KR20140125213A - Double-Tuned Filter Design Method for HVDC System - Google Patents

Abstract

The present specification discloses a design method and a design device for a double-tuned filter and a damped type double-tuned filter of HVDC system. To this end, a method for setting a filter parameter according to an embodiment of the present invention, which is a method for setting a filter parameter of a double-tuned filter, comprises the steps of: setting an input parameter corresponding to a double-tuned filter; setting a resonant frequency corresponding to the double-tuned filter; calculating a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonant frequency; calculating an individual harmonic component or total harmonic distortion corresponding to the double-tuned filter based on the temporary filter parameter; determining whether the calculated individual harmonic component or total harmonic distortion is less than or equal to a reference value; and setting the temporary filter parameter as a filter parameter of the double-tuned filter, when the individual harmonic component or total harmonic distortion is less than the reference value as the result of the determination.

Description

A Double-Tuned Filter Design Method for a HVDC System {Double-Tuned Filter Design Method for HVDC System}

 The technology disclosed herein relates to a method and a device for designing a double tuned filter and a damped-type double tuned filter according to characteristics of a HVDC system.

In the HVDC system, the harmonic filter suppresses the harmonics generated in the power conversion through the converter operation into the AC system, and also acts as a reactive power source due to the reactive power consumption. Since most current type HVDC systems operate with 12 pulses, 12n ± 1 characteristic harmonics such as 11, 13, 23, and 25 are generated. In particular, 11th and 13th harmonics are large. Car / 13th Double Tuned Filter (DTF) is used.

In the current type HVDC system, the converter usually operates with 12 pulses. The 80kV 60MW HVDC system currently installed in Jeju Island is also composed of 12 pulse converters using two 6 pulse group serial connection.

In the HVDC system, a double-tuned filter (DTF) is widely used as a harmonic filter because it has the advantage that only one switchgear is required while occupying less space than a single tuned filter. The equations for the series-parallel impedance of the filter can be used.

There is a problem that the DTF design is not an accurate, efficient, and formalized method or method because passive elements included in the DTF are calculated by passive calculation based on the design rating, performance, and the like.

SUMMARY OF THE INVENTION The object of the present invention is to provide a design method and a design apparatus of a double tuned filter and a damped-type double tuned filter according to characteristics of a HVDC system.

According to another aspect of the present invention, there is provided a method of setting a filter parameter of a double-tuned filter, comprising: setting an input parameter corresponding to the double-tuned filter; Setting a resonance frequency corresponding to the double-tuned filter; Calculating a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency; Calculating individual harmonic components or total harmonic distortion corresponding to the double-tuned filter based on the temporary filter parameters; Determining whether the calculated individual harmonic component or total harmonic distortion is less than a reference value; And setting the temporary filter parameter as a filter parameter of the double-tuned filter when the individual harmonic component or the total harmonic distortion is smaller than the reference value as a result of the determination.

As an example related to the present specification, if the individual harmonic component or the total harmonic distortion factor is greater than the reference value, the method further includes a step of resetting the resonance frequency and returning to the step of calculating the temporary filter parameter .

As an example associated with this disclosure, the resetting of the resonant frequency may be reset based on the filtering frequency that should be filtered by the double-tuning filter.

In one example associated with the present disclosure, the filtering frequency includes a first filtering frequency and a second filtering frequency that is greater than the first filtering frequency, and the resonant frequency is less than the first filtering frequency, Lt; RTI ID = 0.0 > frequency. ≪ / RTI >

As an example related to the present specification, the resonant frequency may be reset in a direction increasing by a frequency of a predetermined interval from the first filtering frequency.

As an example related to the present specification, the input parameter may include at least one of a rated voltage of a load or a system connected to the double-tuning filter, a reactive power to be compensated by the double-tuning filter, and a filtering frequency .

As an example related to the present specification, the double-tuned filter may be connected to an AC system of a High Voltage Direct Current (HVDC) system.

As an example related to the present specification, the reference value may be defined by IEEE Std. Lt; RTI ID = 0.0 > 519 < / RTI >

In one embodiment of the present invention, the reference value corresponding to the individual harmonic component is 1.5% of a fundamental frequency component corresponding to a load or a system connected to the double-tuned filter, and the reference value corresponding to the full- 2,5%.

As an example related to the present specification, the double-tuning filter includes a first LC circuit portion in which a first capacitor and a first inductor are connected in series; And a second LC circuit part connected in parallel with the second capacitor and the second inductor, wherein the first LC circuit part and the second LC circuit part are connected in series, and the resonance frequency is a parallel resonance frequency corresponding to the second LC circuit part Frequency.

As an example related to the present specification, the temporary filter parameter or the filter parameter of the double-tuned filter may include a capacitance value of the first capacitor, an inductance value of the first inductor, a capacitance value of the second capacitor, The inductance value of the inductance value.

As an example related to this specification, the double-tuning filter further comprises a damping resistor connected in parallel to the second LC circuitry, the step of setting the damping resistor; And returning to the step of resetting the resonance frequency and the damping resistance and calculating the temporary filter parameter when the individual harmonic component or the total harmonic distortion is larger than the reference value as a result of the determination .

As an example related to the present specification, the temporary filter parameter may be calculated based on the input parameter, the resonance frequency, and the damping resistance.

As an example related to the present specification, the damping resistor may be reset in a direction that increases between the lower limit damping resistance value and the upper limit damping resistance value.

