Patent ID: 9537422
Date: 2017-01-03
CPC Classifications: G05F,H02M,H05H,Y02B

Claim:
1. A high-frequency power supply, comprising: a direct current voltage source; at least one half-bridge drive circuit; a constant-current conversion circuit, and a series resonant circuit, wherein the direct current voltage source controls voltage of the at least one half-bridge drive circuit; the at least one half-bridge drive circuit comprises at least one pair of semiconductor switching elements, a control terminal of each of the semiconductor switching elements is connected to a secondary winding of a feedback transformer for switching alternately between an ON state and an OFF state, wherein the two secondary windings respectively connected to two primary windings of the feedback transformer with connection to the constant-current conversion circuit, the control terminal of each of the semiconductor switching elements is directly connected to a capacitor and the secondary winding of the feedback transformer, the semiconductor switching element is a metal-oxide-semiconductor field-effect transistor (MOSFET), and the capacitor is connected in parallel with the secondary winding of the transformer between the control terminal and a source terminal of the each of the semiconductor switching elements; the series resonant circuit comprises an induction coil, at least one capacitor and primary windings of the transformers connected in series, and a sum of reactance at a specific resonant frequency ω becomes zero; and the constant-current conversion circuit is a T-type constant-current conversion circuit or a π-type constant-current conversion circuit at the specific resonant frequency ω.