Evolution of microprocessor control [for railway applications]

Microprocessor control of traction equipment has been around for over 10 years. The first systems used single 8 bit processors carrying out relatively simple tasks but over the years this has grown into multiprocessor systems providing many and various features. With the advent of Gate Turn Off (GTO) thyristor technology, the AC motor, the AC motor is now replacing the conventional DC motor and this requires even more complex and faster processors for full control. The author describes the history of microprocessor control, highlighting some of the features provided and then explain current and future developments that will be found on the next generation of vehicles