RU2396625C1 - Transformer - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: transformer includes flat four-pin magnetic conductor the section area of end pins of which is twice as small than the surface area of the pins located between them. Each pin is enveloped with similar primary winding and a group of secondary windings. Windings enveloping one end pin are connected in series and in keeping with similar windings enveloping the other end pin. Group of secondary windings includes two opposite secondary windings with number of loops Nk₀, two secondary windings with number of loops Nk₁ and two like opposite secondary windings, two secondary windings with number of loops Nk₂ and two like opposite secondary windings, two secondary windings with number of loops Nk₃ and two like opposite secondary windings, where: N - maximum number of loops, and k₀=1, k₁=(1+1/3^1/2)/(2cos15°), k₂=1/3^1/2, k₃=1/(2·3^1/2cos15°). Each secondary winding wound in keeping with or opposite one pin is consequently connected to the secondary winding of the other pin and to the secondary winding of the third pin, thus forming zigzag connection the free outputs of which are outputs of transformer.

EFFECT: simplifying the construction and improving reliability.

4 dwg, 1 tbl

Description

The invention relates to electrical engineering, namely, to electromagnetic transformers.

Known three-phase transformer Dolivo-Dobrovolsky, which contains a spatial magnetic circuit, consisting of three rods, clamped by two yokes and located at equal distance from each other perpendicular to the plane of these yokes; moreover, each rod is covered by one primary and one secondary winding (Kostenko MP and other Electric machines. M.-L.: Energy, 1969, S.364). The transformer is characterized by phase symmetry, however, it is not designed to receive a multiphase output voltage and has a complex magnetic circuit.

Known phase-symmetric transformer, designed to convert three-phase voltage into multiphase, the magnetic circuit of which contains rods clamped by two yokes and located at an equal distance from each other perpendicular to the plane of these yokes; moreover, the number of rods is equal to the number of phases of the output multiphase voltage, each rod is covered by one secondary winding, and three rods equally spaced from each other have one primary winding (patent of the Russian Federation No. 2125749 C1, IPC Н02М 5/04, 1997). However, the transformer magnetic circuit has low strength and complex construction.

Known transformer Trihal, which contains: a flat magnetic circuit, consisting of three parallel rods located between two yokes; primary and secondary windings that cover these rods (Dry transformer with cast insulation Trihal. - TRIHALCATRU. - www.schneider-electric.com. MV / LV Transformers Trihal. - 06/2006, 16 pp.). The transformer magnetic core has a simple flat design. However, in this magnetic circuit, the length of the length of the yoke connecting the extreme rods is greater than the length of the length of the yoke connecting the extreme rod located in the middle of the magnetic circuit. It is not possible to compensate for the resulting difference in the inductance of the windings covering the rods located along the edges and in the middle of the magnetic circuit. Therefore, the disadvantage of the transformer is the lack of phase symmetry. The phase asymmetry of transformers excludes the possibility of their use, for example, for the formation of multiphase voltages.

