Saichol Chudjuarjeen

Asymmetrical control with phase lock loop for induction cooking appliances

This paper presents an asymmetrical control with phase lock loop for series resonant inverters. This control strategy is used in full-bridge topologies for induction cookers. The operating frequency is automatically tracked to maintain a small constant lagging phase angle when load parameters change. The switching loss is minimized by operating the IGBT in the zero voltage resonance modes. The output power can be adjusted by using asymmetrical voltage cancellation control which is regulated with a PWM duty cycle control strategy.

A variable-frequency asymmetrical voltage-cancellation control of series resonant inverters in domestic induction cooking

The variable-frequency asymmetrical voltage-cancellation (VFAVC) control is proposed in this paper to control the output power for a series resonant load with a full-bridge inverter for home appliance as induction cooking. The asymmetrical voltage-cancellation is used for controlling the output power. With the low quality factor loads, a fixed-frequency control might lead to non-zero-voltage-switching (NON-ZVS) operation. The proposed control strategy ensures the ZVS operation for switching loss reduction by varying the switching frequency slightly higher than the resonant frequency. By using the ZVS constant, the new control strategy is proposed by varying the switching frequency according to the output power. Moreover, this proposed control can improve the overall efficiency of inverter system. The experimental results are given in this paper to verify the proposed control method.

A dual output series resonant inverter with improved asymmetrical voltage-cancellation control for induction cooking appliance

This paper presents a dual output full-bridge series resonant inverter with improved asymmetrical voltage-cancellation control for induction cooking appliance. The proposed control scheme can adjust the output power separately, and achieves the zero-voltage switching (ZVS) condition with improved efficiency. A laboratory prototype has been implemented on a DSPIC2010 controller. The experimental results are presented to validate the proposed control scheme.

LCCL series resonant inverter for ultrasonic dispersion system with resonant frequency tracking and asymmetrical voltage cancellation control

This paper presents a high efficiency LCCL series resonant inverter for ultrasonic dispersion system with resonant frequency tracking and asymmetrical voltage cancellation control. With the proposed control, the operating frequency of the inverter is automatically adjusted to track the resonant frequency under load parameter variation due to surrounding condition. The zero-voltage switching (ZVS) is maintained throughout the operation. The output power is controlled using the asymmetrical voltage cancellation (AVC) technique. A full-bridge hardware prototype is constructed and the control algorithm is implemented using an STM32F4 microcontroller. Computer simulation and hardware experiment are provided at an operating frequency range of 37-42 kHz and the output power of 30-125 W.

Quasi-resonant converter for induction heating in high temperature applications

This paper describes quasi-resonant converter for induction heating in high temperature application. Converter is implemented by using IGBT as its switching. The switching loss is minimized by operating the IGBT in the zero voltage resonance modes. The output power can be adjust by varying the switching frequency of converter. The prototype is tested under load-parameter variation during the heating process and it is rated at approximately 1000W, with operating frequency ranging from 5-7 kHz. The operation principles of quasi-resonant are investigated and validity is verified by simulation and experimental results.

Half bridge voltage source inverter using frequency and temperature control for induction distilling applications

Half bridge voltage source inverter using frequency and temperature control for induction distilling application is proposed in this paper. Switches devices operate in zero-voltage soft switching mode. The system has been operated at 17–40 kHz. The output power transferred to the load is 1,262 watts. It can boil the water to vapor at the efficiency around 90–94%. Experimental studies have confirmed the validity of the proposed method.

Automatic variable frequency asymmetrical control of half-bridge series resonant inverters for low-cost domestic induction cooking

This paper presents a digital implementation of power control for induction cooking appliances with domestic low-cost vessels. The proposed control strategy is based on the asymmetrical duty-cycle with automatic switching-frequency tracking control employing a digital phase locked-loop (DPLL) control on high performance microcontroller. With the use of a phase locked-loop control, this method ensures the zero voltage switching (ZVS) operation under load parameter variation and power control at any power levels. Experimental results have shown that the proposed control method can reach the minimum output power at 15% of the rated value.

A combined PDM and AVC control for induction cooking appliances

This paper presents a combined pulse density modulation (PDM) and asymmetrical voltage cancellation (AVC) control for induction cooking appliances. The average output power can be adjusted by the varying output voltage waveform, which achieves the zero-voltage switching (ZVS) condition, and reduced the power losses on the IGBT switches. The proposed control improves the efficiency at the low power level as well as increases the power range operation. The simulated results using the PSPICE program verify the proposed control scheme.