GHYT Series High Voltage AC Motor Liquid Soft Starter
GHYT series high voltage AC motor liquid soft starter is suitable for soft starting of large and medium synchronous or asynchronous squirrel cage and wound rotor motors with rated voltage of 3~10kV. Under static standby conditions, its performance characteristics are equivalent to those of a conventional reactor starter. Under dynamic starting conditions, it achieves stepless continuous starting by utilizing the variable-resistance characteristics of the liquid electrolyte medium. The entire motor starting process — including current, torque, and time parameters — can be accurately predicted, adjusted, and controlled.
The starter operates on the principle of adjusting the electrode gap within a liquid electrolyte tank to achieve continuous variation of the stator circuit resistance during motor startup. As the motor accelerates, the control system automatically reduces the liquid resistance by adjusting the electrode position, allowing a smooth, stepless transition from starting current to rated current without torque pulsations or mechanical shock.
Technical Specifications
| Item | Specification |
|---|---|
| Rated Voltage | 3kV / 6kV / 10kV |
| Rated Frequency | 50Hz / 60Hz |
| Rated Power Range | 200kW – 30,000kW (customizable) |
| Starting Current | 1.5 – 3.5 times rated current (adjustable) |
| Starting Time | 5 – 60 seconds (adjustable per application) |
| Starting Torque | 30% – 80% of rated torque (adjustable) |
| Number of Consecutive Starts | 3–5 times at rated conditions |
| Liquid Medium | Electrolyte solution (Na₂CO₃ or customized) |
| Electrode Material | Stainless steel with anti-corrosion treatment |
| Cooling Method | Natural cooling / Forced air cooling |
| Degree of Protection | IP30 / IP42 (cabinet) |
| Control Interface | PLC + touch screen (Chinese/English) |
| Communication Protocols | RS485 / Modbus RTU (optional) |
| Ambient Temperature | 0°C to +40°C |
| Ambient Humidity | ≤ 90% (non-condensing) |
| Standards | GB/T 12668, IEC 60947-4-2 |
Key Features
- Liquid Resistance Starting Principle: Utilizes the variable-resistance characteristics of electrolyte solution to achieve stepless continuous starting — as the motor accelerates, electrode gap is automatically adjusted to reduce starting resistance, providing a smooth transition from start to full-speed operation without current or torque pulsations
- Extreme Power Capability: Suitable for very large motors up to 30MW, significantly exceeding the power range of solid-state thyristor starters, making it the preferred solution for large synchronous motors, ball mill drives, and heavy industrial applications
- Low Starting Current: Limits starting current to as low as 1.5–2.5 times rated current, far below DOL starting (6–8 times rated current) and solid-state starter typical ranges (3–4 times rated current), minimizing voltage dips on the power supply network and reducing thermal stress on motor windings
- Smooth Stepless Acceleration: Unlike stepped resistance starters or autotransformer starters, the liquid variable resistance provides continuous, stepless acceleration eliminating torque transients at switching points — critical for applications sensitive to mechanical shock
- Predictable and Adjustable Starting Parameters: Starting current, torque, and acceleration time can be precisely preset and adjusted through the control system, allowing optimization for different load types and site conditions
- Multi-Start Capability: Designed for 3–5 consecutive starts at rated conditions without requiring cooling intervals, making it suitable for applications requiring frequent starting or restarting sequences
- Low Initial Cost for High Power Ratings: For large motor applications above 5MW, the liquid soft starter offers significantly lower capital cost compared to solid-state variable frequency drives (VFDs) of equivalent power rating, with comparable starting performance benefits
- Mature and Proven Technology: Liquid resistance starting is a well-established technology with decades of field-proven performance in the most demanding heavy industrial applications globally
APPLICATIONS
- Large synchronous and asynchronous motors in cement plants — ball mills, rotary kilns, and crushers
- High-power fans and compressors in steel and mining industries
- Large pumps — water supply, drainage, and irrigation (up to 10MW+)
- Mine hoists, conveyors, and material handling systems
- Power plant auxiliary motors — ID fans, FD fans, coal mills, and feed pumps
- Petrochemical and refinery large motor drives
- Compressors and blowers in chemical processing plants