Control method for dynamic wireless charging system of electric vehicle

Abstract

A control method of a dynamic wireless charging system of an electric automobile comprises the steps that current state information of the automobile is obtained in real time, and the current state information comprises the center position, the speed, the yaw angle and the front wheel rotation angle of the automobile; on the basis of the vehicle kinematics model and the dynamics model, position coordinates of the vehicle at future moments are predicted in real time; according to the installation offset of the receiving coil and the center of the vehicle, the predicted position of the vehicle is converted into the predicted position of the vehicle-mounted receiving coil and sent to a ground end controller; the receiving coil predicted position is matched with the segmented guide rail coordinates in real time, the coil activation advance is dynamically calculated by combining the vehicle speed, and it is ensured that electric energy transmission is synchronous with the vehicle position. According to the method, the vehicle kinematics and dynamics models are introduced to predict the position of the vehicle-mounted coil, an additional position detection sensor or coil does not need to be added, and the construction cost is reduced. Meanwhile, the starting lead of the ground transmitting coil is calculated by combining the vehicle speed, the accuracy of guide rail switching control is improved, and the waste of electric energy is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, and particularly relates to a control method for an electric vehicle dynamic wireless charging system. Background Technique

[0002] With the rapid development of electric vehicles, dynamic wireless charging technology has attracted much attention due to its advantage of "charging while driving". Electric vehicle dynamic wireless charging is based on short-segment guide rail magnetic coupling resonance technology, which realizes power transmission during vehicle driving by burying transmitting coils in segments under the road. Since it takes a certain time to establish the electromagnetic field, when the vehicle is detected and power supply is started, the vehicle may have passed the optimal charging position, resulting in waste of the energy transmission window. Therefore, the switching control of the guide rail affects the overall transmission efficiency and energy utilization rate of the system.

[0003] In order to achieve the position detection of the on-vehicle receiving coil to control the switching of the segmented guide rail, the prior art performs the position detection of the receiving coil by adding a position detection sensor or coil and then controls the switching of the ground-side segmented guide rail coil. With the increase in the mileage of the wireless charging section, the usage amount of sensors or detection coils also increases greatly. This method has the disadvantages of a large number of component usages and high system costs. Moreover, due to the existence of the magnetic field establishment time and system delay time, the switching efficiency of the transmitting coil decreases, resulting in reduced energy utilization rate. Summary of the Invention

[0004] Aiming at the above technical problems, the present technical solution provides a control method for an electric vehicle dynamic wireless charging system, providing a guide rail switching control strategy to achieve precise switching of the ground transmitting end segmented guide rail during the dynamic wireless charging process, enabling efficient switching of the ground segmented guide rail, further improving the energy utilization rate; the on-vehicle receiving coil position detection method avoids the use of too many position detection sensors or coils, and realizes the position detection of the electric vehicle on-vehicle receiving coil without additionally adding detection coils or sensors, greatly reducing the implementation cost; it can effectively solve the above problems.

[0005] The present invention is realized through the following technical solutions:

[0006] A control method for an electric vehicle dynamic wireless charging system includes the steps of:

[0007] Step 1: Real-time obtain the current state information of the vehicle, including the vehicle center position, speed, yaw angle, and front wheel steering angle;

[0008] Step 2: Based on the vehicle kinematic model and dynamic model, real-time predict the position coordinates of the vehicle at a future moment;

[0009] The state equation of the vehicle kinematic model satisfies:

[0010]

[0011] wherein, are respectively the x-axis and y-axis coordinates at the center of the vehicle's rear axle; θ is the angle between the X-axis of the inertial coordinate system and the x-axis of the vehicle body coordinate system; ω L is the yaw angular velocity of the vehicle; δ f is the steering angle of the vehicle's front wheels; c is the wheelbase between the front and rear axles of the vehicle; v car is the speed at the center of the vehicle's rear axle;

[0012] The state of the dynamic model considers the tire force condition, and its equation satisfies:

[0013]

[0014] wherein, m is the vehicle body weight, v ya is the lateral acceleration of the vehicle, v x is the longitudinal speed of the vehicle, ω L is the yaw angular velocity of the vehicle, C cf is the cornering stiffness of the vehicle's front-wheel tires, δ f is the steering angle of the vehicle's front wheels, v y is the lateral speed of the vehicle, L1 is the distance from the front axle to the vehicle's center of mass, C cr is the cornering stiffness of the vehicle's rear-wheel tires, L2 is the distance from the rear axle to the vehicle's center of mass; v xa is the longitudinal acceleration of the vehicle; I z is the moment of inertia of the vehicle about the z-axis, θ a is the yaw angular acceleration of the vehicle; Y vehicle is the vehicle's ordinate in the inertial coordinate system, X vehicle is the vehicle's abscissa in the inertial coordinate system;

