Magnetic control thyristor chopper equipment for battery vehicle

The following three major advantages were observed by adopting a magnetic phase shifter for gate control of a thyristor. 1) A single magnetic phase shifter can compare and amplify multiple signals in an insulated status. 2) At the same time, simplified current detection greatly reduces the number of parts required. 3) It is barely susceptible to the influences of noise. These facts imply that a magnetic phase shifter constitutes a highly reliable and low-cost control device. Especially, using this as a control unit for a chopper offers a substantial advantage with respect to the antinoise margin. By utilizing a balanced half-wave type magnetic phase shifter (capable of operating with a dc power source by combining with a switching transistor), we have developed a gate controller that is free from the influences of noise and allows control of current duties ranging from a minimum value to 100 percent maximum with a greatly simplified circuit.