Method for controlling electric compressor

Abstract

Disclosed is a method of controlling an electric compressor. The method includes: (I) starting the electric compressor by applying an electric power to an air conditioner; (II) determining, by an inverter, whether the electric compressor is started normally; and normally driving the electric compressor when the electric compressor starts normally in the step (II) and determining again whether the electric compressor starts normally by restarting the electric compressor. Therefore, abnormal operation such as malfunction, short, and overheating of the electric compressor is detected in the early starting stage to determine restarting and failure of starting the electric compressor so that reliability of the electric compressor may be enhanced.

1 . A method of controlling an electric compressor comprising:
 (I) starting the electric compressor by applying an electric power to an air conditioner;   (II) determining, by an inverter, whether the electric compressor is started normally; and   (III) normally driving the electric compressor when the electric compressor starts normally in the step (II) and determining again whether the electric compressor starts normally by restarting the electric compressor when the electric compressor does not start normally.   
     
     
         2 . The method of  claim 1 , wherein, after the step (III), the electric compressor is driven normally when the electric compressor starts normally and the step (III) is repeated by a preset times when the electric compressor does not start normally. 
     
     
         3 . The method of  claim 2 , wherein, when the electric compressor does not starts normally even after repeating the step (III) by the preset times, failure of starting of the electric compressor is determined and an error message is outputted. 
     
     
         4 . The method of  claim 2 , wherein a preset stand-by time for restarting of the electric compressor is provided when the step (III) is repeated. 
     
     
         5 . The method of  claim 2 , wherein a starting current when the step (III) is repeated is within Max ±25% of a driving current. 
     
     
         6 . An electric compressor controlling method of detecting abnormal operation of an inverter or a driving motor before starting the electric compressor, comprising:
 (I) applying an electric power to an air conditioner;   (II) detecting currents of three phases by a sensor by applying a minute current to the driving motor of the electric compressor; and   (III) determining the abnormal operation of the inverter or the driving motor using sum of the three phase currents (Ui+Vi+Wi).   
     
     
         7 . The electric compressor controlling method of  claim 6 , wherein the electric compressor is normally started or driven when the sum of the three phase currents is 0 (zero) or within an error range and it is determined that the inverter or the driving motor is malfunctioned and an error message is outputted when the sum of the three phase currents is not 0 (zero) or out of the error range. 
     
     
         8 . The electric compressor controlling method of  claim 6 , wherein the step (III) is carried out within 1 (one) second. 
     
     
         9 . The electric compressor controlling method of  claim 8 , wherein the sensor comprises a current sensor or a resistive sensor. 
     
     
         10 . An electric compressor controlling method of detecting abnormal operation of an inverter or a driving motor of an electric compressor before starting the electric compressor, comprising:
 (I) applying an electric power to an air conditioner;   (II) detecting two of three phase currents (Ui, Vi, and Wi) by a sensor by applying a minute current to the driving motor of the electric compressor;   (III) calculating remaining one phase current from the two phase currents; and   (IV) determining whether the inverter or the driving motor is operated abnormally by comparing the three phase currents (Ui, Vi, and Wi) with a reference current.   
     
     
         11 . The electric compressor controlling method of  claim 10 , wherein, in the step (III), the remaining one phase current is obtained from the two phase currents from the fact that sum of the three phase currents (Ui+Vi+Wi) is 0 (zero). 
     
     
         12 . The electric compressor controlling method of  claim 11 , wherein, after the step (IV), the electric compressor is normally started or driven when the three phase currents (Ui+Vi+Wi) are within an error range of the reference current and the inverter or the driving motor is determined as being malfunctioned and an error message is outputted when the three phase currents (Ui+Vi+Wi) are out of the error range of the reference current. 
     
     
         13 . The electric compressor controlling method of  claim 10 , wherein the step (IV) is carried out within 1 (one) second. 
     
     
         14 . The electric compressor controlling method of  claim 13 , wherein the sensor comprises a current sensor or a resistive sensor.