[0015] Step 3: Convert the predicted vehicle position to the predicted position of the on-vehicle receiving coil according to the installation offset between the on-vehicle receiving coil and the vehicle center;

[0016] Step 4: Send the predicted position coordinates of the receiving coil to the ground controller through the on-vehicle GPS module;

[0017] Step 5: The ground controller maps the predicted position coordinates of the received on-vehicle coil to the segmented guideway coordinate system and determines the ground transmitting coil number;

[0018] Step 6: Calculate the advance activation time of the transmitting coil and trigger the control signal according to the vehicle speed and system delay.

[0019] Furthermore, for the vehicle kinematic and dynamic model, the discretization equations of its state variables and output variables satisfy:

[0020]

[0021] Among them, A d , B d , C d are the system model coefficient matrices; ζ(k) is the state variable at time k, ζ(k + 1) is the predicted state variable at time k + 1, u(k) is the control input at time k, and λ(k) is the output variable at time k;

[0022] The prediction equations of the state variables and output variables after discretization of the vehicle kinematic and dynamic models satisfy:

[0023]

[0024] Among them, P is the prediction step; ζ(k + P|k) represents the predicted value of the state variable at time k + P predicted at time k; λ(k + P|k) represents the predicted value of the output variable at time k + P predicted at time k; ζ(k|k) represents the state variable at time k; A d P , A d P-1 , A d 0 respectively represent the P-th, (P - 1)-th, and 0-th powers of the coefficient matrix A d ; u(k|k) represents the value of the control output at time k; u(k + P - 1|k) represents the value of the control input at time k + P - 1.

[0025] Furthermore, the installation offset of the on-vehicle receiving coil described in Step 3 is a fixed value for the installation offset (Δx, Δy, Δz) in the vehicle body coordinate system, and this value is obtained through measurement; the predicted position (X P-coil , Y P-coil , Z P-coil ) of the on-vehicle receiving coil is equal to the predicted position (X P-vehicle , Y P-vehicle , Z P-vehicle ) of the vehicle center plus the corresponding offset, satisfying the following formula:

[0026]

[0027] Among them, Δx is the distance between the center point of the receiving coil and the center point of the vehicle in the x-axis direction in the vehicle coordinate system, Δy is the distance between the center point of the receiving coil and the center point of the vehicle in the y-axis direction in the vehicle coordinate system, and Δz is the distance between the center point of the receiving coil and the center point of the vehicle in the z-axis direction in the vehicle coordinate system.

[0028] Further, the division rule of the segmented guide rail coordinate system described in Step 5 is as follows: Each transmitting coil corresponds to a rectangular area. In the vehicle forward direction, the opening and closing boundary coordinates of the first transmitting coil are defined as (a, b) and (a + L, b) respectively, with the number 1; Due to a certain interval between the transmitting coils, the opening and closing boundary coordinates of the second transmitting coil are defined as (a + L + i, b) and (a + 2L + i, b), with the number 2; The opening and closing boundary coordinates of the third transmitting coil are defined as (a + 2L + 2i, b) and (a + 3L + 2i, b), with the number 3; And so on, the boundary coordinates of the nth transmitting coil are defined as (a + (n - 1)(L + i), b) and (a + nL + (n - 1)i, b), with the number n; where a and b are the horizontal and vertical coordinates of the starting position of the segmented guide rail transmitting coil; L is the length of the transmitting coil; i is the distance between the transmitting coils; The opening and closing boundary coordinates of the segmented guide rail transmitting coil after division and the transmitting coil number are stored in the ground end controller.

[0029] Further, the specific operation method of Step 5 is as follows: When the ground end controller receives the predicted position of the vehicle-mounted receiving coil from the GPS module, it maps it to the segmented guide rail coordinate system of the controller; When the distance between the predicted position coordinate of the vehicle-mounted receiving coil and the opening boundary coordinate of the ground transmitting coil is less than or equal to the magnetic field establishment distance D, it is determined that the transmitting coil with this number is the target opening coil; When the distance between the predicted position coordinate of the vehicle-mounted receiving coil and the closing boundary coordinate of the ground transmitting coil is greater than or equal to the magnetic field detachment distance d, it is determined that the transmitting coil with this number is the target closing coil.

