Chapter 9 - Adjoint network theory to analyse the power converters with respect to their line-side behaviour

Abstract

This chapter presents a straightforward approach for the sensitivity analysis of the line-side connected converters with respect to the variation of their parameters. The sensitivity analysis is carried out based on the adjoint network theory. This allows studying the variation of an electrical quantity with respect to the perturbation of any circuit parameter, considering only one circuit besides the one assigned. As the control of a converter plays an important role in the propagation of the harmonics in the circuit, it is necessary to implement a detailed model of the controller too. Starting from the requirements of the digital controller, an analogue circuit that is able to represent the behavior of the controller is synthesized. Substituting the controller with the virtual circuit, an analogue network, representing the power converter and its control, is obtained. This homogenous model allows a rigorous and straightforward sensitivity analysis. This straightforward approach does not neglect anything of both the physical system and the digital controller. Also, with this approach it is easy to evaluate the problems of the use of the line-connected converter related to the propagation of harmonics in an industrial plant.