JP2002168880A - System for measuring electric energy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for measuring an electric energy which (1) is relatively inexpensive, (2) can be set easily, and (3) can measure highly accurately. SOLUTION: An electric energy meter is used. The electric energy meter generates outside the apparatus, infrared pulses RP for accuracy calibration which flicker by a frequency proportional to an electric energy. The infrared pulses RP for accuracy calibration are detected by an infrared sensor 2. The electric energy is calculated on the basis of the number of the infrared pulses per constant time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric energy measuring system.

[0002]

2. Description of the Related Art When a demand control system is constructed or an electric energy is recorded, a signal relating to the electric energy is required. Conventionally, a pulse detector is connected to an electric energy meter and the pulse detector is connected to the electric power meter. The amount of power was measured based on the number of pulses from.

However, such an electric energy measuring system has the following problems. . The need for an expensive pulse detector to detect the pulses generated by the pulse generator in the energy meter makes the entire system expensive. . When installing the pulse detector, it was very troublesome because the electric power company staff had to open the electric energy meter and electrically connect it to the pulse generator in the electric energy meter. . . When no signal is received from the electric power meter of the electric power company, the electric energy is calculated by calculating the signal obtained by using the CT (current converter) and the VT (voltage converter). There is an error with the electric energy of the electric energy meter of the company. In other words, in that sense, it is not possible to measure the power amount with high accuracy by the conventional method.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electric energy measurement system which is relatively inexpensive, can be easily installed, and can perform highly accurate measurement.

[0005]

The electric energy measuring system according to the present invention uses an electric energy meter which emits an infrared pulse for accuracy calibration which blinks at a frequency proportional to the electric energy to the outside of the instrument. An infrared pulse for calibration is detected by an infrared sensor, and the electric energy is measured based on the number of infrared pulses per fixed time.

[0006] Since the electric energy measuring system of the present invention has the above-described configuration, it has the following operations. . Since infrared pulses for accuracy calibration, which are emitted outside the instrument and flicker at a frequency proportional to the amount of electric power, are detected by a non-contact infrared sensor, an expensive pulse detector can be dispensed with. The whole becomes cheaper. . The infrared sensor for accuracy calibration, which is emitted outside the instrument and blinks at a frequency proportional to the amount of power, is detected by a non-contact infrared sensor. Eliminates the need and hassle. . The infrared sensor for accuracy calibration, which is emitted outside the instrument and flashes at a frequency proportional to the amount of power, is detected by an infrared sensor in a non-contact manner, so the amount of power is the same as the power meter's power meter. Can be measured. That is, highly accurate measurement can be performed.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a demand control system to which the present invention is applied employs an energy meter 1 which emits an infrared pulse RP for accuracy calibration blinking at a frequency proportional to the amount of electric power outside the instrument. In order to exhibit the effect of the present invention, the infrared pulse R
P is detected by the infrared sensor 2 and the infrared pulse RP is output to the demand control device 4 via the amplification / frequency divider 3. And the demand control device 4
And the three air conditioners 50, 51 and 52 are connected via an interface (not shown),
U42 is provided with a switch function for ON / OFF control of three air conditioners.

As shown in FIG. 1, the electric energy meter 1 has a transparent glass 10 on the front surface where an infrared pulse RP is emitted, and the infrared pulse RP is emitted outside the instrument through the transparent glass 10. Has become.

The infrared sensor 2 detects the infrared pulse RP as described above, and outputs the same number of pulses as the detected infrared pulse RP to the amplifier / frequency divider 3. Note that a commercially available infrared sensor 2 can be used.

The amplification / frequency divider 3 amplifies the pulse output from the infrared sensor 2 and divides the pulse into a number that can be easily counted. The frequency-divided pulse is supplied to a CPU 42 of a demand control device 4 described later. Is output to

As shown in FIG. 1, the demand control device 4 includes a storage unit 40 incorporating a RAM and the like, a ROM 41 into which a control pattern is input, a CPU 42 corresponding to a control unit for controlling the entire device, and a clock. Device 43 and 10 second timer 44
And an operation display unit 45. And CP
In the demand control of U42, processes such as the following steps 1 to 36 are performed. (Step 1) The CPU 42 initializes the entire apparatus when the power is turned on. (Step 2) Data input by the user is read.

The input data includes the date, time, number of channels, 12 target powers P1 for each month, base power P3 (power values of load equipment other than air conditioners that cannot be cut off at all), control rate θ. (The basic value of load control),
The control start rate S (a numerical value for determining that the control is to be performed if the air conditioner is operating at a set rate or more), the VCT ratio (indicating the combined alteration ratio, and calculating the current power P, which will be described later) 1), control start power SW (a reference value for determining that load control is not performed when the second target power P2 falls below this value, SW = P3
+ (P1−P3) × S), pulse constant (numerical value used in equation (1) for calculating current power P), and load control time t (interruption time of air conditioner load). Can be The input of data is performed via the operation display unit 45.

