Connection of inverters to a weak grid

Abstract

Connection of an inverter to export power to the mains for a stiff supply is well understood. This paper examines the dynamics of power export to a weak grid. In this case the local bus angle changes for changes in export power which interferes with the process of synthesizing the inverter voltage. The paper shows the results of linearised analysis of a voltage source converter with the phase of the terminal voltage determined from Fourier coefficients. The dynamics of a simple distribution system are analyzed with the inverter connection and the predicted performance of an inverter compared with the experimental 500 W single phase inverter.