Toshiba has developed a new magnetic material that greatly improves motor efficiency at the lowest cost and has the potential to significantly reduce power consumption. The company said this material is suitable for train drive systems, automobiles, robots and other high-reliability applications.
This new material can be used as a slot wedge for motors, especially in large and medium-sized induction motors, which can greatly improve the energy conversion efficiency of the motor. Toshiba said the installation cost of this material is extremely low and there is no need to change the design.
In an induction motor, the rotating magnetic field of the stator generates an induced current in the rotor, and the electromagnetic force generated thereby causes the rotor to rotate. The system has simple configuration, low cost, and strong maintainability. On the contrary, the permanent magnet synchronous motor rotates by the magnetic attraction between the stator rotating magnetic field and the permanent magnet of the rotor. It is usually more expensive than the induction motor, but has higher controllability and efficiency.
The company tested on the induction motor of the railway vehicle drive system and confirmed that its efficiency has increased by 0.9%, which is close to that of a permanent magnet synchronous motor. Toshiba said this material can also be installed on permanent magnet synchronous motors to achieve higher efficiency. The material also has excellent heat resistance and is suitable for applications such as railway vehicles, automobiles and robots.
Motor slot wedge is a component that tightly fixes the coil in the slot, usually made of non-magnetic material. It is found that the use of magnetic materials can improve the magnetic permeability of the slot wedge, thereby increasing the energy conversion efficiency. However, the conventional magnetic materials used for slot wedges are composed of spherical magnetic metal particles, which do not control the magnetic flux sufficiently and easily cause unnecessary leakage. At the same time, the magnetic loss of the magnetic slot wedge material itself is also very high, and the heat resistance is poor, not suitable for railway vehicles and other applications with high heat resistance requirements.
Toshiba's new magnetic materials have unique properties that can excellently control magnetic flux and provide high heat resistance. This material is composed of sheet-shaped magnetic metal particles, and its magnetic properties vary depending on the direction, and the magnetic loss is extremely low.