As the choice of centrifugal air compressor motor voltage, 380V and 10kV solutions are widely used in the industry. However, the impact of the two solutions on the unit is obvious, including: the impact of the use of high-voltage 10kV and 380V voltage on the initial investment and operating costs of the unit, as well as some invisible impacts caused by the use of different solutions, which have exceeded the consideration scope of compressed gas industry personnel, but are issues that must be considered by power distribution professionals.
First, the conclusion: kapa screw air compressor factory recommends that high-power centrifugal air compressor motors use high-voltage 10kV (grid voltage) motors, rather than low-voltage 380V motors. The operation scheme has the following advantages:
1: Greatly reduce the motor operating current, enhance the operating safety and reliability, and reduce the equipment failure rate. The motor power of a 100m³/min centrifugal air compressor is about 600kW each. If 380V power supply is used, the full load current is 1059A each; if 10kV power supply is used, the full load current is 40.2A each. The low voltage current is 26.3 times the high voltage current. The use of high voltage motors will greatly reduce the maximum starting current of the unit. For high-power motors, the impact of high voltage starting on the power grid is much smaller than that of low voltage starting. The starting current of a general motor is 6-7 times the rated current. The impact and harm of high current on the power grid are greater, so soft start or variable frequency starting is generally required. The safety and reliability of its operation is enhanced, and the failure rate is reduced.
2: The built equipment room can be used (i.e.: reduce the space occupied by the equipment), and the total power distribution room can be considered as a whole to achieve systematization, standardization and rationalization of power distribution management.
3: The rated current of high-voltage motors is small, and the cross-sectional area of cables is small; while the rated current of low-voltage motors above 250KW is large, and multiple large cables need to be used in parallel, and the wiring is inconvenient, and it is easy to cause heating and accidents due to the large contact resistance of the cable head.
4: Compared with low voltage, if high-voltage motors are used, operation, maintenance, and equipment repair are more convenient and safer. Due to the large rated current of low-voltage motors, the heat generated by components in the drawers of low-voltage distribution cabinets is large, and starting, cables and other components and equipment are added. Relatively speaking, the probability of failure is much higher when using low voltage.
kapa screw air compressor factory recommends that high voltage should be used as much as possible for motors above 250KW; if there is no choice, try to make up for it during electrical design.
