JP5491751B2 - Power quality evaluation system - Google Patents

Description

  The present invention relates to a power quality evaluation system that evaluates deterioration of power quality due to harmonics, voltage fluctuation, voltage imbalance, instantaneous voltage drop, and the like generated in a power system.

  2. Description of the Related Art Conventionally, several techniques have been proposed as a method for managing the power state by analyzing harmonics of electric equipment generated in the power system.

  One technique is to collect a sample of waveforms for each failure factor in advance using a simulated high-voltage distribution line, and analyze harmonic components up to a predetermined order of each sample waveform. And after calculating | requiring the sum total of the average value for every order of a harmonic content rate according to a failure factor, the maximum value and minimum value of the sum total data according to a failure factor are calculated and memorize | stored. Estimate the cause of the ground fault of the high-voltage distribution line based on whether or not the current waveform flowing in the zero phase of the actual high-voltage distribution line is in the range between the maximum and minimum values for each failure factor (Patent Document 1).

  Another technique detects a fluctuation active part and a fluctuation reactive part before and after the transient state of the fundamental wave active power and fundamental wave reactive power in the consumer, and loads the consumer based on the magnitude of the fluctuation, Specify the operating conditions such as turning on / off power factor correction capacitors and transformers.

  In this technology, the current at the time of customer equipment input is frequency-analyzed, the change pattern of the harmonic component that varies with the equipment, which is the waveform pattern of the harmonic component, and the harmonic component ratio changes with time is extracted. It specifies the operating state of the house facilities and the facility where the failure occurs (Patent Document 2).

Japanese Patent Laid-Open No. 06-217451 Japanese Patent No. 3952355

  However, the former technique only identifies the cause of the ground fault of the high-voltage distribution line, and the latter technique mainly identifies the operational state of the customer equipment on / off, and the abnormal harmonics. It is not a power quality evaluation system that estimates failure of load equipment and abnormalities that are precursors to it from the state.

  The present invention has been made in view of the above circumstances, and calculates an actual harmonic component from the amount of electricity such as voltage and current supplied from the power system to the load equipment, and presets the actual harmonic component calculation result. Calculates the harmonic component coincidence with the normal harmonic component, harmonic abnormal harmonic component, etc. that have the possibility of abnormalities, and can detect faults in the load equipment that comprehensively degrade power quality and abnormalities that are a precursor An object is to provide a power quality evaluation system for estimation.

  In order to solve the above-described problems, the power quality evaluation system according to the present invention performs waveform analysis on the amount of electricity such as voltage and current supplied from a power system to a load facility composed of various devices and equipment, and performs harmonic analysis. Harmonic component calculation means for calculating components, a harmonic normal database for storing harmonic normal patterns of a plurality of normal harmonic components at normal times, such as devices and equipment that constitute the load facility, and the harmonics Harmonic component coincidence for calculating the harmonic component coincidence between the actual harmonic component calculation result obtained by the component calculating means and the harmonic normal harmonic components of a plurality of harmonic normal patterns stored in the harmonic normal database A calculation means and a normal harmonic pattern having a low harmonic component coincidence among the harmonic component coincidence calculated by the harmonic component coincidence calculating means, the apparatus included in the load facility, Vessels is a power quality evaluation system and a harmonic error output means for estimating the harmonic normal pattern, outputs or display indicating the possibility of harmonic abnormalities such.

  In addition to calculating the harmonic component coincidence of the normal harmonic component of the harmonic normal pattern, the harmonic component coincidence of the harmonic abnormal harmonic component, the harmonic component coincidence of the load harmonic component, etc. From a comprehensive point of view, it is intended to estimate a failure of a device such as a load facility or equipment that deteriorates the power quality, or an abnormality that is a precursor.

  According to the present invention, the measured harmonic component is calculated from the amount of electricity such as voltage and current supplied from the power system to the load facility, and the measured harmonic component calculation result and a harmonic having a preset possibility of abnormality are calculated. A power quality evaluation system that calculates harmonic component coincidence with normal harmonic components, abnormal harmonic components, etc., and can estimate failure of load equipment and overall abnormalities that worsen power quality. Can be provided.

The system diagram which shows the example of application to the electric power grid | system of the electric power quality evaluation system which concerns on this invention. The schematic block diagram which shows 1st Embodiment of the electric power quality evaluation system which concerns on this invention. The schematic block diagram which shows the other example of 1st Embodiment of the power quality evaluation system which concerns on this invention. The schematic block diagram which shows the further another example of 1st Embodiment of the electric power quality evaluation system which concerns on this invention. The figure explaining the voltage waveform example for two phases between lines which is an example of the amount of electricity. The block diagram which used the FFT process part which is a specific example of a harmonic component calculation means. The figure which shows an example of the measurement harmonic component result calculated by the harmonic component calculation means. Explanatory drawing which shows the example of the several harmonic abnormality pattern which consists of multiple orders estimated with the harmonic abnormality memorize | stored in a harmonic abnormality database. The figure explaining the functional block and processing content of a harmonic component coincidence calculation means. The figure explaining normalization of the harmonic component by a harmonic component coincidence calculation means. The figure explaining the example in which the normalized measurement harmonic component result and the normalized harmonic generator harmonic component correspond. The figure explaining the example from which the normalized actual harmonic component result and the normalized harmonic generator harmonic component are not completely in agreement. The figure explaining the example in which the normalized actual harmonic component result and the normalized harmonic generator harmonic component partially correspond. The figure showing the relationship between the degree of coincidence of the standardization measurement harmonic component calculation result and the standardization harmonic abnormal harmonic component, and the standardization difference total value. The figure showing the relationship between a harmonic component coincidence degree and the standardization difference total value from another viewpoint. The block diagram which shows one specific example of the harmonic abnormality estimation means shown in FIGS. The figure which showed the relationship between a harmonic component coincidence and a harmonic normal / abnormal harmonic component. The figure which shows the example of a display of a harmonic component coincidence, a harmonic normal pattern, a harmonic abnormal pattern, and a harmonic load pattern. The schematic block diagram which shows 2nd Embodiment of the electric power quality evaluation system which concerns on this invention. The figure which shows the example of a display of the time-sequential change of the harmonic component coincidence for every some harmonic abnormality pattern acquired by the result display control means shown in FIG. 19 for every fixed time. The schematic block diagram which shows 3rd Embodiment of the electric power quality evaluation system which concerns on this invention. The block diagram which shows the other example of a harmonic component calculation means. The figure explaining the phase relationship between the voltage vector of the harmonic voltage contained in an electric quantity, and a harmonic current. The schematic block diagram which shows 4th Embodiment of the electric power quality evaluation system which concerns on this invention. The figure explaining the method of specifying a harmonic abnormality generation source from the relationship between a harmonic generation source and a harmonic current. The schematic block diagram which shows 5th Embodiment of the electric power quality evaluation system which concerns on this invention. The figure explaining the harmonic abnormality generation source determination (specification) logic by the harmonic abnormality estimation means shown in FIG. The schematic block diagram which shows 6th Embodiment of the electric power quality evaluation system which concerns on this invention. The figure which shows the alarm transmission system of the alarm which generate | occur | produces from the alarm generation means of FIG. The figure explaining the generating condition of an alarm. The schematic block diagram of the electric power quality evaluation system which newly provided the control command generation | occurrence | production means in the structure shown in FIG. The figure which shows the control command transmission system of the control command which generate | occur | produces from the control command generation | occurrence | production means of FIG. The figure explaining the generation conditions of a control command.

  Prior to the description of embodiments of the present invention with reference to the drawings, the background to the realization of the present invention will be described below.

