| 摘要 |
PURPOSE:To ensure an immediate switching to the auxiliary oscillator in case some trouble occurs for the reference signal generator by adding the auxiliary oscillator synchronized with the working oscillator in case the parallel operation is given to the constant voltage and frequency (CVCF) inverter. CONSTITUTION:For three units of CVCF inverters A-C to be given the parallel operation, the reference frequency signals are applied in common to control units 1-3 through wire 4. Each inverter contains oscillators 5-7, dividers 8-10 to divide the oscillators plus synchronous pulse generators 14-16. And only switch 11 constantly used for the oscillator consisting of oscillator 5 and divider 8 along with other switches 12 and 13 opened, and the output of divider 8 is supplied to inverters A-C. In case some fault occurs to the oscillator of inverter A, switch 11 is opened with switch 12 closed via pulse generators 14 and 15. In order to avoid the phase shift caused by switching, the divider of the auxiliary side is reset with a fixed cycle by the working division output. |
