KR20170099037A - Power supply apparatus using current transformer - Google Patents

Abstract

Provided is a power supply apparatus using a current transformer. According to an embodiment of the present invention, the power supply apparatus using a current transformer comprises: a current transformer installed on a power line as a clamp type to induce power, and having a plurality of unit coils; a switch unit connected to each of the unit coils for switching; and a sensing module for detecting a voltage induced from any one of the unit coils, and controlling the switch unit such that at least a part of the unit coils is connected in series or in parallel according to the detected voltage in order to produce constant power. According to the present invention, since a power induction ratio is adjusted according to a change of a current of the power line according to time, it is possible to provide constant power. Also, since complexity or capacity of a power generation unit circuit and a power storage unit of a rear end is reduced, it is possible to easily implement an optimum system and reduce manufacturing costs. In addition, since power loss for high current time and the capacity of the power storage unit for power storage with respect to low power time are minimized, it is possible to improve power supply efficiency.

Description

Technical Field [0001] The present invention relates to a power supply apparatus using a current transformer,

The present invention relates to a power supply apparatus, and more particularly, to a power supply apparatus using a current transformer capable of providing a constant output even when a current state of a power line is changed.

Recently, with the spread of Internet (IoT), various types of IoT devices are emerging. These IoT devices form a specific purpose sensor network, such as a smart grid. Particularly, in order to configure a network for all environments, the IoT device is often installed on an outer surface of a high-rise building or a basement manhole where people are not easily accessible.

In this environment, installing a separate power distribution board or outlet for powering the IoT device is not only costly, but also considering the continuous expansion of the IoT device, .

However, the battery needs to be replaced periodically after the lifetime has elapsed, and the cost of maintenance increases, such as personnel input for increasing the number of IoT device batteries installed and work hours, . Therefore, there is a demand for a power supply scheme capable of minimizing maintenance for such IoT devices.

On the other hand, a technique of supplying power by inducing power using a current transformer (CT) detachably attachable on a power line is being developed. As described above, the power supply apparatus using a current transformer can easily induce electric power only by attaching a current transformer to a power line, and thus it is considered as an alternative to the IoT device.

However, in the case of deriving the power from the power line, since the current state of the power line may greatly vary with time, not only can a constant power be induced, but also the power loss increases when the current of the power line is large, The capacity of the power storage unit for supplying power is increased and it is becoming an obstacle to use as a power supply unit.

Therefore, there is an urgent need to develop a technique that can induce power easily from a power line by using a current transformer and generate power by inducing a constant power even when a current state of a power line changes.

KR 10-1040732 B (June 3, 2011 Enrollment)

It is an object of the present invention to provide a power supply apparatus using a current transformer that can provide a constant power by adjusting a power induction ratio according to a current state of a power line.

According to an aspect of the present invention, there is provided a transformer comprising: a transformer installed in a power line as a clamp type to induce power and having a plurality of unit coils; A switch unit connected to each of the plurality of unit coils and switching the unit coils; And a sensing unit for sensing a voltage derived from any one of the plurality of unit coils and controlling the switch unit so that at least a part of the plurality of unit coils is connected in series or in parallel according to the detected voltage, The present invention provides a power supply apparatus using a current transformer including a module.

According to a preferred embodiment of the present invention, the sensing module calculates an average value for a predetermined time with respect to a voltage induced from any one of the plurality of unit coils, and when the calculated average value is larger than the reference value, The switch unit can be controlled so that at least a part of the coil is connected in parallel.

The sensing module may control the switch unit such that at least a part of the plurality of unit coils is connected in series when the calculated average value is smaller than the reference value.

In addition, the sensing module may control the switch unit such that the plurality of unit coils are connected in series, parallel, or series-parallel combination according to the magnitude of the detected voltage.

The sensing module may determine the number of the plurality of unit coils connected in series or parallel according to the magnitude of the detected voltage.