  A large number of devices and equipment are installed in each building on the power grid bus of the customer connected to the upper commercial power grid. Different devices and equipment are installed. As a result, even if the device and equipment are normal, the harmonic normal pattern of the harmonic normal harmonic component indicating the possibility of harmonic abnormality is generated due to the influence of other devices and equipment, or the power When a plurality of devices and devices are connected in parallel to the system bus, a harmonic load pattern of a load harmonic component that is highly influenced by the load-specific harmonics may be generated. This means that a failure of a load facility that deteriorates power quality or an anomaly that is a precursor to it can be estimated only by the harmonic coincidence of the harmonic normal harmonic components of the harmonic abnormality pattern that has a high possibility of harmonic abnormality. Therefore, it is desirable to comprehensively grasp the harmonic matching degree of the harmonic components and estimate the abnormality of the harmonic components.

  Therefore, the present inventors consider the above situation and evaluate the power quality.

(First embodiment)
FIG. 1 is a system diagram showing an example in which a power quality evaluation system 1 according to the present invention is applied to a power system.
In the power quality evaluation system 1, for example, a measuring device 4 is installed between a bus 2 that receives power from a higher power system and a load facility (including various devices, equipment, etc.) 3. The harmonic component superimposed on the voltage and current is calculated from the amount of electricity 5 including the voltage and current supplied to the load equipment 3 to be operated, and the result of the actual harmonic component calculation and the harmonic component stored in advance are calculated. This is a system that estimates the failure of the load equipment and the abnormality that is a precursor thereof.

FIG. 2 is a schematic configuration diagram showing the first embodiment of the power quality evaluation system 1 according to the present invention. FIG. 2 corresponds to claim 1.
The power quality evaluation system 1 uses a computer to perform software processing according to a certain processing procedure. Functionally, the power quality evaluation system 11, the data recording unit 12, the harmonic component Consistency calculation means 13 and harmonic abnormality estimation means 14 are configured.

  The harmonic component calculation means 11 calculates the harmonic component by analyzing the waveform of the electric quantity 5 such as voltage and current supplied from the higher power system measured by the measuring device 4, and obtains the measured harmonic component calculation result 15. Acquired and sent to the harmonic component coincidence calculation means 13.

  The data recording means 12 stores various data for evaluating the power quality, and is a pattern of a harmonic component (hereinafter referred to as a harmonic normal harmonic component) 16a presumed that the harmonic is normal in advance. A database 17 for storing 21a (hereinafter referred to as a harmonic normal pattern) is provided, and an actually measured harmonic component calculation result 15 acquired by the harmonic component calculation means 11 is stored.

  The harmonic component coincidence calculation means 13 calculates the harmonic component coincidence from the actual harmonic component calculation result 15 and the harmonic normal harmonic component 16a having the harmonic normal pattern 21a having a plurality of orders stored in the database 17. It has a function of calculating 18a.

  The harmonic abnormality estimation means 14 determines the possibility of a harmonic abnormality in the harmonic normal pattern 21a having a lower harmonic component coincidence 18a from the harmonic component coincidence 18a calculated by the harmonic component coincidence calculation means 13. It is estimated that the harmonic normal pattern 21a is shown. That is, the harmonic abnormality estimation means 14 determines a harmonic abnormality from the harmonic component coincidence degree 18a of the harmonic normal pattern 21a, and outputs it as a harmonic abnormality estimation result 20.

FIG. 3 is a schematic configuration diagram showing another example of the first embodiment of the power quality evaluation system 1 according to the present invention. FIG. 3 corresponds to claim 2.
The configuration of the power quality evaluation system 1 is almost the same as that shown in FIG. 2, and the difference is that the types of harmonic patterns stored in the database 17 constituting the data recording means 12 are different. Therefore, in FIG. 3, the same or equivalent parts as in FIG.

  The data recording means 12 stores the actually measured harmonic component calculation result 15 acquired by the harmonic component calculating means 11, and the database 17 stores the harmonic normal harmonics estimated in advance as normal as described above. Harmonic normal pattern 21a of component 16a and pattern (hereinafter referred to as harmonic abnormal harmonic component) 16b of a harmonic component (hereinafter referred to as harmonic abnormal harmonic component) that is presumed to be a malfunction of the device or a harmonic abnormality that is a precursor thereof. 21b (refer to FIG. 8 described later) is stored.

  The harmonic component coincidence calculation means 13 includes a harmonic component coincidence degree 18a between the actual harmonic component calculation result 15 stored in the data recording means 12 and the harmonic component of the harmonic normal harmonic component 16a, and the data recording means 12. And the harmonic component coincidence degree 18b between the harmonic component calculation result 15 and the harmonic component of the harmonic abnormal harmonic component 16b.

  The harmonic abnormality estimation means 14 estimates the harmonic normal pattern 21a having a low harmonic component coincidence 18a as the harmonic normal pattern 21a indicating the possibility of harmonic abnormality, and the harmonic having a high harmonic component coincidence 18b. The abnormal pattern 21b is estimated as a harmonic abnormal pattern 21b having a high possibility of harmonic abnormality.

  The harmonic abnormality estimation means 14 determines a harmonic abnormality from the harmonic component coincidence 18a of the harmonic normal harmonic component 16a and the harmonic component coincidence 18b of the harmonic normal harmonic component 16b, and the determination result is obtained. Output as harmonic abnormality estimation result 20.

FIG. 4 is a schematic configuration diagram showing still another example of the first embodiment of the power quality evaluation system 1 according to the present invention. FIG. 4 corresponds to claim 3.
The configuration of the power quality evaluation system 1 is almost the same as that shown in FIG. 2, and the difference is that the types of harmonic patterns stored in the database 17 constituting the data recording means 12 are different. Therefore, in FIG. 4, the same or equivalent parts as in FIG.

  The data recording means 12 stores the actually measured harmonic component calculation result 15 acquired by the harmonic component calculating means 11, and the database 17 stores the harmonic normal harmonics estimated in advance as normal as described above. The load equipment 3 is parallel to the bus 2 and the harmonic normal pattern 21a of the component 16a, the harmonic abnormal pattern 21b of the harmonic abnormal harmonic component 16b that is estimated to be a malfunction or a harmonic abnormality that is a precursor thereof, and the like. If connected, a pattern (hereinafter referred to as a harmonic load pattern) 21c of a harmonic component (hereinafter referred to as a load harmonic component) 16c estimated as a harmonic unique to those loads is stored.

  Therefore, as the harmonic component coincidence calculation means 13, the harmonic component coincidence degree 18a between the measured harmonic component calculation result 15 stored in the data recording means 12 and the harmonic component of the harmonic normal harmonic component 16a, Similarly, the harmonic component coincidence 18b between the actual harmonic component calculation result 15 stored in the data recording unit 12 and the harmonic component of the harmonic abnormal harmonic component 16b, and the actual harmonic stored in the data recording unit 12 are also stored. The component calculation result 15 and the harmonic component matching degree 18c of the load harmonic component 16c are respectively calculated.

  The harmonic abnormality estimation means 14 determines the possibility of a harmonic abnormality in the harmonic normal pattern 21a having a lower harmonic component coincidence 18a from the harmonic component coincidence 18a calculated by the harmonic component coincidence calculation means 13. The harmonic abnormal pattern 21b having a high harmonic component matching degree 18b is estimated as the harmonic abnormal pattern 21b having a high possibility of harmonic abnormality, and the harmonic component matching degree 18c is further calculated. The high harmonic load pattern 21c is estimated as the harmonic load pattern 21c having a high influence of the harmonic due to the load.

  That is, the harmonic abnormality estimation means 14 includes the harmonic component matching degree 18a of the harmonic normal pattern 21a, the harmonic component matching degree 18b of the harmonic abnormal pattern 21b, and the harmonic component matching degree 18c of the harmonic load pattern 21c. From the above, a harmonic abnormality is determined, and the determination result is output as a harmonic abnormality estimation result 20.

