Frequency control within high renewable penetration hybrid systems adopting low load diesel methodologies

Abstract

In the isolated power system, consumers are traditionally supplied with electricity produced by diesel generators. Conventional diesel generators demonstrate robust and efficient operation when connected to electrical grids with slowly varying loads. With the introduction of intermittent and stochastic renewable energy sources, such generators may not be responsive enough to retain the stability and reliability of the system. The problem becomes especially acute in cases when diesel generators are required to operate at a low load. Regulating devices (e.g. energy storage systems and/or dump load) used to improve the system reliability, increase system complexity and incur additional expenses or energy losses. This paper investigates low load diesel technology as a potential solution to high level renewable energy penetration. The focus is made on the engine time delay and the generator inertia constant that should be considered during the design of the isolated hybrid power system.