A Voltage-Feed High-Frequency Resonant Inverter With Controlled Current Output as a High-Frequency AC Power Source

A current-based power distribution is presented for the applications of high-frequency ac power distribution system (PDS). Comparing with the traditional voltage-based counterpart, the current-based system can be applied into some specific applications, such as high-voltage gate-driving system, contactless power transmission, etc. A modified resonant topology based on LCL-T tank is proposed to implement high-frequency current source. The effective magnitude control and high conversion efficiency are both achieved. First, the proposed topology is examined with circuit principle, operational cycle analysis, and soft-switching description. Second, the phase-shifted control scheme is explored to calculate the equivalent resonant capacitor of LCL-T resonant tank, as well as the relations between current gain ratio and phase-shifted angle control are discussed in depth. Finally, the simulation model and experiment prototype are implemented with rated peak current of 2 A, rated output frequency of 30 kHz, and rated output power of 50 W. The experimental results in accordance with simulation prove that the constant current characteristics are maintained with high conversion efficiency. Hence, the proposed circuit topology and control scheme are a feasible realization of current source that is used to feed high-frequency PDS.