METHOD, ALGORITHM AND CONTROL STRUCTURE FOR STARTING AUTONOMOUS ASYNCHRONOUS GENERATORS BY USING AN ELECTRONIC POWER CONVERTER

摘要

The invention relates to a starting method, a starting control algorithm and a control circuit of autonomous asynchronous generators. The claimed starting method is applied to a voltage converter in the structure of a control circuit of an asynchronous generator and consists in adapting the V/Hz type starting specific to the scalar control of asynchronous motors, to the generator mode of the asynchronous machine. The claimed starting method implies the initial operation of an asynchronous machine in motor mode, the asynchronous machine being supplied with a voltage converter by means of an external source of direct current voltage, followed by the coupling of a driving motor and the passage thereof from the motor mode to the generator mode as the machine is accelerated. The claimed control algorithm consists in determining the reference frequency by means of a proportional-integral type regulator, then said frequency being converted into three reference signals applied to a PWM generator which generates six control pulses for some transistors which are included in the voltage converter. The claimed control circuit consists, on the side of the voltage converter, of a proportional-integral type regulator (), a memory block (), a pulse computation block (), a block () for the conversion of the pulse into three balanced and symmetrical sinusoidal signals, a limiter block (), a PWM generator (), and on the side of the ballast circuit, the circuit consists of a demultiplier block (), two proportional-integral type regulators () and a PWM generator ().