  FIG. 5 is a diagram illustrating an example of a voltage waveform for two phases between lines, which is an example of the amount of electricity.

  In the figure, the horizontal axis represents time and the vertical axis represents voltage. Now, assuming that the voltages for the three phases are Va, Vb, and Vc, the line voltages for the three phases are Vab, Vbc, and Vca. In the example for two phases, the line voltages are Vab and Vbc.

Next, the operation of the power quality evaluation system 1 as described above will be described.
First, FIG. 6 is a diagram for explaining the harmonic component calculation means 11 related to all claims of the present invention. The harmonic component calculation means 11 takes in an electric quantity 5 such as voltage and current supplied to the load facility 3 from the measurement device 4 installed between the bus 2 and the load facility 3 through the transmission system, or measures the measurement device. 4 receives the amount of electricity 5 transmitted through the transmission system from 4 and calculates a component for each order of the harmonics included in the fundamental voltage wave included in the amount of electricity 5. That is, the harmonic component calculation means 11 regards the harmonic component as the sum of each order component, and calculates the harmonic component for each order.

  The most commonly used fast Fourier transformation (FFT) is known as a method for calculating the components for each harmonic order. In the present embodiment, an example is shown in FIG. Harmonic component calculation processing is executed using an FFT processing unit 11a having a high-speed Fourier transform function.

  The harmonics are a collection of sine waves having a frequency n times (n is an integer of 2 or more) of the fundamental wave superimposed on the fundamental wave. The waveform of a general electric quantity including harmonics is a fundamental wave having a commercial frequency as a fundamental frequency and each sine wave (harmonic component) having a frequency that is n times the fundamental frequency (period is 1 / n). It is expressed as the sum of Hereinafter, a sine wave whose primary component is a primary component, a sine wave whose period is 1/2 of the fundamental wave (frequency is twice), a secondary component, and a sine wave whose period is 1/3 of the fundamental wave (frequency is 3 times) A sine wave whose period is 1 / n (frequency is n times) of the fundamental wave is hereinafter referred to as an n-order component.

  Incidentally, the reason for using the FFT processing unit 11a having the high-speed Fourier transform function shown in FIG. 6 as described above is as follows.

  Usually, when harmonics enter the commercial frequency, it is said that the commercial frequency is distorted, and the harmonic component is obtained by Fourier transform etc., but the observation data (measurement data) is discretely sampled from the operating characteristics of the equipment. It can be data. When obtaining harmonic components from such sampling data, it is necessary to use a technique called discrete Fourier transform. In this respect, the FFT processing unit 11a having a high-speed Fourier transform function is a conversion method devised so as to be able to solve the discrete Fourier transform at high speed, and can cope with either continuous or discrete sampling data. .

  The FFT processing unit 11a analyzes the waveform of the quantity of electricity 5 and extracts a harmonic component for each order included in the quantity of electricity 5.

  FIG. 7 is a diagram showing an example of the actually measured harmonic component result calculated by the harmonic component calculating means 11 for the voltage waveform for two phases between lines, using the FFT processing unit 11a for each harmonic order. This is an example of calculating the harmonic component of. The example in the figure shows the harmonic content of Vab and Vbc, with the horizontal axis representing the harmonic order and the vertical axis representing the harmonic content.

Here, the harmonic content is calculated for each order of harmonics and is expressed by the following equation.
Harmonic content (order) = Harmonic magnitude (order) ÷ Fundamental wave size (1)
As described above, the database 17 includes the harmonic normal harmonic component 16a of the harmonic normal pattern 21a, the harmonic abnormal harmonic component 16b of the harmonic abnormal pattern 21b, and the load harmonic of the harmonic load pattern 21c as described above. Although the component 16c is accumulated, as the harmonic abnormal harmonic component 16b, for example, a harmonic abnormal pattern including a plurality of order components and the magnitude (harmonic content) of each order component as shown in FIG. Each pattern is characterized by a combination of order components that are represented by 21b and are estimated to be harmonic abnormalities. Incidentally, FIG. 8 shows three harmonic abnormality patterns 21bA, 21bB, and 21bC as an example.

  By the way, the harmonic abnormality is not only a failure of the device or the apparatus but also often indicates a failure of the device or the apparatus. For this reason, the harmonic abnormality database 17 stores, for example, three harmonic abnormality patterns 21bA, 21bB, and 21bC that are composed of combinations of order components that are signs of failure and the contents of each order component.

  Here, the horizontal axis of the harmonic anomaly pattern 21b shown in FIG. 8 is represented by the harmonic order, and the vertical axis is represented by the harmonic content. The harmonic content is calculated for each harmonic order as described above. Calculated in (1).

  FIG. 9 is a diagram for explaining functional blocks and processing contents of the harmonic component coincidence calculation means 13 (including 13a and 13c; the same applies hereinafter).

  The harmonic component coincidence calculation means 13 is obtained by the normalization calculation processing unit 13a that executes a process of normalizing so that the total of the actual harmonic component calculation results 15 becomes 1, and the normalization calculation processing unit 13a. The standardized result (standardized value) of the actually measured harmonic component calculation result 15 and the value normalized so that the sum of the harmonic components becomes 1 for each harmonic abnormal harmonic component 16b stored in the database 17; And a coincidence degree calculation processing unit 13b for calculating the coincidence degree.

  When the harmonic component coincidence calculation means 13 receives the measured harmonic component calculation result 15, the normalization calculation processing unit 13 a executes the normalization process, and the harmonic components of the respective orders included in the measured harmonic component calculation result 15. Is normalized so that the sum of 1 becomes 1.

  At the time of normalization, a j-th order component (j is a natural number of 2 or more) after normalization is calculated using the following equation (2).

J-order component after normalization = j-th harmonic component before normalization / total value of harmonic components before normalization
(2)
FIG. 10 is a diagram illustrating normalization of harmonic components.

  As the harmonic component, the maximum order of the harmonic abnormal harmonic component 16b in the database 17 may not match the maximum order of the harmonic component in the actually measured harmonic component calculation result 15. For example, although the maximum order of the harmonic component of the actually measured harmonic component calculation result 15 is up to 25th order, the maximum order of the harmonic abnormal harmonic component 16b may be up to 20th order, for example. In such a case, the lower order of both orders, that is, the maximum order 20 of the harmonic anomalous harmonic component 16b having the lowest maximum order is matched, and both harmonic components up to the 20th order are extracted and normalized. . As a result, the denominator of the formula (2) is the total value up to the 20th order of the harmonic components before normalization.

  The coincidence calculation processing unit 13b stores the value after the standardization of the measured harmonic component calculation result 15 (hereinafter referred to as the normalized measured harmonic component calculation result 22; see FIG. 11A) and the database 17. The absolute value of the difference from the value after the standardization of the harmonic abnormal harmonic component 16b (hereinafter referred to as the normalized harmonic abnormal harmonic component 23; see FIG. 11B) is taken for each order, and the equation (3) The total value (hereinafter referred to as the normalized difference total value 24) is calculated as follows.

Total normalized difference 24 = | Second-order component after normalization (actually measured harmonic component calculation result 15) -Second-order component after normalization (harmonic abnormal harmonic component 16b) | + | Third-order component (measured harmonic component calculation result 15) -standardized third-order component (harmonic abnormal harmonic component 16b) | +... + | N-th normalized component (measured harmonic component) Calculation result 15) -nth-order component after normalization (harmonic abnormal harmonic component 16b) |
= | Second order component (standardized actual harmonic component calculation result 22) -second order component (normalized harmonic abnormal harmonic component 23) | + | third order component (standardized actual harmonic component calculation result 22) ) -3rd order component (standardized harmonic abnormal harmonic component 23) | +... + | Nth order component (standardized actual harmonic component calculation result 22) -nth order component (standardized harmonic abnormal harmonic component) Wave component 23) |
...... (3)
From this equation (3), when the normalized measured harmonic component calculation result 22 and the normalized harmonic abnormal harmonic component 23 completely coincide, the normalized difference total value 24 becomes zero.