According to an aspect of the present invention, there is provided an apparatus for setting a filter parameter,

A filter parameter setting apparatus for setting a filter parameter of a double-tuned filter, comprising: an input unit for receiving an input parameter corresponding to the double-tuned filter; And a resonance frequency setting unit that sets a resonance frequency corresponding to the double-tuned filter, calculates a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency, And sets the temporary filter parameter as a filter parameter of the double-tuned filter when the individual harmonic component or the total harmonic distortion is smaller than a reference value, and if the individual harmonic component or the total harmonic distortion is smaller than the reference value, And resetting the resonance frequency to release the temporary filter parameter when the individual harmonic component or the total harmonic distortion factor is larger than the reference value.

According to the method and apparatus for setting the filter parameters of the double-tuned filter according to the embodiment disclosed herein, the double-tuned filter parameter is calculated using the resonance frequency of the double-tuned filter as a variable, and based on the calculated filter parameter Determining a final resonant frequency based on the calculated performance parameters and determining a final filter parameter of the double tuned filter based on the finally determined resonant frequency, There is an advantage in that it is possible to provide a design method or design apparatus for a stylized double-tuned filter.

1 is a block diagram showing a general HVDC (High Voltage Direct Current) system.
2 is a diagram showing a harmonic equivalent model corresponding to a HVDC system in which a harmonic filter is inserted.
3 is an exemplary diagram showing a design method of a double-tuned filter using an equivalent circuit scheme.
4 is a flowchart illustrating a method of setting a filter parameter of a double tuned filter according to an embodiment disclosed herein.
5 is a block diagram of a filter parameter setting apparatus of a double tuned filter according to an embodiment disclosed herein.
6 is an exemplary diagram illustrating a double tuned filter design algorithm according to the first embodiment disclosed herein.
FIG. 7 is an exemplary diagram illustrating a damped-type double tuned filter design algorithm according to the second embodiment disclosed herein.
8 and 9 are exemplary diagrams illustrating HVDC system modeling in accordance with one embodiment disclosed herein.
FIGS. 10 to 15 are illustrations showing experimental results of the HVDC system. FIG.

Although the technology disclosed in this specification describes only the air conditioner including the power conversion device, the power conversion device can be similarly used for other electric devices including a compressor and a motor.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the scope of the technology disclosed herein. Also, the technical terms used herein should be interpreted as being generally understood by those skilled in the art to which the presently disclosed subject matter belongs, unless the context clearly dictates otherwise in this specification, Should not be construed in a broader sense, or interpreted in an oversimplified sense. In addition, when a technical term used in this specification is an erroneous technical term that does not accurately express the concept of the technology disclosed in this specification, it should be understood that technical terms which can be understood by a person skilled in the art are replaced. Also, the general terms used in the present specification should be interpreted in accordance with the predefined or prior context, and should not be construed as being excessively reduced in meaning.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In this specification, the terms "comprising ", or" comprising ", etc. should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps.

Furthermore, terms including ordinals such as first, second, etc. used in this specification can be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals denote like or similar elements, and redundant description thereof will be omitted.

Further, in the description of the technology disclosed in this specification, a detailed description of related arts will be omitted if it is determined that the gist of the technology disclosed in this specification may be obscured. It is to be noted that the attached drawings are only for the purpose of easily understanding the concept of the technology disclosed in the present specification, and should not be construed as limiting the spirit of the technology by the attached drawings.

Normally HDVC  System and Double sync  Explanation of how to design the filter

1 is a block diagram showing a general HVDC (High Voltage Direct Current) system.

The HVDC system shown in FIG. 1 shows a general double tuned filter (DTF) installed in an 80 kV class HVDC system. The 80 kV HVDC system has a typical anode system configuration.

A characteristic of the 80 kV HVDC system is that the two poles are composed of the same 12-pulse converter.

These HVDC converters can generate harmonic currents above a specified value. Hence, without filtering, harmonic currents can distort AC voltage and interfere with normal system operation.

Harmonic filters can be used to make harmonic currents flow by installing a parallel line with a small impedance so that distortion of the AC voltage can be accommodated within a range that can accommodate the AC voltage.

The 12-pulse converter can have a characteristic harmonic of 12n ± 1. Therefore, the harmonic components required for the filter may be 11th, 13th, 23rd and 25th order components.

Higher order higher harmonic components can be attenuated by a high-pass filter.

Referring to FIG. 1, in an 80-kV HVDC system, an 11th / 13th order double-tuned filter for compensating 17Mvar reactive power and a 24th high-pass filter for compensating 17Mvar reactive power Can be used.

In the double-tuned filter, one high-voltage capacitor bank and a low-voltage air core reactor are connected in series, and a low-voltage capacitor bank and an air core reactor are connected in parallel. The harmonic filter can serve to supply reactive power to the system at 60 Hz.

2 is a diagram showing a harmonic equivalent model corresponding to a HVDC system in which a harmonic filter is inserted.

Referring to FIG. 2, the current type HVDC converter absorbs the reactive power from the AC system, and therefore, it is necessary to supply the reactive power required by the converter through the harmonic filter.

This HVDC converter can be modeled as a constant current harmonic power source at the AC terminal and a constant voltage harmonic power source at the DC terminal. Since the harmonic filter plays a role of suppressing the harmonic wave generated from the HVDC converter into the AC system, A harmonic equivalent model using a constant current harmonic power source can be used.

