| 摘要 |
PURPOSE:To provide a converter circuit in which the surge current prevention resistors and the regenerative power consumption resistors can be decreased in number and the number of types thereof. CONSTITUTION:When an AC three-phase voltage is thrown in, a magnet contactor A1 is opened and the series circuit of resistors R1 and R2 serves as a surge current prevention resistors thus charging a capacitor C. Upon elapse of time for settling the surge current, a delay circuit A2 closes the magnet contactor A1. On the other hand, an overvoltage detecting circuit B1 turns a switching element B2 ON upon detection of an overvoltage thus bringing about a state where the parallel circuit of resistors R1, R2 is connected in parallel with the capacitor C. Consequently, the excessively regenerated power from a servo motor M is consumed through the parallel circuit of the resistors R1 and R2 thus preventing the voltage rise. This circuit realizes reduction in size and enhancement of reliability. |
