Wound rotor motor apparatus
US4415846A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 1981 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | Mar 9, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/062
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A wound rotor motor apparatus includes an energy recovery circuit having a rectifier connecting the rotor circuit to a gated inverter having an input filter for return of rotor power to the three-phase power supply system. A voltage chopper circuit connects the rectifier to the recovery inverter and operates to establish and maintain a constant direct current voltage to the inverter regardless of motor speed. The voltage is greater than the line voltage and is returned at near unity power factor. The chopper circuit is dual gated thyristors. A first thyristor connects an inductor in series to the rectifier. The first thyristor is turned on at the chopper frequency and current flows through the inductor. A commutating thyrister in series with diode is connected in series with a first thyristor and a parallel and back-biasing diode. An inductor in series with a capacitor is connected across commutating thyristor and the inductor-capacitor junction is connected in series with a dropping resistor to the input of the inverter filter. Upon turn-on of the commutating thyristor, the LC circuit tries to ring and current flows through the back-bias diode and turns the first thyristor off. Th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.