Where In is the harmonic current generated from the HVDC converter, Ifn and Isn are the harmonic currents flowing into the filter and AC system, respectively. Zfn and Zsn denote the harmonic impedances of the filter and the AC system, respectively, and Vsn denotes the harmonic voltage of the AC system.

The performance of a harmonic filter depends on the admittance value of the AC system, and since the admittance of such a system varies with the state of the actual power system, it is very difficult to know the correct admittance value at a given frequency. Therefore, it is possible to determine the harmonic filter design by plotting the admittance according to a given frequency on a complex plane with the admittance angle as a boundary.

3 is an exemplary diagram showing a design method of a double-tuned filter using an equivalent circuit scheme.

Referring to FIG. 3, there is a need to consider harmonic distortion, system reliability, cost, and the like when designing an AC filter (or a harmonic filter) in an HVDC system.

Since a harmonic filter requires a cost per one bank, it is preferable to use two single-tuned filters to remove two harmonics as shown in FIG. 3 (a) (bank) is economically advantageous because it utilizes less space.

A damped-type double tuned filter including a damping resistor R connected in parallel to the parallel LC resonance tank may also be used (FIG. 3 (c)).

The equivalent circuit approach can be a relatively easy approach when designing a double-tuned filter.

In order to design the double-tuned filter, first, the amount of reactive power to be compensated for is distributed equally to each single-tuned filter, and parameter values of each single-tuned filter can be selected.

In selecting the parameter value of the single-tuned filter, the magnitude of the voltage applied to the filter and the amount of reactive power to be compensated by the filter may be determined.

In this case, since the capacitor and the inductor are connected in series in the series LC filter of the filter, the reactance of the filter can be a difference between the reactance of the capacitor and the reactance of the inductor.

 On the other hand, at the harmonic of the h-th order to be eliminated, the impedance of the filter as a whole must be zero, so that the reactance of the capacitor is equal to the inductor's reactance multiplied by the square of h.

The filter parameters can be obtained by the following equation (1).

 The parameter values (C1, C2, L1, L2) of the double-tuned filter of Equation (1) are calculated using the parameter values (Ca, Cb, La, Lb) of each single- ) Can be obtained.

The HVDC converter generates a harmonic current of more than a specified value, so that a harmonic filter is installed to flow the harmonic current so that the distortion of the AC voltage is within the acceptable range. can do.

The 12-pulse converter has a characteristic harmonic of 12n ± 1. Therefore, the harmonic components required for the filter are 11th, 13th, 23rd and 25th components. Higher order higher harmonic components can be attenuated by a high-pass filter.

In an 80 kV HVDC system, an 11th / 13th double-tuned filter that compensates for 17Mvar reactive power and a 24th harmonic high-pass filter that compensates for 17Mvar reactive power can be used.

A double-tuned filter can have one high-voltage capacitor bank and a low-voltage air core reactor in series, and a low-voltage capacitor bank and an air core reactor in parallel.

The harmonic filter serves to supply reactive power to the system at 60 Hz. Therefore, the terminals of the rectifier and the inverter absorb the reactive power in proportion to the active power exchanged between the converter and the AC system. The harmonic filter uses a capacitor, so it can supply the reactive power required by the converter. If the reactive power from the filter is not sufficiently compensated, the AC voltage at the terminal may not be large enough to allow the converter to operate normally.

 The HVDC converter, on the other hand, can be modeled as a constant-voltage harmonic power supply at the dc end and a constant-current harmonic power supply at the ac output. Modeling for harmonic analysis is needed at the AC terminal because it is one of the roles of the filter to prevent the harmonics from the HVDC converter from entering the system.

Where the filter and the power system (e.g., the AC system) coupled to the filter may be represented or modeled as an impedance.

Using the model of FIG. 2, it is possible to design the filter after determining the degree of harmonic current flowing in the converter and the harmonic characteristics of the resulting voltage.

In this filter design, the equivalent circuit approach is a relatively easy approach when designing a double-tuned filter. In order to design a double-tuned filter, first, the amount of reactive power to be compensated for is appropriately distributed to each single-tuned filter, and the parameter value of each single-tuned filter can be selected.

At this time, parameter values of the double-tuned filter of Equation (1) can be obtained by using the parameter values of the selected single-phase tuning filters.

The double-tuned filter using the above-described equivalent circuit method can change the resonance frequency by varying the ratio of the reactive power to be divided.

However, dividing the reactive power appropriately to cause the resonance at a specific frequency may have a problem in that the resonance frequency does not enter the input parameter, so that it is not easy to adjust the filtering and the resonance frequency.

If the resonance frequency adjustment is not easy, there is a difficulty in designing because the order of the filter to be tuned is changed every time according to the division of the reactive power amount, and the adjustment of the impedance characteristic of the filter to be adjusted according to the system impedance characteristic may not be easy.

Therefore, in order to solve the above-described problems, the technology disclosed in the present specification has a problem in that it is necessary to calculate a double-tuned filter parameter with the resonance frequency as a parameter and to calculate a performance parameter (for example, A total harmonic distortion), determining a final resonant frequency based on the calculated performance parameters, and based on the finally determined resonant frequency, a final filter of the double-tuned filter It is possible to provide a method and a device for designing a precise, efficient, and well-formed double-tuned filter.

Hereinafter, a method and apparatus for designing a filter parameter of a double-tuned filter according to an embodiment disclosed herein will be described with reference to FIGS. 4 and 5. FIG.

