Explain the three phase 120 degree mode VSI.

1 Answer

Answer :

Three phase 120 degree mode VSI:

In the 120-degree mode voltage source inverter, each thyristor conducts for 120 degree of a cycle. 120-degree mode VSI required six steps, each step of 60 degree duration for completing one cycle of output AC voltage. During each step, only two thyristors will conduct, one thyristor will conduct from the upper group and one thyristor will conduct from lower group.

image image

image

Related questions

Description : What is Voltage Source Inverter (VSI) ?

Last Answer : Voltage Source Inverter (VSI)  Inverter is device which converts Direct Current (DC) to Alternating Current (AC). There are two types of inverters one is Voltage source inverter ... VSI consist of two load terminals and three phase VSI consist of three load terminals.

Description : Give the circuit analysis of current source inverter with resistive load. What are the main difference between voltage source inverter and current source inverter?

Last Answer : Current source inverter (CSI): In current source inverter, the output current is independent of load. The input current of current source inverter is constant. Current source converter converts DC input current to ... are connected in parallel. In CSI diodes are connected in series.

Description : A 3-phase voltage source inverter is operated in 180o conduction mode. Which one of the following statements is true ?  (A) Both pole-voltage and line-voltage will have 3rd harmonic components ... from 3rd harmonic (D) Both pole-voltage and line-voltage will be free from 3rd harmonic components

Last Answer : A 3-phase voltage source inverter is operated in 180o conduction mode. Which one of the following statements is true ?  (A) Both pole-voltage and line-voltage will have 3rd harmonic components ... from 3rd harmonic (D) Both pole-voltage and line-voltage will be free from 3rd harmonic components

Description : If cabin pressure is decreasing, the cabin VSI will indicate

Last Answer : B. Climb

Description : If cabin pressure is decreasing, the cabin VSI will indicate: a. Zero b. Climb c. Descent d. Reducing pressure

Last Answer : b. Climb

Description : If cabin pressure is decreasing, the cabin VSI will indicate: a. Zero b. Climb c. Descent d. Reducing pressure

Last Answer : b. Climb

Description : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is  (1) 141 (2) 92.3 (3) 9.23 (4) 1.41

Last Answer : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is 9.23

Description : Explain three phase half wave controller or three phase unidirectional controller.

Last Answer : Three phase half wave controller or unidirectional controller:

Description : Explain Three Phase Bidirectional Delta Connected Controller.

Last Answer : Three Phase Bidirectional Delta Connected Controller:

Description : Explain three phase bridge inverter.

Last 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 : Explain three phase full wave controller.

Last 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 differential amplifier has a differential gain of 20,000, CMRR : 80 dB. The common mode gain is given by

Last Answer : A differential amplifier has a differential gain of 20,000, CMRR : 80 dB. The common mode gain is given by 2

Description : The threshold voltage of an n- channel enhancement mode MOSFET is 0.5V when the device is biased at a gate voltage of 3V. Pinch off would be occurs at a drain voltage of (A) 1.5V (B) 2.5V (C) 3.5V (D) 4.5V

Last Answer : The threshold voltage of an n- channel enhancement mode MOSFET is 0.5V when the device is biased at a gate voltage of 3V. Pinch off would be occurs at a drain voltage of 2.5V

Description : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that

Last Answer : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that the transformers should belong to the same vector group

Description : three phase to single phase cycloconverter

Last Answer : three phase to single phase cycloconverter

Description : Explain the principle of ON-OFF control and phase control of AC voltage controller with suitable circuit and waveforms.

Last 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 : Draw single phase full wave mid-point converter for inductive load. Draw input and output waveforms for it. 

Last Answer : Circuit Diagram: Waveforms:

Description : State classification of Phase controlled rectifiers.

Last Answer : Classification of phase controlled rectifiers:

Description : Single-phase mid-point controlled rectifier with RL load

Last Answer : Single-phase mid-point controlled rectifier with RL load : The circuit configuration of single-phase midpoint controlled rectifier is shown in the figure. During positive half-cycle of ... some part of next positive half-cycle of voltage with reversed polarity can appear across load.