The switching unit may have a plurality of input terminals and a pair of output terminals connected to the plurality of unit coils, and one of the unit coils may be connected to the input terminal to which one of the unit coils is connected, An input terminal connected to the pair of output terminals may be provided with a changeover switch on the other side of the one unit coil, the other side of the other unit coil, and the remaining unit coils.

Also, the power supply device using the current transformer may include a power generator connected to an output of the switch unit to generate power by the induced voltage; And a power storage unit for storing the generated power.

The power generation unit may include: a power conversion unit that converts the output of the switch unit into DC power; And a regulator for adjusting the converted DC power to be constantly output.

The power storage unit may include a supercapacitor or a battery.

According to another aspect of the present invention, there is provided a power supply apparatus for supplying electric power to an Internet (IoT) device installed in an area where access is not easy, comprising: a current transformer installed in a power line as a clamp type, A switch unit connected to each of the plurality of unit coils and switching the unit coils; And a sensing unit for sensing a voltage derived from any one of the plurality of unit coils and controlling the switch unit so that at least a part of the plurality of unit coils is connected in series or in parallel according to the detected voltage, module; A power generator connected to an output of the switch unit to generate power by the induced voltage; And a power storage unit for storing the generated power. Here, the power storage unit is connected to the object Internet device by wire.

According to another aspect of the present invention, there is provided a power supply apparatus comprising: a plurality of current transformers installed in a power line as a clamp type to induce power; A switch unit connected to and switching to each of the plurality of current converters; And a sensing module for detecting a voltage derived from one of the plurality of current converters and controlling the switch part so that at least a part of the plurality of current converters is connected in series or in parallel according to the detected voltage to generate a constant power The present invention provides a power supply apparatus using a current transformer.

According to the present invention, since a plurality of power induction units are provided and the connection of the power induction unit is switched in series or in parallel according to the current state of the power line, the power induction ratio is adjusted according to the current change of the power line over time, can do.

Further, since the complexity or capacity of the power generation unit circuit and the power storage unit at the rear end of the power induction unit is reduced by adjusting the ratio to induce a constant power even when the current of the power line changes, it is easy to implement the optimum system, .

In addition, the present invention minimizes power loss for a high current time by connecting the power induction units in parallel in a high current time and connecting the power induction units in series in a low current time, The capacity of the storage unit is minimized, and the power supply efficiency can be improved.

1 is a configuration diagram of a power supply apparatus using a current transformer according to an embodiment of the present invention;
2 is a diagram showing an example of a switch unit in a power supply apparatus using a current transformer according to an embodiment of the present invention;
Fig. 3 is a configuration diagram of the switch unit of Fig. 2,
Fig. 4 is a block diagram of the switch unit of Fig. 2,
Fig. 5 is a configuration diagram of the switch unit of Fig. 2,
6 is a configuration diagram of another example of a power supply apparatus using a current transformer according to an embodiment of the present invention;
FIG. 7 is a flowchart illustrating an operation of a power supply apparatus using a current transformer according to an embodiment of the present invention,
FIG. 8 is a flowchart illustrating a stepwise process of series-parallel switching of a power-inducing unit in a power supply apparatus using a current transformer according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

The power supply apparatus 100 using a current transformer according to an embodiment of the present invention includes a current transformer 110a, a switch unit 116 and a sensing module 120 as shown in FIG.

The power supply 100 using the current transformer is for supplying electric power to the IoT device 14, particularly to the IoT device 14 installed in an area where the access is not easy . At this time, the power supply apparatus 100 using the current transformer can supply electric power to the IoT device 14 by wire.

Here, the power line 12 is a power line that is exposed to the outside and can be accessed, such as a power line embedded in a ground or installed in a pole.

The current transformer 110a is detachably attached to the power line 12 and is configured as a clamp type. That is, the current transformer 110a divides the magnetic core 112 inside the current transformer 110 into two parts so as to facilitate attachment and detachment to the power line 12, and constitutes upper and lower magnetic coils, and a plurality of unit coils 114a, 114b are wound.

