Error Reduction of The Low-Frequency Sampling Method for Measuring The Current, Voltage And Power of a Cage Induction Motor

The low-frequency sampling method consists in sampling a periodic signals (in this case sinusoidal) at intervals much greater than its period. Nevertheless, it is possible to obtain all relevant electrical information such as active, reactive power and rms values. The low-frequency sampling method allows a significant reduction of computing power and, consequently, enables on-line power and RMS values calculation by a simple PLC microcontroller without overloading it and enabling its normal operation as a controller. The article presents a way of reducing measurement error of the low-frequency sampling method.