The work disclosed herein In the embodiment  How to set filter parameters according to

The method of setting a filter parameter according to an embodiment disclosed herein is a method of setting a filter parameter of a double-tuned filter, comprising: setting an input parameter corresponding to the double-tuned filter; Calculating a corresponding resonance frequency, calculating a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency, calculating an individual harmonic corresponding to the double- Component or total harmonic distortion; determining whether the calculated individual harmonic component or the total harmonic distortion is less than or equal to a reference value; and if the individual harmonic component or total harmonic distortion is less than the reference value , The temporary filter parameter is set to a filter wave of the double- It may comprise the step of setting a meter.

According to one embodiment, the method further comprises the step of, when it is determined that the individual harmonic component or the total harmonic distortion factor is greater than the reference value, re-establishing the resonant frequency and calculating the temporary filter parameter As shown in FIG.

Also, according to one embodiment, the resetting of the resonant frequency may be reset based on the filtering frequency to be filtered by the double-tuned filter.

Also, according to one embodiment, the filtering frequency includes a first filtering frequency and a second filtering frequency that is greater than the first filtering frequency, and the resonant frequency is a value between the first filtering frequency and the second filtering frequency Lt; RTI ID = 0.0 > frequency. ≪ / RTI >

According to an embodiment, the resonant frequency may be reset in a direction that increases by a predetermined frequency from the first filtering frequency.

Further, according to one embodiment, the input parameter may include at least one of a rated voltage of a load or a system connected to the double-tuned filter, a reactive power to be compensated by the double-tuned filter, and a filtering frequency .

Also, according to one embodiment, the double-tuned filter may be connected to an AC system of a High Voltage Direct Current (HVDC) system.

Further, according to one embodiment, the reference value may be determined by IEEE Std. Lt; RTI ID = 0.0 > 519 < / RTI >

According to an embodiment, the reference value corresponding to the individual harmonic component is 1.5% of a fundamental frequency (wF) component corresponding to a load or a system connected to the double-tuned filter, and the reference value corresponding to the total harmonic distortion The reference value may be 2,5%.

According to an embodiment, the double-tuned filter further comprises: a first LC circuit part in which a first capacitor and a first inductor are connected in series; And a second LC circuit portion in which a second capacitor and a second inductor are connected in parallel.

Here, the first LC circuit portion and the second LC circuit portion may be connected in series, and the resonance frequency may be a parallel resonance frequency corresponding to the second LC circuit portion.

According to still another embodiment of the present invention, the temporary filter parameter or the filter parameter of the double-tuned filter includes at least one of a capacitance value of the first capacitor, an inductance value of the first inductor, a capacitance value of the second capacitor, The inductance value of the inductance value.

Also, according to one embodiment, the double-tuning filter may further include a damping resistor connected in parallel to the second LC circuit portion.

In this case, according to an embodiment, a method of setting a filter parameter includes: setting the damping resistance; and when the individual harmonic component or the total harmonic distortion is larger than the reference value as a result of the determination, resetting the resonance frequency and the damping resistance And returning to the step of calculating the temporary filter parameter.

According to a modified embodiment, the temporary filter parameter may be calculated based on the input parameter, the resonance frequency, and the damping resistance.

Further, according to one embodiment, the damping resistance may be reset in a direction that increases between a lower limit damping resistance value and an upper limit damping resistance value.

4 is a flowchart illustrating a method of setting a filter parameter of a double tuned filter according to an embodiment disclosed herein.

Referring to FIG. 4, a method of setting a filter parameter of a double tuned filter according to an embodiment disclosed herein may be performed as follows.

First, an input parameter corresponding to the double-tuned filter can be set (S110).

Next, the resonance frequency corresponding to the double-tuned filter can be set (S120).

Next, a temporary filter parameter corresponding to the double-tuned filter may be calculated based on the input parameter and the resonance frequency (S130).

Next, the individual harmonic component or the total harmonic distortion corresponding to the double-tuned filter may be calculated based on the temporary filter parameter (S140).

Next, it is determined whether the calculated individual harmonic component or the total harmonic distortion is less than a reference value (S150).

As a result of the determination, if the individual harmonic component or the total harmonic distortion factor is smaller than the reference value, the temporary filter parameter may be set as a filter parameter of the double-tuned filter (S160).

If it is determined that the individual harmonic component or the total harmonic distortion is greater than the reference value, the resonant frequency may be reset and the process may return to the step of calculating the temporary filter parameter (S170).

Specifically, the method for setting the filter parameters described above will be described. First, an input parameter corresponding to the double-tuned filter is set (or input) in order to set (or determine or detect) an optimum filter parameter corresponding to the double- .

The input parameter may be a parameter related to the rated or target performance of the double-tuned filter (in this sense, the input parameter may be a performance parameter, a product specification or a design specification of the double-tuning filter).

According to one embodiment, the input parameter may include at least one of a rated voltage of a load or a system connected to the double-tuned filter, a reactive power to be compensated by the double-tuned filter, and a filtering frequency.

Here, the load or the system connected to the double-tuned filter may be a power system of the High Voltage Direct Current (HVDC) system (for example, AC system).

The filtering frequency may be a frequency that should be filtered by the double-tuning filter.

According to one embodiment, the filtering frequency may include a first filtering frequency w1 and a second filtering frequency w2 that is greater than the first filtering frequency.

For example, when the harmonic components to be filtered are the 11th and 13th harmonic components described above, the first filtering frequency is a frequency corresponding to the eleventh harmonic component, and the second filtering frequency is the 13th harmonic component As shown in FIG.

