RESEARCH OF AN ACTIVE FILTER-STABILIZER BASED ON A PULSE WIDTH CONVERTER

Under the conditions of increasing loads on sections of the direct current traction network, traditional measures no longer ensure high-quality and efficient functioning of the traction power supply system. In previous works, the authors of this article proposed incorporating an active filter-stabilizer based on a single-phase bridge converter circuit into the converter unit of a traction substation. The purpose of this approach is to improve the quality of direct current electrical energy and enhance the electromagnetic compatibility of the direct current traction power supply system with adjacent electrical installations.The active filter-stabilizer based on the bridge converter circuit can be simplified by implementing it using a buck-type pulse-width modulation (PWM) converter structure. The article presents the results of a study on the active filter-stabilizer based on a buck-type PWM converter within the converter unit of a direct current traction substation. The synthesis of the circuit and control algorithm for the active filter-stabilizer based on the buck-type PWM converter structure has been carried out. A closed-loop automatic output voltage regulation system for the converter unit with the new variant of the active filter-stabilizer is proposed.Using modeling in the MATLAB environment, the functionality was verified and the quality indicators of the direct current electrical energy of the converter unit with the active filter-stabilizer based on the PWM converter were analyzed.The research confirmed that implementing the power section based on the PWM converter structure indeed significantly simplifies the design of the previously proposed active filter-stabilizer and reduces the cost of its implementation at traction substations, while maintaining high performance in terms of direct current power quality and electromagnetic compatibility with adjacent electrical installations.