Gas compressor

A gas compressor including a compression mechanism that compresses a sucked working fluid, a separator tank that introduces lubricating oil to be supplied to the compression mechanism and a mixed fluid of the working fluid and the lubricating oil discharged from the compression mechanism and separates the lubricating oil from the compressed working fluid, an oil cooler that introduces and cools the lubricating oil separated in the separator tank, an oil circulation path that supplies the lubricating oil cooled by the oil cooler to the compression mechanism, and a motor that drives the compression mechanism and is isolated from the oil circulation path, the gas compressor comprising:

• a suction temperature sensor that detects a suction temperature of the working fluid sucked into the compression mechanism;
• at least one of a discharge pressure sensor that detects a discharge pressure of the working fluid compressed by the compression mechanism or a rotation speed sensor that detects a rotation speed of the motor, the discharge pressure or the rotation speed of the motor being detected by the comprised discharge pressure sensor or rotation speed sensor;
• a power sensor that detects input power of the motor;
• and
• a lubricating oil state estimation unit that calculates the rotation speed or the discharge pressure that is not detected by using values of the input power detected by the power sensor and the discharge pressure or rotation speed detected by the comprised discharge pressure sensor or rotation speed sensor, and estimates a temperature of the lubricating oil based on the detected suction temperature, the detected discharge pressure or rotation speed of the motor, and the calculated rotation speed of the motor or discharge pressure, wherein
• the lubricating oil state estimation unit estimates a deterioration state of the lubricating oil based on the estimated temperature of the lubricating oil.