WPT system efficient constant-current/constant-voltage charging method based on variable inductor

Abstract

The invention discloses a WPT system efficient constant-current / constant-voltage charging method based on a variable inductor, and belongs to the technical field of wireless charging. The problems that in the prior art, when a WPT system adopts a full-bridge phase shift control technology to achieve wide-load-range and wide-coupling-coefficient constant-current / constant-voltage power supply, the inverter loss is large, and the system efficiency is low are solved. The method comprises the following steps: a, establishing a fundamental wave equivalent model of a double-half-bridge inverter WPT system based on variable inductance; b, calculating the operation range of the variable inductor under the constant current / constant voltage output condition; c, establishing a variable inductor magnetic circuit equivalent model, and designing a variable inductor according to a variable inductor operation range; and d, designing a constant-current / constant-voltage output closed-loop control strategy of the system. According to the method, the conduction loss, the switching loss and the circulating current loss of the inverter are effectively reduced, so that the system always works in a high-efficiency state, the control is simple, the continuous and rapid adjustment of the working state of the system can be realized, and the dynamic performance is good.

Description

technical field [0001] The present invention relates to the technical field of wireless charging, in particular to a high-efficiency constant-current / constant-voltage charging method for WPT systems based on variable inductance. in an efficient state. Background technique [0002] Wireless Power Transfer (WPT) technology uses energy carriers in space (such as electric fields, magnetic fields, microwaves, electromagnetic waves, etc.) to transfer electric energy from the power supply side to the load side. Among them, the inductive WPT technology, as a safe and reliable non-contact power supply technology, can solve many defects of traditional wired power transmission equipment, avoid the safety problems of contact sparks and leakage in the traditional plugging system, and make human use The way of electric energy is more flexible. At present, this technology has been widely used in human implanted medical equipment, induction heaters, electric vehicles and wireless charging...

AI Technical Summary

Problems solved by technology

However, with this method, it is difficult to achieve soft switching of the inverter, especially under light load conditions, resulting in increased switching losses of the inverter; in addition, the traditional full-bridge high-frequency inverter is operated by Two high-frequency switches are connected in series to pass the transmitting coil current. When the current value is large, the conduction loss of the inverter will increase exponentially.

As a result, the total losses of the inverter increase and the system efficiency decreases significantly

Images