Patent · US Expired

Electrostatic precipitator rapper control system with enhanced accuracy

US4255775A · kind A · utility

11Cited by
15References
28Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 29, 1979
Grant dateMar 10, 1981
Priority date
Expiry dateMay 29, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M1/088
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A comprehensive multiple rapper control system controls rapping intensity with enhanced accuracy, controls a large number of rappers in any desired sequence with intensity control for each individual rapper, and includes alarm circuitry for reliably indicating open circuited and short circuited conditions in the rapper coils or in the electrical connections to the rapper coils. For enhanced accuracy, a short boost pulse of full lift energy is applied immediately prior to a lift pulse of controlled energy. The boost pulse overcomes initial rapper plunger sticking forces so that total rapper plunger lift accurately reflects the electrical energy supplied during the subsequent controlled pulse. Advantage is taken of the relatively constant boost pulse which is supplied to every rapper in the system regardless of the energy supplied during the control pulse to provide an alarm circuit. Current through each rapper plunger lift coil is sensed during at least a portion of the boost pulse. An alarm condition is signaled if this sensed current is outside of a predetermined range.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.