The power electronics lab

Examine and understand power electronics

  • Line-commutated converters
  • Self-commutated converters
  • Frequency converters
  • Power factor correction (PFC)
  • Brushless direct-current
  • (BLDC) motors

UniTrain-I system

  • Comprehensive portable laboratory
  • Multimedia courses
  • High-tech measurement and control interface
  • Theory and practice both at once

UniTrain-I Interface with USB interface

  • Oscilloscope with 2 analogue differential inputs
  • Sampling rate 32 Msamples/s
  • 9 measuring ranges 100 mV - 50 V
  • 22 time ranges 1 �s - 10 s
  • 16 digital inputs/outputs
  • Function generator for frequencies up to 1 MHz
  • 8 relays for fault simulation

UniTrain-I Experimenter

  • Accommodates experiment cards
  • Experiment voltage supply � 15 V, 400 mA
  • Experiment voltage supply 5 V, 1 A
  • Variable DC or three-phase source 0 ... 20 V, 1 A
  • IrDa interface for multimeter
  • Additional serial interface for cards

 LabSoft training and experiment software

  • Huge selection of courses
  • Comprehensive theory
  • Animations
  • Interactive experiments with instructions
  • Free navigation
  • Documentation of experiment results
  • Tests

Integrated measuring equipment and power supplies

  • Multimeters, ammeters, voltmeters
  • Dual-channel storage oscilloscope
  • Function generator and waveform generator
  • Three-way power supply for AC and DC
  • Three-phase power supply
  • ... and many other instruments


Line-commutated converters

  • Uncontrolled rectifiers
  • Controlled rectifiers
  • AC controllers
  • Three-phase controllers

Having become an integral part of our daily lives,power electronics is what makes possible modern dimmers for halogen lights, variable-speed drills and adjustable electric heating, to quote a few examples. For this  purpose power semiconductors  like diodes, thyristors and power transistors are used.
The course on line-commutated converters deals with uncontrolled and controlled rectifiers as well as AC controllers. 16 different single-phase and three-phase circuits can be assembled and examined. Resistive, inductive and capacitive loads are available for all experiments. Appropriate virtual instruments to accompany the microcontroller experiment card make for easy circuit configuration as well as registration and display of all relevant
measurement variables.
Order number: SO4204-7N, consisting of

  • 1 x CD with course Line-commutated converters
  • 1 x Experiment card  Line-commutated converter
  • 1 x Experiment card Load line-commutated converter

Self-commutated converters

  • PWM
  • 1/4-quadrant controllers
  • Single phase inverters
  • Three-phase inverters

The number of variable-speed drives on modern machines is increasing steadily due to rising technological demands and the advent of advanced, economical converters. Today, these converters make use of pulse-width  modulation (PWM).

The course on self-commutated converters imparts a knowledge of topics ranging from DC voltage generation by means of PWM to vector modulation. Theoretical treatments and animation sequences are accompanied by experiments using real instruments. Topics include direct voltage generation using PWM, alternating and three-phase voltage generation, as well as vector modulation. FFT analyses permit evaluations of output signal quality.
This course is intended for use at vocational schools, universities and technical colleges.

  • Order number: SO4204-7M, consisting of
  • 1 x CD with course :Self-commutated converters�
  • 1 x Experiment card : Self-commutated converter�
  • 1 x Experiment card:  Load self-commutated converter�

Frequency-converter drives

  • Intermediate circuit
  • Inverters
  • Speed adjustment

Frequency converters permit low-loss and continuous adjustment of the speed of asynchronous three-phase motors. Modern frequency converters are microprocessor-controlled. Besides serving to control and protect motors, these devices also perform process automation functions nowadays.
Supplementing the courses on self-commutated converters and asynchronous machines, this course imparts a broad knowledge of the following topics:

  • Intermediate-circuit voltage
  • V/f characteristics, boost
  • Brake choppers
  • Speed ramps
  • 87-Hz operation

Theoretical treatments are accompanied by numerous experiments to consolidate the acquired knowledge.

BLDC motor & PFC
Brushless direct-current (BLDC) motor Operating similarly to synchronous motors, BLDC motors are used in a variety of areas and applications. The permanent magnet rotor follows the stator field without any slippage. As this motor's  distinguishing feature, the electronic commutation results in efficient and highly dynamic drives.
The course describes design of the motor and control electronics and their functions. Investigations cover the transmission system and, in particular, the motor's power supply. Finally, the course demonstrates
the assembly of a torque/ speed-controlled drive.
Power factor correction (PFC)
Every modern computer power supply unit is furnished with a power-factor correction mechanism. This is required, for instance, by European standards stipulating devices whose mains current consumption is not linearly proportional to the voltage must be equipped with power factor correction above a certain power classification.

This course provides a step-by-step explanation of the principle of power factor correction, as well as its types and applications, and compares it to conventional rectifier circuits. Several in-depth experiments and FFT-analyses complete the course.