Here, the unit coils 114a and 114b may be wound at different positions on the magnetic core 112, or may be wound at the same position. At this time, the surfaces of the unit coils 114a and 114b are coated with an insulator.

The plurality of unit coils 114a and 114b are wound on the magnetic core 112 and one of the coils 114b is wound on the magnetic core 112 to detect the amount of current of the power line 12. [ And the remaining coil 114a is used for power for inducing power from the power line 12 to generate electric power.

That is, the current transformer 110a has the function of a plurality of current transformers substantially by winding the plurality of unit coils 114a and 114b on the magnetic core 112.

In FIG. 1, the plurality of unit coils 114a and 114b are shown as having two functions based on the function. However, the plurality of unit coils 114a, which are power generating coils, may be configured.

The switch unit 116 is connected to each of the plurality of unit coils 114a and 114b and switches according to the sensing module 120. [

The switch unit 116 is provided with a changeover switch at an input terminal connected to each of the plurality of unit coils 114a and 114b so that the plurality of unit coils 114a and 114b are connected in series, Each changeover switch can be switched. However, the switch unit 116 is not limited to this, and may be configured as a logic device.

For example, as shown in FIG. 2, the switch unit 116 includes input terminals C11 through Cn1, output terminals Co1 and Co2, and changeover switches S11 through Sn1.

The input terminals C11 to Cn1 are connected to the plurality of unit coils 114-1 to 114-n, respectively. That is, the input terminals C11 and C12 are connected to the unit coil 114-1, the input terminals C21 and C22 are connected to the unit coil 114-2, and the input terminals Cn1, Cn2 are connected to the unit coil 114-n. At this time, an input terminal to which one side of one unit coil is connected, that is, an input terminal C11 and an input terminal to which one side of the other unit coil is connected, that is, an input terminal Cn2, And may be connected to a pair of output terminals Co1 and Co2.

The pair of output terminals Co1 and Co2 are respectively connected to an input terminal (for example, C11) corresponding to one unit coil and an input terminal (for example, Cn2) corresponding to another unit coil And constitute final terminals of a plurality of unit coils 114-1 to 114-n connected in series or in parallel.

The changeover switch S11-Sn1 is connected to either one of the unit coils corresponding to the input terminals C11 and Cn2 connected to the output terminals Co1 and Co2 or the input terminals C12 and C12 connected to the other unit coil, Cn1) and input terminals (C11 to Cn2) connected to the remaining unit coils, respectively.

That is, the changeover switch S11-Sn1 may be provided to each of the input terminals C12 to Cn1 which are not connected to the output terminals Co1 to Co2 among the input terminals C11 to Cn2.

At this time, each of the changeover switches S11-Sn1 is connected to one of the input terminal and the output terminal corresponding to the adjacent unit coils. At this time, each of the changeover switches S11-Sn1 may be kept open as occasion demands.

For example, when the switch unit 116 is configured to connect a plurality of unit coils 114-1 to 114-n in series, as shown in FIG. 3, each of the plurality of unit coils 114-1 to 114- (N-1) 2) provided in the input terminals C12, C22, ..., C (n-1) 2 connected to the other terminals And connected to the input terminals C21, ..., Cn1 connected to the unit coil.

At this time, the changeover switches S21 to Sn1 provided on the input terminals C21 to Cn1 connected to the unit coils 114-1 to 114-n are kept open .

When only a part of the plurality of unit coils 114-1 to 114-n is serially connected, the changeover switch provided at the input terminal connected to the other end of the last unit coil can be switched to be connected to the output terminal C02 have.

For example, when only the upper two unit coils 114-1 and 114-2 among the plurality of unit coils 114-1 to 114-n are serially connected, an input terminal connected to the other end of the second unit coil 114-2, The changeover switch S22 provided in the switch C22 may be switched to be connected to the output terminal C02.

