Analysis of droop controlled paralled aircraft generators through common DC bus

Abstract

With the increase in electrical loads and the shift from hydraulic and pneumatic to electrical systems, such as in the Boeing 787s no-bleed system architecture, the concept of the More Electric Aircraft is gaining popularity. The no-bleed system architecture brings with it also the introduction of a ±270V(540V) DC power system. This paper analyses a 540V DC aircraft electrical power system using two turbine-driven synchronous generators, which are controlled through their excitation field windings. The generators are paralleled through a common DC bus. Load sharing between the two generators is achieved through a droop control scheme. The analysis carried out in this paper encompasses changes in load power and operating frequency of the generators. This is carried out using the Simscape simulation toolbox in MATLAB/Simulink.