Wireless power transmission system and load switching control method thereof

Abstract

The invention discloses a wireless power transmission system and a load switching control method thereof. An MCU at a receiving end collects the output voltage of a rectifier and filter circuit at the receiving end in real time, judges whether the load is switched and in which direction the load is switched in real time based on the change amplitude of the output voltage, and adjusts the working frequency of the system quickly to a new resonant working frequency according to the judgment result to make the system quickly recovered to a new resonant state, so that voltage leap after rectification is inhibited, and the system can be quickly stabilized again. Excess voltage fluctuation after rectification due to load change at the wireless receiving end is prevented effectively, and the working stability of the wireless power transmission system is improved.

Description

technical field [0001] The invention belongs to the field of wireless power transmission, and in particular relates to a load switching control method in a wireless power transmission system. Background technique [0002] In recent years, wireless charging technology has developed rapidly. Because of its non-contact, wire-free connection, and convenient operation, it has attracted much attention, and various wireless charging products have also come out one after another. As its wireless charging technology matures and its application fields become more and more extensive, power improvement and better user experience are becoming more and more important. [0003] The existing wireless charging system, as a whole, includes two parts: the wireless energy transmitter and the wireless energy receiver, and the wireless energy transmitter and the wireless energy receiver transmit energy through a magnetic field, and there is no wire connection between the two. To obtain the statu...

AI Technical Summary

Problems solved by technology

If the output voltage drop at the receiving end is too large, in severe cases, the receiving end system can be in a short-term power-off state, so that the system can work in an uncontrollable abnormal state

In the same way, when the load is switched from heavy load to light load, the temporary detuning of the system will also cause the output voltage of the receiving end to be too high after rectification, which is very easy to burn the voltage regulator circuit of the subsequent stage, or increase the voltage of the subsequent stage circuit. The input voltage stress

To sum up, the receiving end of the wireless power transfer system obtains energy from the electromagnetic field, not a stable constant current source or constant voltage source, and is easily affected by changes in load and the like.

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