External sources, synchronization

In physical terms the unidirectional synchronization means that the drive oscillator plays the role of an external source. The situation is different if one considers the problem of a mutual synchronization of two oscillators, which we may assume to be identical in all respect except for the initial conditions <7 <720 and pio / p2Q. Let us consider the following model of mutual synchronization... 

Since the synchronous motor has an external source of excitation power it can maintain flux for a longer time during a fault. The rotor pole face construction and the field circuit help to maintain the air-gap flux and generated emf. The decay of flux during the fault is determined for the most part by the transient impedance of the synchronous motor. 

Regenerative braking If the motor be run beyond synchronous speed by some external means it will work as a generator and feed back useful energy to the supply system. It will draw only the necessary excitation current, / , for the generator action from the source of supply. In such a condition, the motor... 

The driver is a prime mover capable of developing the required torque at a constant speed or over a range of speeds. The driver s energy source can be either electrical or mechanical. Electrical energy is used by motors, either of the induction or synchronous type, while the mechanical covers a multitude of sources. It may be a fuel, as in internal or external combustion engines, or it may be a gas, such as steam or process gas used in a turbine or expander. 

Of all the peripheral connection methods, none is as popular as serial. It s a simple, effective way to connect a peripheral to a PC. It is also cheap to manufacture, which is probably the main reason it s so popular. Serial connections transfer data one bit at a time, one right after another. The maximum speed of a serial connection is 128Kbps, so it isn t good for large amounts of data transfer, but it works great for synchronizing two data sources. The most popular application of a serial connection is connecting an external modem to a PC. 

Synchronous Generator - An electrical generator that runs at a constant speed and draws its excitation from a power source external or independent of the ioad or transmission network it is supplying. 

Synchronous Inverter - An electrical inverter that inverts direct current electricity to alternating current electricity, and that uses another alternating current source, such as an electric power transmission and distribution network (grid), for voltage and frequency reference to provide power in phase and at the same frequency as the external power source. 

Free-rimningoscillaton An oscillator that is not synchronized with an external timing source. 

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