Cooling Water Circuit Principle of YKS Series High-Voltage Air-to-Water Cooled Motor (IC81W)

1. Cooling Classification

YKS: Totally enclosed squirrel-cage HV motor with top-mounted Air-to-Water heat exchanger, cooling type IC81W.
Two fully separated independent loops without medium mixing:

1. Primary closed air loop inside motor (heat absorption medium)
2. Secondary circulating cooling water loop (heat rejection medium)

2. Dual Circulation Working Flow

Primary Closed Internal Air Circuit

1. Losses of stator & rotor heat up internal air;
2. Built-in centrifugal fans on rotor shaft circulate hot air synchronously with motor speed;
3. Hot air flows through stator radial ducts & winding end regions into the top air-water heat exchanger shell;
4. Heat transfers from hot air to cooling water inside finned tubes; cooled air circulates back to motor interior.
5. Totally sealed housing, IP54/IP55 protection, dust & moisture isolated from windings.

Secondary Cooling Water Circuit (External Circulation System)

Cooling water tank → shut-off valve → Y-type water filter → pressure regulating valve → heat exchanger water inlet (bottom)
→ stainless steel finned tubes absorb heat → warm water outlet (top) → circulating water pump → cooling tower / plate heat exchanger
→ cooled water flows back to tank for continuous cycle.

3. Key Technical Parameters

• Max inlet water temperature: ≤33℃; outlet ≤43℃, temperature difference 8~10K
• Inlet water pressure: 0.1~0.3 MPa
• Recommended medium: softened / demineralized water to avoid limescale blockage

4. Main Components of Water Cooling System

1. Air-to-water heat exchanger (motor integrated): heat exchange core with drain & air vent valves
2. Water treatment accessories: filter, pressure stabilizer, isolation valves
3. Circulation pump: provides flow power
4. External heat rejection unit: cooling tower
5. Protection sensors: flow switch, temperature transmitter, water leakage detector
6. Heat tracing & insulation for anti-freezing in cold regions