Current detecting apparatus and its control method
US6552562B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 2001 |
| Grant date | Apr 22, 2003 |
| Priority date | — |
| Expiry date | Jul 31, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0009
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
To reduce errors and decrease loss, the detecting range of current is enlarged and the current is independently detectable. A rectified voltage and a rectified current are supplied from an input terminal. Resistors 1 and 2 are serially connected between the input and output terminals. A load is connected to the output terminal. Between an emitter and collector of the transistor are resistor 1 and a constant current detecting circuit 5. The transistor base is connected to a control circuit that controls the transistor switching operations. The constant current detecting circuit 5 detects current from the voltage across resistor 1. A current detecting circuit 6 detects current from the voltage across resistor 2. A signal is supplied to the control circuit when the constant current detecting circuit 5 detects small current. The control circuit supplies a signal to the transistor base that increases transistor impedance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.