to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit based on the system output voltage, thereby stabilizing the system output voltage, specifically includes: First, calculate the voltage error between the actual output voltage of the system and the given output voltage. Then the second PI controller adjusts the voltage error. The phase shift angle D is calculated; then, based on the voltage error... The switching frequency is obtained by calculating the phase shift angle D. Based on the phase shift angle D and the switching frequency The corresponding PWM drive signal for the switching transistor is generated to stabilize the output voltage of the control system.

6. An output voltage control device for a dynamic wireless charging system for electric vehicles, characterized in that, include: A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply of the dynamic wireless charging system for electric vehicles, and the dynamic wireless charging system for electric vehicles is connected to the power grid. The DC-DC circuit is a Boost converter chopper circuit. The LADRC controller is used to control the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit. The LADRC controller includes a linear extended state observer and a linear state feedback control law. The linear state feedback control law uses the full-bridge inverter circuit input voltage reference value... and the input voltage of the full-bridge inverter circuit output by the linear expansion state observer The estimated value The difference is used as the feedback control quantity and the first control quantity is output. ; Based on the estimated value of the total disturbance f output by the linear extended state observer For the first control quantity After disturbance compensation, the second control quantity u is obtained. Based on the second control quantity u, the PWM drive signal of the switching transistor in the DC-DC circuit is generated and the DC-DC circuit is controlled. The linear expansion state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage of the full-bridge inverter circuit. Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage of the full-bridge inverter circuit. The estimated value The estimated value of the total disturbance f The formula is as follows: in, Input voltage of the full-bridge inverter circuit The estimated value The differential, The estimated value of the total disturbance f The differential; These are the two control coefficients for the linearly extended state observer; The first single hybrid controller is used to perform frequency conversion and phase shift control on the full-bridge inverter circuit according to the system output voltage, thereby stabilizing the system output voltage.

7. An output voltage control device for a dynamic wireless charging system for electric vehicles, characterized in that, include: A DC-DC circuit is added between the full-bridge inverter circuit and the DC power supply in the dynamic wireless charging system for electric vehicles, and the dynamic wireless charging system for electric vehicles is connected to the power grid; and the four diodes and capacitors in parallel in the rectifier circuit of the wireless charging system are replaced with four controllable MOSFET switches. The DC-DC circuit is a Boost converter chopper circuit. The LADRC controller is used to control the DC-DC circuit according to the system input voltage, thereby stabilizing the input voltage of the full-bridge inverter circuit. The LADRC controller includes a linear extended state observer and a linear state feedback control law. The linear state feedback control law uses the full-bridge inverter circuit input voltage reference value... and the input voltage of the full-bridge inverter circuit output by the linear expansion state observer The estimated value The difference is used as the feedback control quantity and the first control quantity is output. ; Based on the estimated value of the total disturbance f output by the linear extended state observer For the first control quantity After disturbance compensation, the second control quantity u is obtained. Based on the second control quantity u, the PWM drive signal of the switching transistor in the DC-DC circuit is generated and the DC-DC circuit is controlled. The linear expansion state observer uses the product of the second control quantity u and the control gain b of the full-bridge inverter circuit, and the actual input voltage of the full-bridge inverter circuit. Estimate the system state of the DC-DC circuit and observe disturbances, thereby outputting the input voltage of the full-bridge inverter circuit. The estimated value The estimated value of the total disturbance f The formula is as follows: in, Input voltage of the full-bridge inverter circuit The estimated value The differential, The estimated value of the total disturbance f The differential; These are the two control coefficients for the linearly extended state observer; The second single hybrid controller is used to perform frequency conversion and phase shift control on the four controllable MOSFET switches of the rectifier circuit according to the system output voltage, thereby stabilizing the system output voltage.

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