Patent · US Expired

High sensitivity battery resistance monitor and method therefor

US5969625A · kind A · utility

205Cited by
13References
21Claims
0Family size

Inventor

Key dates

Filing dateApr 16, 1997
Grant dateOct 19, 1999
Priority date
Expiry dateApr 16, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/392
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The method and the apparatus for detecting a deteriorating condition in a bank of standby batteries includes injecting an audio frequency current into one of the battery buses or cables, detecting an audio frequency current signal, matched to the injected audio frequency current signal, that is carried by the battery bus and detecting a voltage drop, at the audio frequency, across the bank of standby batteries. In one embodiment, current transformers are utilized in connection with an oscillator (to inject the AF current signal) and detection circuits (comparators and operational amplifiers) are utilized to generate a representative current signal and a representative voltage signal. The device detects when the standby batteries are operating in a normal, stable condition, that is, when the bank is neither being recharged nor is discharging DC power to the load. During normal, stable operating conditions, a differential relationship is established between the representative voltage and representative current signals. In one embodiment, a microprocessor-based system monitors the float voltage of the battery in order to ascertain when the battery system is in a normal, stable operati…

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