4, the plurality of unit coils 114-1 to 114-n may be connected in parallel to each other. In the case where the plurality of unit coils 114-1 to 114- the changeover switches S11, S21, ..., Sn1 provided in the input terminals C21, ..., Cn1 connected to one side of the unit coils (n) are switched to be connected to the output terminal Co1, (N-1) 2 included in the input terminals C12, C22, ..., C (n-1) 2 connected to the other side of the switches 114-1 to 114- May be switched to be connected to the output terminal Co2.

When only a part of the plurality of unit coils 114-1 to 114-n is connected in parallel, only the changeover switches provided in the input terminals connected to the unit coils constituting the parallel connection are connected to the output terminals C01 and C02, respectively And the changeover switch provided at the input terminal connected to the unit coil which does not constitute the remaining parallel connection can be kept open.

For example, when only the upper two unit coils 114-1 and 114-2 among the plurality of unit coils 114-1 to 114-n are connected in parallel, an input terminal connected to the unit coils 114-1 and 114-2 Only the changeover switches S11, S21 and S22 provided in the input terminals C12, C21 and C22 are switched to be connected to the output terminals Co1 and Co2, and the changeover switch provided in the input terminal connected to the remaining unit coils is kept open .

When the switch unit 116 is configured such that the plurality of unit coils 114-1 to 114-n are connected in series-parallel combination, as shown in FIG. 5, m unit coils 114-1 to 114- -m, 114- (nm) to 114-n are connected in series, and a plurality of m unit coil groups connected in series may be switched so that a plurality of unit coil groups are connected in parallel. Here, the number of unit coils connected in series or in parallel is determined according to the current magnitude of the power line 12.

At this time, the changeover switch S (nm) 1 provided in the input terminal C (nm) 1 connected to one side of the first coil (for example, 114- And the changeover switch Sm2 provided at the input terminal C m2 connected to the other end of the last coil (for example, 114-m) constituting the series connection is connected to the output terminal Co2 Can be switched to be connected.

3, the changeover switch connected to the adjacent coil among the arbitrary coils is switched to be connected to the output terminal Co1, and the changeover switch connected to the adjacent coil to maintain the open state is connected to the output terminal Co2 ). ≪ / RTI >

The sensing module 120 detects a voltage induced from any one unit coil 114b of the plurality of unit coils 114-1 to 114-n and monitors the current state of the power line 12. [ At this time, the sensing module 120 detects the voltage induced from the unit coil 114b, calculates a current corresponding thereto, and calculates the current of the power line 12 according to the turns ratio of the unit coil 114b .

The sensing module 120 controls the switch unit 116 such that at least some of the plurality of unit coils 114-1 to 114-n are connected in series or in parallel according to the voltage detected from the unit coil 114b .

At this time, the sensing module 120 calculates an average value for a predetermined time with respect to the voltage induced from the unit coil 114b, and when the calculated average value is larger than a preset reference value, the plurality of unit coils 114-1 to 114- 114-n may be connected in parallel with each other. Here, the reference value may be set to a voltage value corresponding to the magnitude of the current generated in the power line 12.

For example, when the current of the power line 12 increases greatly as the power consumption increases as in the daytime, the sensing module 120 may include a plurality of unit coils 114-1 to 114- 114-n may be connected in parallel.

Also, when the calculated average value is smaller than the reference value, the sensing module 120 may control the switch unit 116 such that at least a part of the plurality of unit coils 114-1 to 114-n is connected in series.

For example, when the power consumption decreases as the amount of the strategy used decreases at night, the sensing module 120 may include a plurality of unit coils 114-1 through 114-n The switch unit 116 can be controlled to be connected in series.

At this time, the sensing module 120 may determine the number of the plurality of unit coils 114-1 to 114-n that are connected in series, parallel, or series-parallel combination depending on the magnitude of the detected voltage. That is, the sensing module 120 can control the switch unit 116 to configure a plurality of unit coils 114-1 to 114-n in series or in parallel according to the difference between the detected voltage and the reference value have. Here, the sensing module 120 may set a plurality of reference values having different sizes corresponding to the number of parallel, series, or series-parallel mixing configurations of the plurality of unit coils 114-1 to 114-n.

