A Daikin IPM motor is superior because it uses a double rotational force produced by two types of torque: neodymium (magnet torque) and Daikin’s original reluctance torque. The combination of these two forces increases power while using less electricity to deliver energy savings.
Powerful neodymium magnets are what gives Daikin IPM motors their energy-saving effect.
A rare-earth permanent magnet deeply positioned in the rotor generates magnet torque (attraction/repulsion between coil and permanent magnet) and reluctance torque (coil attracts iron). This electromagnetic structure attains high torque for the highest possible efficiency.
The lengths of the magnetic field lines at the south and north poles are equivalent, which means there’s no rotational force or reluctance force generated.
The magnetic field lines at the south pole side are longer than the north side. Similar to how a stretched rubber band contracts, the magnetic field lines at the south pole will try to shorten. As a result, a rotational force will occur due to the reluctance torque moving in a counterclockwise direction (see the arrow in the illustration).
The efficiency of a Daikin IPM is much higher than an induction motor, especially at low motor rotation speed.
Daikin IPM motors produce high torque at a low speed. Generally, an inverter type may have limited torque when set at a low-speed range, but Daikin IPM motors can work around this technicality.
Daikin's unique energy saving technology with a IPM motor will be presented. The IPM motor features high efficiency, high rotation speed and high response, which have the characteristics required for hydraulic systems. The IPM motor selects power phases to maximize the composited torque made from the magnet torque and reluctance torque, which produces the highest efficiency.