Next, a resonance frequency corresponding to the double-tuned filter may be set (or input).

According to one embodiment, the setting of the resonance frequency may be set based on a filtering frequency to be filtered by the double-tuned filter.

For example, the resonant frequency may be set to a frequency between the first filtering frequency and the second filtering frequency.

Specifically, the resonance frequency setting step may be an initial value of the resonance frequency, which is an initially inputted resonance frequency for setting a filter parameter. For example, the resonance frequency may be set (or input) to the first filtering frequency as an initial value.

Next, it is possible to calculate a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency.

According to one embodiment, the temporary filter parameter or the filter parameter of the observer filter finally determined (or set) may mean a value corresponding to the passive element corresponding to the double-tuning filter.

For example, the double-tuned filter includes a first LC circuit portion in which a first capacitor and a first inductor are connected in series, and a second LC circuit portion in which a second capacitor and a second inductor are connected in parallel, The second LC circuitry may be in the form of a series connection.

In this case, the temporary filter parameter or the filter parameter of the double-tuned filter may include at least one of a capacitance value of the first capacitor, an inductance value of the first inductor, a capacitance value of the second capacitor, and an inductance value of the second inductor. One may be included.

In this case, the resonance frequency may be a parallel resonance frequency corresponding to the second LC circuit portion.

According to one embodiment, when the input parameter is the rated voltage of the system (or power system) connected to the double-tuned filter, the reactive power to be compensated by the double-tuned filter, and the filtering frequency, The filter parameter of the double tuned filter can be calculated (or determined or detected) by the following equation (2).

Where V is the rated voltage (or the rated voltage of the power system), wF is the fundamental frequency (or the frequency of the fundamental wave component of the power system) w1 and w2 are tuning frequencies (or filtering frequencies), and wp is a parallel resonance frequency.

Next, the individual harmonic components or the total harmonic distortion corresponding to the double-tuned filter can be calculated based on the temporary filter parameters.

According to one embodiment, the individual harmonic component may be a harmonic component corresponding to the harmonic current generated by the HVDC converter included in the HVDC system.

The total harmonic distortion may be a THD corresponding to the harmonic current, which will be apparent to those skilled in the art.

Next, it is possible to determine whether the calculated individual harmonic component or the total harmonic distortion factor is less than or equal to a reference value

The reference value may be determined on the basis of the performance, specification or design specification required for the double-tuned filter.

For example, the reference value may be obtained from IEEE Std. Lt; RTI ID = 0.0 > 519 < / RTI >

Also, for example, the reference value corresponding to the individual harmonic component is 1.5% of the fundamental frequency component corresponding to the load or the system connected to the double-tuned filter, and the reference value corresponding to the total harmonic distortion is 2, 5%.

According to an embodiment, when the individual harmonic component or the total harmonic distortion factor is smaller than the reference value, the temporary filter parameter is set to a filter parameter of the double-tuned filter (or a filter parameter finally determined or set) .

According to an embodiment, when the individual harmonic component or the total harmonic distortion factor is larger than the reference value, the resonant frequency may be reset and the provisional filter parameter may be calculated.

According to another embodiment, the double-tuning filter may further include a damping resistor connected in parallel to the second LC circuit portion.

In this case, the double-tuned filter may be referred to as a damped-type double tuned filter. An exemplary circuit diagram of the Damped-type Double Tuned Filter may be as shown in FIG. 3 (c).

According to another embodiment of the present invention, there is provided a method of setting a filter parameter, the method comprising: setting the damping resistor; and resetting the resonance frequency and the damping resistance when the individual harmonic component or the total harmonic distortion is greater than the reference value, And returning to the step of calculating the temporary filter parameter.

According to a modified embodiment, the temporary filter parameter may be calculated based on the input parameter, the resonance frequency, and the damping resistance.

According to another embodiment, the damping resistance may be reset in a direction that is increased between a lower limit damping resistance value and an upper limit damping resistance value.

To be more specific, a method of setting a filter parameter according to another embodiment will be described. First, the rated voltage of a power system, which is an input parameter of a harmonic filter having a Damped-type Double Tuned Filter type, a reactive power compensation value to be compensated, You can set the filtering frequency.

Next, an initial value of the parallel resonance frequency of the harmonic filter and an initial value of the damping resistance value can be set.

The first capacitor, the first inductor, the second capacitor, and the second inductor of the first LC circuit portion, which are temporary filter parameters, based on the input parameter, the parallel resonance frequency, or the damping resistance.

The individual harmonic component (or the voltage of the harmonic component) or THD can be calculated based on the calculated temporary parameter.

If the individual harmonic component or THD is less than or equal to the predetermined (or preset) reference value, the temporary parameter may be determined as the filter parameter of the final double tuning filter process).

In the opposite case, it is possible to return to the step of resetting at least one of the damping resistance and the resonance frequency to calculate the temporary filter parameter (processing in the case of the reference value dissatisfaction).

According to the modified embodiment, the processing in the case of the satisfaction of the reference value and the processing in the case of the unsatisfactory reference can be distinguished based on whether the individual harmonic component or the THD is within the reference range.

The work disclosed herein In the embodiment  The filter parameter setting device

The filter parameter setting apparatus according to an embodiment disclosed herein may be implemented as a part or a combination of the configurations or steps included in the embodiments described above or may be implemented as a combination of the embodiments, The redundant portion can be omitted for the sake of clarity of the filter parameter setting apparatus according to the example.

