ABSTRACT
Now that we have studied the essentials of direct current (DC) and alternating current (AC) circuits, transformers, generators, three-phase circuits, and AC power, in this chapter we will describe the major components and workings of a typical electrical power system or grid. A typical power system consists of three major components: generation, transmission, and distribution. After reviewing these components, this chapter describes models of transmission lines. Then we introduce the bus admittance matrix, its use to calculate voltage and current, and to setup and solve power flow equations. We follow with a study of varying demand from the loads and the load-duration curve. We conclude emphasizing that a large grid is a complex dynamic system that requires tools from real-time control systems. We simplify the presentation substantially from material contained in textbooks devoted to electrical power systems [1,2] and the integration of renewable generation with power systems [3].
A typical power system consists mainly of three major components: generation, transmission, and distribution (Figure 11.1). Traditionally these components have been mainly based on three-phase AC systems. However, a modern power system also includes DC generation and transmission components because more renewable power systems are available and the technology of high voltage DC-AC and AC-DC conversion has been greatly improved. Recall the concepts of AC-DC, DC-AC, and DC-DC converters that we covered in Chapters 5, 8, and 10.
