Electrical power conversion device and electric motor control system

摘要

An electrical power conversion device 50a; 50b; 50c; 50d includes: an electrical power conversion means 11 for converting DC electrical power into AC electrical power and supplying the AC electrical power to an AC electric motor 1; 14; a voltage output means 3; 12 for superposing, on a fundamental voltage command value, an alternating voltage at high frequency, and for outputting a result of the superposing to the electrical power conversion means; a high frequency component extraction means 5c; 13c for extracting from the current of the AC electrical power, as a high frequency current component, an amount of change due to the alternating voltage of a fundamental wave current component; a norm calculation means 5f; 13f for obtaining a high frequency current norm; and an superposed voltage amplitude adjustment means 9 for obtaining a superposed voltage amplitude command value based on the high frequency current norm, and for outputting the superposed voltage amplitude command value to the voltage output means 3; 12.