时间：2011-03-11 23:13来源：蓝天飞行翻译 作者：admin 点击：次
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As soon as the rotor is turning at the correct speed, the start winding is automatically disconnected, and the inertia of the heavy rotor keeps it spinning in the pulsing magnetic field produced by the run winding. Three-phase induction motors do not need separate start windings, because the three separate phase windings produce a rotating magnetic field. induction period (aircraft finishing system condition). The period of time after a catalyzed material, such as an epoxy or polyurethane, is mixed before it is ready to be sprayed onto the surface of the aircraft. The induction period allows the material to begin its curing action before it is applied. induction system (aircraft reciprocating engine system). The entire system in an aircraft reciprocating engine that carries air into the engine cylinders. The induction system consists of the air filter, carburetor heater or alternate air valve, the turbocharger, and all the piping used to carry this air into the cylinders. induction vibrator (reciprocating engine ignition system component). An electrical relay connected in such a way that it chops up direct current and produces pulsating DC. The pulsating DC is sent through the primary winding of the magneto coil where it induces a high voltage in the secondary winding. This high voltage causes a spark to jump across the gap in a spark plug. Induction vibrators are used with magnetos to produce a hot spark for starting the engine when the magneto is turning slowly. induction welding. A method of welding in which the metal is melted by heat generated by alternating current induced into the metal. inductive circuit. An alternating current circuit in which the inductive reactance is greater than the capacitive reactance. Changes in the current flowing in an inductive circuit lag behind changes in the voltage. inductive kick. A pulse of high voltage produced across a coil when current flowing through it is interrupted. When direct current flows through a coil, a magnetic field surrounds each turn of wire, and this magnetic field is sustained as long as the current flows. When the current is interrupted, the magnetic field instantly collapses, and the lines of magnetic flux cut across each turn of the coil. This collapsing field induces a short-duration pulse of voltage into the coil that is many times greater than the original voltage. This pulse of high voltage is called an inductive kick, or a transient voltage spike. inductive reactance. An opposition to the flow of alternating current or changing direct current, caused by inductance in the circuit. Inductive reactance, whose abbreviation is XL, is measured in ohms, and it decreases the amount of current flowing in a circuit. Resistance is also measured in ohms, and it too decreases the current, but resistance uses power and produces heat, while inductive reactance does not. Inductive reactance is caused by the generation of an induced voltage whose polarity is opposite to that of the voltage causing it. The induced voltage opposes some of the applied voltage, and because there is less voltage available to force current through the circuit, less current flows. Inductive reactance increases as both the frequency of the alternating current and the inductance of the circuit increase. The formula for inductive reactance is: |
