THE USE OF SWITCHING-FUNCTIONS AND WALSH-SERIES TO CALCULATE WAVE-FORM DISTORTION IN THYRISTOR CONTROLLED COMPENSATED POWER CIRCUITS

A new model based on Walsh series for assessing the steady state opera tion of three phase Thyristor Controlled Reactors (TCRs) is presented in this paper. The model represents the TCR as an admittance matrix wh ich interfaces easily with other power plant components in the network . Clearly, the admittance matrix representation is not confined to Wal sh domain but rather it is valid for any orthogonal approximation of f unctions having the operational properties used in this paper. However , the switching functions which characterise the operation of TCRs are better represented by Walsh series and they have been used in this pa per. This is a new development in power systems analysis. Other orthog onal series expansions such as Fourier series and Hartley series have been used elsewhere. Walsh transform possesses the important operation al properties of the Product, Coefficient and Integration matrices. Th e relevant aspects of the interaction between the TCR and the electric network are analysed. A three phase TCR and a transmission network re presented by a Thevenin equivalent are used for this purpose.