  FIG. 11 is a diagram illustrating an example in which the normalized actual harmonic component calculation result 22 and the normalized harmonic abnormal harmonic component 23 completely match. That is, the coincidence calculation processing unit 13B, based on the formula (3), when the standardized actual harmonic component calculation result 22 and the standardized harmonic abnormal harmonic component 23 completely match, the standardized difference total The value 24 becomes zero.

  On the other hand, if the normalized measured harmonic component calculation result 22 and the normalized harmonic abnormal harmonic component 23 do not completely match based on the equation (3), the total value of the normalized measured harmonic component calculated result 22 Since the total value of the normalized harmonic abnormal harmonic component 23 is 1 respectively, the normalized difference total value 24 is 2. For example, as shown in FIG. 12, the standardized measured harmonic component calculation result 22 including the third and fifth harmonic components, and the normalized harmonic abnormal harmonic component including the seventh and ninth harmonic components. In the case of 23, the orders are completely inconsistent. However, since both are standardized, the total value of the multiple orders is 1, respectively. As a result, the total value 24 of the normalized difference absolute value is 2.

  FIG. 13 is a diagram illustrating an example in which the normalized actual harmonic component calculation result 22 and the normalized harmonic abnormal harmonic component 23 partially match. In this example, the fifth-order harmonic components match, but the other-order harmonic components do not match. In such a case, out of the total value 1 of the normalized measured harmonic component calculation result 22, the normalized measured harmonic component calculation result 22 having a third harmonic component that does not match is 0.6. Of the total value 1 of the normalized harmonic abnormal harmonic component 23, the normalized harmonic abnormal harmonic component 22 having the seventh harmonic component that does not match is 0.6. As a result, the total value 24 of the normalized difference absolute value is 0.6 + 0.6 = 1.2.

  As described above, the normalized difference absolute value from the case where the normalized measured harmonic component calculation result 22 and the normalized harmonic anomalous harmonic component 23 coincide with each other from when they do not coincide with each other completely. It can be seen that the total value 24 is represented by an intermediate value from 2 (when there is no coincidence) to 0 (when there is no coincidence).

  FIG. 14 is a diagram showing the relationship between the degree of coincidence between the normalized actual harmonic component calculation result 22 and the normalized harmonic abnormal harmonic component 23 and the normalized difference total value 24. As can be seen from this figure, the normalized difference total value 24 of perfect match is 0, and the normalized difference total value 24 of completely mismatch is 2, and when it partially matches, it becomes an intermediate value. It represents.

Here, the definition of the harmonic component coincidence degree 18b (including 18a and 18c) will be considered.
Now, when the normalized measured harmonic component calculation result 22 and the normalized harmonic anomalous harmonic component 23 are completely coincident, 100%, when they are not coincident at all, −100%, and the middle is 0%. This will make it easier to understand.

  Therefore, the conversion equation between the harmonic component matching degree 18b and the normalized difference total value 24 shown in FIG. 15 can be expressed by equation (4). As a result, the result calculated by Expression (4) can be defined as the harmonic component coincidence degree 18 (including 18a and 18c).

Harmonic component coincidence 18 (18a, 18b, 18c) = (1−normalized difference total value 24) × 100 (%) (4)
That is, the harmonic component coincidence calculation means 13 in the embodiment corresponding to claim 1 calculates the harmonic component coincidence 18a with the actually measured harmonic component calculation result 15 for each harmonic normal harmonic component 16a by the formula ( 4) and pass to the harmonic abnormality estimation means 14. In the harmonic component coincidence calculation means 13 in the embodiment corresponding to claim 2, for each harmonic abnormal harmonic component 16b, the harmonic component coincidence 18b with the actually measured harmonic component calculation result 15 is expressed by equation (4). And pass to the harmonic abnormality estimation means 14. In the harmonic component coincidence calculation means 13 in the embodiment corresponding to claim 3, for each load harmonic component 16c, the harmonic component coincidence 18c with the actually measured harmonic component calculation result 15 is calculated by the equation (4). To the harmonic abnormality estimation means 14.

  Therefore, the harmonic abnormality estimation means 14 in the embodiment corresponding to claim 1 is based on the harmonic component coincidence 18a for each harmonic normal harmonic component 16a received from the harmonic component coincidence calculating means 13. The harmonic abnormality estimation means 14 in the embodiment corresponding to claim 2 adds the harmonic component coincidence degree 18b for each harmonic abnormal harmonic component 16b received from the harmonic component coincidence calculation means 13, and The harmonic abnormality estimation means 14 in the embodiment corresponding to 3 adds the harmonic component coincidence 18c for each load harmonic component 16c received from the harmonic component coincidence calculation means 13, and estimates the harmonic abnormality.

  FIG. 16 is a diagram for explaining functional blocks and processing contents of the harmonic abnormality estimation means 14.

  The harmonic abnormality estimation means 14 includes a matching degree rearrangement processing unit 14a and a harmonic abnormality extraction unit 14b.

The degree-of-match rearrangement processing unit 14a performs the following processing for each embodiment of each claim.
Based on the harmonic component coincidence 18 (18a, 18b, 18c) of the harmonic abnormal harmonic component 16, the harmonic normal harmonic component 16a corresponds to claim 2 in the embodiment corresponding to claim 1. In the embodiment, the harmonic abnormal harmonic component 16b is added, and in the embodiment corresponding to claim 3, the load harmonic component 16c is added, and rearrangement is performed. For example, the components are rearranged in descending order of the harmonic component matching degree 18.

The harmonic abnormality extraction unit 14b performs the following processing for each embodiment of each claim.
The harmonic anomaly extraction unit 14b of the embodiment corresponding to claim 1 has the harmonic components of the harmonic normal pattern 21a having the harmonic normal harmonic components 16a rearranged in descending order of the harmonic component matching degree 18a. When the degree of coincidence 18a is low, the pattern 21a estimated to be harmonic abnormality is extracted and output as the harmonic abnormality estimation result 20.

  Next, the harmonic abnormality extraction unit 14 according to the embodiment corresponding to claim 2 includes the harmonic normal pattern 21a having the harmonic normal harmonic components 16a rearranged in order from the highest harmonic component matching degree 18a. The harmonic component matching degree 18a is compared with the harmonic component matching degree 18b of the harmonic abnormal pattern 21b having the harmonic abnormal harmonic component 16b rearranged in order from the highest harmonic component matching degree 18b. If the harmonic component matching degree 18b of the abnormal pattern 21b is relatively higher, it is estimated that the harmonic is abnormal, the harmonic abnormal pattern 21b estimated to be the harmonic abnormal is extracted, and is output as the harmonic abnormal estimation result 20 To do.

  Furthermore, the harmonic abnormality extraction unit 14b according to the embodiment corresponding to claim 3 has the harmonic normal pattern 21a having the harmonic normal harmonic components 16a rearranged in descending order of the harmonic component matching degree 18a. The harmonic component coincidence 18b and the harmonic component coincidence 18c of the harmonic abnormal pattern 21b having the harmonic abnormal harmonic component 16b rearranged in order from the highest in the harmonic component coincidence 18b. The harmonic component matching degree 18c of the harmonic load pattern 21c having the load harmonic component 16c rearranged in order from the higher one is compared, and the harmonic component matching degree 18b of the harmonic abnormal pattern 21b is relatively If it is higher, it is estimated as a harmonic abnormality, and a harmonic abnormality pattern 21b estimated as the harmonic abnormality is extracted and output as a harmonic abnormality estimation result 20.