For example, in a state where a predetermined number of the unit coils are connected in series or in parallel, the sensing module 120 includes a plurality of unit coils 114-1 to 114 -n) of the switch unit 116 to increase or decrease the number of the switches.

At this time, the sensing module 120 may increase or decrease the number of serial-parallel configurations of the plurality of unit coils 114-1 to 114-n, instead of increasing or decreasing the number of serial or parallel configurations according to the multi- It is possible to control the switch unit 116 so as to reduce it.

By configuring the plurality of unit coils 114-1 to 114-n in series or in parallel so as to adjust the ratio so as to induce a constant power even when the current of the power line 12 changes, It is possible to reduce the complexity or the capacity of the circuit for the semiconductor integrated circuit, so that the optimum system can be easily implemented and the manufacturing cost can be reduced.

Alternatively, as shown in FIG. 6, the current transformer 110a may be composed of a plurality of current transformers. That is, each of the current transformers 110a-1, 110a-2, ..., 110a-n, and 110b has one coil wound on one magnetic core.

The one current transformer 110b is connected to the sensing module 120 to monitor the current state of the power line 12. The remaining current transformers 110a-1, 110a-2, ..., 110a-n, May be connected to the switch unit 116 and configured in series or in parallel by the sensing module 120.

The power supply apparatus 100 using the current transformer may further include the power generation unit 130 and the power storage unit 140.

The power generation unit 130 may generate power by a voltage derived from the power induction unit 110. The power generation unit 130 may be connected to the output of the switch unit 116 of the power induction unit 110 and may include a power conversion unit 132 and a regulator 136.

The power conversion unit 132 may convert the output of the power induction unit 110 to DC power. For example, the power conversion unit 132 may be a rectifier circuit including a bridge diode, but is not limited thereto. At this time, the power conversion unit 132 may include a smoothing circuit 134 including a capacitor at its output terminal.

The regulator 136 may adjust the power converted by the power conversion unit 132 to be constantly output. The regulator 136 can adjust the output to a level corresponding to the power of the IoT device 14 at a constant level.

The power storage unit 140 may store the power generated by the power generation unit 130. The power storage unit 140 may include a supercapacitor or a battery.

By configuring the unit coils 114-1 to 114-n in series or in parallel according to the current state of the power line 12, the power induction ratio is adjusted, so that the power line provides a constant power can do.

Also, by connecting a plurality of unit coils 114-1 to 114-n in parallel during a high current time of the power line and connecting a plurality of unit coils 114-1 to 114-n in series during a low current time, The power loss for the current time can be minimized and the capacity of the power storage unit 140 for power storage for the low power time can be minimized.

Hereinafter, the operation of the power supply apparatus 100 using the current transformer according to the embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG.

First, the power supply apparatus 100 using the current transformer calculates an average of voltages derived from the unit coil 114b for the sensor, and monitors the current state of the power line 12 (step S601). Here, the sensor unit coil 114b may be shared with any one of the power unit coils.

The sensing module 120 determines whether the calculated average voltage is greater than the reference value Vset in step S602 and determines that the plurality of unit coils 114-1 to 114-n Are connected in parallel (step S603).

If it is determined in step S602 that the average voltage is smaller than the reference value Vset, the sensing module 120 may control the switch unit 116 so that a plurality of unit coils 114-1 to 114- (604).

In this way, the sensing module 120 controls the switching of the switch unit 116 to derive electric power from the plurality of unit coils 114-1 to 114-n, which are configured in series or parallel, And stores it in the power storage unit 140 to supply power to the IoT device 14 (step S605).

On the other hand, when the plurality of unit coils 114-1 to 114-n are connected in parallel or in series, a plurality of unit coils 114-1 to 114-n are formed stepwise according to the difference between the average voltage and the reference value Vset. Can be controlled in parallel or in series.

