SU1663721A1 - Three-phase static ferromagnetic frequency tripler - Google Patents

Abstract

The invention relates to electrical engineering and can be used to power electrical consumers, such as electric motors, with a voltage of three times the voltage. The purpose of the invention is to simplify the design and manufacturing technology, as well as increase reliability. The active part of the device consists of three identical modules, including a reduced number of primary coils. On the cores of each of the three groups of O-shaped cores 1-9, there are coils W _b and W _{m of} one phase of the primary winding and two coils W _with and W _from two other different phases of this winding, as well as coils W _{2 of the} secondary winding. When the primary winding is connected to a three-phase system of fundamental frequency voltages and a deep magnetic saturation of the rods of the magnetic system, a three-phase symmetric system of almost sinusoidal voltages of tripled frequency will be removed from the terminals of the secondary winding. 3 il.

Description

The invention relates to electrical engineering and can be used as a power source with a voltage of three times the frequency.

The aim of the invention is to simplify the design and manufacturing technology, as well as increase reliability.

FIG. 1 schematically depicts a magnetic system with three-phase primary windings located on its rods (the beginning of the phases is denoted by the symbols Ai, Bi, Ci) and the three-phase secondary winding (A2, Ba, Ca); in fig. 2 - three-phase symmetrical star of nine vectors - magnetomotive forces (m, dc) of rods; in fig. 3 - vector diagram of the third harmonic of the magnetic flux.

The indices, numerals, and letters in FIG. 2 and 3 correspond to the accepted symbols in FIG. one.

The proposed frequency triple consists of a magnetic system and three-phase primary and secondary windings, respectively, fundamental and tripled frequencies. The magnetic system is made in the form of the same three groups of 0-shaped hearts. nobody 1-9, three symmetrically arranged cores in each group, with three cores of these contacting coresOs

WITH

CO VI

Yu

and are located in the center of the group (central rods), and the other three rods of the same group are mutually offset by 120 ° and are located on the periphery of the core group (peripheral rods). Each phase of the primary winding of the main frequency consists of four (We - with a large number of turns, WM - a small number of turns and two Wc - with an average number of turns) of successively connected coils, the ratio of the number of turns of which is We: WM: Wc: Wc 1: 0.347: 0.532: 0.532. Four primary coils are located on the rods of each group of 0-shaped cores, the central rods encompass We of this phase, and one of the peripheral rods is covered by the WM coil of the same phase, the second peripheral rod is covered by the Wc coil of another phase, and the third peripheral rod is covered coil Wc third phase. Each phase of the triple frequency secondary winding consists of three in series according to the connected W2 coils, each comprising one of the three peripheral rods (Fig. 1) or central rods belonging to three separate groups of 0-shaped cores. The turns of each coil of the secondary winding can be divided into two parts, one of which is placed on the peripheral one and the other on the central core of this conformable core.

The 0-shaped core can be made twisted uncut, or twisted cut or laminated. The 0-shaped core can be wound from electrical steel tape not only of constant width, but also of variable width, just as it is done at electrical plants producing power transformers with a spatial magnetic core consisting of three twisted uncut 0-shaped cores. With a corresponding width of electrical steel strip, the filling of the coil cavity with the number of turns We is improved by the steel. If the 0-shaped core is twisted, then the planes of the two cuts, one cut across the rod, can either be perpendicular to the axis of the rod, i.e., the magnetic field lines, or these planes can have other inclinations to this axis. In this latter case, the cross-section of the gap-joint increases, and the magnitude of the magnetic induction in it decreases, which leads to a decrease in magnetic losses in the region of the gap-joint.

Thus, the active part of the frequency tripler consists of three identical modules.

The operation of the proposed frequency generator is based on the magnetic saturation of the rods of the magnetic system of the first harmonic of the magnetic field induction, which is due to the system p. (F vectors in FIG. 2) created by the fundamental frequency current fi,

0 flowing in the primary winding. Due to the nonlinearity of the magnetization curve of the steel of the magnetic system, the magnetic field induction curve will contain a spectrum of odd time harmonics. Of

The 5 highest harmonics of the highest amplitude will have a third harmonic of the magnetic flux Φ (Fig. 3), which will determine the three-phase symmetric voltage U2 of a tripled frequency almost sinusoidal

0 forms on terminals Aa, B2, C2 of the secondary winding. Magnetic flux harmonics of orders 6.K ± 1, where K 1, 2, 3 are not

cause the resulting voltage in the phases of the secondary winding, as in

5 three coils of each phase of this winding, they induce EMF mutually shifted in time by 120 °. Magnetic flux harmonics of the order 9.K, where K 1, 3, 5, ... does not cause a voltage across the terminal of the A2, B2, or C2 secondary winding, since these harmonics have zero phase sequence. Only the 15th harmonic of the magnetic flux induces a negative-sequence emf in the secondary circuit, but the amplitude of this harmonic is negligible.

The current flowing in the primary winding of the proposed triple is practically sinusoidal, i.e., essentially does not contain 3,

0 5, 7, 9, 11, 13, 15th harmonics. This is due to the accepted ratio of the numbers of turns of the primary coils and the diagrams of their connection and location on the rods of the magnetic system.

five

Claims (1)

Claims of the Invention Three-phase static ferromagnetic frequency tripler containing a magnetic system including three groups 0 0-shaped cores, three cores in each group, on the rods of which are placed connected to the input terminals for connecting the supply network of the coil of the three-phase primary winding 5 main frequencies interconnected according to a scheme that creates a symmetric three-phase-split system of nine vectors of magnetomotive forces of rods and connected to a star, the ends of which are connected to the output terminals for connecting the load, coils of three-phase secondary winding of triple frequency, connected in each phase in series, characterized in that, in order to simplify the construction and manufacturing technology, as well as to increase reliability, each phase of the primary winding consists of four coils with a ratio of the numbers of tkov equal to 1: 0.347: 0.532: 0.532, with three 0-shaped cores within each group of cores are located symmetrically relative to each other so that the three cores of these cores are in contact and located in the center of the group, and Peripherals rod l0 the other three rods of the same cores are mutually offset by 120 ° and are located on the periphery of a group of cores; in each phase of the primary winding a coil with a large number of turns covers three rods of the corresponding group located in the center of this group, a coil with a smaller number of turns of the same phase on one of the peripheral rods of the same group, and two coils with an average number of turns of the same phase are located one on one of the peripheral rods of the other two groups of cores of the magnetic system. Stump resulting in May. s-toO-oSpoiHoto ft, core - Index corresponds to vte coil Fa G. 2 Fig. / core f-to o-offpoitMito Mdc hand resist vector % PI-CuftSoMi pca / J LMotiep 0-o & azno core Ze tor cutting kak. G-to O-ozroz about the core Vi FZ SHZ L-Noner O- oSpoyffoeo Serdemika Vj Fb