KR20180044616A - Variable inductor apparatus used for power conversion - Google Patents

Abstract

The present invention relates to a variable inductor apparatus for power conversion. According to the present invention, the variable inductor apparatus for power conversion includes: a magnetic core; an inductor coil disposed in a power converter while being wound around the magnetic core, and moveable in a lengthwise direction of the magnetic core with reference to a location of the magnetic core; a controller for detecting a predetermined electrical parameter from the inductor coil or the power converter, and generating displacement information required for following an inputted target parameter by using an error between the detected parameter and the inputted target parameter; and an actuator for changing a location of the inductor coil based on the displacement information fed back from the controller. According to the present invention, during variable control of inductance, the location of the coil instead of the magnetic core is moved to minimize power consumption of the actuator and to optimize system performance, and a control value for following a desired parameter is fed back from the controller to the actuator to automatically control a movement location of the coil and the inductance that varies according to the movement location.

Description

[0001] The present invention relates to a variable inductor apparatus for power conversion,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable inductor device for power conversion, and more particularly, to a variable inductor device for power conversion capable of variable control of inductance.

Generally, an inductor means a coil that induces a voltage proportional to a change in current. The inductance shows a property of interrupting the current flow due to the change of the magnetic field generated inside or around the coil.

Inductors used in power conversion circuits, such as DC-DC converters and DC-AC inverters, have functions mainly for current smoothing, current suppression, energy storage, and elimination of high frequency components of voltage and current due to semiconductor switching elements. Most inductors used in power conversion circuits have fixed inductance values. As a result, it can not cope with newly required inductance value due to the surrounding environment or circuit change.

As an alternative to this, a variable inductor can be used. The variable inductor has a structure mainly including a coil and a core. Conventional variable inductors change the position of the core or generate additional magnetic force in the core to vary the inductance value using magnetic saturation of the coil.

However, in the method of moving the core, there is a disadvantage that the power consumption of the driving actuator required for movement of the core is large because the weight of the core is heavy, and in the case of using the additional magnetic force, energy loss due to magnetic saturation is caused have.

The technology to be a background of the present invention is disclosed in U.S. Patent No. 5,999,077 (issued on December 12, 1999).

It is an object of the present invention to provide a variable inductor device for power conversion capable of minimizing power consumption and optimizing the performance of a system by varying the position of the inductor coil with respect to the magnetic core.

The present invention relates to an inductor coil which is disposed in a power converter in the form of being wound around the magnetic core and movable along the longitudinal direction of the magnetic core with respect to the position of the magnetic core so as to be variable in inductance, A controller for detecting a predetermined electrical parameter from the inductor coil or the power converter and generating displacement information required for following the target parameter by using an error between the detected parameter and the input target parameter, And an actuator for varying a position of the inductor coil based on the displacement information received by the variable inductor.

Here, the electrical parameter may include at least one of voltage, current, and phase detected from the inductor coil or the power converter.

Further, the magnetic core may be realized as a bar shape having a linear longitudinal direction. Here, the inductor coil may be wound on the whole or a part of the longitudinal direction of the magnetic core.

Also, the magnetic core may be embodied in a circle arc shape having a curved longitudinal direction and a gap between both ends. Here, the inductor coil may be partially wound around the longitudinal direction of the magnetic core.

In addition, the inductor coil may be separated from the air medium outside the one end of the magnetic core at one end thereof during the movement, and the inductance may vary according to the degree of the detachment.

The magnetic core may include a first core and a second core forming a longitudinal direction of a circular, polygonal or rectilinear shape as the ends or one end of the magnetic core come into contact with each other, May be formed of different materials. Here, the inductor coil may be partially wound around the longitudinal direction of the magnetic core.

The inductor coil may be configured such that one end of the inductor coil can be released from the first core toward the second core or from the second core toward the first core during the movement, .

According to the variable inductor apparatus for power conversion according to the present invention, when the position of the coil is moved instead of the magnetic core during the variable control of the inductance, the power consumption of the actuator can be minimized and the performance of the system can be optimized. There is an advantage that the moving position of the coil and the variable inductance can be automatically controlled according to feedback of the control value for the controller to the actuator.

1 is a view showing a variable inductor device for power conversion according to an embodiment of the present invention.
FIG. 2 is a view showing an inductor coil moving with reference to a magnetic core in FIG. 1. FIG.
FIG. 3 is a view showing another form of the inductor coil shown in FIG. 1. FIG.
4 and 5 are views showing another embodiment of a magnetic core applicable to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

The present invention relates to a variable inductor device for power conversion, and in a variable inductor implemented in a power converter, the inductance is controlled by changing the position of a winding instead of the position of the core, thereby minimizing the driving power of the actuator And a method of automatically controlling the winding position by using a negative feedback controller and ultimately varying the inductance easily is proposed.

1 is a view showing a variable inductor device for power conversion according to an embodiment of the present invention. Referring to FIG. 1, a variable inductor device 100 includes a magnetic core 110, an inductor coil 120, a controller 130, and an actuator 140.

