Speed control of dc series motor - motor control , Electrical Engineering

Speed Control of DC Series Motor

A half  wave  circuit  for the  speed  control of DC  series motor is  shown in figure and corresponding wave from  is shown  in figure  consists  diac  and diode  to give the  triggering pulses to the SCR. Here SCR  is used to  control the armature voltage  of the DC motor.  By varying R2 firing angle α can be  controlled  of SCR. During the positive  half  cycle of input  ac voltage capacitor C will through R1 and R2.

SCR will get  turned  on when the  capacitor voltage Vc is equal  to the addition  of back emf Eb  of motor  and break over voltage VBO of the diac. By  varying  the resistance R2 the charging  time of  capacitor (r= R2C)  hence the speed of motor can be controlled. Basically it is  the armature voltage control method. In case  when SCR  is not conducting the  armature voltage will be there due to  the residual flux which  is approximate proportional  to the speed .

Due to  the fluctuation  in load will results the  change  in speed of motor and according  back emf of the motor will change. Since  the break over voltage of  diac is constant and back emf is varying  means the difference of Vc and ( VBO + EB) may increase or decrease as EB is increased or decreased respectively. The  firing  of SCR  depends on this difference. As  a results  the average dc voltage  across  the armature will change  and speed  of motor  can control  accordingly.

 

Posted Date: 4/3/2013 2:15:27 AM | Location : United States







Related Discussions:- Speed control of dc series motor - motor control , Assignment Help, Ask Question on Speed control of dc series motor - motor control , Get Answer, Expert's Help, Speed control of dc series motor - motor control Discussions

Write discussion on Speed control of dc series motor - motor control
Your posts are moderated
Related Questions
A switch-mode power supply is to be designed with the following specifications: input voltage V s = 48 V ± 10%, output voltage V o = 5 V, switching frequency f s = 100 kHz, outp

Analysis in equilibrium : Solution of Poisson's Equation with suitable boundary conditions - Non-equilibrium analysis: The electron and hole densities are no longe

Long-Term Plans for Technical Loss Reduction Long-term measures for technical loss reduction include all measures that require to be taken for the improvement of quality and r

Q. Explain from the drain characteristics that a JFET has  infinite resistance? When V GS = 0v when a positive voltage Vds has been applied across the channel and the gate

Speed Control of DC Shunt Motor V dc   the output of rectifying circuit which is  applied to the motor field  as shown  in figure  for armature voltage V dc   is controlled by

1.....If viewing this through the Assignment tool, click the title above to go to the Submissions area. Introduction The purpose of this experiment is to examine the opera

Q. Evaluate complex power in power system? The complex power ¯S in a single-phase systemis the complex sum of the real (P) and reactive (Q) power, expressed as follows:

The relationship between cell and batteries  Generally, a cell delivers a certain voltage that is a function of what chemical reactions are taking place to generate the voltage

Voltage Quality Standards - KPI The term voltage quality (or power quality) is an umbrella concept for a variety of disturbances within a power system. The quality of delivere

Revision  of Basics Although  it is  assumed in this book  that the  reader has  enough  knowledge of  various number systems ( binary, octal and hexadecimal and their relation