Three Phase Bidirectional Delta Connected Controller:
Description : Explain three phase half wave controller or three phase unidirectional controller.
Answer : Three phase half wave controller or unidirectional controller:
Description : Explain three phase full wave controller.
Answer : Three phase full wave controller: Three phase full wave controller is also called as the three-phase bidirectional controller. Let the load is star connected so at each phase there are antiparallel connected SCRs. ... conduct at the same time and the third phase will be open.
Description : A balanced Delta connected load supplied with 440 V 50 Hz three phase AC supply has R=10 Ohm and L=0.6 mH in is each arm. Calculate line and phase current, active power.
Description : Draw the Delta connected three phase system showing all the voltages and currents. Write the power equation.
Description : Explain the principle of ON-OFF control and phase control of AC voltage controller with suitable circuit and waveforms.
Answer : The integral cycle control (on-off control) and phase angle control are the two types of AC voltage controller. The principle of ON-OFF control: The on-off control is also called an integral cycle ... control. In phase control, the switch is on for some period of each cycle.
Description : Explain three phase bridge inverter.
Answer : Three phase bridge inverter: Three phase bridge inverter converts DC voltage input to three-phase variable frequency variable voltage output. DC voltage source can be a DC source or output of the rectifier. ... in proper sequence. The switch may be thyristor or IGBT etc.
Description : Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these
Answer : Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these
Description : When three resistors with unequal values are connected in parallel, _______ A) The current across the resistors is the same B) The voltage drop across the resistors is the same C) The voltage drops across the resistors is proportional to the resistance of each resistor D) None of these
Answer : When three resistors with unequal values are connected in parallel, The voltage drop across the resistors is the same
Description : three phase to single phase cycloconverter
Answer : three phase to single phase cycloconverter
Description : List different starting methods of three phase synchronous motor. Explain any one of them.
Answer : Different Starting Methods of Three Phase Synchronous Motor: As synchronous motor is not self starting, different methods of starting are as follows: 1) By using an Induction (Pony) motor 2) ... . The rotor gets pulled into synchronism and starts running at constant speed as a synchronous motor.
Description : Explain with neat circuit diagrams the procedures to perform no load and blocked rotor tests on three phase induction motor.
Description : Explain the need and steps to conduct the reduced voltage running up test on the three phase induction motor.
Description : Explain power relations in three phase circuit.
Description : In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be -
Answer : In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be 3
Description : Why is a capacitor used in a single phase motor and not in three phase motor ?
Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.
Description : Why is a three phase denoted by R, Y, B ?
Answer : phase 1 ,R =Red colour cable terminal, phase 2 Y=Yellow colour terminal cable,Phase 3 B=Blue colour cable terminal, N =Neutral. For identification.
Description : State any four advantages of three phase induction motor.
Answer : Advantages of three phase induction motor https://youtu.be/27OIOCKN05U
Description : Define balanced and unbalanced load in three phase circuit.
Answer : Balanced Load: When all the imedances of 3 phases are equal in magnitude and of same nature then load is said to be balanced. Unbalanced Load: When all the imedances of 3 phases are not equal in magnitude and of different nature then load is said to be unbalanced.
Description : State any four applications of three phase circuits.
Answer : The application of three phase circuits are 1. Three phase circuit is used for power transmission over long distances. 2. Three phase circuit can produce rotating magnetic field 3. Three phase ... three phase Motors and Transformers. 4. Three phase circuit is used for power converters circuits.
Description : Draw the waveform of three phase AC supply voltage.
Description : State advantages of three phase over single phase.
Answer : Advantages of 3-phase system over 1-phase system: - 1. More output: For the same size, output of poly-phase machines is always higher than single phase machines. 2. Smaller size: For ... are self- starting: The three phase ac motors are self starting, while single phase induction motor are not.
Description : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is
Answer : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 4 percent
Description : When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is (A) 86.6% (B) 50% (C) 57.7% (D) 73.2%
Answer : When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is 73.2%
Description : In a three-phase supply floating neutral is undesirable because it way give rise to?
Answer : In a three-phase supply floating neutral is undesirable because it way give rise to unequal line voltages across the load.
Description : Three phase synchronous motor will have how many sliprings?
Answer : Three phase synchronous motor will have two sliprings.
Description : How is a three phase cage induction motor self starting?
Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting
Description : What is mean by plugging in three phase induction motor?
Answer : Plugging in three-phase induction motor means interchanging of any two phases of a stator for quick stopping.
Description : What is a three phase connection?
Answer : RYB, 440 volt/phase
Description : how can we reverse the direction of rotation of three phase induction motor ?
Answer : The direction of rotation of three phase induction motor can be reversed by plugging i.e by changing any two out of three phases of the supply to the stator of the Induction motor terminal.
Description : What is line voltage and phase voltage? Draw balanced three phase star connected system. Show all the voltages and currents.
Description : Write short notes on 3 phase AC system.
Description : Temperature controller using SCR
Answer : Temperature controller using SCR The temperature control circuit is used to regulate the temperature. Figure shows the temperature control circuit using thermostat as temperature detector and SCR as ... half-cycle and heater gets connected to source to produce heat and raise the temperature.
Description : Draw and explain pneumatic proportional controller.
Answer : Explanation : Basic : Proportional control is one in which the process input is change in direct proportion to the error(t) controls the output so that the manipulated variable and the error has proportional relation. ... the MV and SP reference value called as error Given as : Error = SP - MV
Description : Explain Keypad controller.
Answer : Keypad Controller: It's a device which interfaces between the computer and keyboard. That is a input device and used for transfer the data to connected device.
Description : Explain the open delta (delta-delta) test on transformer.
Description : A four -quadrant operation requires two full converters connected in (1) Series (3) Back to back (2) Parallel (4) Series Cascade
Answer : A four-quadrant operation requires two full converters connected in Parallel
Description : Three identical resistors connected in star consume 5000 W. If the resistors are connected in delta across the same supply, the power consumed will be
Answer : Three identical resistors connected in star consume 5000 W. If the resistors are connected in delta across the same supply, the power consumed will be 15000 W
Description : With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals?
Answer : Power is the only thing which is additive in both connection whether it is parallel or series connection so total power consumed will addition of all individual power =20+20+20 = 60 watt
Description : What is the purpose of auxiliary controller in substation?
Answer : The systems of substation auxiliaries ensure operation of substations providing internal consumers of substations with operating direct and alternating currents. Any breakdown (loss) of auxiliary systems ... whole substation, as well as serious problems during its subsequent putting into operation.
Description : Define Integral controller. State their advantages
Answer : Advantages of integral control action: 1) Improves steady state response 2) Removes offset error in the process variable. 3) Eliminates steady state error
Description : When to select P-I controller? Give any two application of P-I controller.
Answer : Selection of P-I controller: The PI mode of controller is commonly selected for slow-to- moderate speed processes. Fast response of the system is not required. Large disturbances and ... an issue. As a adaptive controller for flow process. Real time pressure control process.
Description : A Unified Power Flow Controller (FACTS controller) is a voltage source converter based (A) Inter-phase power controller (B) Static Compensator (C) Combination of series and shunt compensators (D) Solid-state series compensator
Answer : A Unified Power Flow Controller (FACTS controller) is a voltage source converter based Combination of series and shunt compensators
Description : What is an electronic controller?
Description : The sequence components of current of a single-phase load connected to a 3-phase system are (A) equal positive and negative sequence components (B) equal positive, negative and zero sequence components (C) vector sum of sequence currents is zero (D) algebraic sum of sequence currents is zero
Answer : The sequence components of current of a single-phase load connected to a 3-phase system are equal positive, negative and zero sequence components
Description : Delta to Star Conversion Example
Answer : Delta to Star Conversion Example
Description : Wye (Star) to Delta Conversion
Answer : Wye (Star) to Delta Conversion
Description : Delta to Wye Conversion
Answer : Delta to Wye Conversion
Description : Star to delta conversion examples
Answer : Star to delta conversion example 1
Description : Wye and delta conversion formula
Answer : Wye and delta conversion formula
Description : Wye Delta Transformation
Answer : Wye Delta Transformation 1 : https://youtu.be/mPKeczDWZCo Wye Delta Transformation 2 : https://youtu.be/k80VbHI-wwg Wye Delta Transformation 3 : https://youtu.be/6cnwj15uw5M Wye Delta Transformation ... 8 : https://youtu.be/knRb5UW1404 Wye Delta Transformation 9 : https://youtu.be/JBwHKBJ08WM