Nowadays the control of stator voltage at a constant frequency is one of the traditional and low expense methods in order to control the speed of induction motors near its nominal speed. The torque of induction motor is a nonlinear function of the firing angle, phase angle and speed. In this paper the speed control of induction motor regarding various load torque and under different conditions ...

Successful endodontic treatment mainly relies on preserving the original anatomy of the root canal while avoiding instrument fractures and iatrogenic preparation errors, such as loss of working length, zipping, or ledging [1,2]. In most cases, rotary instrumentation has proved a valuable advancement for meeting these parameters. Unlike stainless steel files, nickel-titanium instruments have suf...

After much research and developments in the fields of magnetic materials their application to electric motor drives has increased to a significant extent. AC motors with permanent magnet rotors are available as brushless DC motors (BLDCM) for both domestic and industrial applications. With the advancements in power electronics, the control of Brushless DC machine has become more flexible for va...

The paper discusses the design of current waveforms for switched-reluctance motors, which give rise to a constant (ripple-free) torque. The waveforms are optimised by computer search techniques, to give the lowest RMS current per phase consistent with producing smooth torque. Furthermore. the waveforms are constrained to be within the converter’s VA rating. Current waveforms and the associated ...

To successfully follow a velocity profile, a motor and drive combination must generate enough torque to: accelerate the load inertia at the desired rates, and drive the load torque at the desired speeds. While the size of a bipolar stepper motor generally dictates the low speed torque, the ability of the drive electronics to force current through the windings of the motor dictates the high spee...

abstract: a continuously variable transmission (cvt) is a transmission which may change step less by way of an infinite variety of effective gear ratios between maximum and minimum values. this contrasts with different mechanical transmissions that solely permit just a few different distinct gear ratios to be selected. continuously variable transmissions (cvts) are mechanical devices that allow...

performing fast and accurate methods for modeling the electrical machines has been the subject of several studies and many authors proposed different procedures to attain this aim. beside the accuracy, the speed of the method is of great concern. on the other hand, the capability of the method to be changed according to the need is another important issue. finite element method provides relativ...

We consider theoretically the impact of Rashba spin-orbit coupling on spin torque oscillators (STOs) in synthetic ferromagnets and antiferromagnets that have either a bulk multilayer or a thin film structure. The synthetic magnets consist of a fixed polarizing layer and two free magnetic layers that interact through the Ruderman-Kittel-Kasuya-Yosida interaction. We determine analytically which ...