Method for controlling a resonant-mode power supply and a resonant-mode power supply with a controller

摘要

A method for controlling a resonant-mode power supply, the resonant-mode power supply comprising an assembly of switches (K1, K2, K3, K4), between which a resonant circuit with an output load is connected, and a controller (C) configured to stabilize output voltages or currents by controlling switching frequency of the assembly of switches (K1, K2, K3, K4) in response to the output of a slow-response monitoring circuit (SMC) configured to monitor the output voltage or current and having a certain time (τ1) of response to changes of value of the output voltage or current. The power supply further comprises an energy recirculation circuit (ERC1) in which the current (Ilim) is monitored by means of a fast-response monitoring circuit (CMC1) having a time (τ2) of response to changes in the (Ilim) current faster than the response time (τ1) of the slow-response monitoring circuit (SMC). The method involves adjusting, via the controller (C), the switching frequency of the assembly of switches (K1, K2, K3, K4) such as to reduce the power supplied to the resonant circuit upon exceeding a threshold value by the current (Ilim).