  FIG. 17A is a diagram for explaining the relationship between the harmonic component matching degree 18a and the normal harmonic component 16a.

  When the harmonic normal patterns 21a corresponding to the harmonic normal harmonic components 16a are arranged from the left in order from the highest harmonic component matching degree 18a, the harmonic component matching degree 18a is obtained as shown in FIG. It is considered that the higher the harmonics are normal, the lower the value is between 100% and -100% and the left side.

  Therefore, the harmonic abnormality extraction unit 14b of the harmonic abnormality estimation means 14 sets the harmonic abnormality extraction threshold value 25, and the harmonic normal harmonics whose harmonic component matching degree 18a is lower than the harmonic abnormality extraction threshold value 25. The normal harmonic pattern 21a having the wave component 16a can be extracted as a harmonic abnormality.

  FIG. 17B is a diagram for explaining the relationship between the harmonic component coincidence 18b and the harmonic abnormal harmonic component 16b.

  When the harmonic abnormal patterns 21b corresponding to the harmonic abnormal harmonic components 16b are arranged in order from the higher harmonic component matching degree 18b from the left side, the harmonic component matching degree 18b is obtained as shown in FIG. It is considered that it is higher between 100% and -100%, and the higher the left side, the higher the harmonic anomaly.

  Therefore, the harmonic abnormality extraction unit 14b of the harmonic abnormality estimation unit 14b sets the harmonic abnormality extraction threshold value 25, and the harmonic abnormality harmonics whose harmonic component matching degree 18b is higher than the harmonic abnormality extraction threshold value 25. The harmonic abnormality pattern 21b having the wave component 16b can be extracted as a harmonic abnormality.

  As the harmonic abnormality extraction threshold 25, a different value is used for each of the harmonic normal pattern 21a and the harmonic abnormality pattern 21b in consideration of the possibility of affecting the power quality through accumulation of experiments and experience. It may be used.

  Accordingly, the harmonic abnormality extraction unit 14b outputs the harmonic abnormality harmonic component 16b existing above the harmonic abnormality extraction threshold value 25 in FIG.

  FIG. 18A is a diagram showing a display example of the harmonic component coincidence degree 18 (18a, 18b, 18c), the harmonic normal pattern 21a, the harmonic abnormal pattern 21b, and the harmonic load pattern 21c. In the figure, the vertical axis represents the harmonic component coincidence 18, and the horizontal axis represents the relationship between the harmonic component coincidence 18 and the patterns 21a to 21c.

  In FIG. 18A, the harmonic normal pattern 21a exists above the harmonic abnormality extraction threshold 25, and the harmonic load pattern 21c is below the harmonic normal pattern 21a. Although 21b is below the harmonic abnormality extraction threshold 25, since the harmonics of the harmonic abnormality pattern 21b are affected by the load harmonics, it can be determined that there is no failure. In other words, it is considered that the load equipment 3 connected to the bus 2 is affected by the nearby load equipment such as a personal computer or a rotating machine, and a harmonic component of an abnormal component is generated.

  On the other hand, in FIG. 18B, the harmonic abnormality pattern 21b exists above the harmonic abnormality extraction threshold 25, and the harmonic normal pattern 21a is below the harmonic abnormality extraction threshold 25. Since the harmonic abnormality pattern 21b is on the upper side of the harmonic normal pattern 21a and the harmonic load pattern 21c, it can be determined that the harmonics of the harmonic abnormality pattern 21b are abnormal and have a possibility of failure.

  Therefore, according to the embodiment as described above, the amount of electricity such as the voltage and current of the consumer who receives power supply from the power system through the transmission system is collected, and the harmonic component which is one of the power quality The degree of coincidence of these measured harmonic components with the harmonic normal harmonic component 16a, harmonic abnormal harmonic component 16b, and load harmonic component 16c stored in advance is calculated, and each of the harmonic components 16a to 16c is calculated. Since the power quality is evaluated from the degree of coincidence and the harmonic abnormality extraction threshold value 25, it is possible to reliably and accurately estimate which harmonic abnormality pattern is deteriorating the evaluation of the power quality.

  Moreover, since the harmonic component coincidence calculation means 13 (13a, 13b, 13c) calculates the coincidence and makes it possible to arrange and display in order of high coincidence, each abnormal pattern 21a to 21c can be displayed in an easy-to-view manner, It can be easily grasped which harmonic abnormal pattern 21a to 21c has the most influence on the power quality.

(Second embodiment: corresponding to claim 5)
FIG. 19 is a configuration diagram in which a result display control unit 31 is provided in place of the harmonic abnormality estimation unit 14 which is one component of the power quality evaluation system 1. These harmonic abnormality estimation means 14 (14a, 14b, 14c) and the result display control means 31 correspond to harmonic abnormality output means in a broad sense.

  Hereinafter, an example in which the result display control unit 31 is provided in the configuration illustrated in FIG. 4 will be described. However, the result display control unit 31 may be provided in the configuration illustrated in FIGS.

  In other words, the power quality evaluation system 1 is provided on the output side of the harmonic component coincidence calculating unit 13 in addition to the harmonic component calculating unit 11, the data recording unit 12, and the harmonic component coincidence calculating unit 13 shown in FIG. The result display control means 31 is newly provided.

  The harmonic component coincidence calculating means 13 calculates the harmonic component coincidence degree 18c of each harmonic normal pattern 21a, each harmonic abnormal pattern 21b, and each harmonic load pattern 21c, for example, a predetermined storage of the data recording means 12 The result is stored in the area and sent to the result display control means 31.

  The result display control unit 31 displays the harmonic component coincidence degrees 18a to 18c for the respective harmonic abnormality patterns 21a to 21c output from the harmonic component coincidence degree calculating unit 13 on the display device 32, and at regular intervals. Returning to the harmonic component calculating means 11, the processing by each of the constituting means 11, 13, 31 is repeatedly executed. As a result, in the predetermined storage area of the data recording means 12, each harmonic normal pattern 21a, each harmonic abnormal pattern 21b, and each harmonic load pattern 21c for each time over a required period (for example, 24 hours). Are stored in time series.

  FIG. 20 is a diagram illustrating a display example of the harmonic component coincidence degree 18c for each of the harmonic abnormality patterns 21aA and 21aB, the harmonic abnormality pattern 21b, and the harmonic load patterns 21cA and 21cB by the result display control unit 31. The vertical axis represents the harmonic component coincidence 18c, and the horizontal axis represents time.

  The example of FIG. 20 is a display example for 24 hours a day. That is, the harmonic component coincidence calculation means 13 uses the harmonics of the harmonic load patterns 21cA and 21cB and the harmonic abnormal pattern 21b as the harmonic abnormal patterns 21aA and 21aB and the harmonic load pattern 21c as the harmonic normal pattern 21a. This is an example in which the component coincidence degree 18c is accumulated in time series for 24 hours a day and displayed by the result display control means 31.

  According to this embodiment, in addition to the same effects as those of the first embodiment, the harmonic component coincidence degree 18a to 18c for each harmonic abnormality pattern 21a to 21c for each time over a required period of time. Since the change can be displayed, it is possible to grasp the transition of the temporal change of each of the harmonic abnormality patterns 21a to 21c, and to determine that the specific harmonic abnormality pattern 21a to 21c becomes significantly abnormal in any time zone. it can.

