Improving Controllability of Conventional Power Plants using Voltage Angle Control

Abstract

Abstract In the future, most of the fossil fuel based power plants of today will progressively be replaced by complete inertia-independent systems. Such systems, referred to as slack storage power plants, will consist of power electronic converters and storages in order to store power from renewable sources. However, some of the conventional thermal and hydroelectric power plants of today will remain in operation and act as base power plants in the power grid. In this paper, a method is proposed which will govern the electrical power distribution in a network containing both conventional and the novel storage power plants. All the control principles existing at present involving spinning reserve, primary and secondary control depending on frequency are substituted by a comprehensive angle control of the nodal voltages in the transmission and distribution network. With this control method in place, whenever there is a change in the power requirement of the network, the power plants react instantly with the ones closest to the point of disturbance providing the greatest response. During the excessive power generation from renewables, the storage power plants can boost their power reserve. This allows the conventional power plants to continue operating within permissible thresholds. Not only does this method help to produce more power closer to the point of load demand, reducing the stress on the generators located further away, but it also improves the controllability of conventional power plants leading to lower operational losses.