JP2005003443A - Electric power reference value calculation method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce costs and labor required for calculating a reference value on electric power. <P>SOLUTION: Values of inverter output from an inverter 3 to a cold water pump 2 are collected at regular intervals to hourly record actual result values (INV data) on the inverter output in a storage part 1-2. Electric energy integration pulses from a watt-hour meter 4 are taken in to record hourly integrated values (electric energy values) on electric energy found based on the integration pulses. When the INV data show that electric energy exceeds 97%, it is determined to express a maximum capacity operation condition. In the event that the INV data show that electric energy exceeds 97% three times successively, hourly electric energy values are extracted between the time when the succession starts and the time when it is interrupted. The extracted energy values are averaged to find hourly average electric energy, which is used as the reference value W<SB>B</SB>on electric power. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power reference value calculation method and apparatus suitable for use in measuring the amount of power reduction.
[0002]
[Prior art]
In recent years, “environmental issues” have been highlighted as social issues, and efforts are being made to reduce environmental impacts from various aspects such as revisions to the Energy Conservation Law and the Recycling Law. Recently, business building (office building) operators have been required to disclose information on efforts to reduce environmental impact.
For this reason, conventionally, various data in a building are automatically collected, and an energy saving result is calculated by a management computer.
[0003]
For example, when the cold water pump and load, determined as the power consumption of the integrated value of power to the load (the actual amount of power is operated at an inverter-controlled variable capacity) P _R, also drove the load at the maximum capacity power per unit required time when (e.g., amount of power per hour) as the reference value W _B of the power, when operated at full capacity by multiplying the operation time to the reference value W _B of the power Determination of the estimated amount of power P _E, so that obtaining the power reduction amount [Delta] P by subtracting the power consumption P _R from the obtained estimated power amount _{P E (ΔP = P E -P} R) ( e.g., Patent documents 1).
[0004]
In weighing the reduction performance of the electric energy, the reference value W _B of the power in advance measurement, is set. For example, the load is actually operated for a long time with the maximum capacity, the power consumption during the operation is measured, the power consumption per hour is obtained from the measurement result of the power consumption, and this is calculated as the power the reference value _{W B.}
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2003-107113
[Problems to be solved by the invention]
However, according to the method of calculating the reference value W _B of the power as described above, for the purpose only to determine the reference value W _B of the power, have created a state of operating at full capacity for a long time continue to load consciously As a result, excessive costs and effort were required.
[0007]
The present invention has been made to solve such problems, and an object of the present invention is to provide a power reference value calculation method and apparatus that can reduce the cost and labor required for calculating the power reference value. There is to do.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, the present invention records a capacity value representing a driving state of a load operated with variable capacity and a power consumption amount every predetermined time, and based on the variable capacity value every predetermined time. Necessary when the load is operated at the maximum capacity based on the extracted power consumption based on the extracted power consumption. The amount of power per unit time is obtained as a power reference value.
For example, the capacity value (variable capacity value) representing the operating state of the load is set to the inverter output value (0 to 100%) every hour to the load, and the state where the inverter output value exceeds 97% is the maximum capacity. The load is in operation. When a state where the load is operated at the maximum capacity occurs continuously for a predetermined number of times (for example, three times), the amount of power consumption for every hour from the start of the continuation to the interruption is extracted. The average power amount per hour is calculated from the consumed power amount, and the average power amount per hour is set as a power reference value (W _B ).
[0009]
Further, the present invention detects a state in which the load is operated at the maximum capacity from the capacity value indicating the operation state of the load operated with the variable capacity as the maximum load state, and the electric energy integration pulse ( Based on the time interval of the pulse generated every time the amount of power supplied to the load reaches a predetermined value), the amount of power per unit time required when the load is operated at the maximum capacity is used as the power reference value. It is what you want.
For example, the capacity value (variable capacity value) representing the operating state of the load is the inverter output value (0 to 100%) to the load, and the load is operated with the maximum capacity when the inverter output value exceeds 97%. (Maximum load state). The maximum load state is detected and based on the time interval of the energy accumulation pulses in the maximum load state T (min), obtaining a reference value W _B of the power. For example, when a power integration pulse is generated each time the amount of power supplied to the load reaches AkWh, the power reference value W _B is obtained as W _B = A · (60 / T) (kW).
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
[Embodiment 1]
FIG. 1 is a block diagram showing a main part of an example of a power reference value calculating apparatus used for implementing the present invention. In the figure, reference numeral 1 denotes a power reference value calculation apparatus according to the present invention, which is realized by hardware including a processor and a storage device, and a program for realizing various functions in cooperation with these hardware. Specifically, a program is installed in a personal computer (personal computer), and is realized as a CPU processing operation according to the installed program.