Here, equation (1) is represented by the following equation: current power P = (number of input pulses up to the present time) × VCT ratio × (2 / pulse constant). (Step 3) After the data is read, the zero point adjustment of the timepiece device 43 is performed, and the timepiece device 43 is started from 0:00.

The zero point adjustment of the clock device 43 is performed by manually setting the clock device 43 so as to coincide with the starting point of, for example, a 30 minute cycle determined by the electric power company, and the clock device 43 is started in response thereto. (Step 4) The CPU 42 transmits a return permission signal to each of the air conditioners 50, 51, 52. Here, the return permission signal is transmitted when the air conditioner that is being controlled from ON to OFF from the previous time limit remains accurate at the initial calculation stage. Are in the non-control state (there is no air conditioner under control at the first time). (Step 5) “1” is set in a register used for processing described later. (Steps 6 to 8) The CPU 42 receives the signal from the amplifier / frequency divider 3, calculates the current power P from the number of input pulses based on the equation (1), and predicts the current power P from the equation (2) described later. The power R is calculated. Then, the obtained predicted power R is set in a register, and from the value, the second target power P2 is calculated as P2 = R
-Rθ, and compares the second target power P2 with a preset target power P1 for the current month.

Here, equation (2) indicates that the predicted power R = P +
(ΔP / Δt) × (30−t) (ΔP: increase in demand during Δt minutes) (Steps 9 to 14) Then, when the second target power P2 exceeds the target power P1, the target power P1 is set as the reference power P0, but when the second target power P2 falls below the target power P1, the second target power P2 is reduced. Further, the second target power P2 is set as the reference power P0 when compared with the control start power SW and is larger than the control start power SW.
If 2 is equal to or less than the control start power SW, the state becomes the non-control state, and the routine proceeds to step 37. That is, a second target power P2 that plays a role of a breakwater is set for the target power P1, and as shown in FIG. 4, the second target power P2 is not changed unless the second target power P2 exceeds the target power P1. When the predicted power R exceeds the reference power P0 (= second target power P2) as the reference power P0, control is performed to set the predicted power R to the reference power P0. Conversely, as shown in FIG. 2 If the target power P2 is equal to or less than the target power P1, the target power P1 is
When the predicted power R exceeds the reference power P0 (= target power P1), control is performed to set the predicted power R to the reference power P0. When the second target power P2 is equal to or less than the control start power SW, the control is set to the non-control state in order to enable fine control according to the actual operating condition of the air conditioner. (Step 15) The target power P1 or the second power
When the target power P2 is set, the clock device 43 waits until 20 seconds have elapsed. (Steps 16 to 19) After the elapse of 20 seconds, the 10-second timer 44 is started, and the following processing is performed until the 10-second timer 44 is over. That is, a signal from the amplifier / divider 3 is received, the current power P is calculated from the number of input pulses based on the equation (1), and the predicted power R is calculated from the equation (2). (Steps 20 to 22) Then, the obtained predicted power R is compared with the set reference power P0, the predicted power R is larger than the reference power P0, and
If the flag F indicating that 27 minutes and 00 seconds have elapsed in 34 is not 1 (F = 0), the demand control in step 23 and thereafter is performed. Alternatively, even if the predicted power R is larger than the reference power P0 and the flag is 1, if the set content of the reference power P0 is the target power P1, the demand control in step 23 and thereafter is performed. (Steps 23 to 27) In the demand control, first, the register M is set in the register n, and the NO. It is determined whether the air conditioner corresponding to n is currently ON. Since M is initially set to 1 in step 5 described above, NO. It is determined whether one air conditioner is ON. N
O. If the air conditioner of No. 1 is OFF, the register n is incremented by one, and NO. It is determined whether the air conditioner No. 2 is ON or not, and the same processing is repeated to set any air conditioner to O
Until N is confirmed, it is determined whether or not the air conditioners of the number of points (three) have been turned on. (Steps 28 to 31) Then, if any of the air conditioners
When it is confirmed that N is set to N (in step 13, the condition that the second target power P2 is larger than the control start power SW is satisfied, and either of the air conditioners is turned on), the register M is set to the register n. Is set to the number incremented by 1, and if this number exceeds the score 3, the original 1 is set to the register M, and the CPU 42 sets the NO. The air conditioner n is forcibly turned off, and a return permission signal automatically turned on after the elapse of the load control time t seconds input in advance is simultaneously transmitted. In this way, one of the air conditioners
As the power is turned off from N, the current power P and the related predicted power R decrease. (Steps 32, 33, 35) Next, the CPU 42 determines whether or not the clock device 43 has passed 3:00 or 27:00 seconds. Unless the clock device 43 has passed 27:00 seconds, the CPU 42 proceeds to step 35. Then, it is determined whether or not the 10-second timer 44 has exceeded. When the 10-second timer 44 is over, the processing of the above-described steps 16 to 20 is repeated, and the predicted power R is larger than the reference power P0 and the flag F
Is not 1, or the predicted power R is equal to the reference power P0.
Even if the flag F is 1, the reference power P0
Is set to the target power P1, the demand control in and after step 23 is performed (steps 21 and 2).
2) Forcibly control an air conditioner that is different from the air conditioner that was previously controlled to be turned off from ON to OFF, and simultaneously transmits a return permission signal that is automatically turned on after a lapse of the load control time t seconds (step). 23-31). Thus, a total of two air conditioners are turned on, including the air conditioner that was turned off last time.
The current power P and the predicted power R associated therewith further decrease as the power is turned off.

