Compressor protective device for refrigerator and method of protecting refrigerator compressor

A compressor protective device for a refrigerator including a voltage sensor detecting a voltage applied to a compressor through a shunt resistor; a voltage amplifier amplifying a voltage signal from the voltage sensor; a voltage converter converting the voltage signal, amplified by the voltage amplifier, into a voltage of absolute value; and a controller producing a high signal or low signal in response to the voltage signal out of the voltage converter to control a turn-on or turn-off operation of the compressor, a method of protecting a compressor for a refrigerator having a voltage sensor and a controller, including the steps of determining whether or not the compressor is turned on and an error flag is set; it the error flag is set, determining whether or not an output voltage of the voltage sensor is higher than a reference voltage; if the voltage of the voltage sensor is higher than the reference voltage, determining that an overvoltage is applied to the compressor, and increasing error data in the controller by one to determine if the increased error data is higher than a given value; and if the increased error data is higher than the value, stopping the operation of the compressor.