Testing the motors with "Slavyanka" at University Düsseldorf

We continue the topic of the tests with the modified motors held by Victor Arestov since 2013.
Two tests were held at University Düsseldorf.
The first test of a 5kW motor was held on request of CG Global group of companies. The rotor was rewound to 690 V while the testing equipment was limited to 400 V. After supplying it with a transformer, the voltage was increased up to 500 V and the testing was held. The original motor performance parameters weren't measured, we used the factory performance figures as reference.
Slavyanka showed the drop of the efficiency after 40 % load.
After the observed results of 500 V test, we decided to conduct comparative testing of the original and modified 7.5 kW motors.
We first tested the original and then the "Slavyanka" rewound original.

Right there at University Düsseldorf one year later on request of SPBEC, testing of two Siemens motors was held to prove they could be improved as well.

Apart from the tests at the Universities of Bologna and Düsseldorf, the comparative test of 200 V motors for food industry was held in Germany. We have already posted information about this test.
The commissioning client of this research stated the previously observed motor overheating and jamming at pressing.
The task was to modernize two motors using "Slavyanka": one motor with the same power but smaller current, the second motor - wound for increased power.
After the final tests, the customer chose the increased power motor that operated faultlessly further on.
The protocols with the results of the held tests are available here - https://drive.google.com/open?id=1rjDvqU6SigjxEWOYczc0HJv3P9DpGkgb

The held tests demonstrated considerable improvement of the torque and efficiency of the motors with "Slavyanka", especially at low load and load higher than nominal. The motors with "Slavyanka" endure almost the double load.

The original source of the information about the tests held by Victor Arestov on the forum "Electrotransport.ru" in Russian can be found here - https://electrotransport.ru/ussr/index.php?topic=43516.msg1057279#msg1057279