Improvement of optimizing operation method for energy saving of large electric machine in combined heat and power plant

This paper presents an improvement in the optimization of operation method of large electric machine for energy conservation in combined heat and power plant (CHP). The third power plant of CHP (CHP3) is placed in Ulaanbaatar, Mongolia. CHP3 of a coal-firing plant is expected to make Ulaanbaatar a smart city because the utility grid cannot control its plant at present. Since CHP3 needs to realize energy making instead of a new plant, one of the utility control methods is to use a battery. Therefore, energy saving is the way to make more energy. When an inverter driven mode is used for a large electric machine of boiler feed water pump (BFP) to save energy from a conventional motor driven mode, the improvement in the optimization method reduces the throttle loss of the plant system. The amount of energy saving and control method are evaluated by a simulation using the inverter driven BFP. As a result, the energy saving can be expected as 24.9% at rated, 39.4% at 80% of boiler load, and 50.5% at 60% of boiler load for improvement using by optimization. This excellent result also reduces greenhouse gas emission in CHP3 using coal.