Self-coupling controllable reactor

Abstract

A self-coupling controllable reactor is characterized in that the self-coupling controllable reactor comprises a working winding (1), a control winding (2) is a part of the working winding (1), and the control winding is divided into m sections with the same number of turns through taps K1 / K2-Km + 1. The m groups of power components (3) are respectively bridged between K1 and K2, between K2 and K3, and between-Km and Km + 1, and each group of power components is connected in series with the fast-acting fuse (4).

Description

Technical Field

[0001] The present invention provides a controllable reactor, in particular a self-coupling controllable reactor. Background Art

[0002] Controllable reactors are widely used in dynamic reactive power compensation, arc suppression coils, motor soft start and other technical fields. At present, the controllable reactors are basically controlled by DC to control AC. That is, by adjusting the size of the DC current of the control winding, the impedance value of the working winding is adjusted. The advantage of this technical route is that the terminal voltage of the power component is low and the control current is also small, but the disadvantages are also obvious, mainly in the following aspects: 1. The control efficiency is not high and the control range is not large; 2. Magnetic saturation is accompanied by large harmonic pollution; 3. Over-range control is easy to form a control dead zone and burn the power component; 4. A special design of the DC flux circuit is required, the iron core volume is large, and the silicon steel sheet loss is large; 5. The AC and DC currents are independent of each other, the heat generation is large, and the wire consumption is large. If the AC control technical route is adopted, that is, by adjusting the size of the AC current of the control winding to adjust the working winding impedance, either the voltage at both ends of the power component is very high or the control current is very large, which is difficult to achieve in the medium and high voltage field. Therefore, reducing the terminal voltage of the power component and reducing the control current at the same time are technical problems that need to be solved by the AC control technical route of the controllable reactor. Summary of the invention

[0003] In order to solve the technical problem that the voltage applied to the two ends of the power component of the AC control controllable reactor is high, the power component is easily broken down or the control current is too large, the present invention provides a new type of controllable reactor, the control winding of the controllable reactor is a part of the working winding, and the control winding is divided into a plurality of winding sections with equal turns, each section of the winding is connected across a group of power components, because the induced voltage is evenly distributed in each section of the winding, the voltage at both ends of the power component will be greatly reduced, and because the turns of multiple control windings are superimposed, the control current can also be effectively reduced. At the same time, the iron core of the controllable reactor adopts a three-phase three-column structure, which has the advantages of small size, compact structure, no leakage magnetic field and low cost.

[0004] The technical solution adopted by the present invention to solve its technical problem is: a self-coupling controllable inductor, including a three-phase three-column iron core and a power component. The three-phase three-column iron core is wound with a three-phase working winding on the core column, and a part of the high-voltage winding is extracted as a control winding.

[0005] Furthermore, the control winding is divided into several sections with equal number of turns by means of an intermediate tap, each section is connected across a power component, and the current flowing through the control winding is adjusted by the power component, thereby achieving the purpose of controlling the reactance of the working winding. Since each section of the control winding has fewer turns, the induced voltage is lower, and the voltage applied to both ends of the power winding is lower. At the same time, since the total number of turns of the control winding is large, the control current is not very large.

[0006] Furthermore, the power component may be an anti-parallel thyristor component or an ITBG component according to control requirements.

[0007] Furthermore, a fast fuse is connected in series at the front end of the power winding, which quickly blows when the power component of this section breaks down, and the power component of this section exits control without affecting the normal operation of the controllable reactor, and can be replaced during the next maintenance.

[0008] Furthermore, the three-phase three-column iron core is formed by stacking silicon steel sheets.

[0009] The beneficial effects and features of the present invention are: The control winding is part of the working winding, the control current and the working current partially offset each other, and the heat generated is small.

[0010] The control winding disconnection design reduces the operating voltage of the power components while ensuring appropriate control current.

[0011] Both the working current and the control current are AC currents, the three-phase magnetic flux vector sum is zero, there is no magnetic leakage, the magnetic fluxes generated are in opposite directions and cancel each other out, and the control efficiency is high.

[0012] The iron core has a three-phase three-column structure, and the volume of the controllable reactor is reduced by 50%. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention is further described below in conjunction with the accompanying drawings.

[0014] Figure 1 It is a wiring schematic diagram of a preferred embodiment of the present invention.

[0015] Figure 2 It is a control principle diagram of a preferred implementation of the present invention.

[0016] Figure 3 It is a core winding diagram for a preferred embodiment of the present invention.

[0017] The numbers in the figure represent: 1-working winding, 2-control winding, 3-power component, 4-fast fuse, 5-three-column iron core.