As shown in FIG. 7, the sensing module 120 calculates a difference between the average voltage and the reference value Vset (step S701).

At this time, the sensing module 120 calculates the number of the plurality of unit coils 114-1 to 114-n having a series or parallel configuration according to the difference between the average voltage and the reference value Vset (step S702) . That is, the sensing module 120 may control the parallel or series number of the plurality of unit coils 114-1 to 114-n to increase or decrease stepwise according to the current state of the current power line 12 .

Next, the sensing module 120 performs switching by controlling the switch unit 116 so that a plurality of unit coils 114-1 to 114-n are configured in parallel or in series according to the calculated number (step S703 ).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: Power supply using a current transformer
110: electric power induction unit 112: magnetic core
114, 114a, 114b, 114-1, 114-2, 114-n:
116: switch unit 120: sensing module
130: power generation unit 132: power conversion unit
134: smoothing circuit 136: regulator
140: Power storage unit 12: Power line
14: IoT device

Claims (11)

A current transformer installed in a power line as a clamp type to induce power and having a plurality of unit coils;
A switch unit connected to each of the plurality of unit coils and switching the unit coils; And
A sensing module for detecting a voltage derived from any one of the plurality of unit coils and controlling the switch unit so that at least a part of the plurality of unit coils is connected in series or in parallel according to the detected voltage for generating a constant power, And a power supply. The method according to claim 1,
Wherein the sensing module calculates an average value for a predetermined time with respect to a voltage induced from any one of the plurality of unit coils, and when the calculated average value is greater than a reference value, A power supply apparatus using a current transformer for controlling a switch unit. 3. The method of claim 2,
Wherein the sensing module controls the switch unit such that at least a part of the plurality of unit coils is connected in series when the calculated average value is smaller than the reference value. The method according to claim 1,
Wherein the sensing module controls the switch unit such that the plurality of unit coils are connected in series, parallel, or series-parallel combination according to the magnitude of the detected voltage. The method according to claim 1,
Wherein the sensing module determines the number of the plurality of unit coils connected in series, parallel, or series-parallel combination depending on the magnitude of the detected voltage. The method according to claim 1,
Wherein the switch unit includes a plurality of input terminals and a pair of output terminals respectively connected to the plurality of unit coils,
An input terminal to which one side of one unit coil is connected and an input terminal to which one side of the other unit coil is connected are connected to the pair of output terminals,
Wherein the changeover switch is provided on the other side of any one of the unit coils, on the other side of the other unit coil, and on each of the remaining unit coils. The method according to claim 1,
A power generator connected to an output of the switch unit to generate power by the induced voltage; And
And a power storage unit for storing the generated power. The power supply apparatus according to claim 7,
A power conversion unit for converting an output of the switch unit into DC power; And
And a regulator for regulating the converted DC power to be constantly output. 8. The method of claim 7,
Wherein the power storage unit includes a supercapacitor or a battery. A power supply for powering an Internet (IoT) device installed in an inaccessible zone,
A current transformer installed in a power line as a clamp type to induce power and having a plurality of unit coils;
A switch unit connected to each of the plurality of unit coils and switching the unit coils; And
A sensing module for detecting a voltage derived from any one of the plurality of unit coils and controlling the switch unit so that at least a part of the plurality of unit coils is connected in series or in parallel according to the detected voltage for generating a constant power, ;
A power generator connected to an output of the switch unit to generate power by the induced voltage; And
And a power storage unit for storing the generated power,
Wherein the power storage unit is connected to the object Internet device by a wire. A plurality of current transformers installed in the power line as a clamp type to induce power;
A switch unit connected to and switching to each of the plurality of current converters; And
And a sensing module for detecting a voltage derived from one of the plurality of current converters and controlling the switch section so that at least a part of the plurality of current converters is connected in series or in parallel according to the detected voltage to generate a constant power A power supply using a current transformer.

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