The magnetic core 110 has an inductor coil 120 wound therearound. The magnetic core 110 can be made of various known materials used in an inductor element.

The inductor coil 120 is disposed on the outer surface of the magnetic core 110 and is wound in a spring shape from one end to the other end to be continuously wound. Lead terminals may be formed on both ends of the inductor coil 120. [ It is apparent that the inductor coil 120 can be implemented in a more compact form than that shown in Fig.

The magnetic core 110 and the inductor coil 120 form one inductor element and are used as an inductor element included in the power converter 10. [ The power converter 10 typically requires an inductor element for various purposes, and in this embodiment, the inductor element is implemented as a variable inductor. The inductor coil 120 is movable in parallel along the longitudinal direction of the magnetic core 110 with respect to the position of the magnetic core 110. The inductance of the inductor coil 120 is variable.

Here, in order to facilitate the movement of the inductor coil 120 and reduce the friction with the magnetic core 110, the inner side of the inductor coil 120 and the outer side of the magnetic core 110 are spaced apart from each other by a predetermined distance . Of course, auxiliary means (gap maintaining means) for maintaining the clearance gap between them may be further provided.

FIG. 2 is a view showing an inductor coil moving with reference to a magnetic core in FIG. 1. FIG. 2, when the inductor coil 120 moves upward (or downward) with respect to the magnetic core 110, a part of the upper end (or the lower end) of the inductor coil 120 moves toward the outer side of the magnetic core 110 The inside of the part is filled with the air medium instead of the core.

When the position of the inductor coil 120 is varied with respect to the magnetic core 110 as shown in FIG. 2, the magnetic flux density of the inductor coil 120 is changed in the vertical direction of the inductor coil 120, The ratio of the two materials having different magnetic permeability is changed, and the inductance value is changed accordingly.

The controller 130 detects a predetermined electrical parameter from the inductor coil 120 or the power converter 10. The controller 130 may directly or indirectly connect to the power converter 10 or the inductor coil 120 to detect various electrical parameters. The electrical parameters detected in the power converter 10 or the inductor coil 120 It may correspond to an element associated with the inductance value. The embodiment of the present invention may include at least one of voltage, current, and phase observed in the power converter 10 or at a predetermined portion of the inductor coil 120. [ In the case of the power converter 10, an electric parameter can be observed by setting a predetermined region of interest in the internal circuit. Of course, the inductor coil 120 also corresponds to some circuit elements of the power converter 10, and the electrical parameters may be used at any point in the power converter 10.

The controller 130 compares the currently detected parameter with the target parameter inputted from the outside, calculates an error, and generates displacement information required for following the target parameter by using the calculated error. Here, the target marameter may include at least one of voltage, current, and phase required to obtain a predetermined inductance.

The controller 130 sets the target parameter as a reference value, and causes the currently measured electric parameter to follow the reference. The controller 130 calculates the real time error of each other and generates displacement information for canceling the error. Here, of course, the displacement information includes distance and direction information on which the inductor coil 120 should move.

The actuator 140 varies the position of the inductor coil 120 based on the displacement information fed back from the controller 130. Here, the controller 130 continuously measures the error value even after the position of the inductor coil 120 is varied, and can continuously provide the feedback information to the actuator 140 until the error falls below the set value. The controller 130 and the actuator 140 may be implemented outside the power converter 10 or may be integrated into the system to form a single system.

As described above, the embodiment of the present invention can ultimately control the inductance by controlling the position of the actuator 140 with a feedback controller (negative feedback controller). In addition, since the position of the coil 120 is changed instead of the core 100, the driving power of the actuator 140 can be minimized as compared with a case where the core 110 having a heavy weight is moved.

In an embodiment of the present invention, the actuator 140 may be fixedly or adhesively connected to the inductor coil 120. Further, the actuator 140 may be driven by a voltage source or a current source, and may be either a magnetic force type or a piezoelectric type.

FIG. 3 is a view showing another form of the inductor coil shown in FIG. 1. FIG. 1, the inductor coil 120 is wound around the entire longitudinal direction of the magnetic core 110. In this case, 3, the inductor coil 220 may be wound around a portion of the magnetic core 210. In this case, In the case of FIG. 3 wound around a portion of the magnetic core 210, the inductance may change when the position of the inductor coil 220 varies within the length of the magnetic core 210, The inductance can be changed even when it is out of the core 210.

In the case of FIG. 1, the magnetic core 100 is implemented as a bar having a linear longitudinal direction, but the present invention is not necessarily limited to this.

4 and 5 are views showing another embodiment of a magnetic core applicable to an embodiment of the present invention. In the case of FIG. 4, the magnetic core is implemented as an arc, and FIG. 5 is implemented as an annular shape.

First, the magnetic core 310 shown in FIG. 4 is embodied as a circle arc having a gap between both ends. Unlike the previous FIG. 1, the magnetic core 310 has a curved longitudinal direction I have. The inductor coil 320 is wound around a portion of the magnetic core 310 in the longitudinal direction.

