Hisense innovatively applies aerospace ceramic bearing technology on refrigerant centrifugal compressors, achieving liquid suspension operation of ceramic bearing balls. Bearing friction power consumption is lower than 1kW , significantly reducing power consumption compared to conventional bearings which contributes to high energy efficiency of chillers.

The combination of multiple innovative technologies has created Hisense's ultra-efficient centrifugal compressor.

The oil free compressor is equipped with aerospace-grade and high-precision ceramic bearings, achieving high loading capacity, low power consumption, and long lifespan.

We use multi-physical coupling design in the unit system. Taking velocity field,temp field,pressure field and stress field into account together, Hi-Levi S Series can realize both high efficiency and high stability.

Hisense designed a new type of gas seal ring based on the small working gaps in ceramic bearings to reduce internal leakage losses.

Advantages compared to traditional magnetic levitation chiller units:

● Reducing the sealing gap ＞ 70%

● Improving pneumatic efficiency ＞3%

Why Hi-Levi S Series chiller units are more efficient?

Magnetic levitation units have large gap between the shaft and the bearing, so that the leakage of compressed gas go into the motor and leads to the lower efficiency.

High-Performance Vector Control Technology

● Adjust inverter output voltage-frequency ratio based on real-time motor load rate

● Precise control, ±0.1Hz frequency control

Complex Vector PI Controller Design

● Software algorithms construct complex vector controllers

● Neutralize complex vector poles in motor models

● Eliminate dq-axis current coupling

Advantages of Variable Frequency Drive Technology

● Higher Dynamic performance of cuurent in high-speed weak magnetic regionsDynamic performance of cuurent in high-speed weak magnetic regions

● Suppressing harmonic components maximally

● Higher Efficiency of the load motor

● Higher Whole system efficiency

● Low starting current, less impact to power system

Entire Operation Cycle of Lubrication: Based on full working cycle liquid supply control logic and highly integrated liquid supply modules, our unit achieves automatic scheduling of two bearing lubrication methods: Liquid supply based on system pressure difference and pump forced liquid supply.

No Flashing Gas: Hisense innovatively adopts secondary subcooling technology for bearing liquid supply, ensuring no flashing gas during the period of refrigerant lubrication.

Double Refrigerant Pumps Backup: Balance control of 2 pumps ensures stable liquid supply to the bearings with online switching during operating time, which prolongs the service life of the refrigerant pump.

No Worry of Power Failure: In the event of a sudden power failure, the system pressure difference can continue to supply liquid to lubricate the bearings until the shaft stops rotating.