Experience in using asynchronous turbogenerators in the power stations of Russia

Abstract

The results of experience in the industrial use of different types of asynchronous turbogenerators in the "Mosénergo" Company thermal electric power stations are presented. Their basic technical characteristics and features of the main and standby modes of operation are considered.Asynchronous machines, the theoretical foundations of which were laid by M. M. Botvinnik, have found practical application in electric power engineering. In the USSR and then in the new Russia, various types of asynchronous turbogenerators have been developed and introduced, namely, both with a symmetrical system of excitation windings, and with an asymmetrical system, including with a "weak controlling" excitation winding on the transverse axis of the rotor [1,2].The stator of the asynchronous turbogenerator is of the traditional type. Special measures are taken in its construction to eliminate overheating of the end zones when the generator is operating with a deep consumption of reactive power.The rotor of the generator has two excitation windings on the d and q axes, arranged over the circumference of the rotor at an angle of ÷ with respect to one another.The vector ("asynchronous") control principle is used for asynchronous turbogenerators, in which the controlling actions are produced along two channels in an orthogonal system of coordinates x, y, rotating with the synchronous frequency, with further coordinate transformation of the control signals to the rotor axes d and q, taking into account the current position of the rotor with respect to the reference vector of a synchronous system of coordinates (usually the voltage of the generator stator or the voltage of the power station buses).In general, an asynchronous turbogenerator can have a system of two unlike excitation windings (a and b), shifted along the circumference of the rotor with respect to one another by a certain electrical angle ÷. These windings can have a different number of turns W a and W b (different emfs) and nonidentical electrical parameters (resistances and leakage inductances). The angle ÷ between the windings lies in the range 0 -ð/2, depending on the construction (type) of the asynchronous turbogenerator. As the angle ÷ is reduced in the range ð/2 ³ ÷ > 0, the properties of the generator change and we can estimate a certain critical value of the angle ÷ = ÷ cr (approximately ð/6), for which these properties undergo qualitative changes.According to this criterion, asynchronous turbogenerators can be divided into three groups, -the first with ÷ = ð/2; -the second with ð/2 > ÷ > ÷ cr ; and -the third with 0 < ÷ < ÷ cr . The first group is the "classical" asynchronous turbogenerator with a symmetrical system of orthogonal windings. Typical representatives, possessing all the "classical" properties of asynchronous turbogenerators are the type ASTG-200 (made by "Élektrotyazhmash") and the type T3FA-110 (made by "Élektrosila"), which have been developed and are commercially available, and also the type T3VA-110, -220 and -320 turbogenerators (manufactured by "É...

Experience in the development and operation of asynchronized turbogenerators and condensers in the Russian Power System

“…Experience has shown that asynchronized turbogenerators are in demand in electric power systems and operate within wide range of voltage control, especially in the modes of deep reactive power consumption, which is not achievable by traditional synchronous turbine generators [1]. Voltage change in a wide range is characteristic for nonuniform load diagrams (large cities, industrial plants), as well as for electric power systems with a large number of high voltage cable lines.…”

Improving the Energy Efficiency of Pumped-Storage Power Plants

“…The studies conducted by the VNIIE (currently the R&D Center of FGC UES) made it possible to create, in cooperation with the Élektrotyazhmash (Kharkov) and Élektrosila (St. Petersburg) plants, asynchronized turbogenerators and condensers [6,7]. After manufacturing and commissioning the first-ever asynchronized generator at the Iova HPP in the 1960s [8], there were no further developments of asynchronized generators.…”