The apparatus for setting a filter parameter according to an embodiment disclosed herein includes a filter parameter setting device for setting a filter parameter of a double-tuned filter, the filter parameter setting device comprising: an input unit for receiving input parameters corresponding to the double- A resonance frequency corresponding to the double-tuned filter is set, a temporary filter parameter corresponding to the double-tuned filter is calculated on the basis of the input parameter and the resonance frequency, And sets the temporary filter parameter as the filter parameter of the double-tuned filter when the individual harmonic component or the total harmonic distortion is smaller than the reference value, and the individual harmonic component or the total harmonic distortion If the harmonic component or the total harmonic distortion factor is larger than the reference value And a control unit for resetting the resonance frequency to restore the temporary filter parameter.

5 is a block diagram of a filter parameter setting apparatus of a double tuned filter according to an embodiment disclosed herein.

The filter parameter setting apparatus 100 may be implemented as any display device, a video display device, a terminal, and an application executing and setting device to which the technical idea of the technology disclosed herein may be applied.

For example, the techniques disclosed herein may be applied to various applications such as a digital television (TV), a smart TV, a smart phone, a portable terminal, a mobile terminal, a personal digital assistant ), A PMP (Portable Multimedia Player) terminal, a personal computer, a notebook computer, a Wibro terminal, an IPTV terminal, a digital broadcasting terminal, a telematics terminal, a navigation terminal, an AVN A navigation terminal, a television, a 3D television, an audio / video (A / V) system, a home theater system, an information providing center, a call center, .

Referring to FIG. 5, an apparatus 100 for setting a filter parameter of a double-tuned filter according to an embodiment disclosed herein may include an input unit 110 and a control unit 120.

In addition, the filter parameter setting apparatus 100 of the double-tuned filter according to the embodiment disclosed herein may further include a memory (not shown) and a display unit (not shown).

Hereinafter, the components will be described.

The input unit 110 may receive input parameters corresponding to the double-tuned filter.

According to one embodiment, the input unit 110 may generate input data for controlling the operation of the filter parameter setting apparatus 100 by a user. The input unit 110 may include a key pad dome switch, a touch pad (static / static), a jog wheel, a jog switch, and the like. Particularly, when the touch pad has a mutual layer structure with the display unit, it can be called a touch screen.

In addition, according to an embodiment, the input unit 110 serves as an interface with all the external devices connected to the filter parameter setting apparatus 100. For example, the input unit 110 may include a wired / wireless headset port, an external charger port, a wired / wireless data port, a memory card port, a port for connecting a device having an identification module, An input / output (I / O) port, a video I / O (input / output) port, and an earphone port.

The control unit 120 may perform a method of setting a filter parameter to be executed by the filter parameter setting apparatus 100.

In addition, the controller 120 may control the operation of the filter parameter setting apparatus 100 as a whole.

According to one embodiment, the controller 120 may be implemented in the form of micro-controllers, microprocessors, or a microcomputer (MICOM).

The controller 120 may set a resonance frequency corresponding to the double-tuned filter.

In addition, the controller 120 may calculate a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency.

Also, the controller 120 may calculate the individual harmonic component or the total harmonic distortion corresponding to the double-tuned filter based on the temporary filter parameter.

The controller 120 may set the temporary filter parameter as a filter parameter of the double-tuned filter when the individual harmonic component or the total harmonic distortion is smaller than a reference value.

In addition, if the individual harmonic component or the total harmonic distortion factor is greater than the reference value, the controller 120 may reset the resonance frequency and reassign the temporary filter parameter.

The memory may store a program for processing and controlling the control unit 120 and may store input / output data (e.g., input parameters) and intermediate result data calculated or calculated by the control unit 120 Or to store the final result data.

The memory may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g., SD or XD memory), a RAM RAM, Random Access Memory) SRAM (Static Random Access Memory), ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), PROM (Programmable Read-Only Memory) Or a storage medium of at least one type. In addition, the filter parameter setting apparatus 100 may use a web storage that performs a memory storage function on the Internet.

The display unit (or display unit) may display the information processed by the filter parameter setting apparatus 100 or the data input by the input unit 110 and output the displayed information.

The display unit may be a liquid crystal display, a thin film transistor-liquid crystal display, an organic light-emitting diode, a flexible display, a 3D display, As shown in FIG. There may be two or more display units according to the implementation of the filter parameter setting apparatus 100.

(Hereinafter, referred to as a 'touch screen') in which the display unit and a sensor (hereinafter, referred to as a 'touch sensor') that detects a touch operation form a mutual layer structure It can also be used as a device. The touch sensor may have the form of, for example, a touch film, a touch sheet, a touch pad, or the like.

The touch sensor may be configured to convert a change in a pressure applied to a specific portion of the display unit or a capacitance generated in a specific portion of the display unit into an electrical input signal. The touch sensor can be configured to detect not only the position and area to be touched but also the pressure at the time of touch. If there is a touch input to the touch sensor, the corresponding signal (s) is sent to a touch controller (not shown). The touch controller may process the signal (s) and then transmit the corresponding data to the control unit 120. Thus, the control unit 180 can know which area of the display unit is touched or the like.

1st Example  - Double Tuned Filter  Design Algorithm

The first embodiment disclosed herein may be implemented as a part or a combination of the configurations or steps included in the embodiments described above, or a combination of the embodiments, and the following description will be made on the basis of the filter parameters The overlapping part can be omitted for the clear representation of the setting device.

