Home >> News

Considerations Of Frequency Converter In Mining Applications

Mar. 12, 2019

Frequency Converters are now finding wide use in mining applications. The majority of these frequency converters utilize adjustable frequency outputs that are created by rectifying the AC power source to DC then inverting this DC voltage back to AC working with a high frequency carrier and pulse width modulation (PWM) to create adjustable frequency, adjustable voltage distribution to the motor. They complicate the electric protection design in Many ways:

They introduce a new and complex voltage source into the power system. This may mean that earth faults can now be direct current (DC) in nature or may be driven by the inverter of the Mining Explosion-Proof Frequency Converter and so have a frequency that is primarily that of the frequency converter PWM carrier frequency (say 1000Hz for example).

The total outcome is that with regular ground leakage protection relays and electric system evaluations based only on consideration of flaws driven by the distribution system power frequency, security functionality is not likely to be sufficient if Intrinsically Safe Frequency Converter form a part of the associated loads.

Frequency Converters