Control arrangement for self-guided inverters

Claim 1

IN A CONTROL DEVICE FOR SELF-GUIDED INVERTERS WITH A PULSE NUMBER P FOR THE PRODUCTION OF M NUMBER OF A.C. VOLTAGES HAVING A FREQUENCY F FROM A SOURCE OF DIRECT CURRENT AND WHEREIN P/M=1, 2..., THE COMBINATION COMPRISING A VOLTAGE GENERATOR PRODUCTING A SAWTOOTH VOLTAGE WAVE AT A FREQUENCY P.F, CIRCUIT MEANS COMBINING SAID SAWTOOTH VOLTAGE WAVE IN SERIES OPPOSITION WITH A D.C. VOLTAGE TO PRODUCE A SECOND SAWTOOTH VOLTAGE WAVE AT THE SAME FREQUENCY P.F AND HAVING A ZERO PASSAGE POINT, A PULSE SHAPER FED BY SAID SECOND SAWTOOTH VOLATAGE WAVE AND PRODUCING AT ITS OUTPUT A SHAPED PULSE AT EACH ZERO PASSAGE POINT IN SAID SECOND SAWTOOTH VOLTAGE WAVE, A FREQUENCY DIVIDER FED FROM THE PULSE OUTPUT OF SAID PULSE SHAPER, SAID FREQUENCY DIVIDER HAVING A P NUMBER OF OUTPUTS AND A DIVISION RATIO OF 1:P AND PRODUCING AT SAID OUTPUTS P NUMBER OF SYMMETRICALLY DEPHASED IMPULSE SERIES OF A FREQUENCY F, MEANS TRANSFORMING THE OUTPUTS FROM SAID FREQUENCY DIVIDER INTO POTENTIAL SEPARATED CONTROL IMPULSES AND MEANS APPLYING SAID CONTROL IMPULSES TO THE VALVES OF THE INVERTER.