Study on Emergency Generator Capacity Selection(PG3) in the Chemical Plant

화학 플랜트에서의 비상발전기 용량선정 방안(PG3)에 관한 연구

  • Received : 2015.09.05
  • Accepted : 2015.10.15
  • Published : 2015.12.31


PG and RG methods are widely known method for calculating the capacity of the emergency generator in construction electrical installation. PG and RG methods are mainly used as a saving a life, fire protection, fire fighting in construction. Because no long distance between the emergency generator and electric motor feeder, the relatively small motor power in construction electrical installation, the capacity of generator in PG and RG methods are little problem of voltage and reactive power of generator. However in many cases the application of the PG and RG method is difficult in the Chemical Plant because it is long distance between the generator and the motor Feeder and motor capacity is very large. Motor starting power factor is about 0.2 lagging power factor and motor starting current is about 6times during motor staring. Also Most of the staring current component is a reactive power component. therefore, it is many cases that lack of reactive power and excess of allowable voltage drop limit and After selection of emergency diesel generator, problems happen during motor starting. Therefore, to be selection of effective emergency generator, active generator power, reactive power and the required reactive power during large motor starting should be considered in chemical plant. It is also required of the verification process through simulation because hand calculation is very difficult considering study cases.


Emergency Generator;Motor Starting;Reactive Power;Active Power;Voltage Drop


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