Electric current detector of pole-changing die induction motor

摘要

(57) Abstract Objective When operating the pole-changing die induction motor in the high-speed pole,When operational electric current and operating in the low-speed pole, operational electric current equalityTry to be able to detect making use of the converter. Constitution motapon which adopts the pole-changing die induction motorIn pu and the like, in order to detect overload and nul operation, it is to be,In order to make operational electric current the Ammeter specify, electricity for low-speed polar operationSource belt LR1, LS1, LT1 and power source belt LR for high-speed polar operation2, LS2 and LT2 are made to penetrate completely to identical converter 3. It is denseDensely being, as for frequency of power source belt complete penetration of converter 3, power source for low-speed polar operationFrequency of complete penetration of belt LR1, LS1 and LT1 and electricity for high-speed polar operationRatio of frequency of complete penetration of source belt LR2, LS2 and LT2, low speed extremelyWhen so operating, when configuration electric current and operating in the high-speed pole, configuration electricityTo make the integer ratio which is closest to the inverse number of ratio of flow, low-speed side and high-speed sideBe able to detect overload operation and the like almost with identical converter outputIt makes the ru way.