[0018] AA phase working winding head, BB phase working winding head, C-C phase working winding head, XA phase working winding tail, YB phase working winding tail, ZC phase working winding tail, K1--Km+1-control winding tap. DETAILED DESCRIPTION

[0019] Please refer to Figure 1 A self-coupling controllable reactor comprises a working winding (1), a control winding (2) being a part of the working winding (1), the control winding being divided into m sections with equal number of turns by tapping K1 / K2--Km+1, m groups of power components (3) being respectively connected between K1 and K2, K2 and K3, ---Km and Km+1, each group of power components being connected in series with a fast fuse (4), which is quickly fused when the power component breaks down, and the group of power components is disconnected and exits control, so that the induced voltage of the two sections of the winding is not superimposed to increase the voltage of the adjacent power components and cause a chain reaction of breakdown, thereby ensuring that the controllable reactor can still work normally in the event of a local fault, the number of turns of the working winding (1) is N, the number of turns of the control winding (2) is n, and the number of turns of each small section of the control winding is n / m.

[0020] The power component (3) may be an anti-parallel thyristor component or an IGBT device, depending on the control target of the controllable reactor.

[0021] Please refer to Figure 2 A self-coupling controllable reactor, wherein a power supply voltage Un is applied to both ends of a working winding (1), and a control voltage Uk=(Un*n) / (N*m) is applied to both ends of a power component (3). Under a certain power supply voltage, after the winding transformation ratio of the self-coupling controllable reactor is determined, the control voltage Uk applied to both ends of the power component (3) can be changed by changing the number of segments m of the control winding (2). The larger the m, the lower the Uk. The purpose of segmenting the control winding (2) is to reduce Uk to a level below the safe voltage that the power component (3) can withstand. That is, the number of segments m of the control winding (2) is determined by the power supply voltage Un, the winding transformation ratio, and the withstand voltage of the power component. As long as Uk is below the safe voltage that the power component can withstand through calculation, m=1 can also become the preferred solution of the self-coupling controllable reactor. The magnitude of the control current Ik is adjusted by the power winding, thereby adjusting the magnitude of the working current In. The control current Ik=In(N / n) is independent of m and is a normal transformation ratio of the control winding (2) and the working winding (1), which is not very large.

[0022] Please refer to Figure 3A self-coupling controllable reactor, the core is a three-phase three-column core (5), the three-phase three-column core (5) is made of laminated silicon steel sheets, working windings (1) are wound on the three-phase core columns, the head of the three-phase working winding (1) is A / B / C, and the tail is X / Y / Z respectively, taps K1, K2-----Km+1 are respectively drawn out from the middle of the working winding (1) as a control winding (2), the control winding (2) is divided into m segments with equal number of turns by the taps, m is a natural number greater than or equal to 1, and m=1 is also one of the preferred solutions of this self-coupling controllable reactor, K1 is the head of the control winding (2), K1 can overlap with A / B / C, and can also have a certain number of turns interval with A / B / C, Km+1 is the tail of the control winding (2), similarly, Km+1 can overlap with X / Y / Z, and can also have a certain number of turns interval with X / Y / Z.

[0023] During operation, the magnitude of the control current Ik of the control winding (2) is adjusted by adjusting the m groups of power components (3) simultaneously, thereby achieving impedance adjustment of the working winding (1).

[0024] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and the description in the specification are only to illustrate the structural relationship and principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention has various changes and improvements, and these changes and improvements all fall within the scope of the protection claimed by the present invention.

[0025] The scope of protection sought for the present invention is defined by the following claims and their equivalents.

Claims

1. A self-coupling controllable reactor, characterized in that: A self-coupling controllable reactor comprises a working winding (1), a control winding (2) which is a part of the working winding (1), and the control winding is divided into m sections with equal number of turns through a tap K1 / K2--Km+1. M groups of power components (3) are respectively connected between K1 and K2, K2 and K3, ---Km and Km+1, and each group of power components is connected in series with a fast fuse (4).

2. The autocoupler controllable reactor according to claim 1, characterized in that: The power component (3) may be a reverse-parallel thyristor component or an IGBT device, depending on the control target of the controllable reactor.

3. The autocoupler reactor according to claim 1, characterized in that: The number of sections m of the control winding (2) is determined by the power supply voltage Un, the winding ratio, and the withstand voltage of the power component. As long as Uk is calculated to be below the safe voltage that the power component can withstand, m=1 can also become the preferred solution for this autocoupled controllable reactor.

4. The autocoupler controllable reactor according to claim 1, characterized in that: K1 is the head of the control winding (2). K1 can overlap with A / B / C or have a certain number of turns interval with A / B / C. Km+1 is the tail of the control winding (2). Similarly, Km+1 can overlap with X / Y / Z or have a certain number of turns interval with X / Y / Z.

5. The auto-coupling controllable reactor according to claim 1, characterized in that: The iron core is a three-phase three-column iron core (5), and the three-phase three-column iron core (5) is made of laminated silicon steel sheets.

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