Evaluating the Efficiency of the Classic Adjustable-Frequency Induction Motor Control Laws
Abstract
Adjustable-frequency induction motor-based drives occupy the dominating place among adjustable electric drives. Therefore, it is important to consider rational methods for controlling induction motors (IMs) from the viewpoint of decreasing their energy consumption. There are two such control methods: using the proportional law of controlling the motor power supply frequency and voltage and using the law that maintains constant stator and rotor flux linkages and the main flux linkage in the air gap. A procedure for calculating the power performance indicators of an adjustable-frequency IM for these control laws is proposed, using which they can be calculated and compared in a relatively simple manner without iterations. The calculation formulas used in the procedure are based on the system of vector equations for a steady-state operation mode and on the equivalent circuit drawn from these equations. An example of calculating the indicators of induction motors with the capacity P2 = 15 kW during their operation with a constant torque in the specified range of rotation frequencies is given. The results from calculating the motor power performance indicators during motor operation with a constant torque and with decreasing the power supply voltage have shown that the control law maintaining a constant rotor flux linkage yields higher values of the efficiency and power factor. It is exactly this law that is more preferable for use in the adjustable-frequency drive control systems.
References
2. Мальцев А.Н., Хватов О.С. Определение энергоэффективных режимов работы насосных агрегатов с частотно-регулируемым электроприводом на канализационных станциях. — Труды Нижегородского технического университета им. Р.Е. Алексеева, 2017, № 4 (119), с. 100—107.
3. Попов А.Н., Сайфутдинов В.Б. Частотное регулирование асинхронного двигателя при постоянной мощности. — Известия вузов. Проблемы энергетики, 2006, № 1—2, с. 46—58.
4. Космодамианский А.С., Воробьев В.И., Пугачев А.А. Моделирование электропривода с асинхронным двигателем в режиме минимума мощности потерь. — Электротехника, 2012, № 12, с. 26-31.
5. Островлянчик В.Ю., Поползин И.Ю. Исследование магнитной системы асинхронного двигателя при частотном управлении. — Вестник Кузбасского государственного технического университета, 2016, № 2(114), с.75—84 .
6. Браславский И.Я., Ишматов З.Ш., Поляков В.Н. Энергосберегающий асинхронный электропривод. М.: Издательский центр «Академия», 2004, 256 с.
7. Соколовский Г.Г. Электроприводы переменного тока с частотным регулированием. М.: Издательский центр «Академия», 2006, 272 с.
#
1. Malgin G.V., Bespalov A.V. Dinamika sistem, mekhanizmov i mashin — in Russ. (Dynamics of systems, mechanisms and machines), 2014, No.1, pp. 307—310.
2. Maltsev A.N., Khvatov O.S. Trudy NGTUim. R.Ye. Alekseyeva — in Russ. (Proceedings of the NSTU. R.E.Alekseyev), 2017, No. 4(119), pp.100—107.
3. Popov A.N., Saifutdinov V.B. Izvestiya vuzov. Problemy energetiki — in Russ. (News of higher educational institutions. Problems of Energy), 2006, No. 1—2, pp. 46—58.
4. Kosmodamiansky A.S., Vorobev V.I., Pugachev A.A. Elektrotekhnika — in Russ. (Electrical Engineering), 2012, No. 12, pp. 26—31.
5. Ostrovlyanchik V.Yu., Popolzin I.Yu. Uestnik Kuzbasskogo gos. tekhn. universiteta — in Russ. (Bulletin of Kuzbass State Technical University), 2016, No. 2(114), pp.75—84.
6. Braslavsky I.Ya., Ishmatov Z. Sh., Polyakov V.N. Energosberegayushchii asinchronyi electroprivod. (Energy saving asynchronous electricdrive). Moscow, Publishing Center «Academy», 2004, 256 р.
7. Sokolovsky G.G. Electroprivody peremennogo toka s chastotnym upravleniyem (AC drives with frequency regulation). Moscow, Publishing Center «Academy», 2006, 272 p.