INVERTOR ASSOCIATED ASYNCHRONOUS THRE-PHASE ROTARY MOTORS DRIVING SYSTEM

摘要

Inverter associated asynchronous three-phase rotary motors driving system. The system, according to the invention, assures the operation during the acceleration of the asynchronous three-phase rotary motor with constant sliding on intervals for electromagnetic efficiency approximately equal to the rated operating regime of the asynchronous rotary motor, constant, by electronic modelling of three relations. In one of these, one of the factors for constant electromagnetic efficiency will be the sliding. The electronic scheme is conceived to provide the automatic maintaining of the sliding for constant electromagnetic efficiency as a constant, using in this respect only common electronic circuits like: a tachogenerator for resistive dividers, three operational amplifier adder circuits, a frequency prescription circuit, a voltage-frequency converter, a dividing circuit, a triangle shaping circuit, a sinusoid shaping circuit, three comparison circuits, three interconnected impulse amplifiers. The system is used in electric driving systems with asynchronous rotary motors characterized by difficult and frequent activations, to avoid the inefficient functioning during acceleration.