Investigation of the Braking Mode of an Asynchronous Frequency Electric Drive with an Energy Buffer in the DC Link

In this study, an asynchronous electric drive powered by a frequency converter with a DC link, storage capacitors of standard and increased capacity, and additional pulse and inductive elements connected between the rectifier and inverter are considered. A system with an additional relay control of the current supplied to the inverter input from previously charged high-capacity capacitors was studied. A comparative simulation computer modeling of systems of a frequency asynchronous electric drive with vector control, with various electrical connection schemes and parameters of storage capacitive elements and additional pulse and inductive elements in the DC link, was performed. The time dependencies of the variables characterizing the operation of the electric drive and the processes of charging and recharging capacitors in the frequency converter in the motor and brake modes were obtained. An analysis of the obtained dependences is carried out, and the influence of the parameters of the power part of the circuit under study on transient processes in an asynchronous electric drive is established.