A method for sensorless rotational-speed determination of an asynchronous machine

摘要

A method for sensorless rotational-speed determination of an asynchronous machine, which has the following method steps:- a module for field-oriented control system calculates the voltages to be applied to the asynchronous machine, starting from a desired - value for the rotational speed, at least two measured values for the conductor current and a layer formed by an observer module calculated speed,- on the observer module, the voltage values from the field-oriented control system or the measured voltage values at which consists of the adjacent values a value for the moment-forming current isq (t) and an inner torque mi (t) of the asynchronous machine is determined,- a moment calculates the difference between the moment-forming currents from the field-oriented regulation and the observer module a to the asynchronous machine acting load moment ml (t),- a rotational speed module is calculated via the load moment of the moments module and the interior moment of the observer module the current speed of the asynchronous machine.