Control arrangement and method for high-speed source transfer switching system
US5808378A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1996 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Dec 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J3/38
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control arrangement and method is provided for high-speed source-transfer switching systems (HSSTSS). The HSSTSS supplies an electrical load with alternating current from either a first source or a second source via respective first and second solid-state switches. The HSSTSS also includes a controller that samples the voltage waveforms of each of the first and second sources to detect when transfer between the sources is desirable, e.g. outages or voltage that is either too low or too high. The controller provides appropriate control signals to control operation of the solid-state switches and transfer supply of the load therebetween. The control arrangement avoids undesirable current flow between sources via a comparison of the voltages of the sources and current in the outgoing source, i.e. a polarity comparison to ensure that the current that will flow in the incoming source after transfer will be in opposition to the current flowing in the outgoing source before transfer. Thus, the transfer is delayed until the polarity comparison is satisfied. Either separately or in combination with the polarity comparison, the control arrangement minimizes undesirable transfer delays by e…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.