The closest in technical essence is a multiphase power supply containing a transformer and a rectifier with n inputs connected in series (Kazakov V.V. Power MTS transformers and generators. Power engineering of Tatarstan. - K, 2007. - No. 3. - P.44-55 - prototype). The source transformer contains a spatial magnetic circuit consisting of three rods clamped by two yokes and located at equal distance from each other perpendicular to the plane of these yokes; moreover, each rod is covered by the same primary winding and a group of secondary windings, which contains two counter secondary windings with the number of turns Nk ₀ - windings of the main output phases a, i, q, coinciding with the input phases A, B, C, two secondary windings with the number of turns Nk ₁ and two of the same oncoming secondary windings, two secondary windings with the number of turns Nk ₂ and two of the same oncoming secondary windings, two secondary windings with the number of turns Nk ₃ and two of the same oncoming secondary windings, where: N is the maximum number of turns, k is the coefficient of chi la turns, where k ₀ = 1, k = ₁ (1 + 1/3 ^{1/2) / (2cos15 °),} k ₂ = 1/3, ^1/2, k ₃ = 1 / (2 · 3 ^1/2 cosl5 °). In this case, one secondary winding with the number of turns Nk _{1 of the} first rod is connected in series with the oncoming secondary winding with the number of turns Nk _{3 of the} second rod, and the second one with the same winding of the third rod facing it, one secondary winding with the number of turns Nk _{1 of the} second rod is connected in series a secondary winding wound counter s to Nk number of turns of the first rod ₃ and the second - with the same winding counter to it the third rod, one secondary winding with the number of turns of the third rod Nk ₁ is connected in series with the secondary bmotkoy counter her winding the number of turns Nk ₃ of the first rod and the second - with the same counter her winding of the second web similarly connected other colliding secondary winding bars with the number of turns Nk ₁ and Nk _3, one secondary winding with the number of turns Nk ₂ the first rod connected in series with the secondary winding of the counter winding with the number of turns Nk _{2 of the} second rod, and the second one with the same counter winding of the third rod, one secondary winding with the number of turns Nk _{2 of the} second rod is connected in series with the secondary one counter winding with the number of turns Nk _{2 of the} first rod, and the second with the same counter winding of the third rod, one secondary winding with the number of turns Nk _{2 of the} third rod is connected in series with the secondary winding of the counter winding with the number of turns Nk _{2 of the} first rod, and the second with the same winding of the second rod she meets, forming a zigzag connection. The free terminals of the zigzag connections and the free terminals of the secondary windings with the number of turns Nk ₀ are the outputs of the transformer, and in each zigzag connection the coefficient k ₁ , k ₂ or k ₃ and the direction of winding of these windings, as well as the coefficient k ₀ and direction of winding the windings of the main output phases a, i, q provide the same amplitude of the output linear voltage of the transformer and their sequential delay by 15 ° relative to each other. However, the source transformer has a spatial, hence complex, magnetic circuit.

The objective of the invention is to simplify the design of the transformer and increase reliability.

The technical result is achieved by the fact that in a transformer containing a core magnetic core, clamped by two parallel yokes, each rod is located at an equal distance from each other and is covered by the same primary winding and a group of secondary windings, which contains two counter secondary windings with a number of turns Nk ₀ , two secondary windings with the number of turns Nk ₁ and two identical secondary windings, two secondary windings with the number of turns Nk ₂ and two similar secondary secondary windings, two secondary windings with the number of turns in Nk ₃ and two similar secondary windings, where: N is the maximum number of turns, and k is the coefficient of the number of turns, and k ₀ = 1, k ₁ = (1 + 1/3 ^1/2 ) / (2cos15 °) , k ₂ = 1/3 ^1/2 , k ₃ = 1 / (2 · 3 ^1/2 cosl5 °), while one secondary winding with the number of turns Nk _{1 of the} first rod is connected in series with the oncoming secondary winding with the number of turns Nk ₃ the second rod, and the second - with the same winding counter to it the third rod, one secondary winding with the number of turns of the second rod Nk ₁ is connected in series with the secondary winding counter winding it with the number of turns of the first Nk ₃ terzhnya, and the second - with the same counter her winding of the third rod, one secondary winding with the number of turns Nk _one third of the rod is connected in series with the secondary winding counter her winding the number of turns Nk ₃ of the first rod and the second - with the same counter her winding of the second of the rod, similarly the other counter secondary windings of the core magnetic circuit with the number of turns Nk ₁ and Nk ₃ are connected, one secondary winding with the number of turns Nk _{2 of the} first rod is connected in series with the secondary winding of the counter winding with the number of windings weights Nk _{2 of the} second rod, and the second with the same winding of the third rod, one secondary winding with the number of turns Nk _{2 of the} second rod is connected in series with the secondary winding of the opposite winding with the number of turns Nk _{2 of the} first rod, and the second with the same counter shaft third winding it one secondary winding with the number of turns Nk third rod ₂ is connected in series with the secondary winding counter winding it with the number of turns Nk ₂ of the first rod and the second - with the same winding counter to it a second rod forming a soy Inonii "zigzag" free terminals which, as well as secondary windings to the number of turns Nk ₀ form a sequence multiphase transformer outputs magnetic transformer is flat chetyrehsterzhnevym, wherein the sectional area of outer rods half square rods disposed therebetween, all winding covering one extreme rod, connected in series and in accordance with the same windings spanning the other extreme rod.

