Compressor
Tester

DYNAMOMETER

Laboratory workstation for demonstrating engine type tests. An asynchronous motor fed by a frequency converter with a recuperation and braking unit serves as the load cell. The workstation contains a dynamometer, a speed sensor, a torque sensor and sensors for measuring voltage and current.

The measurement of mechanical and electrical quantities is realized with NI DAQ cards in the cDAQ chassis. The sampling frequency of analogue signals is 10 kS/s. Inverter and technology control using the Simatic PLC.

The tests can be extended, include the measurement of winding resistance, temperature and vibration.

The device can be supplied with a static power supply with 3 phases, 1 phase and DC output.

SW APPLICATIONS

SW development by ELCOM. Application enables the control and parametrization of tests. Allows saving the results of all tests and graph display.

Modifications in power, voltage ranges, current, torque and mechanical design are available upon customer request.

AUTOMATIC TESTS

Aplikace pro robotizovaná pracoviště:

• Heating characteristics – measurement of motor and ambient temperature with thermocouples (type J, T), PT100, KTY
• Cooling test – temperature measurement – winding resistance measurement during cooling
• Torque test – at constant voltage – at constant torque – dynamic test
• Short circuit test with shaft interlock – the test can be performed quickly (approx. 2 s) even at nominal voltage
• Idle test

GENERAL TEST

• Arbitrary control of dynamometer and power supply

METROLOGY PARAMETERS

Current measurement

• Range 40 A
• DC frequency – 20 kHz
• Accuracy 0,5 %

Voltage measurement

• Range 600 V
• DC frequency – 20 kHz
• Accuracy 0,5 %

Torque measurement

• Range 17,5 Nm
• Accuracy 0,5 %

DYNAMOMETER PARAMETERS

Current measurement

• Nominal power – 4 kW
• Maximum speed – 6000 rpm.
• Nominal torque – 9 Nm
• Maximum torque – 15 Nm
• Integrated speed sensor 1024 imp./rev.
• Frequency inverter Sinamics S120

General information

ELCOM, a. s., ranks among the leading Czech providers for testing of electrical machinery. Significant customers include Siemens branches in Mohelnice and Frenštát in the Czech Republic.

Our company provides complete hardware and software for testing including power supplies, dynamometers, measuring equipment, control software, test benches, etc. Testing allows the implementation of standardized and experimental tests of engines of power in the megawatt range. Construction of testing is done on a project by project basis taking into account the specific requirements of our customers, so it is a custom implementation built to order. When designing the test facility we use proven electrical circuit designs, our special test power supllies and we have developed test software and some special electronic components.

In addition to complete testing facilities ELCOM, a. s., also supplies individual parts or engine testers and their parts, which cover only some of the tested parameters.
We can provide the following typical configurations of testing machines and their parts:

• Tests of the input material
• In-process tests/Interoperation tests
• Final inspection tests
• Testing for type tests
• Laboratory for experimental tests
• Inter-turn short circuit testers
• Partial discharge test

Why we are unique

Special features of electrical motor testing equipment from ELCOM, a. s. include:

• Utilization of an in-house designed power supply, which can fulfill any test engine operating conditions and some special dynamic operations
• Utilization of in-house designed and continually updated software for the control of the test equipment, but also for the evaluation of measured values ​​according to a series of standards that govern the testing of asynchronous motors
• Installation of heavy infrastructure including main feeder cable, rack configuration, management of cable trays or in the channels, all our own staff with experience in the field of constructing testing facilities

Overview of tests

Architecture

Test power supplies

These test power supplies are provided as kits containing switchgear control resources, power switching devices, the step-up transformer and other components.

Parameters of test power supplies:

• Umax = 10 kV
• Smax = 1,5 MVA
• F max = 400 Hz
• THD < 2 %
• Independent control of U, I, f
• Built-in functions U ramp, I ramp, frequency ramp
• Electronic protection
• Output transformer to change the voltage levels

Transducers for measuring electrical quantities

Voltage and current transducers provide oscilloscope data at a sampling rate of tens to hundreds of kHz.
Isolation barriers for safe separation of the product tested by the measurement system.

Transducers for the measurement of non-electrical quantities.

Transducers include temperature sensors, torque sensors, vibration sensors, microphones, thermal imagers. The measuring system records the test signals in the form of sampled data with a sampling frequency of up to tens of kHz, and performs subsequent processing.

Measurement and Control System

The measurement and control system is based on the hardware and software from National Instruments. The control functions are implemented using the Compact RIO, measurement functions using the multifunction measuring cards, data analysis and control graphical user interface is implemented using a powerful industrial PC.

Software for managing, measuring and processing of data is developed in LabVIEW from National Instruments.

Datalogging

During measuring a record is kept of all measured data in raw form in TDMS format. The stored data is then processed by applications for the evaluation of testing engines that combine data, perform calculations, compare with selected standards and generates an output protocol. Data TDMS format is readable by a commercial reader that is part of the universal data management and processing DIADEM from National Instruments.

Postprocessing data

Software testing equipment includes applications for processing the raw measurement data. The application allows presetting of data processing including the choice of standards according to which the processing takes place. In addition to the standard built-in signal processing such as determining the efficiency of an engine, it is possible to perform their own analysis aimed at identifying specific phenomenon. An example would be the detection of fast power oscillations with time resolution of only a few periods of the motor power supply.

Configuration circuits (docking)

Configuration circuits consist of a matrix of contactors which allow mutual switching sources, measuring instruments and test engines in manual or automatic mode for selected tests. These circuits can be dimensioned up to 15 kV and 10 kA.

Test bench

Test benches for the location and positioning of the engine under test and load factor by axial height are produced as solid welded frames with mounting plates provided with dovetail grooves. Movements in the vertical direction can be controlled electrically.

Load factor

Loading of the test engine is done through a combination of electrical load machines and frequency convertors. In synchronous generators set inductors are used as the load factor or active load in the form of a frequency converter supplying reactive power.