| 摘要 |
PURPOSE:To obtain the dv/dt resistance value of a thyristor with high speed and accuracy by a method wherein a simple circuit is added to a circuit to be measured originally so that the arrived voltage value of an interative inclined voltage is made to increase from the zero potential as time elapses. CONSTITUTION:Circuits other than one enclosed by a broken line are those already known. A rectified voltage is added between the collector and emitter of a transistor 24 via a resistor and the output of the transistor is stabilized to stabilize the part between the base and earth by a constant-voltage diode 25. A capacitor 26 and a switch 19 are connected together in parallel between the base and earth of the transistor 24. When the switch 19 is closed, the base voltage becomes zero. When it is opened, the voltage gradually rises to the Zener voltage because of the time constants of the capacitor 26 and resistor 27. Accordingly, the output of a lamp function generator 15 also gradually rises. By so doing, measurement can be taken without malfunction even if a number of thyristors are to be measured by means of an electromagnetic switch, etc. |
