The On-line Monitoring Of HVCB

On-line monitoring of HVCB is the precondition of predicting maintenance, is the key element of reliable run, and is the important supplement to the traditional off-line preventive maintenance In fact , the faults are made by HVCB, no matter in number or in times, is over 60% of total faults So it has determinative importance for improving the reliability of power supply And this can greatly decrease the capital waste used by-dating overhaulIn this paper, the inspecting way of HVCB mechanism characteristic is discussed The concept of sub-circuit protector is presented, the scheme that we offered has been combined with sub-circuit integrality monitoring theory, to ensure that it has the two functions as a whole According the shut-off times at rated short circuit given by HVCB manufacturer, the electricity longevity loss can be calculated in each operation, and the remained longevity can be forecast too An indirect way for calculating main touch's temperature by using breaker shell temperature , air circumference temperature and breaker's heat resistance is improved in this paper, and main touch resistance can be calculated if providing the load current MSP430 , a new Single Chip Microcomputer made by TI company , is engaged to develop the hardware system of the on-line monitoring device, and special problem brought by the lower supply voltage range of this chip is considered fully. In the design of communication module, the interfacing problem of different voltage chips (MAX 1480 and MSP430) is solved, and a connection scheme is given in this paper as well...