High-precision foreign object detection system and method in wireless power transmission system

Abstract

The present invention provides a high-precision foreign matter detection system and method in a wireless electric energy transmission system. The method comprises the steps of: generating voltage signals through a balance coil; accessing the voltage signals into a signal collection circuit by a resonance circuit in a differential mode; processing the voltage signals and obtaining target signals bythe signal collection circuit; converting the target signals to initial direct current signals by a rectification filtering circuit; performing amplification and voltage compensation for the initialdirect current signals through an amplification circuit and a voltage compensation circuit to obtain an output voltage; performing sampling for the output voltage by an AD sampling circuit, and transmitting a sampling result to a controller; and extracting and outputting feature parameters of the voltage signals by the controller to determine whether there are foreign matters or not. The high-precision foreign matter detection system and method in the wireless electric energy transmission system take the transmitting coil as excitation of the detection coil with no need for extra excitation circuits to reduce the cost, employ a circuit structure with rectification and then amplification to improve the detection precision of the foreign matters and employ a voltage compensation circuit structure to solve the problem of saturation of the output voltage and achieve effective identification for small metal foreign matters, and the system structure is simple.

Description

technical field [0001] The invention relates to the technical fields of circuit design and magnetic circuit design, and belongs to the field of foreign object detection in wireless charging systems, and in particular, relates to a high-precision foreign object detection system and method in a wireless power transmission system. Background technique [0002] Global warming and air pollution have become the focus of world attention, and vehicles with internal combustion engines at their core are the main cause of the problem. In order to promote a green and environmentally friendly lifestyle, electric vehicles have emerged as the times require. Electric vehicles are driven by electric motors, which drive the wheels forward by converting electrical energy into mechanical energy, and have extremely high energy utilization efficiency. Electric vehicles can almost meet the requirements of "zero emission" and "zero pollution" while ensuring the performance of the original vehicle....

AI Technical Summary

Problems solved by technology

From domestic and foreign perspectives, the existing metal detection methods are difficult to meet the safety and cost requirements of automotive wireless charging

Images