A kind of orthogonal controllable reactor

Abstract

A novel orthogonal controllable reactor comprises: a DC core and an AC core; wherein the novel orthogonal controllable reactor adopts a structure in which the AC and DC cores are completely orthogonal, wherein the AC core is a closed core and the DC core adopts two identical C-shaped cores; the DC core is in the middle of the AC core and is orthogonal to the AC core to form a "cross" shaped orthogonal controllable reactor. The present invention further improves the adjustable range of the inductance value of the controllable reactor while reducing the harmonic content, and optimizes it by adding air gaps and the number of DC cores, and has better performance than the prior art.

Description

Technical Field

[0001] The present invention relates to the field of electric power equipment, and in particular to an orthogonal controllable reactor. Background Art

[0002] As a basic component of power equipment, reactors are widely used in power system stability control, power flow regulation, motor soft start and fault current suppression. When dealing with series line voltage fluctuations caused by load changes and new energy access, traditional fixed reactors cannot dynamically adjust their reactance values ​​to control the power flow. Similarly, for parallel filtering, since the reactance value is fixed, the filter it forms can only filter out fixed-frequency harmonics, and cannot filter out harmonics with changing frequencies.

[0003] The controllable reactors currently used in engineering mainly include traditional controllable reactors, thyristor-controlled controllable reactors, magnetically controlled reactors, pulse width modulation controllable reactors, and superconducting controllable reactors. Traditional controllable reactors are mechanically controlled reactors, which mainly adjust the number of coil turns in the connected circuit by adjusting the taps or by adjusting the width of the air gap between the iron cores to make the inductance value controllable. Due to the mechanical structure, the inductance value of traditional controllable reactors will change discretely, which cannot meet the needs of continuous regulation and has long operation time and short service life. Thyristor-controlled reactors control the size of the conduction angle to control the size of the current, which is equivalent to the change of the inductance value. This type of reactor is composed of a cascade of multiple thyristors, which is expensive and easy to generate harmonics, affecting the quality of electric energy. Magnetically controlled reactors control the size of the magnetic flux in the iron core to change the magnetic permeability to achieve controllable inductance value. The magnetic-assisted controllable reactor will generate a large amount of harmonics and noise in the working winding due to the saturation of the iron core in the working area. Pulse width modulation controllable reactors achieve inductance value control through bidirectional switch control, which is relatively complex to control and has a high cost. Superconducting controllable reactors use the characteristics of superconducting materials to control the inductance value, but the conditions for its operation under superconducting conditions are too harsh and have not yet been widely used. Summary of the invention

[0004] In view of the above problems, the present invention is proposed to provide an orthogonal controllable reactor that overcomes the above problems or at least partially solves the above problems.

[0005] In order to solve the above technical problems, the embodiments of the present application disclose the following technical solutions:

[0006] An orthogonal controllable reactor comprises: a DC core and an AC core; wherein the orthogonal controllable reactor adopts a structure in which the AC and DC cores are completely orthogonal, wherein the AC core is a closed core and the DC core adopts two identical C-shaped cores; the DC core is in the middle of the AC core and is orthogonal to the AC core to form a "cross" shaped orthogonal controllable reactor.

[0007] Furthermore, it also includes: an AC winding; wherein: the AC winding includes two, a first AC winding and a second AC winding are respectively wound on two side columns of the AC iron core, serving as working windings of the reactor.

[0008] Furthermore, it also includes: a DC winding; wherein: the DC winding includes two, a first DC winding and a second DC winding are respectively wound on two side columns of the DC core, serving as control windings of the reactor.

[0009] Furthermore, a gas dielectric air gap will be set in the middle of the AC iron core. By setting the gas dielectric air gap, an air gap is added in the closed magnetic circuit formed by the AC working iron core to optimize the magnetization curve of the AC iron core, making the inductance adjustment characteristics of the orthogonal inductor more linearly adjustable, suppressing the harmonic content, and reducing the impact of harmonics on the power quality of the main circuit.

[0010] Furthermore, the orthogonal controllable reactor can adopt a structure with one AC core and three DC cores that are completely orthogonal, and air gaps are provided on both sides of the AC core; this structure can be used to control the inductance value in the AC circuit by controlling the size of the DC input and the number of circuits.

