Soft start method of wireless charging system

Abstract

The invention discloses a soft start system of a wireless charging system. According to the method, the output voltage of an inverter is adjusted by phase shifting. The start process of the system isdivided into three stages. First, the inverter outputs at the maximum phase-shifting angle of 180 degrees before the primary side current reaches a steady-state value thereof so as to realize fast start; second, modulation is started when the primary side current reaches the peak of the steady-state value thereof, and the phase-shifting angle is adjusted to offset primary side induced voltage caused by secondary side current so as to directly enter the steady state; and third, the phase-shifting angle of the inverter is kept unchanged after the secondary side current rises to a steady-state value thereof so as to ensure the constant output voltage. The adoption of the method can effectively enable the primary side current to rise to the steady-state current quickly and then keep unchangedand enable the secondary side to quickly reach the steady state, the consumed time can be reduced to the millisecond level from the second level of the existing method, and the purpose of overcurrentsuppression is achieved in the whole process.

Description

technical field [0001] The invention belongs to the technical field of wireless charging and relates to a soft start method. Background technique [0002] With the popularity of electric vehicles, wireless charging technology is receiving more and more attention due to its advantages of safety, flexibility and convenience. Commonly used electric vehicle wireless charging topologies such as figure 1 As shown, both the primary and secondary sides adopt the SS compensation network structure. During the opening process of the system, due to the existence of the transient process, there may be overvoltage and overcurrent phenomena, such as figure 2 As shown, it will cause hidden danger to the normal operation of the circuit. The traditional approach is to prolong the start-up time as much as possible to achieve soft start. In actual operation, it often takes more than a second, but this is not enough for some occasions that require fast start-up. This paper proposes a fast s...

AI Technical Summary

Problems solved by technology

During the opening process of the system, due to the existence of the transient process, there may be overvoltage and overcurrent phenomena, such as figure 2 As shown, there is a hidden danger to the normal operation of the circuit

The traditional method is to prolong the startup time as much as possible to achieve soft startup. In actual operation, it often takes more than a second. However, this is not enough for some occasions that require fast startup.

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