The table shows the groups of secondary windings connected in a zigzag circuit.

Table Output phase The number of turns in the winding of group 13 and the number of turns in the winding of group 16 The number of turns in the winding of group 14 The number of turns in the winding of the group 15 a N k ₀ , N k ₀ - - b N k ₁ , N k ₁ - -N · k ₃ from N k ₂ , N k ₂ - -N · k ₂ d N · k ₃ , N · k ₃ - -N · k ₁ e - - -NK ₀ f - N · k ₃ -N · k ₁ g - N k ₂ -N · k ₂ h - N k ₁ -N · k ₃ i - N k ₀ - j -NK ₃ , -NK ₃ N k ₁ - k -NK ₂ , -NK ₂ N k ₂ - l -NK ₁ , -NK ₁ N · k ₃ - m -NK ₀ , -NK ₀ - - n -NK ₁ , -NK ₁ - N · k ₃ o -NK ₂ , -NK ₂ - N k ₂ p -NK ₃ , -NK ₃ - N k ₁ g - - N k ₀ r - -N · k ₃ N k ₁ s - -N · k ₂ N k ₂ t - -N · k ₁ N · k ₃ u - -NK ₀ - v N · k ₃ , N · k ₃ -N · k ₁ - w N k ₂ , N k ₂ -N · k ₂ - x N k ₁ , N k ₁ -N · k ₃ - The sign "-" means the opposite direction of the winding

Figure 1 presents a General view of the transformer, figure 2 - the magnetic circuit of the transformer, figure 3 - connection diagram of the transformer windings to obtain a multiphase voltage, for example, 24-phase, figure 4 - design of a flat magnetic circuit, consisting of a set O -shaped cores, the connection between which is provided by a common group of windings or by sequential inclusion of the windings of these rods.

The transformer contains a flat magnetic circuit 1, consisting of four parallel rods 2, 3, 4, 5 of the same length and yoke 6, 7; primary windings 8, 9, 10, 11, and the primary windings 9 and 10, covering the rods 3 and 4, belong to two phases B to C of the input three-phase voltage; windings 8 and 11, covering rods 2 and 5, are connected in series with each other and belong to the third phase A of the input voltage; identical groups of secondary windings 12, 13, 14, 15, and groups 13 and 14, covering the rods 3 and 4, relate to the two main phases i and q of the output voltage, coinciding with the input phases B and C; each winding of group 12 is connected in series with an identical winding of group 15; groups of windings 12 and 15, covering rods 2 and 5, belong to the third main phase and the output voltage, which coincides with the input phase A. Each of the groups 12, 13, 14 and 15 contains two counter windings with the number of turns N · k ₀ , two windings with the number of turns N · k ₁ and two same counter windings, two windings with the number of turns N · k ₂ and two same counter windings, two windings with the number of turns N · k ₃ and two similar counter windings. A sequence of multiphase outputs, e.g. a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x of transformer 1 is formed by the leads of the secondary windings with the number of turns N · k ₀ , the free leads of the zigzag connections of the oncoming windings with the number of turns N · k ₁ and N · k _{3 of} different groups: 13 and 14; 13 and a consonant compound of groups 12 and 15; 14 and the consonant connection of groups 12 and 15, as well as the free leads of the zigzag connections of the counter windings with the number of turns N · k _{2 of} different groups: 13 and 14; 13 and a consonant compound of groups 12 and 15; 14 and a consonant compound of groups 12 and 15.

The transformer operates as follows.

