Pulse by pulse current limit and phase current monitor for a pulse width modulated inverter
US5126647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1990 |
| Grant date | Jun 30, 1992 |
| Priority date | — |
| Expiry date | Apr 17, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An average current measuring circuit (40) in accordance with the invention includes a first switch (42) connected between a pair of reference potentials which has a duty cycle which is controlled by a control signal which pulse width modulates current flowing through the switch to a load and varies the current flowing through the switch in frequency; a first current transformer (44) coupled to the current flowing through the first switch for producing an output signal proportional to the current flow; a sampling circuit (46), coupled to the output signal, for sampling current magnitude when the switch is turned on; and an averaging circuit (60) coupled to the sampling circuit, for producing an average signal of successive samples of a current flow through the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.