Switched reluctance motor (SRM) has merits of rigid and simple structure, simple converter circuit with fault tolerance, high starting torque, premium speed regulation performance, high speed capability, high torque to inertia ratio. However, the SRM suffers from noticeable torque ripple due to discrete nature of the torque production, acoustic noises, high nonlinear characteristics due to the doubly saliency structure. The nonlinearity in the operation of the SRM complicates the analysis as well as the control of the motor [1-5]. Based on the modelling of SRM magnetic circuit, three models of SRM are found in literature: linear model, nonlinear model without mutual inductances, and nonlinear model with mutual inductances. Linear models in [6,7] are designed and simulated readily. On contrast nonlinear models are obtained after a large set of experimental tests to obtain the magnetic characteristics [8-15], or from a finite element method (FEM) analysis [16-18], which takes into consideration the saturation of rotor and stator materials. The nonlinear model is preferable when accurate precision is wanted. The converter used with SRM requires at least one switch per phase due to unidirectional phase current. This is a big advantage when compared to the converters for AC motor drives. Some configurations of converters used in SRM drives are presented in [19-22]. The half-bridge asymmetric converter is the most widely used for SRM drive applications, because of its high
The equivalent electrical circuit of a dc motor is shown in figure 5.2. It can be represented by a voltage source (Va) across the coil of the armature. The electrical equivalent of the armature coil can be described by an inductance (La) in series with a resistance (Ra) in series with an induced voltage (Vc) which
| Jonathan Archer and Zefrem Cochrane are employees of the Rugged Trucks Company, a light truck division of Gigantic Motors Corporation.
Brushless DC motors are a vital part of the technology we use today in many different aspects of life; a common being computers. This essay will study how a brushless DC motor works, it’s pros, cons and how it compares to a brushed DC motor. Throughout will be various physics concepts and terms in order to provide the most accurate and detailed explanation.
Electrical Motors Control II Project The class I am now taking is Electrical Motors Control II. Motor controls. A motor controller is a device or group of devices that serves to govern in some predetermined manner the performance of an electric motor. A motor controller might include a manual or automatic process for starting and stopping the motor, selecting forward or reverse rotation. This project was put together by me, Olen and Melvin. Constructing a motor control panel consists of many factors, such as; meeting the customer’s specifications, desired operations, state and local regulations. Every electric motor has to have some sort of way to control it. The motors will have various ways to be started, stopped, reversed, and even ways to control the speed of the motors. These features can be complex depending on the task that the motor will be performing. By being able to do these things with the motors in various ways, helps make the task at hand a much simpler and less time consuming process. Allowing workers to get their job completed more efficiently. In this project that we were instructed to build we started with 240 volts AC power. We ran from the main three phase power to three fuses, then to our starter and overloads then onto our first motor. We repeated the process of Motor 1 for the second motor as we ran to three different fuses than that of the first motor. When then ran from the fuses to a transformer to step the voltage down. From the transformer we
Starting Current of both motors were different, when analyzed using ETAP. Starting current of Induction motor was more than that of the synchronous motor. However Induction motor is used for Stable operation in running condition [1]
addition, there were 90% of orders from custom motor, about 50% of the total annual
Today's central air conditioners offer significantly more energy efficiency than those manufactured even 5 to 10 years ago. In fact, recent model's of AC consumes up to 40% less energy, while producing the same amount of cooling. When selecting a new unit for air conditioning installation, the factors you will want to consider are energy efficiency, proper sizing, and your budget. Variable speed motors are one of your options for saving energy. Whether you need a new installation or air conditioning repair in Arlington, TX, Minuteman Heating & AC can provide the quality HVAC services you need.
Ten years ago our electric motor business was in real trouble. Low labor rates allowed the Eastern Bloc countries to sell standard motors at prices we were unable to match. We had become the high-cost producer in the industry. Consequently, we decided to change our strategy and become a specialty motor producer. Once we adopted our new strategy, we discovered that while our existing cost system was adequate for costing standard motors, it was giving us inaccurate information when we used it to cost specialty motors.
The brushless DC motors are becoming more popular in low and medium power applications due to the characteristics they have such as better speed versus torque characteristics, high dynamic response, high efficiency, noiseless operation and higher torque to weight ratio. They also have a long life span. With rapid development in power electronics, semiconductor and manufacturing technology for high performance magnetic materials, the brushless DC motors have been used for energy savings applications such as air conditioners, refrigerators, air pumps, kitchen appliances and electric vehicles.
L. Hsiu et al. [34] at low output ripple and noise in voltage and current and for this design a model of coupled inductor and transformers on a common core is use that provide Zero-voltage– switched Dual–SEPIC converter with coupled inductor. H. F. Bilgin et al. [35] gave a design criteria, operating feature and characteristic of the buck type PWM rectifier employed in a unity PF dc motor drive. As per this paper single–stage UPF buck –type PWM uses For-low harmonic distortion in Ac supply current and nearly UPF over a wide operating shaft speed Range. And these output voltage and current in limit avoid any type of failure risk in current connection even for oldest motor design, aging in insulation, mechanical failure due to circulation
This motor (similarly to any other electrical motor) has a stator and a rotor; the stator's role is to carry a three phase winding (stator winding) which is supplied from a three phase supply. While the rotor's role is to carry a short circuit winding (rotor winding), the electromagnetic induction is the way through which the rotor winding gains the voltage and the power from the stator winding.
Second-throat ejector-diffuser systems are used in high-altitude testing of large-area-ratio rocket motors. The performance of these systems is dependent on the stagnation pressure, the diffuser back pressure, convergence angle, second throat diameter and length, and the diffuser exit diameter. [1] These variables were all tested to see how they impacted the performance of these systems in high-altitude testing (HAT) facilities. The most important performance characteristic of these systems measured in testing was maintaining the required vacuum for testing the motor. The creation of oblique shock waves in the diffuser seals the vacuum chamber to create a successful test environment for the motor. This study stood out from others based on
Abstract: The area of the multiphase motor has experienced a significant growth in last decade numerous interesting development have been reported in the literature in this chain this paper is an attempt to mathematically model both three phase and six-phase induction motor for comparison of their characteristics. Using this mathematical modeling a Simulink model is created whose results shows that the six-phase induction motor can sustain more than four times the torque that can be sustained by three phase induction motor of same design parameters. The six-phase motor is better not just in torque handling capacity but it also has inherent advantages of the multiphase induction motor.
Power electronic converters, especially DC/AC inverters have been extending their range of use in industrial application because they provide better system efficiency, reduced energy consumption and improved quality of power. The output voltage of inverter could be fixed or variable at a fixed or variable frequency and output waveforms are therefore made up of discrete values, producing fast transition
Hybrid cars have been around for a long time. Much longer than any of us have even thought. The first battery powered machines came way earlier, but for the hybrid cars we think of today, these models started coming out around 1888. “A vehicle is a hybrid if it utilizes more than one form of onboard energy to achieve propulsion. In practice, that means a hybrid will have a traditional internal-combustion engine and a fuel tank, as well as one or more electric motors and a battery pack.” (Edmunds) The gas is used to fuel the car but the main source of the power comes from the electric motor. There have also been companies, like Porsche, who have created hybrids that used an internal combustion engine that would turn a generator that powered an electric motor. A car with just the electric motor is not a hybrid, it’s just an electric car. Many companies have seen the growing field of hybrids cars and plan to expand their showcases with these new cars. Some of these companies include Honda, Volvo, and Cadillac.