Accordingly, in FIG. 1, if the inductor coil 120 moves in one dimension, the inductor coil 320 in FIG. 4 can move two-dimensionally along the shape of the core. Of course, in the case of the present invention, the shape of the magnetic core can be realized in a form capable of three-dimensionally moving the inductor coil.

4, the inductance is changed while the inductor coil 320 moves, and the inductance can be varied even when a part of the inductor coil 320 is separated from the gap of the magnetic core 310. [

As described above, in each of the examples shown in Figs. 1 to 4, each of the inductor coils has a structure in which, at the time of movement, one end thereof can be released toward the air medium outside one end of the magnetic core, The inductance can be varied.

Next, the magnetic core 410 shown in FIG. 5 has a structure including a first core 411 and a second core 412 having an arc shape. The first core 411 and the second core 412 form a circular longitudinal direction when both end portions are in contact with each other. Also, the first and second cores 411 and 412 are formed of materials having different magnetic permeabilities. The inductor coil 420 is wound around a part of the length of the magnetic core 410.

In the case of FIG. 5, the same effect as described above can be obtained by implementing two zones with respect to the longitudinal direction of the core 410 in a material having a different magnetic permeability. Here, the ratios of the two zones may be the same or different.

In this structure, the inductor coil 420 can be separated from the first core 411 toward the second core 412 at one end thereof during movement, and the inductance can be varied according to the degree of separation.

Of course, the magnetic core 410 shown in FIG. 5 may be implemented in a polygonal shape instead of a circular shape. The polygonal structure also has a structure in which both ends of the first and second cores are in contact with each other, and each of the first and second cores may be formed at least once in angular shape instead of circular arc shape.

In addition, the magnetic core can be linearly formed. In this case, when one ends of the rod-shaped first and second cores are connected to each other to be in contact with each other, they are linearly formed as a whole. In this case, the first and second cores are also made of materials having different magnetic permeabilities from each other.

As described above, in the embodiment of the present invention, the core may be implemented as a one-dimensional linear core, or a shape capable of two-dimensional or three-dimensional movement of the coil may be used if necessary. Also, the actuator may be a linear or circular actuator depending on the shape of the core. The embodiment of the present invention is also applicable to a plurality of coils. According to the embodiment of the present invention, the inductance of the inductor in the power conversion device is changed and controlled to the optimum inductance according to the operating point, thereby minimizing the size, cost and power conversion loss of the device.

As a result, according to the variable inductor device for power conversion according to the present invention, when the position of the coil is shifted instead of the magnetic core during the variable control of the inductance, the power consumption of the actuator can be minimized and the performance of the system can be optimized. There is an advantage that the moving position of the coil and the variable inductance can be automatically controlled by feedback of the control value for following the controller to the actuator.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: Variable inductor device 110, 210, 310, 410:
120, 220, 320, 420: inductor coil 130:
140: Actuator

Claims (10)

core;
An inductor coil disposed in a power converter in the form of being wound around the magnetic core and movable along the longitudinal direction of the magnetic core with respect to the position of the magnetic core so that the inductance can be varied;
A controller for detecting a predetermined electrical parameter from the inductor coil or the power converter and generating displacement information required for following the target parameter by using an error between the detected parameter and the input target parameter; And
And an actuator for varying a position of the inductor coil based on the displacement information fed back from the controller. The method according to claim 1,
Wherein the electrical parameter comprises:
And at least one of voltage, current, and phase detected from the inductor coil or the power converter. The method according to claim 1,
The magnetic core includes:
A variable inductor device for power conversion implemented as a bar shape having a straight longitudinal direction. The method of claim 3,
The inductor coil includes:
Wherein the magnetic core is wound around the magnetic core in whole or in part with respect to the longitudinal direction of the magnetic core. The method according to claim 1,
The magnetic core includes:
A variable inductor device for a power conversion, the device being implemented in a circle arc shape having a curved longitudinal direction and having a gap between both ends. The method of claim 5,
The inductor coil includes:
Wherein the magnetic inductor is wound around a part of the magnetic core in the longitudinal direction thereof. The method according to claim 3 or 5,
The inductor coil includes:
Wherein one end of the movable core is detachable toward the air medium outside the one end of the magnetic core at the time of movement, and the inductance is varied according to the degree of detachment. The method according to claim 1,
The magnetic core includes:
A first core and a second core that form a circular, polygonal, or straight lengthwise direction as the ends or one end thereof contact each other,
Wherein the first core and the second core are formed of materials having different magnetic permeabilities from each other. The method of claim 8,
The inductor coil includes:
Wherein the magnetic inductor is wound around a part of the magnetic core in the longitudinal direction thereof. The method of claim 8,
The inductor coil includes:
Wherein one end of the movable core is movable from the first core toward the second core or from the second core toward the first core during the movement, and the inductance varies according to the degree of the deviation.

Images