What is Goerges phenomina to start SYCHNOUSMOTOR?
Answer / siva
The Goerges phenomenon is the operation of a 3-phase wound-
rotor induction motor at half of synchronous speedand it is
obtained by unbalancing the rotor circuit. If the motor is
started with one rotor phase opened or with rotor
impedances greatly unbalanced, it will accelerate to half
speed and operate stably as a motor or generator.The motor
may be operated stably at half or full speed. The torque at
half speed is greater than at full speed, and may be almost
as great as the rated torque for a balanced rotor. It may
be desirable to operate an induction motor at half speed
intermittently or as a temporary measure. Disadvantages of
half speed operation are the low power factor, low pull-out
torque, the subfrequency line currents, and motor
vibrations.
Is This Answer Correct ? | 2 Yes | 0 No |
Am i eligible to get electrical supervisor licence? As i did diploma as well as degree in Electrical Engg. in June 2011. Now i am working in 15 MW Power plant from 2 mnths. i belongs to Maharashtra.
1 hp single phase motor is more likely to get hot thsn inone hp 3 phase motor its true or false? If true why?
As all us know that the capacitor panel is connected to improve the power factor when it is PF is low. whether we can connect the capacitor panel on D.G. side(? If it is yes means why?
Why is starter necessary for a three-phase induction motor?
37 Answers BMM, Essar, Hero MotoCorp, ITI, Maruti Suzuki, Supertech, Watt,
sir i want previous entrance exam papers for written test
what is synchronizing panel & its working.
what will happen if multimeter(selector switch at DC voltage) and terminal at current is connected to DC supply?
when is safety goggles use mandatory?
Size of the 60Hz and 400Hz transformers is a) same b) 60Hz Tr s larger than 400Hz Tr c) 400Hz Tr s larger than 60Hz Tr d) None of the above
1. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.
What is mean by making & breaking capacity of circuit breakers?
what is d meaning of inrush current of a trafo ? how u can calculate this ?