[0011]
The power reference value calculation device 1 includes a data collection unit 1-1, a storage unit 1-2, and a power reference value calculation unit 1-3. The data collection unit 1-1 periodically collects data on various loads in the building and records the data in the storage unit 1-2. In this example, only the cold water pump 2 is shown as a load in the building for the sake of explanation.
[0012]
The chilled water pump 2 is provided with an inverter (INV) 3 that adjusts the rotational speed of the chilled water pump 2 and a watt-hour meter 4 provided in a power supply path to the chilled water pump 2.
[0013]
The inverter 3 receives an instruction from a host device (not shown), generates an inverter output value (0 to 100%), and adjusts the rotation speed of the cold water pump 2. When the inverter output value is 100%, the rotation speed of the chilled water pump 2 is the maximum value (rated value), and when the inverter output value is 0%, the rotation speed of the chilled water pump 2 is the minimum value (0). Therefore, in this embodiment, the inverter output value can be considered as a capability value (variable capability value) representing the operating state of the chilled water pump 2 that is a load.
[0014]
Each time the watt-hour meter 4 supplies a predetermined amount of power to the load, that is, every time the amount of power supplied to the chilled water pump 2 reaches a predetermined value A (A = 10 kWh in this example), Generate accumulated pulses. More specifically, the wattmeter 4 integrates the power supplied to the load (the power amount per unit time) with the passage of time, and generates a power integration pulse every time the integrated value reaches a predetermined value. After generating the integration pulse, the integration value (measurement value) of the electric energy is reset and the next integration (measurement) is started.
[0015]
In the power reference value calculation device 1, the data collection unit 1-1 collects an inverter output value (instantaneous value) from the inverter 3 to the chilled water pump 2 every hour (in this example, every hour). The inverter output value (INV data) for each hour is recorded in the storage unit 1-2. Further, the power amount integrated pulse from the watt hour meter 4 is taken in, and the integrated value of the power amount per hour (every hour) corresponding to the INV data is set to the number of power amount integrated pulses counted in the past one hour. It is obtained by multiplying by a predetermined value A, and the integrated value (power consumption amount) of the obtained electric energy is recorded in the storage unit 1-2.
[0016]
[Calculation of power of the reference value W _B]
In the power reference value calculation device 1, the power reference value calculation unit 1-3 is based on the hourly INV data and the power consumption amount (hereinafter referred to as the power amount value) recorded in the storage unit 1-2. calculating a reference value _{W B.}
[0017]
FIG. 2A shows a flowchart of a reference value calculation process executed in the power reference value calculation unit 1-3. Before executing the processing of this flowchart, it is assumed that the power reference value calculation unit 1-3 is set with the lower limit value Lmin of the INV data and the lower limit value Nmin of the continuous count as INV data extraction conditions. (Step 101 shown in FIG. 2B). Further, it is assumed that 0 is set as the initial value of the count value N of the continuous number (step 102 shown in FIG. 2B). In the present embodiment, the lower limit value Lmin of INV data is 97%, and the lower limit value Nmin of the number of consecutive times is three.
[0018]
The lower limit value Lmin of the INV data is a threshold value for determining the maximum load state, and the case where the INV data exceeds the lower limit value Lmin is regarded as the maximum load state. Lower limit Nmin consecutive number is a threshold value for the maximum load condition is determined whether the predetermined time or longer, the calculation of the reference value W _B power only when the maximum load state is continuously less than the lower limit Nmin I do.
[0019]
The power reference value calculation unit 1-3 extracts INV data from the storage unit 1-2 according to the flowchart shown in FIG. 2A (step 201). FIG. 3 illustrates the recording status of INV data in the storage unit 1-2. The storage unit 1-2 stores hourly INV data in association with the collected date and time. The power reference value calculation unit 1-3 extracts the INV data in order of date and time from the hourly INV data in the storage unit 1-2.
[0020]
When the power reference value calculation unit 1-3 extracts the INV data (step 201), the power reference value calculation unit 1-3 compares the extracted INV data with a preset lower limit value Lmin of the INV data (step 202). If the extracted INV data does not exceed the lower limit value Lmin (NO in step 202), it is confirmed that the count value has not reached the lower limit value Nmin (NO in step 205), and the secured data is released (step 207). ). Then, the count value N is set to N = 0 (step 208), it is confirmed that the INV data has not ended (NO in step 209), and the process returns to step 201 to extract the next INV data.