(Third Embodiment: Corresponding to Claim 6)
FIG. 21 is a schematic configuration diagram showing a third embodiment of the power quality evaluation system 1 according to the present invention.
In this embodiment, instead of the harmonic component calculation means 11 which is one component of the power quality evaluation system 1, a function of calculating the direction of current included in the quantity of electricity 5 measured by the measuring device 4 (FIG. 22). 11A to which the harmonic component calculation means 11A added is added. Further, in this example, the database 17 stores the harmonic abnormality pattern 21b of the harmonic component 16b that is estimated to be a malfunction of the device or the like and a harmonic abnormality that is a precursor thereof, as shown in FIGS. May be configured to store the harmonic normal pattern 21a, the harmonic abnormal pattern 21b, and the harmonic load pattern 21c.

  Since the other configurations are the same as those in FIGS. 2 to 4, the same functional part is not attached with the subscripts a, b, c, but the data recording means 12, the harmonic component coincidence calculation means 13, The harmonic abnormality estimation means is described as 14. The same applies to the fourth and subsequent embodiments.

  As shown in FIG. 22, the harmonic component calculation unit 11A includes an FFT processing unit 11a and a current direction calculation processing unit 11b. The current direction calculation processing unit 11b determines whether the direction of the harmonic voltage of the kth order (k is a natural number satisfying 2 or more and n or less) which is a harmonic of a certain order and the direction of the harmonic current are the same direction or the reverse direction. The determination is made from the phase difference between the vector and the current vector, and the measured harmonic component calculation result 15 including the current direction is stored in the data recording means 12, for example. Accordingly, as the harmonic abnormality estimation means 14 shown in FIG. 21, for example, the harmonic abnormality estimation result 20 can be output up to the direction of the current from the apparatus or device that becomes the harmonic abnormality generation source, and is displayed on the display device 32. be able to.

FIG. 23 is a diagram for explaining an example of the calculation of the direction (current vector) of the harmonic current performed by the current direction calculation processing unit 11b.
Assuming that a voltage vector 33 of a harmonic voltage of a certain order n and a current vector 34 of a harmonic current of a certain order n, if the delay and advance of the current vector 34 viewed from the voltage vector 33 are within 90 degrees, the current vector 34 is The direction is the same as the voltage vector 33. Conversely, if the delay or advance of the current vector 34 exceeds 90 degrees, the direction of the current vector 34 is opposite to that of the voltage vector 33.

  In the example of FIG. 23, with respect to the voltage vector 33, the current vector 34A and the current vector 34B are in the same direction, and the current vector 34C and the current vector 34D are in the opposite direction.

  Therefore, by adding the current direction calculation processing unit 11b as described above and determining the direction of the harmonic current for each harmonic order, in addition to the effect of the above-described embodiment, the apparatus can be used from the direction of the harmonic current. It is possible to find and display the direction of a device (a harmonic abnormality generating source) that generates a malfunction such as a malfunction or a harmonic abnormality that is a precursor thereof. That is, it can be determined in which direction the abnormality of the harmonic is.

  Therefore, according to this embodiment, the accuracy of the harmonic abnormality estimation result can be further improved as compared with the power quality evaluation system 1 of the first and second embodiments.

(Fourth embodiment: corresponding to claim 7)
FIG. 24 is a schematic configuration diagram showing a fourth embodiment of the power quality evaluation system 1 according to the present invention.

  In this embodiment, the power transmission line 6A from the upper power system to the bus 2 and the power transmission line 6B as a lower power system connected from the bus 2 to the load facility 3B and the lower power line connected from the bus 2 to the load facility 3C. The measuring devices 4A, 4B, and 4C are individually installed on the power transmission line 6C that is the power system, and the electric quantity (voltage, current) 5A from the measuring devices 4A, 4B, and 4C through the transmission systems 7A, 7B, and 7C, respectively. 5B and 5C are incorporated into the power quality evaluation system 1 to evaluate the power quality.

  The power quality evaluation system 1 uses the harmonic component calculation means 11 and 11a of FIGS. 2 to 4, 19 and 21 based on the electric quantities 5A, 5B and 5C measured by the measuring devices 4A, 4B and 4C. For example, the harmonic component of the current flowing through each of the transmission lines 6A, 6B, and 6C is calculated sequentially, and the actually measured harmonic component calculation result 15 is acquired and stored in the data recording means 12. Further, the harmonic component coincidence calculation means 13 calculates a harmonic component coincidence 18b between each actually measured harmonic component calculation result 15 and the harmonic abnormal harmonic component 16b. Then, the harmonic abnormality estimation means 14 calculates the harmonic abnormality estimation results 20A, 20B, and 20C of the currents flowing through the transmission lines 6A, 6B, and 6C based on the harmonic component coincidence degree 18b of each measured harmonic component calculation result 15. Output.

  As a result, the harmonic abnormality estimation means 14 determines the harmonic abnormality estimation result 20A having the direction and the harmonic abnormality pattern 21b that causes the harmonic abnormality flowing in the transmission line 6A, and the harmonic abnormality flowing in the transmission line 6B. Harmonic abnormality estimation result 20B having the same direction as the harmonic abnormality pattern 21b that becomes the factor, and harmonic abnormality estimation result 20C having the direction of the harmonic abnormality pattern 21b that causes the harmonic abnormality flowing in the transmission line 6C are output. it can.

  FIG. 25 shows a harmonic generation source and a harmonic current for explaining a method of identifying a harmonic abnormality generation source from the electric quantities 5A, 5B, and 5C acquired from the measurement devices 4A, 4B, and 4C shown in FIG. It is a figure which shows the relationship.

  For example, assuming that a harmonic abnormality generating source exists in the load facility 3B, for example, the harmonic current 36B passes through the transmission line 6B, the bus 2, and the transmission line 6A under the influence of the harmonic abnormality generation source. Then, it flows into the upper power system, or flows into the load facility 3C through the transmission line 6C.

  At this time, the power quality evaluation system 1 acquires the direction of the harmonic current flowing through each of the transmission lines 6A, 6B, and 6C through the measuring devices 4A, 4B, and 4C as described above. 18, it can be estimated that the harmonic abnormality generating source is the load facility 3 </ b> B based on the direction of the harmonic currents of the transmission line 6 </ b> A, the transmission line 6 </ b> B, and the transmission line 6 </ b> C.

  That is, the harmonic component calculation means 11A of the power quality evaluation system 1 calculates the harmonic component by the FFT processing unit 11a, while the current direction calculation processing unit 11b includes the direction of the harmonic current 36 flowing from the harmonic abnormality generating source. The measured harmonic component calculation result 15 is taken out.

  The harmonic component coincidence calculation means 13 calculates the coincidence between the measured harmonic component calculation result 15 including the direction of the harmonic current 36 and the harmonic abnormal harmonic component 16 b including the direction of the harmonic current 36, and then the harmonic. It passes to the wave abnormality estimation means 14. As a result, the harmonic abnormality estimation means 14 can identify the harmonic pattern 21b that causes the harmonic abnormality with a high degree of coincidence, and therefore identifies the harmonic abnormality generation source having the harmonic pattern 21b that causes the harmonic abnormality. can do.

  For example, when the harmonic pattern 21b that causes the harmonic abnormality of the harmonic current 36B is a failure of the motor with the inverter, the harmonic abnormality generated from the motor with the inverter causes the transmission line 6B, the bus 2, and the transmission line 6A to It can be seen that it flows into the upper power system through, and flows into the load facility 3C through the transmission line 6C.

  Therefore, according to the above embodiment, it becomes a factor of a harmonic abnormality from the direction of each harmonic current 36A, 36B, 36C included in the quantity of electricity measured by a plurality of measuring devices 4A, 4B, 4C. It is possible to easily identify a harmonic abnormality generation source having the harmonic abnormality pattern 21b.

