Due to their simple structure, high efficiency, fast dynamic response, Permanent Magnet Brushless DC (PMBLDC) machines are extensively used in automation, consumer electronics, electric vehicles and medical and industrial applications. Availability of these high energy density permanent magnet materials enhances the performance of PMBLDC motor drive and also reduces the size and losses in these...

Electrically excited synchronous machines have become one of the potential alternatives to permanent magnet in electric vehicles avoid rare-earth materials. Utilizing high-frequency brushless exciters for rotor excitation is a promising choice reduce friction losses and maintenance effort cost. However, with usage exciters, field current temperature cannot be measured directly. In this article,...

The Permanent Magnet Brushless DC (BLDC) motor offers higher efficiency, low maintenance, reduced weight and compact construction. For many industrial applications, the BLDC motor is increasingly being used. This paper presents a new sensorless drive scheme for BLDC motor based on the back EMF difference. The commutation point of the drive is determined by detecting the Zero Crossing Point (ZCP...

This paper discusses the suitability of four-phase, five-phase, and six-phase modular machines, for use in applications where servo characteristics and fault tolerance are key requirements. It is shown that an optimum slot number and pole number combination exists, for which excellent servo characteristics could be achieved, under healthy operating conditions, with minimum effects on the power ...

To promote energy saving, we developed a high efficiency brushless DC motor with a new manufacturing method of a stator for compressors. This motor consists of a concentrated winding stator and an interior permanent magnet rotor. The stator has the core structure that we call “a joint-lapped core”. The joint-lapped core is able to open and bend in reverse. While winding the coil, the joint-lapp...

This paper presents a sensorless drive technique for permanent-magnet brushless DC motors applied to electric propulsors of small ships or underwater vehicles. Propulsors enveloping electric motors (e.g., POD or subsea thrusters) have been increasingly applied due to their advantages of excellent maneuverability, high efficiency and low maintenance costs. To secure reliable operation under wate...

The objective of this project is to build a simple current controlled modulation technique for brushless dc motors. In electric traction and most other applications, a wide range of speed and torque control of the electric motor is required. The dc machine fulfills these requirements, but the dc machine requires constant maintenance. But the brushless permanent magnet motors do not have brushes...