Current and Voltage Wave Shape of Mercury Arc Rectifiers

This paper gives data on the voltage and current wave shape of mercury arc rectifiers on both the d-c and a-c side. The values of the harmonics at light load are considered first and the modifications of the harmonics under load due to impedance then are studied. The results of tests on rectifiers are given and are in reasonable agreement with the theoretical values which, for convenience in use, are plotted in the form of curves. The relation between the harmonics in rectifiers with different transformer connections is shown and consideration also is given to modifications introduced when the a-c voltage contains harmonics or has a phase unbalance. A brief discussion is given of some methods of modifying the harmonic voltages in this type of apparatus.