Inertia Theory Frequency Dynamic Analysis and Control of Power System with High Proportion of Renewable Source

Power plant emissions are a major cause of pollution in the environment. This necessitates the progressive replacement of conventional power plants with renewable energy sources. Changes in the quotas for conventional generating and renewable energy sources present new issues for modern power networks for example photovoltaic and wind turbines are replacing conventional power plants, which do not add to system inertia and due to the earth’s diurnal cycle and weather conditions. Solar radiations are not consistent all through the day, and photovoltaic (PV) generation is sometimes insufficient to meet the power requirement of the shifting local load. The amount of inertia in the power system, as well as the action of adjustable frequency reserves and the amount of power imbalance, all have an impact on frequency stability. As a result, estimating power system inertia and assessing frequency response are required so that necessary actions can be taken to assure frequency stability. In this way, the system frequency, power, and voltage stability are the major issues when high proportion of renewables are added. In this paper, we explained estimating power system inertia-related frequency problems. The approach account for the frequency and voltage fluctuations that occur after a disturbance and estimate the system’s total inertia constant as well as its overall power imbalance. The anticipated technique based on computational intelligence is used to analyze frequency responses from simulations of a test system under various circumstances on SIMULINK and focuses on the standalone PV system is critical for controlling it. As a result, the modelling of a PV system, battery, and generator using analogous circuits is discussed. As a matter of fact, maximum power should be harvested from a PV array to increase its efficiency that is depicted from the result outcomes of this research.

Investigation of Inertia Response and Rate of Change of Frequency in Low Rotational Inertial Scenario of Synchronous Dominated System

The shift to a sustainable energy future is becoming more reliant on large-scale deployment of renewable and distributed energy resources raising concerns about frequency stability. Rate of Change of Frequency (RoCoF) is necessary as a system inertia metric in order for network operators to perform control steps to preserve system operation. This paper presents in a straightforward and illustrative way several relevant aspects of the inertia response and RoCoF calculation that could help to understand and explain the implementation and results of inertial response controllers on power converter-based technologies. Qualitative explanations based on illustrative numerical experiments are used to cover the effects on the system frequency response of reduced rotational inertia in synchronous dominated power systems. One main contribution of this paper is making evident the importance of the governor action to avoid the synchronous machine taking active power from the system during the recovering period of kinetic energy in an under frequency event.

Fast frequency oscillations detection in low inertia power systems with excessive demand-side response for frequency regulation

The reduction in inertia present in electric power systems due to the increase in renewable generation interfaced with power converters presents various challenges in power system operation. One of these challenges is keeping the frequency of the system within acceptable bounds, as the reduced inertia allows faster changes in frequency. A possible way to mitigate this effect is to introduce a certain degree of frequency response in the demand side, in such a way that a loss in generation leads to a decrease in the demanded power, levelling the generation-demand balance. In this paper, one limitation of this approach is analysed, specifically the case where the demand response is excessive to the system inertia and demand, producing fast frequency oscillations. A scenario where this happens, on a simulated islanded system based on the electric power system of the island of San Cristóbal, in Galápagos (Ecuador), is studied, and a method of detecting these oscillations is proposed, as a first step to develop an appropriate response to them.