The representation of impedances on the resistance network analyser

Owing to the high cost of a.c. network analysers for power-system studies, attempts are often made to solve problems involving resistance, reactance and power factor on d.c. analysers equipped only with resistors. It is then necessary either to ignore phase displacements and accept errors in the solution or to adopt artifices to obtain greater accuracy¿and therefore to introduce increased complexity. A method has been developed whereby a conventional network analyser equipped only with resistors is energized from a 2-phase a.c. supply and phase displacements due to reactances are obtained by injecting voltages which are constant in direction. The method is applicable to either load flow or fault studies if transient effects are absent. The additional equipment required is inexpensive when an orthodox resistance analyser is available, and the accuracy of the solution is high