| 摘要 |
FIELD: electricity. ^ SUBSTANCE: method for generation of double-frequency output current of inductor with the help of frequency converter, generating stepped voltage, consists in summation of voltages of several inverters, in calculation of control angles of each inverter depending on specified frequency composition, and generation of signals for inverters control. Amplitude and polarity of stepped voltage levels are specified with the help of transformation ratios of multi-element matching transformer connected by their primary windings with appropriate inverters. At the same time stepped multi-level voltage is generated by adding up of voltages of secondary windings of specified transformer. Own resonant frequencies of double-frequency resonant circuit are specified as equal to frequencies of synthesised harmonics, at the same time required ratio of required amplitudes of synthesised current harmonics are specified by parametres of double-frequency resonant circuit. Device for method realisation comprises frequency converter that generates voltage with specified harmonic composition, made of several inverters, outlets of which are connected serially, and control circuit including processor and connected to inverters. Device comprises multi-element matching transformer, primary windings of which are connected to specified inverters, and secondary windings are connected serially to make circuit of voltage summation connected to double-frequency resonant circuit made by two partial circuits: loading parallel circuit tuned for frequencies of required harmonics of inductor current and made of inductor and internal compensating capacitor, and external circuit made of throttle and external compensating capacitor. ^ EFFECT: simplified generation of required harmonic composition of inductor current with simultaneous increase of efficiency and accuracy of required temperature field generation in load. ^ 2 cl, 3 dwg |
