| 摘要 |
PURPOSE:To provide a brake controller for an inverter with less irregularity of a braking distance due to shortage of a braking time by providing a circuit which changes the combination of ON states of switching elements upon reception of a brake command signal into the form which is before a brake command signal. CONSTITUTION:A clock signal proportional to the frequency of the output waveform of an inverter outputted from an oscillator is converted through a base signal generator 6 and a brake controller 7 to a base signal to transistors Tr11-Tr23 forming a 3-phase transistor inverter 1. When a brake command S1 is outputted, an operation mode is switched to a brake mode via a flip-flop 8, a signal to be inputted to the transistor Tr11 in the operation mode is inputted to the transistor Tr21, and a signal to be inputted to the Tr21 is inputted to the Tr11 (similarly between the Tr12 and Tr22, and between the Tr13 and Tr23). Thus, the combination of ON and OFF of the Tr11-Tr23 is differed from the form which is before the brake command signal, thereby forming a DC braking circuit. |
