YSPKK Series High-Voltage Three-Phase Asynchronous Motors
YSPKK series high-voltage three-phase asynchronous motors are specially designed squirrel cage variable frequency motors with closed box structure and independent air-to-air cooling system. Developed to match high-voltage frequency converters, this series is optimized for variable speed working conditions and fully complies with IEC international standards. Different from conventional fixed-speed high voltage motors, YSPKK motors adopt dedicated electromagnetic and thermal design to restrain extra harmonic loss, vibration and heat generated during variable-frequency operation. It supports wide-range speed regulation and stable continuous operation under S1 duty, making it an ideal choice for energy-saving transformation of fans, water pumps and compressors in heavy industries. The closed cooling structure isolates internal air circulation from the external environment, so the motor can run reliably in dusty, humid and slightly corrosive workshops.
Core Technical Parameters
| Technical Item | Specification |
|---|---|
| Series | YSPKK Series High-Voltage Three-Phase Asynchronous Motors |
| Rated Voltage | 3kV / 6kV / 6.6kV / 10kV / 11kV |
| Rated Power Range | 220kW ~ 12500kW |
| Speed Regulation Range | 5–50Hz constant torque; 50–67Hz constant power |
| Insulation Class | Class F, temperature rise assessed at Class B |
| Protection Grade | IP44 / IP54 / IP55 |
| Cooling Method | IC616 Air-to-air cooling with independent blower |
| Rotor Type | Squirrel cage, copper bar or cast aluminum |
| Mounting Form | IMB3 Horizontal |
| Frequency | 50Hz / 60Hz optional |
The electromagnetic design of YSPKK series is optimized at multiple frequency points by finite element simulation to suppress harmonic excitation caused by inverter power supply. The stator core is laminated with high-performance low-loss silicon steel sheets to reduce iron loss and stray loss during variable speed operation. Stator windings use high-quality electromagnetic wire and go through VPI vacuum pressure impregnation treatment with anti-corona protection. The solidified winding structure improves dielectric strength and thermal stability, resisting voltage spike impact output from frequency converters. The squirrel cage rotor is available in two options. Copper bar rotor version delivers stronger mechanical strength and better anti-fatigue performance, suitable for frequent speed adjustment and fluctuating load. Each rotor undergoes high-precision dynamic balance calibration to control vibration and noise within strict limits across the whole speed range.
The motor adopts rigid welded steel plate box frame with high structural stiffness, which can effectively reduce resonance risk under variable frequency working conditions. The core feature of YSPKK is IC616 closed air-to-air cooling system equipped with independent external blower. Two fully separated air loops are arranged inside the motor. The internal hot air circulates inside the closed frame and exchanges heat with clean external air through the top-mounted air-to-air heat exchanger. The independent blower guarantees stable cooling air volume even at low rotating speed of the main motor, solving the problem of insufficient self-fan cooling when running at low frequency. This cooling structure keeps dust, moisture and corrosive gas out of the motor chamber, protecting windings and iron core from contamination.
The bearing system is configurable according to power and speed. Medium-power models use heavy-duty rolling bearings, while large-power units adopt sliding bearings. PT100 temperature sensors can be embedded in stator windings and bearings as optional configuration, transmitting real-time temperature data to the central control system for over-temperature monitoring and early warning. Special sealing structure is applied for bearing chamber to prevent oil leakage and dust ingress. The motor can be customized for low-temperature environment, anti-corrosion coating and reinforced bearing to meet different site requirements.
YSPKK series variable frequency high voltage motors are widely used for energy-saving reconstruction projects in mining, cement, chemical, power and metallurgy industries. Typical applications include large induced draft fans, circulating water pumps, compressors and belt conveyors. Variable speed regulation can greatly cut power consumption under partial load conditions and bring remarkable energy-saving benefits. Every motor will complete a full set of factory tests before delivery, including insulation test, no-load test, variable frequency running test, vibration and noise inspection. With excellent variable frequency adaptability, stable temperature rise and convenient maintenance, YSPKK series high-voltage asynchronous motors provide reliable energy-saving drive solutions for global industrial variable speed projects.
