Study of half‐bridge series‐resonant induction cooker powered by line rectified DC with less filtering

Abstract

This paper presents an analysis and design strategy for a half‐bridge series resonant induction heating (HB SR‐IH) cooker powered by a rectified sinusoidal DC. The simplified equivalent circuit of an induction cooker is modelled by a train of rectified sinusoidal DC pulses chopped at the switching frequency. An average root‐mean‐square (RMS) method is proposed to calculate the RMS resonant voltage and current extrapolated to the power line frequency period. The stability of the cooker is achieved by properly setting the damping ratio in the root‐locus plane to keep the system running quasi‐resonantly at the required power. The power control of the SR HB‐IH cooktop is performed by forced commutation above the resonance frequency. A prototype of a 3 kW HB SR‐IH cooker was designed and implemented to validate the estimated results. Various waveforms from low power to high power are discussed and verified by damping ratio control. The SR HB‐IH cooktop achieves a high‐power factor of 0.95 to 0.995 when generating 300W to 3kW due to less filtered DC power. The power quality assessment showed that the total harmonic distortion (THD) of the line current and voltage measured at 3 kW was 4.1% and 3.5%, respectively.

Design Methodology of Series Resonant Half Bridge Inverter for Induction Cooker

“…In domestic induction applications, the filter used after the rectifier increases the power factor and at the same time ensures compliance with IEC/EN 61000-3-2 tests [22], [23], when frequency modulation is selected in continious conduction mode operation. However, in HBSR inverters using frequency modulation, the power transferred to the resonant circuit decreases as the switching frequency is increased.…”

“…Up to this point, the HBSR design studies conducted can be categorized into three fundamental groups: circuit design and analysis, coil design and control. As examples of circuit design and analysis studies, references [3], [8], [12], [18]- [22] can be cited. And also in the literature, numerous studies can be found that examine the effects of the pot used in induction heating cookers on the resonant circuit Almost all these studies explain the relationship between the pot and the coil using modeling methods resembling an R-L circuit [11], [14], [23]- [27].…”

“…In all the studies [3], [5], [8], [12], [18]- [22] related to the design of the circuit, the main converter and component values (equvilent R, L, C) were found and it was not taken into account whether a coil suitable for these values could be produced. Consequently, due to the challenges in both calculations and simulation for coil with pots, it is not possible to find a comprehensive design for induction cookers in the literature that includes the details mentioned above..…”

Design Consideration of ZVS Single-Ended Parallel Resonant DC-DC Converter, Based on Application of Optimization Techniques

“…In this sense, due to their wide distribution and cost advantages, special designs of semiconductor elements have been developed to meet the specific needs and requirements of these devices [9,12]. In [13,14], various schematic options for the implementation of induction hobs are considered, basic design ratios are given and a method for recognizing the load is proposed, thanks to which the device operates with minimal losses. A natural development of single-ended transistor DC/AC converters are DC/DC converters.…”

A Simplified Design Method for Quasi-Resonant Inverter Used in Induction Hob

“…Numerous studies have been conducted on coil design, particularly in the context of magnetic fields Different resonant inverter topologies have been proposed based on the trade-off between cost and performance, which needs to be evaluated for each specific application. The most common inverter topologies in induction heating (IH) systems are half-bridge series resonant (HBSR) [25][26][27][28] and single-switch quasi-resonant (SSQR) [29][30][31] inverters. The SSQR inverter topology provides a reliable solution for low-power and low-cost IH applications.…”