سیستم کنترل هوشمند برای مدیریت انرژی بهینه در ساختمان های تجاری Intelligent Control System for Efficient Energy Management in Commercial Buildings

I. INTRODUCTION Day by day the energy demand is increasing. This is required to meet the advancement in all areas of any nation. Also, modern power systems face certain challenges such as environmental concerns, high requirements of reliability, growing social and industrial demands etc. All these requirements cannot be satisfied by the utility grid alone. Microgrid is an important promising technology to meet all these requirements. In a commercial building, the productivity and quality of life of the people depends on the comfort level within it. Visual and thermal comforts are the main comfort factors [1]. These are provided by lighting and air conditioning systems. The more the comfort level provided, the more is the energy consumption [2]. Energy scarcity, these days, necessitates a balance between the energy consumption and the customers’ comfort. Energy can be saved to a great extent by properly managing the energy while ensuring reliability of the critical loads. This also minimizes the total energy consumption [3]. The saved energy can be utilized later by the critical loads. The intelligent energy management system used in commercial buildings can serve multiple purposes, like reducing the total energy consumption, ensuring effective and efficient use of energy, ensuring supply to the critical loads, and minimizing the energy wastage [1] [4]. The remainder of the paper is organized as follows: Section II describes the overall system layout. Section III describes the microgrid including the renewable energy sources such as photovoltaic (PV) arrays and wind generation and the battery energy storage system for storing surplus energy. The design of the intelligent control system is detailed in Section IV. In Section V, the fuzzy logic controllers are explained with the fuzzy rules. Section VI gives an idea about the intelligent energy management done in a smart building. In Section VII, the control scheme is explained in detail. In Section VIII, the model used for simulation and the results are presented. Finally, conclusion is given in Section IX. II. SYSTEM LAYOUT The increasing challenges faced by modern power systems cannot be satisfied by the utility grid alone. Microgrid is an alternative solution for the same [5]. The commercial building, under consideration in this work, is supplied with the microgrid, which uses renewable energy sources. This makes the building self-reliant. Here, the renewable energy sources used are the PV Arrays and wind turbine [6], which are eco-friendly and avoid environment pollution. Power generated during off-peak hours is stored using battery energy storage system (BESS) [7]. The stored energy can be utilized later when required. Microgrid is located close to the controllable loads, which improves reliability and reduces the transmission losses. Microgrid can be connected to and disconnected from the utility grid when required. Therefore, energy exchange between the grid and microgrid is possible whenever required. Moreover, when there is utility failure, the microgrid can work as an autonomous grid by supplying the loads connected to it [8]. The control system for the smart building utilizes the intelligent multi-agent system technology [4]. This consists of multi-layered agents for the control. The comfort factors under consideration include visual and thermal comforts [1]. Therefore, the critical loads are the lighting and airconditioning systems, which provide visual comfort [9] and thermal comfort respectively in the commercial building. Through the action of these multilayered agents, the control system minimizes the energy consumption ensuring the customers’ comfort [1].