FIELD: electrical engineering, applicable in control systems of a resonance inverter with a pulse-duration modulation for induction heating units.
SUBSTANCE: the control method consists in formation and alternate supply of control pulses to the transistors forming the forward and back half-waves of current in the load. The novelty in the method is in the fact that first levels of the process parameter are preset that permit and prohibit the supply of control pulses. In operation the current mean value of the process parameter is measured for several last periods of the resonance frequency and compared with the preset levels. In the measured current mean value of the measured process parameters is less the preset permitting level, the permission to the supply the control pulses is authorized. Of the measured current mean value is greater than or equal to the level prohibiting the supply of control pulses, the permission to supply the control pulses is switched off with a simultaneous short-circuiting of the load input by power switching instruments of the long input. The method provides for control of current, voltage or power at the load, in this case the use of the circuit elements is enhanced, since current in the load flows uninterruptedly.
EFFECT: expanded functional potentialities due to provision of control of any of the following process parameters; output voltage, current and power, as well as enhanced range of adjustment of the process parameter at a supply of the electric load with parameters varying within a wide range.
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