6 is an exemplary diagram showing a double tuned filter design algorithm (or a method of setting a filter parameter of a double tuned filter) according to the first embodiment disclosed herein.

Referring to FIG. 6, the input parameters of the double-tuned filter may be a design unit of the rated voltage, the reactive power compensation value, the filtering frequency, and the resonance frequency.

The resonant frequency may vary between filtering frequencies.

The THD of each individual harmonic component and voltage can be calculated when the impedance value for each harmonic changes according to the change of the resonance frequency and is analyzed according to the circuit shown in FIG. 3 (b).

If these values violate the regulations, the filter may not be a suitable filter, so the new filter is designed by changing the resonance frequency.

In addition, even if the specified value is satisfied, the design parameters of the filter can be stored and a new filter can be additionally designed at the other resonance frequency since the verification with the PSCAD / EMTDC program is required.

Finally, we can obtain the design parameters of a double-tuned filter that meets the harmonic specifications for all resonant frequencies present between the filtering frequencies. The formula for determining the filter parameters is shown in Equation (2).

Second Example  - Damped - type Double Tuned Filter  Design Algorithm

The second embodiment disclosed herein may be implemented as a part or a combination of the configurations or steps included in the above-described embodiments, or may be implemented as a combination of the embodiments. Hereinafter, the filter parameters according to one embodiment disclosed herein The overlapping part can be omitted for the clear representation of the setting device.

FIG. 7 is an exemplary diagram illustrating a damped-type double tuned filter design algorithm (or a method of setting a filter parameter of a damped-type double tuned filter) according to the second embodiment disclosed herein.

Referring to FIG. 7, if a resonance occurs in the system to generate a harmonic overvoltage or an excessive inrush current flows, it may damage not only the filter but also other components.

In order to prevent such a phenomenon, the damping resistor in the conventional DTF can be added as shown in FIG. 3 (c). The design algorithm of the damped-type double tuned filter is as follows.

 1) Set input parameters such as the rated voltage of the system, the reactive power compensated for the filter, the tuning frequency (or filtering frequency) of the filter and the parallel resonant frequencies required for the existing DTF design.

 2) Set the initial value of the resonance frequency and set the minimum and maximum values considering the grid data and the required reactive power.

 3) Calculate the filter parameter values.

 4) Calculate the individual harmonic voltage and total harmonic distortion (THD).

 5) The individual harmonic voltage and THD values are given in IEEE Std. 519 is satisfied.

If the tolerance level is not met, reset the resistance and resonance frequency and repeat the algorithm from step 2) until the tolerance level is met.

 At this time, the resonance frequency is changed at regular intervals between the tuning frequencies with respect to the changed resistance.

 6) After selecting the resonance frequency for the most stable filter parameter according to each resistance value, the resistance value is determined considering cost and loss.

  In the above algorithm, even if the individual harmonic voltage and the THD value meet the allowable level, the verification step may be additionally provided, and the stability according to all the resonance frequencies present between the tuning frequencies can be determined through the PSCAD / EMTDC program.

For verification of how to set filter parameters HVDC  system modelling  And experimental results

8 and 9 are exemplary diagrams illustrating HVDC system modeling in accordance with one embodiment disclosed herein.

Referring to FIG. 8 and FIG. 9, as described in FIG. 4, the input parameters of the double-tuned filter may be a design unit such as a rated voltage, a reactive power compensation value, a filtering frequency, and a resonance frequency.

As the resonance frequency changes, the impedance value for each harmonic varies, and the THD of each individual harmonic component and voltage can be related to the system impedance.

The harmonic current data is multiplied by the sum of the filter impedances and the current distribution equation of the system impedance, so that the frequency-dependent individual harmonic voltages can be calculated.

An equivalent model for this is shown in Figs. 8 and 9. Fig.

Unlike the HVDC system equivalent model shown in FIG. 2, the equivalent model of the fundamental wave frequency can be separately modeled as shown in FIG. 8 and the equivalent harmonic model corresponding to the second harmonic according to whether the generator is included or not.

In this case, the voltage applied to the filter is calculated by subtracting the product of the fundamental impedance and the fundamental frequency current.

That is, the voltage at which the fundamental harmonic current flows into the system. Thus, THD (Total Harmonic Distortion) value can be finally obtained by using the individual harmonic voltage data of the above order.

FIGS. 10 to 15 are illustrations showing experimental results of the HVDC system. FIG.

FIG. 10 shows the case where the resonance frequency is 11.1, FIG. 11 shows the case where the resonance frequency is 11.8, FIG. 12 shows the case where the resonance frequency is 11.9, And FIG. 15 shows a case of a double tuned filter filter actually installed in a demonstration complex in Jeju Island.

Referring to FIGS. 10 to 15, when the THDs of the individual harmonic components and the voltages are in violation of the specification, the filter is not suitable, so that a new filter can be designed by changing the resonance frequency.

Further, in order to examine stabilization through dynamic simulation on an algorithm for designing THD as an objective function even if the predetermined value is satisfied, verification through the PSCAD / EMTDC program can be additionally performed as shown in FIGS. 10 to 15.

FIGS. 10 to 15 show that the appearance of the voltage increases according to the filter design value when the HVDC is activated.

As shown in FIG. 10, the AC voltage is unstable when the resonance frequency is very close to the filtering frequency and when the resonance frequency is 12.1 or later as shown in FIG.

