Determination of the input filter parameters of the active rectifier with a fixed modulation frequency

Abstract

Goal. Development of a methodology for calculating the parameters of the active rectifier-voltage source input filter operating with a fixed modulation frequency to ensure electromagnetic compatibility with the supply network acceptable by standards at minimum values of the input inductance and checking its main characteristics on a mathematical model. Methodology. The authors have developed a methodology for calculating the parameters of the input filter of an active rectifier-voltage source. The calculation results are verified on the constructed mathematical model of a frequency converter, the scheme of which is an active rectifier and an autonomous voltage inverter. A series of experiments was carried out on a mathematical model to study the dependence of the total harmonic distortion of current and mains voltage on the value of the input inductance for various parameters of the input filter. Results. The structure and calculation procedure the input filter of an active rectifier operating with a fixed modulation frequency are proposed. The simulation results showed that the inclusion of a filter at the input of the active rectifier significantly improves its electromagnetic compatibility with the supply network in the entire range of variation of the input inductance of the circuit and makes it possible to achieve the values of the total harmonic distortion permissible by the norms. Originality. A structure and a calculation procedure the input filter of an active rectifier-voltage source operating with a fixed modulation frequency are proposed. Practical significance. The dependencies obtained in the article allow us to evaluate the relationship between the parameters of the filter elements and its characteristics among themselves and come to a compromise between them when designing a scheme for specific technical conditions.

Active rectifier with a fixed modulation frequency and a vector control system in the mode of bidirectional energy flow

“…For AVIs operating in the range of small and medium powers, pulse width modulation (PWM) has become the most common. Having a relative simplicity of implementation, it provides a fixed switching frequency of valves switching in the circuit, which significantly simplifies their thermal calculation, and also facilitates the calculation of filters at the output of the circuit [4,5].…”

“…Thus, the control system proposed by the authors has, compared to the known, the following advantages: it reduces the number of regulators in the system to two; does not require calculation of d-q voltage components; does not require the calculation of trigonometric functions in the process of coordinate transformation. The model has the same parameters that were adopted by the authors in previous studies [4], namely: the three-phase AC voltage source with short-circuit power of 150 MVA and the linear voltage at the converter input of 400 V; the value of the input inductance of the phase is taken equal to 400 µH; the DC link capacity 28 mF; the ARVS operates in sinusoidal PWM mode with fixed modulation frequency of 4 kHz and the vector control system made according to the structure (Fig. 4).…”