| 摘要 |
<p>PURPOSE:To prevent main transformers from being multi-split, by applying specified phase difference to a carrier wave used for controlling the pulse width modulation of a PWM converter on each car body for composing a train. CONSTITUTION:The driving car bodies of (m) units composing a train are equally divided into K groups. Within each group, a unit converter is controlled by the same PWM control signal. Accordingly, PWM controllers consisting of modulated wave signal generating sections, carrier wave generating sections, and comparison sections for comparing a modulated wave with a carrier wave can be used in common. Between the groups, each modulation signal of the modulated wave signal generating sections are of the same phase, but each carrier wave signal of the carrier wave signal generating sections is shifted positionally and mutually by specified phase. As a result, the secondary windings of main transformers T1-Tm at respective power source units can be prevented from being multi-split, and equivalent jamming current can be reduced.</p> |
