CN-122001064-A - Wireless charging ground terminal anti-saturation PID control method and system

Abstract

The invention relates to the technical field of wireless charging and discloses a wireless charging ground anti-saturation PID control method and a system, wherein the wireless charging ground anti-saturation PID control method comprises the following steps of S1, acquiring a voltage error value Verr of the system in a current control period; S2, if the absolute value of the voltage error value Verr is larger than a first threshold Vth and smaller than or equal to a second threshold Voff, entering S3, otherwise, entering S4, wherein the second threshold Voff is larger than the first threshold Vth, S3, maintaining the output value of a controller of a current control period as the output value of a controller of a previous control period, stopping updating an integral control item, S4, updating the output value of the current control period based on the voltage error value Verr, and executing proportional integral PI control operation to update the output value of the controller of the current control period.

Inventors

• Guan Hongji
• CHEN JIANBIN
• Luo Xianghao
• YANG CHENGYU
• ZHANG CHENGDONG
• TAN HAOJIE
• ZOU JIANJUN

Assignees

• 广东泰坦智能动力有限公司

Dates

Publication Date

20260508

Application Date

20260408

Claims (7)

1. 1. The anti-saturation PID control method for the wireless charging ground terminal is characterized by comprising the following steps of: s1, acquiring a voltage error value Verr of a system in a current control period; s2, if the absolute value of the voltage error value Verr is larger than a first threshold Vth and smaller than or equal to a second threshold Voff, entering S3, otherwise, entering S4, wherein the second threshold Voff is larger than the first threshold Vth; S3, maintaining the output value of the controller in the current control period as the output value of the controller in the previous control period, and stopping updating the integral control item; and S4, updating the control output value of the current control period based on the voltage error value Verr, and executing proportional-integral PI control operation to update the controller output value of the current control period.
2. 2. The wireless charging ground-side anti-saturation PID control method according to claim 1, wherein S2 comprises the steps of: s2.1, in a microprocessor of the system, calculating a first state identifier and a second state identifier based on the voltage error value; S2.2, reading the first state identifier and the second state identifier in an interrupt service routine of the system or a control law accelerator independent of the microprocessor, and performing logical AND operation on the first state identifier and the second state identifier; In S2.1, the first state flag is used to identify whether the absolute value of the voltage error value Verr is greater than the first threshold value, and the second state flag is used to identify whether the absolute value of the voltage error value Verr is less than or equal to the second threshold value.
3. 3. The method of claim 2, wherein the steps of calculating the first state identifier and the second state identifier in S2.1 and obtaining the voltage error value in S1 are all completed in the same period.
4. 4. A method of anti-saturation PID control of a wireless charging ground according to claim 3, characterized in that in S2.2, it is performed in a control law accelerator task triggered by a timer interrupt, which control law accelerator shares memory with the microprocessor to exchange the first state identification, the second state identification and the control output value.
5. 5. The wireless charging ground-side anti-saturation PID control method according to claim 1, wherein S1 comprises the steps of: s1.1, acquiring output voltage of a secondary side of a wireless charging system to obtain an actual output voltage value; S1.2, obtaining a voltage error value Verr according to the following formula; Verr=Vref-Vfb; Wherein Vref is the reference value of the output voltage, and Vfb is the actual value of the output voltage.
6. 6. A wireless charging system applying the wireless charging ground anti-saturation PID control method according to any one of claims 1-5, wherein the system comprises a primary side resonant cavity assembly, a primary side inverter connected with the primary side resonant cavity assembly, a secondary side resonant cavity assembly and a secondary side receiver connected with the secondary side resonant cavity, and the primary side resonant cavity assembly and the secondary side resonant cavity assembly are mutually inductive.
7. 7. The wireless charging system of claim 6, wherein the primary inverter is a phase-shifted full-bridge circuit, and the controller output value is a phase-shifted angle of the phase-shifted full-bridge.

Description

Wireless charging ground terminal anti-saturation PID control method and system Technical Field The invention relates to the technical field of wireless charging, in particular to an anti-saturation PID control method and system for a wireless charging ground terminal. Background The anti-integral saturation method (such as integral amplitude limiting, conditional integral, reverse calculation and the like) commonly used in the industrial control at present has obvious inadaptability in a wireless charging system with centralized control at the ground terminal although the method has good effect in a local closed loop system (such as motor drive and DC-DC power supply), and mainly comprises the following aspects: 1. Error distortion due to communication delay is ignored. These methods default to error signals in real time, but the voltage/current feedback received at the ground in wireless charging often lags behind by tens of milliseconds. The integral term is updated by the lag error, and even if clipping is performed, the integral term is possibly accumulated towards the wrong direction and still saturated after long-time operation, and 2, blind adjustment is still performed in the steady state. Even if the system has stabilized around the target value, the conventional PI will still continuously fine tune the output according to the delay error. The adjustment can not improve the precision, but can cause the output to shake around a steady-state point to influence the charging stability due to the 'over-time correction', and 3, the adjustment has no coping capability for long-term drift. In these wireless charging systems for AGVs and industrial robots, the single charging time is typically only a few tens of minutes to an hour, but the output current is gradually reduced during the constant voltage phase of the charging process (especially near full charge), the error signal amplitude is weak and changes slowly. At this stage, if the controller continues to perform PI adjustment based on feedback with communication delay, even if the sensor zero drift, communication error code or load small fluctuation only introduces a small unidirectional residual, the integral term may continue to accumulate and approach the clipping boundary for tens of minutes. Once slight disturbance (such as vehicle position deviation or contact impedance change) occurs in the charging process, the saturated integral term can cause obvious overshoot when the regulation is restored, so that the charging precision and the system stability are affected, and the dynamic and the steady state are difficult to be compatible. Some schemes (such as back calculation) rely on output saturation to trigger integral correction, but the output is not saturated under normal working conditions, so that a correction mechanism is invalid, and excessive integral inhibition can weaken the response speed of a system to real disturbance (such as coil offset), and 5, the steady state holding capacity of the system is not utilized. The resonant cavity (LCC-SS or LCC-LCC) with resonant wireless charging has a certain self-sustaining characteristic near a steady-state working point, the control quantity is unchanged for a short time, and the output can still be kept stable. However, the existing PI controller cannot actively pause, but continuously operate and adjust, so that the burden of the controller is increased, unnecessary control noise is introduced, and 6, the existing scheme is to remedy after the problem of the integral term is solved, and invalid integral is actively avoided under the unreliable feedback condition. Such a passive strategy is clearly inadequate for industrial wireless charging systems that emphasize long-term reliability and steady-state accuracy. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a wireless charging ground-end anti-saturation PID control method and system. The invention discloses a wireless charging ground terminal anti-saturation PID control method, which comprises the following steps: s1, acquiring a voltage error value Verr of a system in a current control period; s2, if the absolute value of the voltage error value Verr is larger than a first threshold Vth and smaller than or equal to a second threshold Voff, entering S3, otherwise, entering S4, wherein the second threshold Voff is larger than the first threshold Vth; S3, maintaining the output value of the controller in the current control period as the output value of the controller in the previous control period, and stopping updating the integral control item; and S4, updating the control output value of the current control period based on the voltage error value Verr, and executing proportional-integral PI control operation to update the controller output value of the current control period. According to the scheme, judgment logic is converted into efficient Boolean operation. The logic essentially consists