Description : Single-phase Midpoint controlled rectifier with Resistive load

Last Answer : Single-phase Midpoint controlled rectifier with Resistive load:  1) During positive half cycle of AC supply, a is positive with respect to b , this makes T1 forward biased and T2 is reverse ... voltage reverses the polarity and T2 is turned off. The operation is as shown in waveforms.

Description : Give the operation of single phase full wave bridge controlled converter with RL load with a neat diagram. Also draw its waveform.

Last Answer : Single phase fully control bridge converter with RL load: 1. During positive half cycle of input voltage, T1 and T2 are forward biased and during negative half cycle, T3 and T4 are forward biased. Therefore, T1-T2 ... cycle till the firing of next pair of SCRs as shown in the waveform.

Description : A single phase fully controlled bridge converter supplies a load drawing constant and ripple free load current, if the triggering angle is 30o, the input power factor will be  (A) 0.65 (B) 0.78 (C) 0.85 (D) 0.866

Last Answer : A single phase fully controlled bridge converter supplies a load drawing constant and ripple free load current, if the triggering angle is 30o, the input power factor will be 0.78

Description : In a single-phase full converter, the number of SCRs conducting during overlap is   (a) 1 (b) 2 (c) 3 (d) 4 

Last Answer : 4

Description : In a 3-phase half-wave rectifier, if per phase input is 200 V, then the average output voltage is   (a) 233.91 V (b) 116.95V (c) 202.56 V (d) 101.28V 

Last Answer : a

Description : Oscillator independent of phase shift is  (1) Relaxation (2) Wein bridge (3) Clapp (4) All of these

Last Answer : Oscillator independent of phase shift is Relaxation 

Description : A single-phase voltage source square -wave inverter feeds pure inductive load. The waveform of the load current will be

Last Answer : A single-phase voltage source square -wave inverter feeds pure inductive load. The waveform of the load current will be triangular

Description : A 3 -phase, fully controlled, converter is feeding power into a DC load at a constant current of 150 A, the rms value of the current flowing through each thyristor of the converter is

Last Answer : Please show the solution for this question

Description : When the firing angle a of a single-phase, fully controlled rectifier feeding constant direct current into a load is 30°, the displacement power factor of the rectifier is

Last Answer : When the firing angle a of a single-phase, fully controlled rectifier feeding constant direct current into a load is 30°, the displacement power factor of the rectifier is √3/2

Description : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is (A) 4.5 V (B) 6.75 V (C) 9 V (D) 13.5 V

Last Answer : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is 9 V

Description : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is (A) sinusoidal current (B) constant dc current (C) continuous rectangular pulses (D) alternating rectangular pulses

Last Answer : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is alternating rectangular pulses

Description : What is a phase control thyristor?

Description : Describe the gate circuit for a single phase full converter.

Description : single phase full converter

Last Answer : single phase full converter

Description : The electrical schematic shown in the illustration indicates the lighting feeder circuit is _____________. EL-0014 A. three phase, 450 volt, and 60 cycle B. three phase, 120 volt, and 60 cycle C. single phase, 120 volt, and 60 cycle D. not specified

Last Answer : Answer: A

Description : What will be the frequency of a three-phase, six pole, AC generator operating at 1800 revolutions per minute? A. 60 hertz B. 90 hertz C. 120 hertz D. 180 hertz

Last Answer : Answer: B

Description : A three-phase synchronous motor has a terminal voltage of 460 V and a terminal current of 120 A at a power factor of 0.95 lagging, synchronous reactance of 1.68 ohm and the field current is 47 A. The field to armature mutual ... _____________.      (a). 20mH   (b). 16mH   (c). 24mH   (d). 22mH

Last Answer : 22

Description : Is it possible for a city to be located at 120 degree S 30 degree W explain?

Last Answer : Not possible... because - you can only have a location between 0and 90 degrees from the equator.

Description : Is it possible for a city to be located at 120 degree south and 30 degree west?

Last Answer : Logically not, because no place on earth can have a latitude of 120° South. The south pole is at latitude 90° South, and you can't go any farther south than that.

Description : Is it possible for a city to be located at 120 degree south and 30 degree west?

Last Answer : Logically not, because no place on earth can have a latitude of 120° South. The south pole is at latitude 90° South, and you can't go any farther south than that.