Commutating oscillator and current-limiter for solid state switching circuits
US4032825A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 28, 1975 |
| Grant date | Jun 28, 1977 |
| Priority date | — |
| Expiry date | Oct 28, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P3/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for use in a silicon controlled rectifier (SCR) control for direct current powered loads wherein the commutating voltage on the commutating capacitor is used to generate a gate pulse for the commutating SCR to thereby turn the main SCR off at a fixed and predetermined time after it has been turned on. The commutating voltage in the commutating capacitor is also monitored during charging thereof and the gate pulse for the commutating SCR is generated prior to the predetermined time in case the peak current through the main SCR reaches a predetermined excessive value. The gate pulse is also generated prior to the predetermined time during plugging or low-speed operation of motors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.