(Fifth embodiment: corresponding to claim 7)
FIG. 26 is a schematic configuration diagram showing a fifth embodiment of the power quality evaluation system 1 according to the present invention.

  The power quality evaluation system 1 is based on the premise that measuring devices 4A to 4C are installed in a plurality of transmission lines 6A to 6C, respectively, as shown in FIGS. As shown in FIG. 27, the harmonic abnormality generation source is specified according to logical condition determination.

  That is, the power quality evaluation system 1 includes harmonic component calculation means 11 and 11A, harmonic component coincidence calculation means 13 and harmonic abnormality estimation means 14, and each of the measurement devices 4A, 4B, and 4C receives the electric quantities 5A and 5B. 5C, the harmonic abnormality estimation source 14 identifies the harmonic abnormality generation source 20 having the harmonic abnormality pattern 21b that becomes the harmonic abnormality factor, and the harmonic abnormality generation source estimation result 37. Output as.

  FIG. 27 is a diagram for explaining the harmonic abnormality generation source determination (specification) logic 38 by the harmonic abnormality estimation means 14.

  The harmonic abnormality generation source determination logic 38 includes a harmonic abnormality generation source determination logic 38A when there is one harmonic abnormality generation source and a harmonic abnormality generation source determination when there are a plurality of harmonic abnormality generation sources. It is divided into logic 38B, and a determination is made based on the determination logics 38A and 38B, and a harmonic abnormality generation source is specified.

  For example, the harmonic abnormality generation source determination logic 38A includes a determination logic that the harmonic abnormality generation source is on the higher power system side, a determination logic that the harmonic abnormality generation source is the load facility 3B, and a harmonic abnormality occurrence. It is divided into determination logic that the source is the load facility 3C, and the conditions are defined respectively.

(Sixth embodiment: corresponding to claim 8)
FIG. 28 is a schematic configuration diagram showing a sixth embodiment of the power quality evaluation system 1 according to the present invention.

  The power quality evaluation system 1 according to this embodiment includes a new alarm generation in addition to the harmonic component calculation means 11 and 11A, the data recording means 12, the harmonic component coincidence calculation means 13 and the harmonic abnormality estimation means 14 and 14A. In this configuration, means 40 is provided.

  The alarm generation means 40 has a harmonic abnormality generation source specified by the harmonic abnormality estimation means 14 and 14A. Among them, the generation degree of harmonics is high, or the so-called generation cause having a high harmonic component coincidence 18b. An alarm 42 indicating that the specified harmonic abnormality source is in a harmonic abnormal state or a specific high frequency is applied to the central monitoring control center 41 that centrally manages the load equipment 3 having the harmonic abnormality generation source and the power energy system. An alarm 42 indicating the abnormal pattern 21b is sent out.

  FIG. 29 is a diagram for explaining an alarm transmission system of the alarm 42 by the alarm generating means 40. FIG.

  The power quality evaluation system 1 connects the alarm transmission systems 43B and 43C for transmitting the alarm 42 between the load facilities 3B and 3C, and similarly connects the alarm transmission system 43D to the central monitoring and control center 41. Connecting. When the alarm generation means 40 is specified as a harmonic abnormality generation source by the harmonic abnormality estimation means 14 and 14A and the degree of the harmonic is large or the harmonic component matching degree 18 is high, the alarm transmission system 43 is set. The alarm 42 indicating the harmonic abnormal state or the alarm 42 indicating the specific high frequency abnormality pattern 21b is notified to the harmonic abnormality generation source that is the cause of the harmonic generation.

In addition, the total distortion rate by Formula (5) is often used for the degree of harmonics.
Total distortion factor = RMS value only for harmonics ÷ RMS value (5)
For example, when the harmonic abnormality generation means is identified by the harmonic abnormality estimation means 14, 14A as the load equipment 3B, the alarm generation means 40 sends the load equipment 3B to the load equipment 3B via the alarm transmission system 43B. Is notified of an alarm 42 indicating that the harmonic is abnormal or a specific high frequency abnormality pattern 21b.

  Further, the alarm generation means 40 notifies the central monitoring control center 41 via the alarm transmission system 43D that the load equipment 3B is in an abnormal state of harmonics or an alarm 42 that the specific high frequency abnormality pattern 21b is present. To be notified.

  When the alarm generating means 40 generates the alarm 42, the alarm 42 may be generated under the conditions shown in FIG. For example, the harmonic warning level threshold value 44 and a certain time (alarm generation time limit value) 45 are set in advance, and the total distortion obtained by the equation (5) exceeds the harmonic warning level threshold value 44, and When the AND condition when a certain time (alarm generation time limit value) 45 has passed is satisfied, an alarm 42 indicating that the load equipment 3B is in a harmonic abnormal state is generated.

  Alternatively, the total distortion rate exceeds the harmonic warning level threshold value 44 and a certain time (alarm generation time limit value) 45 elapses. Further, as shown in FIG. When the AND condition when the extraction threshold value 25 is exceeded is satisfied, the alarm 42 indicating that the load equipment 3B is in a harmonic abnormal state or the alarm 42 having a harmonic abnormal pattern 21b having a high harmonic component matching degree 18 Is generated.

Next, another example of the alarm generation system will be described with reference to FIGS. 29 and 30. FIG.
FIG. 31 is a schematic configuration diagram of the power quality evaluation system 1 in which a control command generation means 46 is newly provided in the configuration shown in FIG. This corresponds to claim 9.

  This power quality evaluation system 1 includes an alarm generation means 40 and a control command generation means 46 on the output side of the harmonic abnormality estimation means 14 and 14A, and the alarm generation means 40 generates an alarm 42 in the manner described above.

  On the other hand, when it is specified that a certain load facility 3 is a harmonic abnormality generation source, the control command generation means 46 sends a control command 47 such as a stop to the load facility 3.

  FIG. 32 is a diagram for explaining the transmission system of the control command 47 by the control command generating means 46.

  In this example, control command transmission systems 48B and 48C are newly connected between the power quality evaluation system 1 and the load facilities 3B and 3C. For example, the harmonic abnormality generation source is generated by the harmonic abnormality estimation means 14 and 14A. When the load facility 3B is identified, the alarm generation means 40 sends an alarm 42 or a high frequency abnormality pattern 21 indicating that the load facility 3B is in a harmonic abnormal state to the load facility 3B via the alarm transmission system 43B. Alarm 42 is generated.

  On the other hand, the control command generation means 46, for example, when the load abnormality 3B is specified as the harmonic abnormality generation source by the harmonic abnormality estimation means 14, 14A, and the degree of the harmonic is large or the harmonic component matching degree 18 is high. The load facility 3 is prevented from becoming abnormal by sending a control command 47 relating to load reduction including stop to the specified load facility 3 via the control command transmission system 48B.

  Further, the alarm generating means 40 indicates that the load equipment 3B is in a harmonic abnormal state and has sent a control command such as a stop to the load equipment 3B to the central monitoring control center 41 via the alarm transmission system 43D. An alarm 42 is generated.

  As a condition for generating the control command 47, a harmonic danger level threshold value 50 and a certain time (control command generation time limit value) 51 are newly set as shown in FIG. When the total distortion exceeds the harmonic warning level threshold value 44, or as shown in FIG. 17, the AND condition that the harmonic component coincidence degree 18 exceeds the harmonic abnormality extraction threshold value 25 is satisfied. When, for example, an alarm 42 is generated in the load equipment 3B in a harmonic abnormal state, the total distortion rate exceeds and exceeds the harmonic danger level threshold value 50 indicating the danger level of harmonics. When the time has passed a certain time (control command generation time limit value) 51, a control command 47 for stopping the operation or reducing the operation output is sent to the load equipment 3B that is in a harmonic abnormal state, for example.

