In the type, the SG3--satisfies the generator capacity, KVA, which allows the voltage drop calculation when the large capacity motor is started.
The reactance of the Xd--generator, for the generator transient reactance X'd and the secondary transient reactance X''d arithmetic mean value, namely Xd= (X'd+X''d)/2, when the product sample is not found, xd generally desirable 0.15~0.3;
Δ U--start when the bus allowed voltage drop, generally desirable 0.25~0.3V;
According to the previous three requirements, after the diesel generator capacity, if SG2, SG3 than SG1 larger, then the motor starting mode need to make appropriate changes. When choosing the capacity of diesel generators, it is necessary to analyse the small-capacity generator set for the motor step-down starting, or the motor directly starting to select the larger capacity generator set, which should be determined according to the comprehensive technical and economical comparison.
4 Data center engine room Diesel Generator Select instance
Among the power loads, the refrigeration host power is 340.2kW (maximum capacity motor), the pump is 45kW, all three uses