[0021]
If the extracted INV data exceeds the lower limit value Lmin (YES in step 202), the count value N is set to N = N + 1 (step 203), and the date and time of the extracted INV data are secured (step 204). After confirming that the INV data has not ended (NO in step 209), the process returns to step 201 to extract the next INV data. This is repeated, and when the extracted INV data falls below the lower limit value Lmin, the count value N is compared with the preset lower limit value Nmin (step 205), and the count value N becomes the lower limit value Nmin. If not reached (NO in step 205), the secured data is released (step 207), the count value N is set to N = 0 (step 208), and it is confirmed that the INV data has not ended (step 209). NO), the process returns to step 201 to extract the next INV data. If the count value N has reached the lower limit value Nmin (YES in step 205), the process proceeds to step 206.
[0022]
For example, in the case of the INV data “May 07, 2001 (Monday)” shown in FIG. 3, the INV data from 1 o'clock to 13 o'clock does not exceed the lower limit Lmin (97%). Therefore, every time INV data is extracted, the secured data is released and the count value N is processed by N = 0, and the next INV data is extracted.
[0023]
The 14:00 INV data exceeds the lower limit Lmin (97%). Therefore, the process proceeds to step 203 in response to YES in step 202, and the count value N is incremented by 1 to N = 1. Further, the date and time of the INV data are secured (step 204), and after confirming that the INV data has not ended (NO in step 209), the process returns to step 201, and the next INV data is the INV at 15:00. Data is extracted.
[0024]
Similarly to the 14:00 INV data, the 15:00 INV data exceeds the lower limit value Lmin (97%), and thus the process proceeds to step 203. In this case, the count value N is incremented by 1 to N = 2, the date and time of the INV data is secured (step 204), and it is confirmed that the INV data has not ended (NO in step 209). Returning to step 201, 16:00 INV data is extracted as the next INV data.
[0025]
It repeats at 16:00, 17:00, and 18:00, and then INV data at 19:00 is extracted (step 208) and compared with the lower limit Lmin of the INV data (step 209). The INV data at 19:00 is 79%, does not exceed the lower limit Lmin (97%), and the continuation of the maximum load state is interrupted. At this time, N = 5.
[0026]
When the count value N reaches the lower limit value Nmin of the number of consecutive times (YES in step 205), the power reference value calculation unit 1-3 stores the same time series power amount value as the date and time of the INV data secured in step 204. Extracted from the unit 1-2 (step 206). In this case, the electric energy values at 14:00, 15:00, 16:00, 17:00, and 18:00 of “May 07, 2001 (Monday)” are extracted from the storage unit 1-2 (step 206). The extracted data is temporarily stored.
[0027]
Then, the secured data is released (step 207), the count value N is set to N = 0 (step 208), it is confirmed that the INV data has not ended (NO in step 209), and the process returns to step 201 and next. INV data is extracted.
[0028]
This is repeated until there is no more INV data.
In this case, the comparison result is YES in step 209, the power reference value calculation unit 1-3 and calculates the reference value W _B of the power using all electric energy values extracted in Step 206 (Step 210 ). For example, if the data period is only “May 07, 2001 (Monday)”, the electric energy values extracted from the storage unit 1-2 at 14:00, 15:00, 16:00, 17:00, and 18:00 (see FIG. 4) ) by averaging the obtains an average power per hour, the average power per this 1 hour with a reference value W _B of the power.
[0029]
In the above-mentioned "the calculation of the power of the reference value _{W B"} is, INV data is "May 07, 2001 (Monday)," it has been described as an example the case only of, "May 08, 2001 (Tuesday) In the INV data, the INV data at 11 o'clock, 12 o'clock, 13 o'clock, and 14 o'clock exceed Lmin continuously for more than Nmin, and the actual power extracted after all the extraction of the data period has ended. the average amount of power per hour is obtained by averaging the amount value, the average power per the 1 hour is the reference value W _B of the power.
[0030]
In this way, the power reference value calculation unit 1-3 determines that the state when the INV data exceeds 97% is the maximum driving state (maximum load state), and the INV data continues three times. If it exceeds 97%, extracting the amount of power value for each hour of until interrupted since the start of the continuous, to calculate the reference value W _B of the power using the power amount value this extraction. By calculating such a way power reference value W _B of, it is not necessary to create a state that is operated at maximum capacity cold water pump 2 continues for a long time to consciously, the calculation of the power reference value W _B The cost and labor required for this can be greatly reduced.
