MODELING OF CONVERTER TRANSFORMERS USING FREQUENCY-DOMAIN TERMINAL IMPEDANCE MEASUREMENTS

HVDC converter stations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. In order to calculate and predict the RF EM noise produced by the valve ignition of a converter station, it is essential to develop accurate models of station equipment over a broad frequency range. Models of all station equipment can be characterized by frequency dependent impedances. The paper describes the frequency dependent node-to-node impedance function (NIF) models of power system equipment based on systematic broad frequency range (50 Hz to 1 MHz) external driving point impedance measurements, sponsored by the Electric Power Research Institute (EPRI). The regular structure, high accuracy, and virtually unlimited frequency range are important features of the NIF model. Examples of NIF model application in converter station RF EM noise calculations are presented.