[0030] Further, the advance activation time T of the transmitting coil described in Step 6 needs to satisfy:

[0031]

[0032] where s is the distance between the predicted vehicle position and the magnetic field establishment distance D; v is the current vehicle speed, and t d is the time from when the control signal is sent until the receiving coil reaches the rated output power, including the power device response delay and the magnetic field establishment time.

[0033] Further, the trigger moment T of the control signal described in Step 6 trigger needs to satisfy:

[0034] T trigger = T now + T - T margin ;

[0035] where T now is the current moment, T is the calculated advance activation time, and T margin is the safety margin time.

[0036] Beneficial effects

[0037] A control method for a dynamic wireless charging system of an electric vehicle proposed by the present invention, compared with the prior art, has the following beneficial effects:

[0038] (1) Through the segmented guide rail coordinate system, the present invention realizes the switching control of the segmented guide rail coils at the ground end. By means of the sensors on the vehicle itself, initial information including the vehicle position, speed, yaw angle, and front wheel steering angle is obtained, and the position prediction of the on-vehicle receiving coil is realized based on the vehicle kinematics and dynamics models; compared with the prior art, the usage amount of position detection sensors or coils is greatly reduced, and it has higher economy while ensuring performance, and the system implementation cost is lower. In addition, based on the position prediction of the on-vehicle receiving coil, by activating the transmitting coil in advance, it is ensured that the magnetic field is fully established when the vehicle arrives, maximizing the effective charging time window, significantly improving the energy transmission efficiency, and reducing system losses. Description of the drawings

[0039] Figure 1 is a schematic diagram of a segmented guide rail electric vehicle dynamic wireless charging system in the present invention.

[0040] Figure 2 is a schematic diagram of the overall process of the present invention.

[0041] Figure 3 is a schematic diagram of the coordinate division of the ground end transmitting coil and the control of the coil in the present invention. Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Without departing from the design concept of the present invention, various modifications and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope of the present invention.

[0043] Embodiment 1:

[0044] A control method for a dynamic wireless charging system of an electric vehicle, as Figure 1 shown, the electric vehicle moves and charges along the x-axis with segmented transmitting coils laid; in order to ensure that the electric vehicle can always receive electrical energy from the energized coil below during the movement, the precise switching of the coil is crucial during the dynamic wireless charging of the electric vehicle. The specific control method is as Figure 2 shown, including the steps:

[0045] Step 1: Real-time obtain the current state information of the vehicle, including the vehicle center position, speed, yaw angle, and front wheel steering angle.

[0046] Step 2: Based on the vehicle kinematic model and dynamic model, real-time predict the position coordinates of the vehicle at future moments.

[0047] Establish a vehicle kinematic model, whose state equation satisfies:

[0048]

[0049] Wherein, are respectively the x-axis and y-axis coordinates at the center of the rear axle of the vehicle; θ is the angle between the X-axis of the inertial coordinate system and the x-axis of the vehicle body coordinate system; ω L is the yaw angular velocity of the vehicle; δ f is the front wheel steering angle of the vehicle; c is the wheelbase between the front and rear axles of the vehicle; v car is the speed at the center of the rear axle of the vehicle.

[0050] The state of the dynamic model considers the tire force condition, and its equation satisfies:

[0051]

[0052] Wherein, m is the vehicle body weight, v ya is the lateral acceleration of the vehicle, v x is the longitudinal speed of the vehicle, ω L is the yaw angular velocity of the vehicle, C cf is the cornering stiffness of the front wheel tire of the vehicle, δ f is the deflection angle of the front wheel of the vehicle, v y is the lateral speed of the vehicle, L1 is the distance from the front axle to the vehicle center of mass, C cr is the cornering stiffness of the rear wheel tire of the vehicle, L2 is the distance from the rear axle to the vehicle center of mass; v xa is the longitudinal acceleration of the vehicle; I z is the moment of inertia of the vehicle about the z-axis, θ a is the yaw angular acceleration of the vehicle; Y vehicle is the vehicle ordinate in the inertial coordinate system, X vehicle is the vehicle abscissa in the inertial coordinate system.

