Programmable load controller
US4620283A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1983 |
| Grant date | Oct 28, 1986 |
| Priority date | — |
| Expiry date | Nov 29, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY04S20/222
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control method and system for minimizing the on-peak power demand of a residential electric utility user having a plurality of loads is implemented by determining the average energy demand over predetermined sliding time windows and comparing them with a control point. Non-priority loads are shed in an attempt to decrease the demand below the control point. If the energy demand is still above the control point after all non-priority loads are shed, the control point is dynamically adjusted upward and no priority loads are shed. Loads are shed by transmitting bits of information to the loads when the average energy demand over the predetermined time windows increases beyond the control point. Upon receiving bits of information indicating a load should be shed, the receiver deenergizes its load. The bits of information are synchronized to the zero crossing of the AC line. The bits are transmitted simultaneously and periodically. Central load control may decrease the power demand of the user in one or more predetermined steps. A method is provided for controlling multi-phase demand where the angles between phases are not necessarily equal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.