Sampling period online adjusting-based hysteresis current control without band with constant switching frequency

Abstract

In this paper, a simple digital hysteresis current control (DHCC) with quasi-constant switching frequency (SF) for the current control of a single-phase grid-connected inverter (SPGI) is proposed. The hysteresis band is cancelled, and the SF is fixed by online adjusting the sampling period. The principle of the DHCC with constant sampling period is analyzed, and the distribution of the switching period (SP) corresponding to the phase angle of the grid is derived. The rule of online adjusting the sampling period to fix SF is then determined according to the former theoretical analysis results. Furthermore, the effect of variation of the filter inductor on the SP is analyzed. An online estimation of the filter inductor based on the linear model of the current increment within one switching cycle is developed to eliminate this kind of effect. The proposed scheme shows the features of simple control, easy implementation in a digital way, robust to the filter inductor, and excellent steady and dynamic performance. The detailed simulation and experimental results verify its accuracy and feasibility.

Application Research of Chaotic Carrier Frequency Modulation Technology in Two‐Stage Matrix Converter

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Suppression of the Second Harmonic Subgroup Injected by an AC EAF: Design Considerations and Performance Estimation of a Shunt APF

“…The most basic and effective waveform modulation technique for generating a current reference with a voltage source converter is to use hysteresis band modulation philosophy [38][39][40][41][42][43][44]. The hysteresis band modulation technique has been widely used in the literature for APF systems [25,43,44] due to its advantages, like easy implementation, dynamic stability, controllability on current, and perfect tracking of the reference signal [25,44].…”

Hysteresis band current controller based field-oriented control for an induction motor driven by a direct matrix converter

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