Sine-wave symmetric three-phase mains voltage, i.e. the voltage consisting of linear components A, B, C (Fig. 3), which have the same amplitude U _A = U _B = U _C and a phase shift of 120 ° relative to each other, is applied to the same primary windings 9, 10 and series-connected primary windings 8 and 11. In secondary windings having a maximum number of turns equal to N · k ₀ and belonging to groups 13, 14, a series connection of groups 12, 15 induces a symmetric EMF consisting of linear components of the main phases a, i, q of the output voltage, which have the same amplitude U = U _a = U _b = U _c , i.e. coincide in phase with the input voltages A, B, C, having a phase shift of 120 ° relative to each other. In the zigzag connections of the remaining secondary windings having a smaller number of turns N · k ₁ , N · k ₂ , N · k ₃ , derivatives of the output voltage phases are formed, for example, b, c, d, e, f, g, h, j, k, l, m, n, o, p, r, s, t, u, v, w, x, which have the same amplitude U but are 15 ° out of phase with respect to the three main output phases (a, i, q) and relative to each other.

Any change in the magnetic flux in the rod 2 of the magnetic circuit causes a proportional change in the EMF and currents in the series-connected primary windings 8 and 11, as well as in the series-connected secondary windings of groups 12 and 15, which leads to a proportional change in the magnetic flux in the rod 5. Therefore, the connection of the rods 2 and 5 through the same primary windings 8 and 11, as well as through the same secondary windings of groups 12 and 15, is equivalent to the full magnetic coupling of the rods 2 and 5. Due to the same number of turns of the windings covering all rods, but half the cross section of the extreme rods, the inductance of the windings covering the rods 3 and 4 is equal to the inductance of the windings covering the rods 2 and 5. Therefore, the transformer 1 is phase-symmetric.

The proposed technical solution allowed to simplify the design of the transformer, and symmetry is a condition for high-quality rectification of multiphase voltage.

Flat magnetic core can be made in the form of a set of O-shaped rings (figure 4). It is equivalent to the structure depicted in figure 2, and it can be conditionally divided into rods 2, 3, 4, 5 and yoke 6 and 8.

The introduced connection of the extreme rods by sequentially connecting the same windings that cover these rods is equivalent to the fusion of these rods, therefore replacing their magnetic connection, providing phase symmetry of the transformer.

Claims (1)

A transformer containing a core magnetic core, clamped by two parallel yokes, each rod is located at an equal distance from each other and is covered by the same primary winding and a group of secondary windings, which contains two counter secondary windings with the number of turns Nk ₀ , two secondary windings with the number of turns Nk ₁ and two counter same secondary winding, two secondary windings with a number of turns Nk ₂ and two counter same secondary winding, two secondary windings with a number of coils ₃ and Nk are the same two opposing secondary winding Where N - maximum number of turns, k - the coefficient of the number of turns, wherein k ₀ = 1, k = ₁ (1 + 1/3 ^{1/2) / (2cos15 °),} k ₂ = 1/3 ^1/2, k ₃ = 1 / (2 · 3 ^1/2 cos15 °), while one secondary winding with the number of turns Nk _{3 of the} first rod is connected in series with the counter secondary winding with the number of turns Nk _{3 of the} second rod, and the second with the same opposite winding third rod, one secondary winding with the number of turns of the second rod Nk ₁ is connected in series with the secondary winding counter winding it with the number of turns Nk first rod ₃ and the second - with the same winding counter to it th third rod, one secondary winding with the number of turns Nk _one third of the rod is connected in series with the secondary winding counter her winding the number of turns Nk ₃ of the first rod and the second - with the same counter her winding of the second web similarly connected other colliding secondary winding with the number of turns Nk Nk ₁ and _3, one secondary winding with the number of turns of the first rod Nk ₂ is connected in series with the secondary winding with the winding counter s Nk number of turns of the second rod _2, and the second - with the same counter her third winding terzhnya one secondary winding with the number of turns Nk ₂ of the second rod is connected in series with the secondary winding counter her winding the number of turns Nk ₂ of the first rod and the second - with the same counter her winding of the third rod, one secondary winding with the number of turns Nk ₂ of the third rod connected in series with the secondary winding of the winding counter s to Nk number of turns of the first bar _2, and the second - with the same winding counter to it second rod forming compound "zigzag", which leads, as well as secondary windings Num th turns Nk ₀ form a sequence multiphase transformer outputs, characterized in that the magnetic circuit of the transformer is flat chetyrehsterzhnevym, wherein the sectional area of outer rods half square rods arranged between them, and all winding covering one extreme rod are connected in series and in accordance with the same windings covering the other extreme shaft.

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