| 摘要 |
<p>The invention relates to a method and installation meant to verify the dielectric stability of the preformed coil insulation of the average voltage asynchronous motors relative to the ground. According to the invention, in order to ensure the impulse wave imposed by standards, the method consists in compensating said deficiency, by connecting a supplementary capacitor in parallel with the testing coil, having a well-established value, so that the following relation defining the wave shape of the test voltage u= kU (e-14,493.10^3 t - e - 2,532.10^6 t), where k is a quantity depending on the impulse generator components, and U is the charging voltage of the impulse capacitor of the generator, should be satisfied. According to the invention, the installation comprises a system for charging, from a high voltage source, a capacitor consisting of diode (DR), a limit resistor (RL1) and a spark gap (E) for discharging the previously charged capacitor and a load consisting of a resistor (R2), a serial resistor (R3) and an additional capacitor (Cs) parallelly connected with the capacitance of coil (Cb), the wave shape being recorded by means of a resistive voltage divider (Ro).</p> |