[0031]
In the first embodiment, the hourly INV data and the electric energy value are recorded in the storage unit 1-2. However, the hourly INV data and the electric energy value are not necessarily recorded. May be. For example, INV data and power amount values every 30 minutes may be recorded. In this case, the average electric energy value for each 30 minutes, and the average value calculated average power per hour is doubled, this is a reference value W _B of the power.
[0032]
Further, in the first embodiment, when Nmin = 3 and INV data exceeds 97% for three consecutive times, the electric energy value for every hour from the start of the continuation to the interruption is extracted. but if the INV data exceeds 97% for three consecutive times, immediately extracts the amount of power value for each hour in between, the calculation of the reference value W _B of the power using the power amount value this extracted You may make it perform.
[0033]
Further, in the first embodiment, when the INV data exceeds 97% for three consecutive times, all the hourly power values from the start of the continuation to the interruption are extracted. The one hour electric energy value is not considered highly reliable, and may be excluded for accuracy.
[0034]
[Embodiment 2]
In the first embodiment, the load is the chilled water pump 2, but as shown in FIG. 5, for example, the chilled water pump group 5 including the chilled water pumps 5-1 to 5-n may be used as the load. In the example of FIG. 5, the number control unit 6 controls the number of chilled water pumps 5-1 to 5 -n having the same capacity. In addition, the inverter output of the pump during operation is all controlled with the same value.
[0035]
In this case, the average value of the inverter output of the operating pump is used as the INV data, and the electric energy value is obtained by dividing the power consumption obtained by multiplying the pulse taken from the watt hour meter 4 by the predetermined value A by the number of operating units. By using it, the reference value W _B of power per pump can be obtained.
[0036]
[Embodiment 3]
In the first embodiment, and to calculate the reference value W _B of the power based on the INV data and electric energy values of 1 hour each recorded in the storage unit 1-2, to the cooling pump 2 from the inverter 3 It is also possible to obtain from the inverter output value and the time interval of the electric energy integration pulse from the electric energy meter 4.
[0037]
In this case, as shown in FIG. 6, the power reference value calculation device 7 includes a data collection unit 7-1 and a power reference value calculation unit 7-2. In the power reference value calculation device 7, the data collection unit 7-1 periodically collects inverter output values (variable capacity values) from the inverter 3 to the chilled water pump 2, and collects the inverter output values and threshold values (in this example) Then, 97%) is compared, and the state where the inverter output value exceeds 97% is detected as the maximum load state. In addition, the data collection unit 7-1 takes in the electric energy integration pulse from the watt hour meter 4, and sends the time interval T of the electric energy integration pulse in the maximum load state to the electric power reference value calculation unit 7-2.
[0038]
Power reference value calculation unit 7-2, based on a time interval T of the energy accumulation pulses in the maximum load state transmitted from the data acquisition unit 7-1 obtains the reference value W _B of the power. In this example, the power reference value calculation unit 7-2 is set with a power amount (AkWh / pulse) per pulse of the power amount integration pulse from the watt hour meter 4. Power reference value calculating section 7-2, if the unit time interval T of the electric energy accumulated pulse was divided to obtain the reference value W _B of the power from (1) below (see FIG. 7).
W _B = A · (60 / T) (kW) ··· (1)
[0039]
In the first embodiment, INV data hourly could not determine the three consecutive 97% to unless power reference value W _B of greater than, in the third embodiment, is periodically collected that the inverter output value is in a state that greater than 97% (maximum load condition) can be obtained immediately from its time interval T of the energy accumulation pulses in the maximum load state power reference value W _B.
[0040]
Incidentally, the time interval T of the energy accumulation pulses in the maximum load state is measured a plurality of times, only when the difference time interval T of the plurality of energy accumulation pulse is within the threshold, the power of the reference value W _B of Calculation may be performed.
[0041]
For example, as shown in FIG. 8, the time intervals T1, T2, and T3 of the electric energy integration pulse in the maximum load state are measured, and the difference between T1 and T2 (ΔT ₁₂ ) and the difference between T1 and T3 (ΔT ₁₃ ). , The difference (ΔT ₂₃ ) between T2 and T3 is obtained. If the absolute values of the differences ΔT ₁₂ , ΔT ₁₃ , ΔT ₂₃ are all within the predetermined value α, the time interval T of the electric energy integration pulse is obtained as an average value of T1, T2, T3, and the electric energy integration pulse by substituting the time interval T in the equation (1) obtaining a reference value W _B of the power. Thus, more accurately, it is possible to determine the reference value W _B of the power.
