How do you perform a short circuit and open-circuit test on a synchronous generator?
The basic test procedure is as follows:
- Set the field current to zero.
- Short circuit the armature terminals.
- Drive the generator at synchronous speed with external mechanical system.
- Slowly increase the field winding current until the short circuit armature current reaches the rated design value.
What is OCC and SCC test?
Open Circuit Test and Short Circuit Test are performed on a Synchronous Machine to find out the Synchronous impedance For Large Machine to Determine the voltage regulation.
What is the purpose of short circuit test in generator?
The purpose of a short-circuit test is to determine the series branch parameters of the equivalent circuit of a transformer.
How a synchronous generator is represented in short circuit analysis?
For a steady-state operation, generators are represented with a constant e.m.f behind a synchronous reactance, Xs under transient conditions. The machine reactance changes due to the effect of the armature (transformer) reaction and eddy currents in the damping circuits.
What is open-circuit test in alternator?
Leading power factors assist the rotor, and lagging power factors oppose it. The open-circuit test or the no-load test, is performed by driving the generator at its rated speed while the armature winding is left open.
What do you mean by short circuit?
short circuit. noun. a faulty or accidental connection between two points of different potential in an electric circuit, bypassing the load and establishing a path of low resistance through which an excessive current can flow. It can cause damage to the components if the circuit is not protected by a fuse.
What is OCC and SCC in synchronous generator?
Open circuit characteristic (OCC) and Short Circuit Characteristics (SCC) of a Synchronous generator. With the armature terminals open, Ia=0, so Eg = Vt It is thus possible to construct a plot of Eg or Vt vs If graph.
What is the characteristics of short circuit test?
A short circuit is a direct connection between two terminals. The short circuit maintains zero voltage drop and can allow any current, so its I-V characteristic is a vertical line at V=0.
What is open circuit and short circuit test?
The open circuit and short circuit test are performed for determining the parameter of the transformer like their efficiency, voltage regulation, circuit constant etc. These tests are performed without the actual loading and because of this reason the very less power is required for the test.
What is open circuit test and short circuit test?
Open circuit test and short circuit test are conducted to determine the core loss, copper loss, and equivalent circuit parameters of a transformer.
How can you determine the open circuit characteristics of synchronous generator?
For getting the Open Circuit Characteristics of Synchronous Machine, the alternator is first driven at its rated speed and the open terminal voltage i.e. voltage across the armature terminal is noted by varying the field current.
What is short circuit ratio of generator?
Short circuit ratio or SCR is a measure of the stability of an electromechanical generator. It is the ratio of field current required to produce rated armature voltage at open circuit to the field current required to produce the rated armature current at short circuit.