[0011] Furthermore, the orthogonal controllable reactor adopts a DC core and three AC cores in a completely orthogonal structure, and air gaps are provided on both sides of the AC cores; the three AC cores are connected to the three-phase system with A, B, and C phases respectively.

[0012] Furthermore, the inductance value of the orthogonal controllable reactor can be adjusted by changing the number of DC cores, modifying the position of the air gap, and replacing the air medium.

[0013] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0014] The present invention discloses an orthogonal controllable reactor, comprising: a DC core and an AC core; wherein the orthogonal controllable reactor adopts a structure in which the AC and DC cores are completely orthogonal, wherein the AC core is a closed core, and the DC core adopts two identical C-shaped cores; the DC core is in the middle of the AC core and is orthogonal to the AC core to form a "cross"-shaped orthogonal controllable reactor. The present invention further improves the adjustable range of the inductance value of the controllable reactor while reducing the harmonic content, and optimizes it by adding air gaps and the number of DC cores, and has better performance than the prior art.

[0015] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 This is a schematic diagram of a cross-shaped structure of an orthogonal controllable reactor in Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic diagram of the magnetic field in the orthogonal region in Example 1 of the present invention;

[0019] Figure 3 This is a schematic diagram of an equivalent magnetic circuit in Embodiment 1 of the present invention;

[0020] Figure 4 This is a schematic diagram of the position of the air gap in the AC core in Embodiment 1 of the present invention;

[0021] Figure 5 Schematic diagram of equivalent magnetization curves with and without air gap in Example 1 of the present invention;

[0022] Figure 6 This is a schematic diagram of a F-shaped structure of an orthogonal controllable reactor in Embodiment 1 of the present invention;

[0023] Figure 7 This is a schematic diagram of the structure of an orthogonal controllable reactor applied to a three-phase system in Example 1 of the present invention. DETAILED DESCRIPTION

[0024] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0025] In order to solve the problems existing in the prior art, an embodiment of the present invention provides an orthogonal controllable reactor. Example 1

[0026] This embodiment discloses an orthogonal controllable reactor, including: a DC core and an AC core; wherein the orthogonal controllable reactor adopts a structure in which the AC and DC cores are completely orthogonal, wherein the AC core is a closed core, and the DC core adopts two identical C-shaped cores; the DC core is in the middle of the AC core and is orthogonal to the AC core to form a "cross" shaped orthogonal controllable reactor. The orthogonal controllable reactor also includes: an AC winding and a DC winding, wherein: the AC winding includes two, the first AC winding and the second AC winding are respectively wound on the two side columns of the AC core, as the working winding of the reactor. The DC winding includes two, the first DC winding and the second DC winding are respectively wound on the two side columns of the DC core, as the control winding of the reactor.

[0027] Specifically, Figure 1 The structure is mainly composed of an AC core and a DC core, wherein the AC core has two windings, Wac1 and Wac2, wound on the side poles, and the DC core has two windings, Wdc1 and Wdc2, wound on the side poles. The AC winding is the working winding, and the AC part is connected to the circuit as a whole to form the main body of the reactor. Figure 1 The structure of the orthogonal reactor shows that its equivalent magnetic circuit is as follows: Figure 3 As shown. In the figure, Rac and Rdc are the magnetic resistances of the non-orthogonal parts of the AC core and the DC core respectively, Ra1 and Ra2 are the magnetic resistances of the two orthogonal parts of the AC core, and Rd1 and Rd2 are the magnetic resistances of the two orthogonal parts of the DC core. Through the magnetic circuit, it can be seen that changing the magnetomotive force Fdc can make Ra1 and Ra2 controllable, thereby realizing the adjustment of the reactor. The specific implementation method is as follows:

[0028] According to the laws of electromagnetism and Figure 2 Content available

[0029] (1)

[0030] (2)

[0031] (3)

[0032] (4)

[0033] (5)

