ساختمانهای هوشمند برای پشتیبانی فرکانس سیستم قدرت
Abstract
1- Introduction
2- System modelling
3- Proposed control framework for GISBs
4- Results and discussions
5- Conclusions
References
Abstract
Grid-interactive smart buildings with thermostatically-controlled loads can be modeled as virtual energy storage systems with dissipation, which have great potentials for providing grid ancillary services such as frequency support. In this paper, a new distributed aggregation control method is proposed for multiple grid-interactive smart buildings in one frequency control area (e.g. a residential community) to provide fast frequency support. The proposed method is based on the distributed sliding mode control via a leader-follower communication scheme. A leader control is designed to provide power and comfort/energy level references for the smart building aggregator based on the area frequency deviation, while references are tracked by each smart building using the proposed distributed sliding mode control. The stability of the proposed control method for grid-interactive smart buildings is proved by the Lyapunov method. With the proposed method, the external characteristics of the aggregated smart buildings will have good power tracking and energy recovery capability, which can effectively improve the system frequency response. In the aggregator, fair and efficient power and comfort/energy level sharing are achieved among all participating grid-interactive smart buildings. The proposed control scheme is tested on a three-area power system considering both system contingency and normal operation scenarios.
Background and motivation
In the last decade, the penetration of renewable energy resources into modern power systems is increasing rapidly. For example, in Singapore, the projected photovoltaics (PVs) generation will be increased to 350 MWp by 2020 [1]. However, high penetrations of renewable energy sources (RESs) such as solar PV and wind power have reduced power system inertia by replacing the synchronous machines [2], which can significantly challenge the system frequency regulation [3], control schemes [4] and transient stability [5]. In the meantime, fast and stochastic power variations of RESs will also lead to rapid frequency fluctuations [6]. It is well known that the power system frequency is an indicator of real-time power balancing between generation and consumption. So the frequency regulation becomes quite important in order to maintain a stable and efficient operation of the power systems. The severe frequency deviations can lead to load/generation trip-off, which jeopardize the stability and security of power systems as well as decline energy efficiency. A possible way to deal with the negative impact of renewable penetration is to increase the spinning reverses from power plants. However, involving more spinning reserves will bring additional fuel consumption, which is not an economic and energy efficient way to handle this problem.