The Role of Synthetic Inertia and Effective Load Modelling in Providing System Stability as Renewable Energy Penetration Increases

Abstract

Recently, wind power penetration has increased to offset the reduction in fossil fuel generated power. To ensure the power system continues to function adequately, some grid operators require an inertial response from the wind turbines. Synthetic inertia, or the combined inertia from individual wind power turbines in a wind farm, can provide a measured inertial response to the system under various wind power penetration levels. However, the response to the system due to the synthetic inertia from the turbines may not be adequate to assist in the stability of the system due to its rapid response time, usually in the range of a couple of seconds. In this paper, effective load modelling is merged with the effects of synthetic inertia to discover what role these two methods can have on stability in the power system. The Alberta interconnected electric system (AIES) is used to test the proposed hybrid model. Alberta is an energyonly deregulated market. It is expected a higher volume of renewable energy will be added to the power systems everywhere including the AIES. The increase in renewable penetration may result in transient stability challenges. This paper explores how synthetic inertia and load modelling can facilitate a system stability opportunity. Further, the paper examines how synthetic inertia and load modelling can perform under various wind power penetration levels within the Alberta power system. Finally, the response of the inertial model is demonstrated through detailed simulations.