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A classical example of such kind of machine is three phase asynchronized turbogenerator (ASTG) with two phase symmetrical excitation winding sup plied from a source with controllable amplitude and phase of output voltage at a phase shift by π/2 [1]. Excitation windings are supplied by a system of auto matic excitation current control that implements the asynchronized principle of excitation control [2,3], at which the changes mentioned above transform from synchronous rotation axes to geometrical rotor axes. At the same time, one channel controls the level of the electromagnetic moment in the function of loading angle δ and the second regulates voltage in a controlled point of the system. The possibility of controlling elec tromagnetic moment value in dependence on angle δ takes off the concept of static stability in function of loading angle.In ASTGs, excitation windings are supplied in steady modes by zero frequency voltages.The described ASTG ideology is used in the ASTGs with full air cooling elaborated and released by Electro sil in 2003. A 110 MW generator (T3FA 110 2U3, 10.5 kV, cosϕ = 0.95) [4,5] has two big windings on the rotor shifted along the rotor circumference by 90°. Hav ing been successfully exploited since 2003 in the Mos cow power system, ASTG confirmed the forecasted operating characteristics [6]. The main advantages of an ASTG over a synchronous generator are as follows: abil ity to work in modes of the deep consumption of reac tive power with the possibility of unloading form the functions of generators operating in parallel; increasing of the quality of dynamic process flows in the generator itself and the environment of the connected system; and increasing the reliability of the ASTG at the expense of its unlimited operating with one excitation winding in synchronous mode in the power diagram range of P = 105 MW, Q = 0 to P = 110 MW, Q = -35 MVA [5] or in asynchronous mode with short circuited excitation windings and simultaneous loading to 80 MW of active and -85 MVA of reactive power while maintaining the rated voltage on its wires [6]. The listed properties of ASTGs are due to the rotating magnetic current of the excitation winding regarding to the rotor body and are achieved in a system of automatic excitation winding current control.The appendix contains the main properties of all projects and samples of ASTGs (made by Electrosil) mentioned in the abstract. Based on the results of developing a T3FA 110 2U3, 160 MW ASTG, which is a project with a similar system of excitation windings (Fig. 1) and full air cooling, T3FA 160 2U3 (U = 15.75 kV, cosϕ = 0.95) was created [5]. The power of Abstract-Designs of a fully air cooled 110 and 160 MW ASTG with two similar excitation windings and cosϕ = 0.95 are observed. A prototype has been created for a 110 MW ASTG that has been in operation since 2003. Prototypes for a 320 MW ASTG with asymmetrical windings on a rotor is developed and a 100 MVA asynchronized controlled compensator (ASKU) is developed.

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Translated from Élektricheskie Stantsii, No. 11, November 2008, pp. 62 -65. The fundamental parameters and construction of asynchronous compensators, soon to be produced by the "Silovye Mashiny" -"Élektrosila" Joint Stock Company in 2008, are considered. The compensator has a massive nonsalient-pole rotor with two excitation windings, shifted by 90°(in electrical angles), supplied from controlled reversible power sources. The compensators provide delivery-consumption of reactive power in the ±100 Mvar range with the possibility of short-term double forcing of the power output and improved dynamic characteristics compared with synchronous compensators.One of the most important problems in electric power engineering is providing regulation of the reactive power in the electric network. In addition to modes of operation that require reactive power output by the generator, including forced output during short emergency operation, modes of operation are also possible in which it is necessary to consume this power. Examples are as follows: when transmitting electric power along long lines, when transferring local electric supply networks from overhead lines to cable lines, when there is a considerable periodic variation over time of the active power consumed from the network, and in order to reduce thermal loads on the elements in the end zone in parallel with the working synchronous turbogenerators. One of the means of eliminating both the deficiency and the excess of reactive power is to establish electrical-machine reactive power compensators at the network junctions, which provide regulation of the reactive power over a wide range.Electrical machine compensators, unlike static compensators, based on modern power electronics, do not introduce distortions into the current and voltage curves of the system and improve the dynamic processes in the network due to the effect of the rotating masses of the compensator. Electrical machine compensators enable one to increase the production of reactive power under dynamic conditions briefly up to twice the nominal value.The nominal power of a synchronous compensator is determined by the value of the maximum possible reactive power that can be produced by the compensator over a long period. The limiting consumed reactive power for a salientpole synchronous compensator when there is no possibility of negative excitation is about 50% of the reactive power produced by the compensator and does not exceed 80 -85% of the power produced when there is a compensator in the system with possible negative excitation. These relations are even less for a nonsalient-pole synchronous compensator. Hence, up to the present time salient-pole synchronous compensators have been used in practice.The application of modern principles of asynchronous control of synchronous machines to electrical machine compensators [1 -3] enables the compensator to operate in its nonsalient-pole form when the limiting values of the produced and consumed reactive power are equal. For this to occur the compensator mu...