| 摘要 |
<p>PURPOSE:To reduce the wear of a brake shoe and to increase a regenerative brake force by reducing a supplementary brake amount when two groups of motors are switched between series and parallel. CONSTITUTION:If the value of a shunt field current If arrives at the predetermined value when two groups of motor are controlled between parallel and series, a contactor S is closed. Then contactors P, G are opened, resistors R1, R2 are sequentially shortcircuited to complete a switching control. A signal SG of a parallel brake end by the current If is supplied to a correction signal generator 6. While this signal SG is supplied to the generator 6, a pneumatic brake for supplying insufficient transient regenerative brake force is suppressed at parallel/series switching time occurred normally as a correcting brake amount to reduce the wear of a brake shoe.</p> |
