Induction cooking application with multiple loads powered by suitable power converters and appropriate control technique needs attention. This study proposes dual frequency operated full-bridge inverter for multiple-load induction cooking. This inverter simultaneously powers two series resonant circuits. Each series resonant circuit is for one induction cooking load. This technique provides constant switching frequency operation for individual loads with asymmetrical duty cycle control. Output power of each load is independently controlled. The proposed inverter configuration and control technique is simulated and experimentally tested for two loads. Simulation and experimental results are in good agreement. This technique can be extended to more than two loads.

A three-leg resonant converter is proposed to drive two light emitting diode (LED) lamps of different power ratings. This may be required when both main and local lighting are essential. The proposed converter is operated simultaneously at two different frequencies. Two series resonant circuits are used to allow two different frequency currents. Each lamp is powered through a series resonant circuit and is controlled independently. LED lamp currents are regulated at the desired operating current by using phase-modulation control and asymmetrical duty ratio control. In addition, pulse-width modulation (PWM) dimming control is implemented for two LED lamps independently. The proposed topology has advantages of zero-voltage switching (ZVS), regulation of lamp currents, independent illumination control, and high efficiency. A 126-W prototype has been developed experimentally to confirm its working principle, performance, and validity.

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Induction heating (IH) technique has been widely used in industrial and domestic heating applications. In IH cooking applications, multi-output IH systems are increasing in demand. In this study, an inverter configuration is proposed for two-output IH cooking applications. The objective of this proposal is to reduce the component count and thereby the size of the circuit and cost. In this proposed configuration, two IH loads are connected to a full-bridge inverter output and these loads are sharing a common resonant capacitor. The output power is controlled using on-off control. Switching losses are reduced due to zero voltage switching operation. The two loads are independently controlled with high efficiency. The control logic of the proposed system is described in detail and prototype is designed, implemented and the validity is verified through experimental and simulation results.

This study presents a light emitting diode driver circuit topology based on a full-bridge configuration with dimming control. It is more suitable for high power lighting loads. The proposed configuration has advantages of zero-voltage switching, reduced component count and high efficiency. It can power multiple lighting loads. Operation of the proposed circuit configuration is explained in detail and it is validated through simulated and experimental results on the 145 W experimental prototype with dimming control.