Propulsion and Control Considerations for an Intermediate Capacity Transit System

An Intermediate Capacity Transit System (ICTS) has been developed by the Urban Transportation Development Corporation (UTDC) under contract with the Ontario Provincial Government. A full scale experimental system has been undergoing tests at the UTDC Transit Development Centre in Kingston, Ontario, and the system is now in the production design phase. The operational requirements for the ICTS have lead to the adoption of linear induction motor (LIM) propulsion for the ICTS vehicles. The LIM concept, in addition to providing the primary propulsion for the vehicle, also provides a highly effective braking mechanism. The dynamic LIM braking may be used in a regenerative mode, enabling energy recovered during braking to be fed back into the power distribution system. To achieve the required service levels, the ICTS vehicles are designed for fully automatic operation without drivers or attendants. The vehicles are controlled by a wayside computer system which supplies commands to the vehicle on-board control equipment through an inductive loop communication system. The vehicle translates these commands into vehicle operations. The control system adopted for ICTS is unusual amongst rail vehicle control systems in utilizing a moving block principle to achieve the required system capacity.