POWER SUPPLY UNIT WITH A SINGLE-PHASE CORRECTOR OF A POWER FACTOR FOR ELECTRIC DRIVES OF CONSTANT AND ALTERNATE ACTION
Abstract
The aim of the work is the development and investigation of the power supply unit, which is connected to a single-phase alternating current network and is intended for AC and DC drives with a pulse- width voltage converter. For motors with different rated voltages, the output voltage is regulated in the pow- er supply. To increase the power factor in the power supply, the active power factor corrector is used. The article describes the functional diagram of the power supply unit. The parameters of the main elements of the active power factor corrector are calculated. The synthesis of the control loop of the output voltage of the power supply unit is considered. The MatLab package has developed a mathematical model of a power supply with an active power factor correction and an output voltage regulation circuit, as well as a mathe- matical model of a simpler power supply without an active power factor corrector and without an output voltage control loop. On these models, the power parameters of both power supplies were analyzed with a change in the load power from 0.25 kW to 4 kW. The oscillograms of current and voltage that are consumed by the power supplies from the mains are shown at the same load capacity. The use of a power factor correc- tor makes it possible to increase the power factor and to ensure the consumption of a virtually sinusoidal current from a network that is in phase with the sinusoidal voltage. Using the voltage regulation system in the power supply allows you to adjust the average voltage value at the output of the power supply and use the same design of the power supply for DC and AC drives for motors with different rated voltages. The use of an uncontrolled rectifier at the input of the power supply does not allow the generation of energy into the network. For the recovery of electrical energy into the network at the input of the power supply, it is neces- sary to use an active rectifier.
