Decoupling output power control of two series resonant inverters sharing resonant capacitor for domestic induction heating

Abstract

Domestic induction heating applications require an accurate control of the power delivered to the vessel to be heated, ensuring power topology operation under safety conditions. Particularly, this paper is focused on applying a power control of two induction heating loads in a dual-half bridge sharing a common resonant capacitor. This topology leads to a control strategy harder than the classical arrangement which features a dedicated resonant capacitor. A Phase Shift Square Wave Modulation (PSSWM) is performed to control the output powers of the vessels to be heated. Thus, the considered plant is a twoinput two-output (TITO) system. The two control inputs are (f sw , ) and the two outputs are (P 1 , P 2 ). Since the transfer function matrix is not diagonal, the Relative Gain Array (RGA) methodology is used to analyze if a multi-loop control is feasible. Due to the fact that the system is strongly coupled a centralized control must be applied. Therefore, the aim of the paper is to apply a decoupling control to handle the interactions. Simulation and experimental results in an induction heating prototype are performed in order to validate the proposed control technique.

Phase‐shift modulation in double half‐bridge inverter with common resonant capacitor for induction heating appliances

“…Therefore although some works focused on the classical control theory identifying the transfer function of the system can be found [33], it is usual that the control of such devices is performed by searching algorithms of the output power objectives with slow dynamics where the process is stated from a safe configuration, usually the maximum working frequency of the device, decreasing the switching frequency to achieve the desired power [34]. The latter strategy is applicable to control the switching frequency and the phase-shift between the inverters of the topology proposed in this paper, or, alternatively, by applying search algorithms of the objective output power, as appear in [35], or, even, applying the classical control theory [36]. It should be noted that, in the case of removing one of the pot acting as the system load, the inductor cooker control proceeds to disconnect the associated inverter; as a consequence, the control mode becomes a typical single half-bridge inverter.…”

Power estimation for dual half‐bridge inverter with common resonant capacitor

“…In [5], the small‐signal modelling of this topology is addressed. Moreover, control strategies for this specific topology have also been reported in the literature [6, 7]. Fig.…”

Efficiency analysis and heating structure design of high power electromagnetic thermal energy storage system

“…Induction heating devices have gained wide popularity due to the widespread use of power electronics and advanced control technologies. [5][6][7][8][9][10][11] This device consists of rectifiers, filters, and inverters, it is further controlled by a digital signal processor (DSP) or another highperformance digital controller. Various resonant inverter circuits and transducer structures are the main research directions for induction heating devices.…”