[0034] In the above formula, N a is the total number of turns of the AC winding coil; i a is the current flowing in the AC winding; H a1 , H a2 They are the magnetic field intensity of the non-orthogonal part of the AC core and the magnetic field intensity of the orthogonal part of the AC core respectively;H d1 , H d2 They are the magnetic field intensity of the non-orthogonal part of the DC core and the magnetic field intensity of the orthogonal part of the DC core respectively; l a , l a1 , l a2 They are the total magnetic path length of the AC core, the magnetic path length of the non-orthogonal part and the magnetic path length of a single orthogonal part; B a , B d They are the magnetic induction intensity of the non-orthogonal part of the AC core and the magnetic induction intensity of the non-orthogonal part of the DC core respectively.

[0035] The flux coefficient in equation 5 above is a 1 、a 3 、a 5 、a n It depends on the reactor body and the materials used. n Just take 3. Then we can get

[0036] (6)

[0037] among them Φ = B·S, And for a specific core, its magnetic path length l and cross-sectional area S is a fixed value, Formula 6 can be rearranged as

[0038] (7)

[0039] In the formula .

[0040] Substituting the above formula into 1, we can get

[0041] (8)

[0042] In the formula, Φ a , Φ d are the magnetic flux of the AC and DC cores respectively, S a 、S d are the cross-sectional areas of the AC and DC cores respectively. Li=NΦ Relationship and rearrange equation 8 to get

[0043] (9)

[0044] Assume that the magnetic permeability of the orthogonal part of the core is μ o , the magnetic permeability of the orthogonal part in the AC direction is μ a2 , the magnetic permeability of the orthogonal part in the DC direction is μ d2 , then according to formula 3, we can know

[0045] (10)

[0046] (11)

[0047] At the same time, from formula 7, we can know

[0048] (12)

[0049] Based on the above, the inductance value of this orthogonal reactor can be expressed as

[0050] (13)

[0051] In the formula μ a1 is the magnetic permeability of the non-orthogonal part of the AC core.

[0052] According to the above content, the specific implementation method of adjusting the inductance value of the orthogonal controllable reactor is:

[0053] (1) When B d =0, that is, when the control current applied to the DC circuit is 0, μ o Reaching the maximum value, μ o = μ a1 ,inductance L There is a maximum value.

[0054] (2) When the control current added to the DC circuit reaches the maximum value designed for the orthogonal reactor, μ o To reach the minimum value, the inductance L Has a minimum value.

[0055] (3) Increase l a2 Can be further reduced L min The value of increases the inductance adjustment range. The inductance control range is expressed as Where L min expressL Minimum value, L max express L Maximum value.

[0056] The above content is the first part of this embodiment. Based on the first part, this embodiment proposes to optimize the performance of this type of orthogonal reactor, and the specific implementation content is as follows:

[0057] Oriented silicon steel sheets themselves have the characteristics of high magnetic permeability when unsaturated, low magnetic permeability when saturated, and obvious knee point of magnetic permeability curve. Conventional magnetic-assistance reactors all have the problem of easy saturation of the iron core. The present invention optimizes its structure to solve this problem. In this embodiment, a gas dielectric air gap is also set in the middle of the AC iron core. By setting the gas dielectric air gap, an air gap is added to the closed magnetic circuit formed by the AC working iron core to optimize the magnetization curve of the AC iron core, so that the inductance adjustment characteristics of the orthogonal reactor are more linearly adjustable, the harmonic content is suppressed, and the influence of harmonics on the power quality of the main circuit is reduced.

[0058] Specifically, Figure 4 As shown. Figure 4 Overall length shown L , air gap length l g The cross-sectional area of ​​the core is S, and the total magnetic resistance of the magnetic circuit is:

[0059] (14)

[0060] In the formula R m is the total magnetic resistance of the circuit, μ is the equivalent total magnetic permeability, μ Fe is the magnetic permeability of the core, μ air is the magnetic permeability of the air gap. Since, μ Fe Much greater than μ air , so the overall equivalent magnetic permeability of the core is:

[0061] (15)

[0062] The equivalent magnetization curves before and after adding the air gap are as follows: Figure 5 As shown, the linear characteristics of the orthogonal controllable reactor are improved as a whole, and the generation of harmonics is suppressed.

