Energy Storage for Power System Planning and Operation

8Integration of Large‐Scale Energy Storage System into the Transmission Network

8.1 Introduction

Transmission expansion planning (TEP) is to decide where, when, and what type of new transmission lines should be built to supply the forecasted demand adequately [1]. A lot of research work on TEP has been carried out and published over the past few decades. TEP has drawn much attention from countries and regions with a rapid demand growth for electricity (e.g. China and Brazil) because of their imminent need for the expansion and reinforcement of transmission networks. In recent years, the increase in large‐scale renewable energy generation (REG) connected to power grids has brought more attention to TEP [2].

Mathematically, TEP is a problem of finding the least costly plan of constructing new transmission facilities to meet power transmission requirements under certain security constraints [3, 4]. In general, the TEP problem is a mixed‐integer, nonlinear and non‐convex optimization problem that is quite difficult to solve [5]. To build a tractable formulation, the linear model based on DC power flow is widely adopted for simplicity. The high uncertainty over future electric demand and supply during the planning stage also makes the linear model acceptable for engineering application. Different types of methods have been proposed to solve the TEP problem, which can be classified into three types: heuristic, mathematical optimization, and artificial intelligence (AI) (e.g. genetic ...