[0042]
【The invention's effect】
As is clear from the above description, according to the present invention, the amount of power consumed when the load is operated at the maximum capacity is extracted from the amount of power consumed every predetermined time based on the variable capacity value every predetermined time. The power reference value is obtained based on the extracted power consumption, and the maximum load state is detected from the variable capacity value, and the power reference is determined based on the time interval of the power amount integration pulse in the maximum load state. By obtaining the value, it is not necessary to consciously create a state in which the load is continuously operated for a long time with the maximum capacity, and the cost and labor required for calculating the reference value of power can be reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram (Embodiment 1) showing a main part of an example of a power reference value calculating apparatus used for carrying out the present invention.
FIG. 2 is a flowchart of a reference value calculation process executed in the power reference value calculation device.
FIG. 3 is a diagram illustrating a recording state of INV data in a storage unit of the power reference value calculation device.
FIG. 4 is a diagram showing an extraction state of a power amount value from a storage unit of the power reference value calculation device.
FIG. 5 is a diagram showing a modification (Embodiment 2) in the case where the cold water pump group is a load in Embodiment 1;
FIG. 6 is a diagram illustrating an example (Embodiment 3) of obtaining a power reference value from an inverter output value and a time interval between electric energy integration pulses.
FIG. 7 is a diagram for explaining a calculation formula for obtaining a power reference value from an inverter output value and a time interval between electric energy integration pulses.
FIG. 8 is a diagram illustrating a method for obtaining a power reference value from a time interval between a plurality of power amount integration pulses in a maximum load state.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electric power reference value calculation apparatus, 1-1 ... Data collection part, 1-2 ... Memory | storage part, 1-3 ... Electric power reference value calculation part, 2 ... Cold water pump, 3 ... Inverter, 4 ... Electricity meter, 5 ... Cold water pump group, 5-1 to 5-n ... cold water pump, 6 ... number control unit, 7 ... power reference value calculation device, 7-1 ... data collection unit.

Claims (6)

A step of recording a capacity value and a power consumption amount representing a driving state of a load operated with a variable capacity every predetermined time;
Extracting the power consumption when the load is operated at the maximum capacity based on the capacity value for each predetermined time from the recorded power consumption for each predetermined time;
A power reference value calculation comprising: calculating a power amount per unit time required when the load is operated at the maximum capacity based on the extracted power consumption amount as a power reference value Method. A step of recording a capacity value and a power consumption amount representing a driving state of a load operated with a variable capacity every predetermined time;
When the capacity value for each predetermined time exceeds a predetermined value continuously for a predetermined number of times, the power consumption for the predetermined time from the start of the continuous operation to the interruption is calculated as the consumption for the recorded predetermined time. Extracting from the electricity,
A power reference value calculation comprising: calculating a power amount per unit time required when the load is operated at the maximum capacity based on the extracted power consumption amount as a power reference value Method. Detecting a state in which the load is operated at the maximum capacity from the capacity value representing the operation state of the load operated with the variable capacity as the maximum load state;
Generating an electric energy integration pulse each time the electric energy supplied to the load reaches a predetermined value;
And a step of obtaining a power amount per unit time required when the load is operated at a maximum capacity based on a time interval of the power amount integration pulse in the maximum load state as a power reference value. A characteristic power reference value calculation method. Means for recording a capacity value and an amount of power consumption representing a driving state of a load operated with a variable capacity every predetermined time;
Means for extracting power consumption when the load is operated at maximum capacity based on the capacity value for each predetermined time from the recorded power consumption for each predetermined time;
A power reference value calculation comprising: means for obtaining, as a power reference value, a power amount per unit time required when the load is operated at the maximum capacity based on the extracted power consumption amount apparatus. Means for recording a capacity value and an amount of power consumption representing a driving state of a load operated with a variable capacity every predetermined time;
When the variable capacity value for each predetermined time continuously exceeds a predetermined value for a predetermined number of times, the power consumption amount for the predetermined time from the start of the continuation to the interruption is calculated for each recorded predetermined time. Means for extracting from the power consumption,
A power reference value calculation comprising: means for obtaining, as a power reference value, a power amount per unit time required when the load is operated at the maximum capacity based on the extracted power consumption amount apparatus. Means for detecting, as a maximum load state, a state in which the load is operated at the maximum capacity from a capacity value representing an operation state of the load operated with a variable capacity;
Means for inputting a power integration pulse generated each time the amount of power supplied to the load reaches a predetermined value;
Means for obtaining, as a power reference value, an amount of electric power per unit time required when the load is operated at the maximum capacity based on a time interval of the electric energy integration pulse in the maximum load state. A power reference value calculation device.

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