[0063] The above content is the second part of this real-time example. Based on the first and second parts, this embodiment improves the above structure. Specifically: the orthogonal controllable reactor can adopt a structure with one AC iron core and three DC iron cores that are completely orthogonal, and at the same time, air gaps are provided on both sides of the AC iron core; by adopting this structure, the inductance value in the AC circuit is regulated by controlling the magnitude and number of DC inputs. The orthogonal controllable reactor adopts a structure with one DC iron core and three AC iron cores that are completely orthogonal, and at the same time, air gaps are provided on both sides of the AC iron core; the three AC iron cores are connected to the three-phase system respectively with A, B, and C phases.

[0064] Specifically, this embodiment proposes a "rich" - shaped expansion structure for this type of orthogonal reactor. The specific implementation content is as follows:

[0065] As can be seen from the first two parts of the present invention, increasing the orthogonal region can further lower the lower limit of the minimum inductance value of the orthogonal controllable reactor, thereby further increasing its inductance value adjustment range. At the same time, adding air gaps in the working iron core can reduce the harmonic content. Based on this, the present invention proposes a Figure 6 "rich" - shaped orthogonal controllable reactor structure as shown. Under the same conditions, this structure can have a larger additional control current, better linearity in control characteristics, and a wider adjustable range of inductance values.

[0066] Based on this structure, the functions of the AC iron core and the DC iron core can be interchangeably used. That is, the three columns are respectively connected to the A, B, and C phases of the three-phase system as the working circuit, as Figure 7 shown, and the DC is used as the overall control circuit for the three phases to regulate the inductance value connected to the three-phase system.

[0067] An orthogonal controllable reactor disclosed in this embodiment includes: a DC iron core and an AC iron core; among them, the orthogonal controllable reactor adopts a structure where the AC and DC iron cores are completely orthogonal. The AC iron core is a closed iron core, and the DC iron core adopts two identical C-shaped iron cores; the DC iron core is orthogonal to the middle of the AC iron core to form a "cross" - shaped orthogonal controllable reactor. The present invention further improves the adjustable range of the inductance value of the controllable reactor while reducing the harmonic content, and is optimized by adding air gaps and the number of DC iron cores. Compared with the prior art, its performance is more superior.

[0068] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the protection scope of the present disclosure. The appended method claims present the elements of various steps in an exemplary order and are not limited to the specific order or hierarchy described.

[0069] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0070] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0071] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0072] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0073] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. An orthogonal controllable reactor, characterized in that: include: DC core and AC core; wherein, the orthogonal controllable reactor adopts a structure in which the AC and DC cores are completely orthogonal, wherein the AC core is a closed core and the DC core adopts two identical C-shaped cores; the DC core is orthogonal to the AC core in the middle to form a "cross" shaped orthogonal controllable reactor; the orthogonal controllable reactor adopts a structure in which one AC core and three DC cores are completely orthogonal, and air gaps are provided on both sides of the AC core; this structure is used to control the inductance value in the AC circuit by controlling the size of the DC input and the number of loops; the orthogonal controllable reactor adopts a structure in which one DC core and three AC cores are completely orthogonal, and air gaps are provided on both sides of the AC core. Air gaps are provided on both sides of the AC core; the three AC cores are connected to the three-phase system with A, B and C phases respectively; an air gap is added in the closed magnetic circuit formed by the AC working core by setting the gas medium air gap to optimize the magnetization curve of the AC core, so that the inductance adjustment characteristics of the orthogonal reactor are more linearly adjustable, the harmonic content is suppressed, and the influence of harmonics on the power quality of the main circuit is reduced; the AC winding includes 2, the first AC winding and the second AC winding are respectively wound on the two side columns of the AC core, as the working windings of the reactor; the DC winding includes 6, which are respectively wound on the two side columns of the DC core, as the control windings of the reactor.

2. An orthogonal controllable reactor as claimed in claim 1, characterized in that: By changing the number of DC cores, changing the position of the air gap, and replacing the air medium, the purpose of adjusting the inductance value of the orthogonal controllable reactor can be achieved.

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