[0053] Discretize the vehicle kinematic and dynamic models. The discretized state space equations of the state variables and output variables satisfy:

[0054]

[0055] Wherein, A d 、B d 、C d are the system model coefficient matrices; ζ(k) is the state variable at time k, ζ(k + 1) is the predicted state variable at time k + 1, u(k) is the control input variable at time k, and λ(k) is the output variable at time.

[0056] The state variables and output variable prediction equations after discretization of the vehicle kinematic and dynamic models satisfy:

[0057]

[0058] Among them, P is the prediction step; ζ(k+P|k) represents the predicted value of the state variable predicting k+P at time k; λ(k+P|k) represents the predicted value of the output variable predicting k+P at time k; ζ(k|k) represents the state variable at time k; A d P 、A d P-1 、A d 0 respectively represent the Pth, (P-1)th, and 0th powers of the coefficient matrix A d ; u(k|k) represents the value of the control output at time k; u(k+P-1|k) represents the value of the control input at time k+P-1.

[0059] Step 3: Convert the predicted vehicle position to the predicted position of the on-vehicle receiving coil according to the installation offset between the on-vehicle receiving coil and the vehicle center.

[0060] The state variable information of the vehicle at the current time k is obtained in real time through the vehicle's own sensors, including the vehicle center position, speed, yaw angle, and front wheel steering angle. Taking the vehicle speed and front wheel angle as the control input, and the vehicle center position as the output, the predicted position of the vehicle center is obtained through the vehicle kinematic and dynamic prediction equations.

[0061] Since there is an installation deviation between the position coordinates of the on-vehicle receiving coil and the vehicle coordinates. Therefore, the predicted position of the vehicle center cannot be directly used as a reference for turning on and off the ground transmitting coil, and the predicted position coordinates of the vehicle center need to be converted into the predicted position coordinates of the on-vehicle receiving coil center. The specific conversion method is as follows:

[0062] The predicted position (X P-coil , Y P-coil , Z P-coil ) of the on-vehicle receiving coil is equal to the predicted position (X P-vehicle , Y P-vehicle , Z P-vehicle ) of the vehicle center plus the corresponding offset, satisfying the following formula:

[0063]

[0064] Among them, Δx is the distance between the center point of the receiving coil and the center point of the vehicle in the x-axis direction in the vehicle coordinate system, Δy is the distance between the center point of the receiving coil and the center point of the vehicle in the y-axis direction in the vehicle coordinate system, and Δz is the distance between the center point of the receiving coil and the center point of the vehicle in the z-axis direction in the vehicle coordinate system.

[0065] The installation offset (Δx, Δy, Δz) in the vehicle body coordinate system is a fixed value, which is obtained through measurement. Based on this, the predicted position of the vehicle-mounted receiving coil can be obtained. During specific implementation, it is necessary to divide the boundary coordinates of the ground segmented guide rail coil in advance and determine the transmitting coil number, and store them in the controller together. The boundary coordinates of each segmented guide rail coil are respectively defined as the opening and closing coordinates, and the transmitting coil number is defined according to the vehicle traveling direction.

[0066] Step Four: Send the predicted receiving coil position coordinates to the ground controller through the vehicle-mounted GPS module.

[0067] Step Five: The ground controller maps the predicted position coordinates of the vehicle-mounted coil to the segmented guide rail coordinate system and determines the ground transmitting coil number; combined with Figure 3 Divide the boundary coordinates for opening and closing the coil for each rectangular transmitting coil. The division rule of the segmented guide rail coordinate system is:

[0068] Each transmitting coil corresponds to a rectangular area. In the vehicle forward direction, the opening and closing boundary coordinates of the first transmitting coil are defined as (a, b) and (a + L, b) respectively, and the number is 1; due to a certain interval between the transmitting coils, the opening and closing boundary coordinates of the second transmitting coil are defined as (a + L + i, b) and (a + 2L + i, b), and the number is 2; the opening and closing boundary coordinates of the third transmitting coil are defined as (a + 2L + 2i, b) and (a + 3L + 2i, b), and the number is 3; and so on. The boundary coordinates of the nth transmitting coil are defined as (a + (n - 1)(L + i), b) and (a + nL + (n - 1)i, b), and the number is n; where a and b are the horizontal and vertical coordinates of the starting position of the segmented guide rail transmitting coil; L is the length of the transmitting coil; i is the distance between the transmitting coils; store the opening and closing boundary coordinates of the segmented guide rail transmitting coil after division and the transmitting coil number in the ground controller. The ground controller receives the predicted position of the vehicle-mounted receiving coil from the GPS module and calculates the distance between the opening and closing boundary coordinates of the transmitting coil stored in the controller at the same time.

