This causes the mass to deflect; the deflection is sensed by a suitable means and is converted into an equivalent electrical signal. B. Types of Accelerometer Sensors There are different types of accelerometers. Mechanical ones have something like a mass attached to a spring suspended inside an outer casing. When it is subjected to linear acceleration, the casing moves off immediately leaving behind the mass and spring stretches with a force that corresponds to the acceleration.
= Linear induction motors are electric induction motors that produce motion in a straight line rather than rotational motion. In a traditional electric motor, the rotor (rotating part) spins inside the stator (static part); in a linear induction motor, the stator is unwrapped and laid out flat and the "rotor" moves past it in a straight line. Linear induction motors often use superconducting magnets, which are cooled to low temperatures to reduce power consumption. In a traditional DC electric motor, a central core of tightly wrapped magnetic material (known as the rotor) spins at high speed between the fixed poles of a magnet (known as the stator) when an electric current is applied. In an AC induction motor, electromagnets is place around
The first is to use an optocoupler on the secondary circuitry to send a signal to the controller. The second is to wind a separate winding on the coil and rely on the cross regulation of the design. The first technique involving an optocoupler has been used to obtain tight voltage and current regulation,
ELECTROMAGNETIC CLUTCH An electromagnetic clutch is a clutch which operate electrically but transmit torque mechanically and is engaged and disengaged by an electromagnetic actuator. The electromagnetic clutch is most suitable for remote operation since no linkages are required to control its engagement. It has fast and smooth operation. But because of its energy dissipation as heat in the electromagnetic actuator every time the clutch is engaged, there is a risk of overheating. Consequently the maximum operating temperature of the clutch is limited by the temperature rating of the insulation of the electromagnet.
Therefore magnetic flowmeter is often used for wastewater applications or any dirty liquid which is conductive or water based. Non MAGNETIC FLOWMETER FLOW PRINCIPLES Magnetic flowmeters (mag flowmeter) operates by the principle of Faraday’s Law of Induction to determine the flow of the pipe. Faraday’s law states that the voltage induced across any conductor as it moves at right angle through a magnetic field is proportional to the velocity of the conductor. In magnetic flowmeter application, two field coils generate magnetic field across the pipe. Then, conductive fluid which acts similar like a conductor passes through the magnetic field produced by the two coils, therefore electrical voltage is induced.
Basic working principle of DC motor is based on the fact that whenever a current carrying conductor is placed inside a magnetic field, mechanical force is experienced by that conductor whose direction isgiven by Fleming' s Left-hand Rule and whose magnitude is given by F=BIL Newton. Hence for constructing a dc motor it is essential to establish a magnetic field. The magnetic field is established by means of magnet. The magnet can be of any type 1) electromagnet or 2) permanent magnet. When permanent magnet is used to create magnetic field in a DC motor, the motor is referred as Permanent magnet DC motor or PMDC motor.
There is a wide range of DC applications ranging from small to big applications in the industry. It is of vital importance for engineers to know motors so that they can choose the right one for their requirement. 1.1 PRINCIPLES OF OPERATION OF THE DC MOTOR In any electric motor, the basic theory by which all DC motors operate is electromagnetism. There are two states which are compulsory to produce a force
Thus, a 3-phase generator, also known as alternating current (AC) generator, is formed. Figure 2: Coils connected in perpendicular The blade of the rotating wheel has a curve-shape, so that the water can push the wheel to spin. Two concrete poles are placed on the side of the wheel with a gap, where a plastic tube goes through the octagon shaped armature and connect the two poles. The plastic tube acts as a connector for the poles as well as to place the copper wire safely away from being contact with water. The design will be kept sealed to prevent water from entering the device.
The solar panel voltage is given as input to the Buck-Boost converter circuit. The output of the Buck-Boost converter is used to drive DC fan, LED lamp etc. The current sensor and voltage sensor is used and their output is given to a comparator. The comparator output is given to ADC of the TMS320F2808 processor to generate PWM pulse which in turn drives the MOSFET of Buck-Boost converter. A closed loop system is used to get a constant output from the converter as 12
, are stator and rotor leakage inductances, is the amplitude of the mutual inductance stator-rotor. and are the pole pairs number and the electrical rotor position. An open circuit in one of the phases (assume phase c) means that will necessarily be zero, the phase affected will be removed to the electric circuit (FIG 1.b) which reduce the rank of matrix and i.e. Equivalent two phase model To express an equivalent two-phase model of the machine with one open phase, the above analytical representation can be transferred to an orthogonal axis reference frame (FIG 1.b). As long as the rotor hold a balanced structure, the well-known transformations for the balanced systems is always suitable [Lip].