Power controller
US7936576B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 2004 |
| Grant date | May 3, 2011 |
| Priority date | — |
| Expiry date | Oct 27, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/081
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power controller (10) includes a controller (11) and a trigger circuit (12). When the voltage of a power supply received at terminals T1 exceeds a threshold, for example 120 V RMS, reverse-connected Zener diodes Z1 to Z3 conduct and switch on a transistor Q1. This results in a transistor Q2 being switched off and a normally open relay SW1 remaining open. The switching or triggering phase angle of a triac THY1 thus is determined by the speed at which a capacitor C4 is charged to a triggering voltage by current flowing through resistors R6, R7, R8 and VR1. In this situation, the triggering phase angle is such that a 240 V AC input supply provides an effective 110 V AC output at terminals T3 when VR1 is at maximum power setting (zero Ohms). When the voltage of the received power supply is less than the threshold, the transistor Q1 is switched off and the relay SW1 is activated. This bypasses resistor R6 and causes the switching or triggering phase angle to adopt a value of about zero degrees when VR1 is at maximum power setting, such that the voltage of the output power supply terminals T3 is substantially the same as that received at terminals T1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.