METHOD OF CONTROLLING ELECTRIC ROLLING STOCK CHOPPER

摘要

PURPOSE:To allow smooth control along a current limit value pattern, by controlling the frequency of a chopper while comparing the current value of a motor of an electric rolling stock with current limit value pattern voltage value as feedback quantity. CONSTITUTION:When a power source of a control circuit is in ON by the operation of drivers, a CPU 51 reads commands from a master controller 55 through an input port 49, and performs the sequence control of a main circuit, such as, the change- over of forward and backing, power travelling, the arrangement of the control circuit, etc. through an output port 61 in response to the commands of the master controller 55. When the arrangement of the main circuit finishes, the flow rate of a chopper is computed on the basis of pattern voltage values, motor current values and voltage values and filter condenser voltage values continuously read through an input port 48, thus controlling motor current. In this case, the frequency of the chopper is slowly increase up to a fixed frequency while comparing the relaxation pattern of current limit values and motor current when starting.