1 f Full Wave mC Bridge Rectifier 8554

Categories: Power Electronics


Thyristorised Closed loop speed control of 3 phase Induction.

MOTOR :     This trainer is designed for speed control of 3 phase induction motor using V/F method. Voltage control is obtained by 3 phase SCR fully controlled converter and Frequency control is obtained 3 phase SCR inverter. Both voltage & frequency are simultaneously controlled.

This unit consists of:

i.      3 phase fully controlled converter.

ii.      3 phase Mc – Murray Inverter.

iii.      PI controller for closed loop.

iv.      Motor set – up.

*          Three phase fully controlled converter for Voltage


*     Six Isolated gate signals for Full Bridge Converter.

*     Firing Angle variable from 1800 to 0through Ramp and pedestal control.

*     Gated carrier source at 4 KHz.

*     Test points are provided on the front panel for detailed study of circuit signals by the student.

*     Necessary test points are terminated at sockets so that the student can monitor / measure/study the signals using CRO, DVM, etc.

*     One potentiometer to vary the firing angle. monitor all the test points of the control circuitry for correct functioning.

*     Six SCR’s each rated at 1200V @ 25 A, Each SCR is provided with RC snubber.

*     The SCR’s are mounted on suitable heat sinks and placed inside a nicely designed cabinet.

*     Facilities are provided for switching ON and OFF, the AC supply to the converter circuit with fuse and miniature circuit Breaker protection.

*     Provided with one Voltmeter to indicate DC Voltage variation.


*     Six isolated gate pulses are provided to fire the six number of SCR’s.

*     One Potentiometer provided to vary the frequency of the inverter from 10Hz – 50 Hz.

*     One Potentiometer provided to vary the frequency of the inverter.

*     All gate pulses are Isolated by pulse isolation transformer.

*     Six SCR’s rated 1200V / 25A provided.

*     Six Diodes rated 1200V / 6A provided.

*     6 Nos. of Commutating capacitors and 3 Nos. of center tapped inductors (Rating at 120mH, 4A) provided.

*     All 6 Nos. of SCR’s, Diodes, Capacitors & Inductors forms 3 phase inverter with 180o mode conduction.

*     DC Input of inverter fed from three phase SCR converter.

*          POWER SUPPLY :

*     + 15V regulated DC power supply for control circuitry.

*          CLOSED LOOP :

*     Analog PI Controller provided for closed loop operation.

*          MOTOR SETUP :

*     One 1hp three phase Induction motor with spring balance load setup.

*     One optical encoder is provided for the speed measurement.

*     The output of optical encoder is signal conditioned & calibrated to indicate the speed of the AC motor & give feedback signal for closed loop.