[0069] When the distance between the predicted position coordinates of the receiving coil and the opening boundary coordinates of the transmitting coil is equal to the magnetic field establishment distance D, it is determined that the transmitting coil is the target opening coil. When the distance between the predicted position coordinates of the receiving coil and the closing boundary coordinates of the transmitting coil is equal to the magnetic field detachment distance d, it is determined that the transmitting coil is the closing coil. For example, when the predicted position of the vehicle-mounted receiving coil calculated is equal to D from the opening boundary coordinates of the transmitting coil 1, the transmitting coil 1 is turned on; as the vehicle moves, when the predicted position of the vehicle-mounted receiving coil calculated is equal to d from the closing boundary coordinates of the transmitting coil 1, the transmitting coil 1 is turned off.

[0070] In implementation, the magnetic field establishment distance D and the magnetic field detachment distance d need to be measured in advance. The measurement method is to move the vehicle-mounted receiving coil above the transmitting coil. When the vehicle-mounted receiving coil senses mutual inductance, the magnetic field establishment distance D is obtained. When the mutual inductance of the vehicle-mounted receiving coil disappears, the magnetic field detachment distance d is obtained.

[0071] Step 6: Calculate the early activation time of the transmitting coil according to the vehicle speed and system delay and trigger a control signal.

[0072] Since there is a time delay from when the controller sends out a signal to when the transmitting coil is turned on, activating the transmitting coil when the predicted position of the vehicle-mounted receiving coil is equal to the opening boundary coordinates of the transmitting coil D will result in a lag in power transmission. Therefore, the delay time needs to be considered, and the transmitting coil is activated in advance when the predicted position of the vehicle-mounted receiving coil is greater than D from the opening boundary coordinates of the transmitting coil. The early activation time T of the transmitting coil needs to satisfy:

[0073]

[0074] where s is the distance between the predicted position of the vehicle and the magnetic field establishment distance D; v is the current vehicle speed, and t d is the time from when the control signal is sent out to when the receiving coil reaches the rated output power, including the response delay of the power device and the magnetic field establishment time.

[0075] The triggering moment T of the control signal trigger needs to satisfy:

[0076] T trigger = T now + T - T margin ;

[0077] where T now is the current moment, T is the calculated early activation time, and T margin is the safety margin time.

[0078] The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A control method for a dynamic wireless charging system of an electric vehicle, characterized in that: Including the steps: Step 1: Obtain the current state information of the vehicle in real time, including the vehicle center position, speed, yaw angle, and front wheel steering angle; Step 2: Based on the vehicle kinematic model and dynamic model, predict the position coordinates of the vehicle at a future moment in real time; The state equation of the vehicle kinematic model satisfies: wherein, are respectively the x-axis and y-axis coordinates at the center of the vehicle's rear axle; θ is the angle between the X-axis of the inertial coordinate system and the x-axis of the vehicle body coordinate system; ω L is the yaw angular velocity of the vehicle; δ f is the front wheel steering angle of the vehicle; c is the wheelbase between the front and rear axles of the vehicle; v car is the speed at the center of the vehicle's rear axle; The state of the dynamic model considers the tire force condition, and its equation satisfies: where m is the vehicle body weight, v ya is the lateral acceleration of the vehicle, v x is the longitudinal speed of the vehicle, ω L is the yaw angular velocity of the vehicle, C cf is the cornering stiffness of the front tires of the vehicle, δ f is the steering angle of the front wheels of the vehicle, v y is the lateral speed of the vehicle, L1 is the distance from the front axle to the vehicle's center of mass, C cr is the cornering stiffness of the rear tires of the vehicle, L2 is the distance from the rear axle to the vehicle's center of mass; v xa is the longitudinal acceleration of the vehicle; I z is the moment of inertia of the vehicle about the z-axis, θ a is the yaw angular acceleration of the vehicle; Y vehicle is the vehicle's ordinate in the inertial coordinate system, X vehicle is the vehicle's abscissa in the inertial coordinate system; Step 3: According to the installation offset between the on-vehicle receiving coil and the vehicle center, convert the predicted vehicle position to the predicted position of the on-vehicle receiving coil; Step 4: Send the predicted position coordinates of the receiving coil to the ground controller through the on-vehicle GPS module; Step 5: The ground controller maps the predicted position coordinates of the on-vehicle coil to the segmented guide rail coordinate system and determines the ground transmitting coil number; Step 6: Calculate the early activation time of the transmitting coil according to the vehicle speed and system delay and trigger a control signal.

2. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, wherein: For the vehicle kinematic and dynamic models, the discretization equations of the state variables and output variables satisfy: Among them, A d , B d , C d are the system model coefficient matrices; ζ(k) is the state variable at time k, ζ(k + 1) is the predicted state variable at time k + 1, u(k) is the control input quantity at time k, and λ(k) is the output variable at time The predicted equations of the state variables and output variables after discretization of the vehicle kinematic and dynamic models satisfy: where P is the prediction step; ζ(k+P|k) represents the predicted value of the state variable predicted at time k for k+P; λ(k+P|k) represents the predicted value of the output variable predicted at time k for k+P; ζ(k|k) represents the state variable at time k; A d P and A d P-1 and A d 0 respectively represent the P-th, (P-1)-th, and 0-th powers of the coefficient matrix A d ; u(k|k) represents the value of the control output at time k; u(k+P-1|k) represents the value of the control input at time k+P-1.

3. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, characterized in that: The installation offset between the vehicle-mounted receiving coil described in Step 3 and the vehicle center is a fixed value for the installation offset (Δx, Δy, Δz) in the body coordinate system, and this value is obtained through measurement; the predicted position (X P-coil , Y P-coil , Z P-coil ) of the vehicle-mounted receiving coil is equal to the predicted position (X P-vehicle , Y P-vehicle , Z P-vehicle ) of the vehicle center plus the corresponding offset, satisfying the following formula: Where, Δx is the distance between the center point of the receiving coil and the center point of the vehicle in the x-axis direction in the vehicle coordinate system, Δy is the distance between the center point of the receiving coil and the center point of the vehicle in the y-axis direction in the vehicle coordinate system, and Δz is the distance between the center point of the receiving coil and the center point of the vehicle in the z-axis direction in the vehicle coordinate system.

4. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, characterized in that: The division rule of the segmented guide rail coordinate system in Step 5 is: Each transmitting coil corresponds to a rectangular area. In the vehicle forward direction, define the opening and closing boundary coordinates of the first transmitting coil as (a, b) and (a + L, b) respectively, and the number is 1; Since there is a certain interval between the transmitting coils, define the opening and closing boundary coordinates of the second transmitting coil as (a + L + i, b) and (a + 2L + i, b), and the number is 2; Define the opening and closing boundary coordinates of the third transmitting coil as (a + 2L + 2i, b) and (a + 3L + 2i, b), and the number is 3; And so on, define the boundary coordinates of the nth transmitting coil as (a + (n - 1)(L + i), b) and (a + nL + (n - 1)i, b), and the number is n; Where a and b are the horizontal and vertical coordinates of the starting position of the segmented guide rail transmitting coil; L is the length of the transmitting coil; i is the distance between the transmitting coils; Store the opening and closing boundary coordinates of the segmented guide rail transmitting coil after division and the transmitting coil number in the ground controller.

5. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, characterized in that: The specific operation method of Step 5 is: When the ground controller receives the predicted position of the on-vehicle receiving coil from the GPS module, map it to the segmented guide rail coordinate system of the controller; When the distance between the predicted position coordinates of the on-vehicle receiving coil and the opening boundary coordinates of the ground transmitting coil is less than or equal to the magnetic field establishment distance D, determine that the transmitting coil with this number is the target opening coil; When the distance between the predicted position coordinates of the on-vehicle receiving coil and the closing boundary coordinates of the ground transmitting coil is greater than or equal to the magnetic field detachment distance d, determine that the transmitting coil with this number is the target closing coil.

6. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, characterized in that: The early activation time T of the transmitting coil in Step 6 needs to satisfy: where s is the distance between the predicted position of the vehicle and the magnetic field establishment distance D; v is the current vehicle speed, and t d is the time from the control signal being sent to the receiving coil reaching the rated output power, including the response delay of the power device and the magnetic field establishment time.

7. The control method of a dynamic wireless charging system for an electric vehicle according to claim 1, characterized in that: The triggering moment T of the control signal described in Step 6 trigger shall satisfy: T trigger = T now + T - T margin ; Among them, T now is the current moment, T is the calculated early activation time, T margin is the safety margin time.

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