关键词: 水轮发电机组, 转动惯量, GD², 统计公式

Abstract: The moment of inertia plays a key role in the stability of a hydro-generator unit and the stability of the power system connected. For a hydro-generator unit, it is a key index for measuring its fast reaction performance and imposes a very significant influence on its stability; in engineering, the flywheel moment GD² is usually used to characterize its moment of inertia. In the design stages of pre-feasibility and feasibility studies, the GD² value is usually determined by estimation. This paper presents an analysis of the estimation formulas of two types commonly used for GD² estimation based on typical engineering cases and a large body of statistical data, and discusses how to choose reasonable GD² values. We use GD² data samples from the real hydropower units, which have been put into operation in China in recent years, to fit statistical formulas so as to lay a basis for calculation of the GD² of a hydro-generator unit in the initial design stage.

Key words: hydropower station, moment of inertia, GD², statistical formula