On the other hand, in FIGS. 11, 12, and 13, in which the resonance frequencies are 11.8, 11.9, and 12, respectively, the voltage is stabilized within one second.

However, in the case of the 12th order, because the number of inductors or capacitors changes according to the aging of the filter or the system, there is a possibility of entering the 12.1-order easily, so that FIG. 11 having the resonance frequency of 11.8 is the optimum design.

In the case of Fig. 15, this is a case of a double tuned filter actually installed in a demonstration complex in Jeju Island, which is an algorithm that can not select the resonance frequency.

As described above, according to the method and apparatus for setting a filter parameter of a double-tuned filter according to an embodiment disclosed herein, the double-tuned filter parameter is calculated using the resonance frequency of the double-tuned filter as a variable, Determining a final resonance frequency based on the calculated performance parameter and determining a final filter parameter of the double-tuned filter based on the finally determined resonance frequency, It is advantageous to provide an efficient and uniformized design method or design apparatus for a double-tuned filter.

The method described above can be implemented in a recording medium that can be read by a computer or similar device using, for example, software, hardware, or a combination thereof.

For example, the above-described method of setting a filter parameter may be implemented in a storage medium storing a program for executing the method.

According to a hardware implementation, the methods described so far can be applied to various types of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays processors, controllers, micro-controllers, microprocessors, and other electronic units for performing other functions.

For example, the methods may be implemented in the controller 120 of the filter parameter setting apparatus 100.

According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. Software code can be implemented in a software application written in a suitable programming language. The software code may be stored in a memory (not shown) of the filter parameter setting apparatus 100 and may be executed by the control unit 120.

The scope of the present invention is not limited to the embodiments disclosed herein, and the present invention can be modified, changed, or improved in various forms within the scope of the present invention and the claims.

100: filter parameter setting device 110: input part
120:

Claims (14)

In a method of setting a filter parameter of a double-tuned filter,
Setting an input parameter corresponding to the double-tuned filter;
Setting a resonance frequency corresponding to the double-tuned filter;
Calculating a temporary filter parameter corresponding to the double-tuned filter based on the input parameter and the resonance frequency;
Calculating individual harmonic components or total harmonic distortion corresponding to the double-tuned filter based on the temporary filter parameters;
Determining whether the calculated individual harmonic component or total harmonic distortion is less than a reference value; And
And setting the temporary filter parameter as a filter parameter of the double tuned filter when the individual harmonic component or the total harmonic distortion factor is smaller than the reference value as a result of the determination . The method according to claim 1,
Further comprising the step of returning to the step of resetting the resonance frequency and calculating the temporary filter parameter when the individual harmonic component or the total harmonic distortion factor is larger than the reference value as a result of the determination How to set filter parameters. 3. The method of claim 2,
The resonance frequency is reset,
Wherein the filter parameter is reset based on a filtering frequency to be filtered by the double-tuned filter. 4. The method of claim 3,
A first filtering frequency and a second filtering frequency greater than the first filtering frequency,
The resonance frequency may be,
Wherein the frequency of the second filtering frequency is reset to a frequency between the first filtering frequency and the second filtering frequency. 5. The resonator according to claim 4,
Wherein the first filtering frequency is reset in a direction increasing by a frequency of a predetermined interval from the first filtering frequency. 2. The method of claim 1,
Wherein the at least one filter includes at least one of a rated voltage of a load or a system connected to the double-tuned filter, a reactive power to be compensated by the double-tuned filter, and a filtering frequency. 2. The duplexer according to claim 1,
A method for setting a filter parameter of a double-tuned filter that is connected to an AC system of a HVDC (High Voltage Direct Current) system. 2. The apparatus of claim 1,
IEEE Std. 519. A method of setting a filter parameter of a double tuned filter, The method of claim 1, wherein the reference value corresponding to the individual harmonic component
1.5% of a fundamental frequency component corresponding to a load or a system connected to the double-tuned filter,
The reference value corresponding to the total harmonic distortion factor may be expressed as:
2.5%. ≪ / RTI > 2. The duplexer according to claim 1,
A first LC circuit portion in which a first capacitor and a first inductor are connected in series; And
A second LC circuit portion having a second capacitor and a second inductor connected in parallel,
Wherein the first LC circuit portion and the second LC circuit portion are connected in series,
The resonance frequency may be,
Wherein the second resonance frequency is a parallel resonance frequency corresponding to the second LC circuit portion. 11. The method of claim 10, wherein the temporary filter parameter or the filter parameter of the double-
A capacitance value of the first capacitor, an inductance value of the first inductor, a capacitance value of the second capacitor, and an inductance value of the second inductor. The dual-tuned filter according to claim 10,
Further comprising a damping resistor coupled in parallel to the second LC circuitry,
Setting the damping resistor; And
And returning to the step of resetting the resonance frequency and the damping resistance and calculating the temporary filter parameter when the individual harmonic component or the total harmonic distortion factor is larger than the reference value as a result of the determination, How to set the filter parameters of the filter. 13. The method of claim 12,
The resonance frequency, and the damping resistance, wherein the input parameter, the resonance frequency, and the damping resistance are calculated based on the input parameter, the resonance frequency, and the damping resistance. 13. The method of claim 12, wherein the damping resistor comprises:
Wherein the first and second damping resistances are reset in a direction increasing between a lower limit damping resistance value and an upper limit damping resistance value.

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