Load current is always negative in

This question was previously asked in
URSC ISRO Technical Assistant Electronics 20 August 2017 Official Paper
View all ISRO Technical Assistant Papers >
  1. Type E Chopper
  2. Type C Chopper
  3. Type B Chopper
  4. Type A Chopper

Answer (Detailed Solution Below)

Option 3 : Type B Chopper
Free
ISRO Technical Assistant Mechanical Full Mock Test
2.7 K Users
80 Questions 80 Marks 90 Mins

Detailed Solution

Download Solution PDF

A chopper is a static device that is used to obtain a variable dc voltage from a constant dc voltage source. Also known as a dc-to-dc converter.

Types of Choppers:

  • Type A Chopper or First-Quadrant Chopper
  • Type B Chopper or Second-Quadrant Chopper
  • Type C Chopper or Two-quadrant type-A Chopper
  • Type D Chopper or Two-quadrant type-B Chopper
  • Type E Chopper or fourth-quadrant Chopper

 

The circuit diagram of Type B Chopper is as shown:

F1 S.B Madhu 16.03.20 D11

  • When the chopper is ON, 'E' voltage drives a current through L in a direction opposite to that shown in the figure.
  • During the ON period of the chopper, the inductance L stores energy.
  • When Chopper is OFF, diode D conducts, and part of the energy stored in inductor L is returned to the supply.
  • Therefore the average output voltage is positive and the average output current is negative as shown:

 

        F1 S.B Madhu 16.03.20 D1

            F1 S.B Madhu 16.03.20 D12

  • In this chopper, power flows from load to source.
  • Class B chopper is used for regenerative braking of dc motor.
  • Class B chopper is a step-up chopper.
Latest ISRO Technical Assistant Updates

Last updated on May 30, 2025

-> The ISRO Technical Assistant recruitment 2025 notification has been released at the official website. 

-> Candidates can apply for ISRO recruitment 2025 for Technical Assistant from June 4 to 18.

-> A total of 83 vacancies have been announced for the post of Technical Assistant.

-> The Selection process consists of a written test and a Skill test.

-> Candidates can also practice through ISRO Technical Assistant Electrical Test Series, ISRO Technical Assistant Electronics Test Series, and ISRO Technical Assistant Mechanical Test Series to improve their preparation and increase the chance of selection. 

Get Free Access Now
Hot Links: teen patti master game teen patti master official teen patti gold download apk