Analysis Of Thermal Management And Heat Dissipation Technology Of Hairpin Flat Wire Motors

With the rapid development of new energy vehicles, power tools and intelligent manufacturing equipment, the requirements for motor performance are constantly increasing. Among them, hairpin flat wire motors (Hairpin Motor) have gradually replaced traditional round wire motors with high power density, high efficiency and good mechanical stability, becoming the mainstream choice for high-performance drive systems. However, with the increase in motor power, thermal management and heat dissipation issues have become particularly critical.

Why do hairpin flat wire motors need more thermal management?

The hairpin flat wire motor uses enameled copper wire with a rectangular cross-section, and forms the stator winding by laser welding or resistance welding. Compared with traditional round wire motors, it has a higher slot fill rate and more copper wire per unit volume, which means more current and more heat. In addition, the stator core and windings under high-speed operation are prone to eddy current and hysteresis loss, further increasing the heat load. If the heat cannot be effectively exported in time, it will lead to insulation aging, reduced efficiency and even motor burning.

Key technologies for thermal management

1. Thermal conduction design of stator windings

During the design stage, the thermal conduction path of the winding must be fully considered. By optimizing the potting material in the slot (such as thermally conductive resin) and improving the contact efficiency between the coil and the core, the thermal resistance of the winding can be effectively reduced and the heat dissipation efficiency can be improved.

2. Selection and distribution of cooling medium

Common cooling methods include water cooling, oil cooling and air cooling. Among them, the water cooling system is the first choice for high-performance hairpin flat wire motors due to its high heat capacity and good thermal conductivity. By setting cooling water channels or cooling jackets in the stator housing, it is ensured that the coolant is in full contact with the heating area to achieve rapid heat dissipation.

3. Thermal simulation-assisted optimization design

In the early stage of motor development, the thermal distribution of the stator, rotor, bearing and housing is predicted by thermal simulation software, which can detect high-temperature areas in advance and optimize the structure and material layout. This not only improves design efficiency, but also reduces the risk of thermal runaway in the later stage.

4. Integration of intelligent temperature control system

With the development of intelligent manufacturing, more and more hairpin motors are equipped with temperature sensors and control modules, which can monitor the winding and core temperature in real time, dynamically adjust the workload or enable the cooling system to ensure that the motor operates within a safe temperature range.

Summary

Although the hairpin flat wire motor has excellent electrical performance, its high power density also puts higher requirements on the thermal management system. Through reasonable structural design, cooling medium configuration and application of intelligent temperature control technology, the motor temperature rise can be effectively reduced, and the service life and system stability can be improved. In the future, with the continuous advancement of materials and process technology, the heat dissipation efficiency of hairpin motors will be further improved, helping various high-end equipment to move towards higher performance.