The invention discloses a high voltage frequency converter input current detection method and a novel high voltage frequency converter which is realized through the method. The input current detection method comprises steps of replacing two short connection wires between an A phase coil winding and a C phase coil winding and a neutral point with reinforcement insulation cables; low voltage current inductors sleeve the cables, which enables the low voltage current inductors to be connected to a master control cabinet; two low voltage current inductors respectively measure A phase current and C phase current on a primary side of a phase displacement transformer in order to realize the detection on the input current. The invention can accurately and effectively detect the input current of the high voltage frequency converter, satisfies the reinforcement insulation requirement between the low voltage current inductors and the cables, greatly saves the length of the cable for enhancing the insulation, and reduces the product cost for the high voltage frequency converter.