  Therefore, according to the embodiment as described above, the amount of electricity is obtained from a plurality of locations in the lower power system from the upper power system to the customer, and the generation factor and location of the harmonic abnormality that is one of the power quality And an alarm that the harmonic abnormality is at a warning level is generated, so that the on-site monitoring staff can grasp that the power quality is deteriorating and can take necessary measures.

  In addition, the amount of electricity is obtained from multiple locations in the lower power system from the upper power system to the customer, and the cause and location of the harmonic abnormality, which is one of the power quality, is estimated. In such a state, since a control command for suppressing the harmonic abnormality is sent to the source of the harmonic abnormality, a disaster due to the harmonic abnormality can be avoided in advance.

  In addition, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the third and subsequent embodiments, the harmonic abnormality pattern 21b is described as an example, but the same applies to the harmonic normal pattern 21a and the harmonic load pattern 21c. It is.

  DESCRIPTION OF SYMBOLS 1 ... Electric power quality evaluation system, 3 (3B, 3C) ... Load equipment, 4 (4A, 4B, 4C) ... Measuring apparatus, 5 (5A, 5B, 5C) ... Electric quantity, such as a voltage and an electric current, 6A, 6B, 6C: Transmission line, 7A, 7B, 7C ... Transmission system, 11: Harmonic component calculation means, 11a ... FFT processing section, 11b ... Current direction calculation processing section, 12 ... Data recording means, 13 ... Harmonic component coincidence calculation Means, 13a ... Normalization calculation processing unit, 13b ... Consistency calculation processing unit, 14 ... Harmonic abnormality estimation means, 14a ... Concordance rearrangement processing unit, 14b ... Harmonic abnormality extraction unit, 16a ... Harmonic normal harmonics 16b: Harmonic abnormal harmonic component, 16c: Load harmonic component, 17 ... Database, 21a ... Harmonic normal pattern, 21b ... Harmonic abnormal pattern, 21c ... Harmonic load pattern, 31 ... Result display control means, 40 Alarm generating means, 41 ... central monitoring control center, 46 ... control command generation means.

Claims (8)

Harmonic component calculation means for calculating the harmonic component by analyzing the waveform of the electric quantity such as voltage and current supplied from the power system to the load equipment composed of various devices and equipment,
Harmonic normal patterns of a plurality of normal harmonic components in the normal state of devices, equipment, etc. constituting the load equipment, and harmonics that are a failure of the equipment, equipment, etc. constituting the load equipment, and a precursor of the malfunction A database for storing a harmonic abnormality pattern of a plurality of harmonic abnormal harmonic components estimated to be abnormal;
A first harmonic component coincidence between a measured harmonic component calculation result obtained by the harmonic component calculating means and a harmonic normal harmonic component of a plurality of harmonic normal patterns stored in the database, and the measured harmonic A harmonic component coincidence calculating means for calculating a second harmonic component coincidence between a harmonic component calculation result and a harmonic abnormal harmonic component of a plurality of harmonic abnormal patterns stored in the database;
The harmonic normal pattern having a low first harmonic component coincidence of the harmonic normal harmonic components obtained by the harmonic component coincidence calculating means is estimated as a harmonic normal pattern indicating the possibility of harmonic abnormality. In addition, the harmonic abnormal pattern having a high second harmonic component coincidence of the harmonic abnormal harmonic component is estimated as a harmonic abnormal pattern having a high possibility of harmonic abnormality, and is output or displayed respectively. A power quality evaluation system comprising a wave abnormality output means. Harmonic component calculation means for calculating the harmonic component by analyzing the waveform of the electric quantity such as voltage and current supplied from the power system to the load equipment composed of various devices and equipment,
Harmonic normal patterns of a plurality of normal harmonic components in the normal state of devices, equipment, etc. constituting the load equipment, and harmonics that are a failure of the equipment, equipment, etc. constituting the load equipment, and a precursor of the malfunction A harmonic abnormality pattern of a plurality of harmonic abnormal harmonic components estimated to be abnormal, and a harmonic load pattern of a load harmonic component estimated to be unique to a plurality of load equipment connected to the power system. A database to remember,
A first harmonic component coincidence between a measured harmonic component calculation result obtained by the harmonic component calculating means and a harmonic normal harmonic component of a plurality of harmonic normal patterns stored in the database, and the measured harmonic The second harmonic component coincidence between the harmonic component calculation result and the harmonic abnormal harmonic component of the plurality of harmonic abnormal patterns stored in the database, the measured harmonic component calculation result, and the database are stored in the database Harmonic component coincidence calculating means for calculating a third harmonic component coincidence with load harmonic components of a plurality of harmonic load patterns;
The harmonic normal pattern having a low first harmonic component coincidence of the harmonic normal harmonic components obtained by the harmonic component coincidence calculating means is estimated as a harmonic normal pattern indicating the possibility of harmonic abnormality. Further, the harmonic abnormal pattern having a high second harmonic component coincidence of the harmonic abnormal harmonic component is estimated as a harmonic abnormal pattern having a high possibility of harmonic abnormality, and the load harmonic component is further estimated. The harmonic load pattern having a high degree of coincidence of the third harmonic component is estimated as a harmonic load pattern having a high influence of the harmonic due to the load, and is provided with a harmonic abnormal output means for outputting or displaying each. Power quality evaluation system. In the electric power quality evaluation system according to claim 1 or 2 ,
The harmonic abnormal output means, the harmonic normal pattern having the harmonic normal harmonic component, the harmonic abnormal pattern having the harmonic abnormal harmonic component, the harmonic load pattern having the load harmonic component, One or more types of harmonic patterns are displayed in order from a harmonic pattern having a higher harmonic component matching degree to a lower harmonic pattern. In the electric power quality evaluation system according to claim 1 or 2 ,
A result display control unit is provided instead of the harmonic abnormality output unit, and the harmonic component coincidence of the harmonic pattern is calculated at predetermined time intervals, and the calculated harmonic component coincidence and the harmonic are calculated. A power quality evaluation system, wherein a pattern is displayed in a time series over a certain period. In the electric power quality evaluation system according to claim 1 or 2 ,
The harmonic component calculation means has a current direction calculation processing means for calculating the direction of the harmonic current,
This current direction calculation processing means calculates the direction of the harmonic current from the direction of the harmonic voltage and the direction of the harmonic current for each harmonic order, and the apparatus, device, etc. from the calculated direction of the harmonic current Power quality evaluation system, which determines, outputs, and displays the direction of the harmonic abnormality generating source that generates the harmonic abnormality that is a precursor or a precursor to the malfunction. In the electric power quality evaluation system according to claim 5 ,
Measure the amount of electricity such as voltage and current supplied to a plurality of load facilities from a plurality of observation points from the upper power system to the lower power system, and calculate the harmonic current of the plurality of observation points from the measured amount of electricity. A power quality evaluation system characterized by calculating a direction and identifying a position of the specific load facility that is a source of a harmonic abnormality generating a malfunction or a harmonic abnormality that is a precursor of the malfunction. In the electric power quality evaluation system according to claim 6 ,
The distortion rate for each observation point is calculated, and when the distortion rate exceeds a predetermined harmonic warning level threshold value, alert information is sent to the specific load facility that is the harmonic abnormality generation source. An electric power quality evaluation system comprising an alarm generating means. In the power quality evaluation system according to claim 7 ,
The distortion rate for each observation point is calculated, and when the distortion rate exceeds a predetermined harmonic danger level threshold value that is larger than the harmonic warning level threshold value, the harmonic abnormality generation source is specified. A power quality evaluation system comprising a control command generating means for sending a control command for shutting down operation or adjusting output to the load equipment.

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