Energy controller for conversion from a direct current source to a variable frequency load
US4277736A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1979 |
| Grant date | Jul 7, 1981 |
| Priority date | — |
| Expiry date | Nov 30, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A turn off circuit for a multiphase motor is provided, comprising a D.C. powered system including a three element choke core having two outer cores with loosely coupled windings and a central core closely coupled to the outer cores to enhance pulse generation. A modified SCR ring counter is provided to supply D.C. power to the load to produce a three phase wave shape with less wave distortion and lower noise. Pulse width modulation is supplied to the negative SCRs of the ring counter through steering SCRs which are turned on by discharge from capacitors in the steering circuit. Pulse width modulation is fed to the ring counter through the outer core elements, while the central core functions to improve pulse width of the discharge capacitors. Free wheeling energy from the motor is fed to the discharge capacitors and increases firing energy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.