The wide range of output frequency regulation method for the inverter using the combination of PWM and DDS

Abstract

Purpose

The specific modulation methods are used to control different kind of single-phase, as well as three-phase, inverters to ensure flexibility and high quality of the output waveform. This paper aims to present a combination of two classical methods, namely, pulse width modulation method and direct digital synthesis modulation method.

Design/methodology/approach

The total harmonic distortion of output waveforms of single-phase inverter based on elaborated modulation method has been determined by means of fast Fourier transform analysis. Tests have been carried out by using standard low-frequency application and also a wireless resonant energy link system.

Findings

Applying appropriate timer parameters of microcontroller enables to obtain a waveform for given output parameters (amplitude, frequency, frequency modulation index, etc.). The only limitation is the computing power of a microcontroller.

Originality/value

The elaborated method can be successfully used in both low- and high-frequency application ensuring high level of output waveform quality. Additional signal generators and the control of amplitude modulation ratio are no longer indispensable, what simplify immensely a control system.

Citation

Pietrowski, W., Ludowicz, W. and Wojciechowski, R.M. (2019), "The wide range of output frequency regulation method for the inverter using the combination of PWM and DDS", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 38 No. 4, pp. 1323-1333. https://doi.org/10.1108/COMPEL-10-2018-0402