With this equipment, the operation and the stationary operating behavior of a synchronous machine with a salient pole rotor are examined. The basic tests are divided into engine and generator tests. Numbers 1 to 10 are basic engine tests and numbers 11 to 20 are basic generator tests. The additional experiments are arranged in the order in which they were created.
The experiments are carried out using industrially manufactured machines. All test machines have a special base for connection to the machine testing system 0.3. With the machine test CASSY, all measured values of the AC machines are recorded. The measured values can be displayed directly on the built-in display as an individual value, a table of a series of measurements or a diagram. The measurements can be carried out without additional software; the measurement data can be saved locally on the device. The CASSY machine test records the characteristics of the test machines. The power supply for the test machines partly comes directly from the public supply network. Depending on the experiment, the generator operation of the synchronous machine takes place in the island network or on the interconnected network.
Learning objectives
- Protective measures and electrical safety
- Construction and commissioning of electrical machines
- Use of starter circuits
- Efficiency of the machine
- Assessment of characteristics of electrical machines
- Characteristic curves in generator operation
The main area of application of the synchronous machine is energy generation. It is also used as commutated synchronous machines in drive control. In recent years, the commutated synchronous machine has been used in e-mobility. The salient pole rotor generators are used in hydroelectric power plants and diesel generators, which require a high number of pole pairs at low speeds. The salient pole machine is not suitable for high speeds. The high centrifugal forces that act on the rotor winding can no longer be controlled.
Highlights
- To protect against overheating, the stator windings of the test machines are equipped with temperature sensors.
- In case of overheating, the machine testing system switches off the load of the testing machine, thereby maintaining air cooling. This prevents damage to the test machines.
- The test machines have a didactic clipboard with the winding diagram printed on it.
- All winding ends are led out to safety sockets (4 mm) on the terminal board.
- Computer-assisted measurement recording delivers meaningful measurement results.
- The arrangement of the 4 mm safety sockets corresponds to the standards for industrial motors.
Measurement and media system
Machine test CASSY
The machine test CASSY 0.3 can be operated quickly in all functions directly via the display, the rotary wheel and the buttons on the device. All settings and measurement results can be saved on the device and quickly accessed later or simply downloaded.
In addition, the machine test CASSY 0.3 can be fully controlled in real time via RJ45 Ethernet, W-LAN and USB-C interfaces.
These interfaces can be used by the following software:
- CASSY Lab 2 for drives and energy systems,
- MATLAB® and LabVIEW™
- Lab Docs Editor Advanced
The following integrated servers are available in the machine test CASSY 0.3 for the local media connection of at least four devices at the same time.
For more information, see the product data 7731901 Machine Test CASSY 0.3.
The equipment is equally suitable for student experiments in the laboratory with low voltage (230 / 400 V three-phase current) and with a mobile test stand - for teacher demonstrations in the classroom or lecture hall. The experiments are carried out interactively as a Lab Doc as an HTML file or as a PDF document.
The target group is commercial trainees and students majoring in electrical engineering. The course offers experiments at an intermediate level for vocational schools and at the same time allows the necessary insights into machine behavior for scientific interpretation in bachelor's training. Thanks to the media connection, the experiments are suitable for demonstration in the classroom or in a lecture hall.
There are even more advanced experiments with synchronous machines in the following configurations:
- E2.2.5.2 Full pole rotor
- E2.2.5.3 Multifunctional machine
- E2.6.2.4 AC servo with industrial separately excited synchronous machine
Topics synchronous motor
- Connection of a salient pole rotor
- Inrun with runner cage
- Start-up with pony motor
- Torque and load
- Start-up procedures for synchronous motors
- Efficiency in engine operation
Topics synchronous generator
- No-load characteristic
- Short-circuit characteristic
- Excitation of the synchronous machine
- Operating behavior
- Armature current and torque
- Synchronization and parallel switching
- Efficiency in generator operation
- V curve in generator operation
This document contains a table of contents and thus defines a course whose chapters can be freely navigated.
Each entry in the table of contents is a chapter of the course. The order of the chapters is determined by the table of contents. The first chapter is always the table of contents itself.