That is, it is determined every 10 seconds whether demand control is necessary based on whether the predicted power R is greater than the reference power P0 (steps 20 to 22). , A predetermined control order (N
O. 1 → NO. 2 → NO. 3 → NO. 1), the operating air conditioner is turned off, and a signal for automatically returning the air conditioner after t seconds elapses is transmitted. The next operating air conditioner is operated until the expected power R becomes equal to or less than the reference power P0. Is turned off and a signal for automatic recovery after t seconds elapses. (Step 34) When it is determined in step 33 that the clock device 43 has passed 27:00 seconds, 1 is set in the flag F. Only when the predicted power R is greater than the reference power P0 and the set content of the reference power P0 is the target power P1, the following demand control is performed. In this case, a new control signal is not transmitted as much as possible in order to ensure the accuracy of the initial calculation of the next time period of 30 minutes during the three minutes from 27: 00 to 30: 00 seconds. Therefore, it is preferable that the load control time t is also within 3 minutes.
In addition, even if the predicted power R exceeds the monthly target power P1 just because the clock device 43 has passed 27:00 seconds, the power consumption may exceed the peak value of the annual power consumption if no control is performed. If the second target power P2 is larger than the target power P1, the control target is set. (Step 36) In the step 32, the clock device 43 sets 30 minutes 0.
When it is determined that 0 seconds have elapsed, the clock device 43 resets to 0 again.
Starting from minute 00 seconds, the same processing is performed. In step 13, the second target power P2 is set to the control start power S
If it is less than W, it goes into the non-control state and proceeds to step 37,
When it is determined that the clock device 43 has passed 30 minutes 00 seconds, the clock device 43 is started again at 0 minutes 00 seconds, and the same processing is performed.

As described above, when the expected power R exceeds the reference power P0, the operating air conditioner is automatically turned off to reduce the power, thereby suppressing the peak value of the used power particularly in the summertime to the reference power P0 or less. The power consumption can be suppressed to the reference power P0 or less even in another period, so that the power cost can be reduced comprehensively.

In this embodiment, the second target power P2 is provided as a breakwater for the target power P1, but the target power P1 is used as it is as the reference power P0 every 10 seconds without providing the second target power P2. If the expected power R is larger than the target power P1 as compared with the expected power R, the above-described demand control may be performed. In this case, a new control signal for ensuring the accuracy of the initial calculation of the next time period of 30 minutes is not transmitted as much as possible during the three minutes from 27: 00 to 30: 00 seconds. No processing is performed.

In the above embodiment, when the expected power R is larger than the target power P1, the air conditioner which is the load is
Although the switch is turned off from N, the present invention is not limited to this. The alarm sound or the warning light may be turned on. Then, when the expected power R becomes smaller than the target power P1, the alarm sound or the alarm light is changed from the ON state to the OFF state.

On the other hand, in the above embodiment, the demand control system is configured by applying the present invention. However, the present invention is not limited to this. In other words, using the power measurement system of the present invention, the power required by the user, for example, the instantaneous power, the power for 30 minutes (a certain time such as one hour), the power for one day, and the power for one month CPU to calculate the amount of power
A system for printing out may be configured.

[0022]

The present invention has the following effects since it has the above-described configuration.

As is clear from the description of the latter half of the column of means for solving the problems, it is possible to provide a power amount measuring system which is relatively inexpensive, can be easily installed, and can perform highly accurate measurement. Was.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a demand control system according to an embodiment of the present invention.

FIG. 2 is a flowchart showing processing contents of a CPU constituting the system shown in FIG. 1;

FIG. 3 is a flowchart showing processing contents of a CPU constituting the system shown in FIG. 1;

FIG. 4 is a schematic diagram illustrating a relationship between a target power and a second target power, and illustrates a case where the second target power is equal to or less than the target power.

FIG. 5 is a schematic diagram showing a relationship between a target power and a second target power, and shows a case where the second target power is larger than the target power.

[Explanation of symbols]

 RP Infrared pulse R Predicted power P1 Target power P Current power 1 Energy meter 2 Infrared sensor 3 Amplification / segmentation cycle 4 Demand controller 40 Storage unit 41 ROM 42 CPU 43 Clock unit 44 Timer 45 Operation display unit

Claims (1)

[Claims] An energy meter that emits an infrared pulse for accuracy calibration blinking at a frequency proportional to the amount of electric power outside the instrument is used, and the infrared pulse for accuracy calibration is detected by an infrared sensor and is fixed. An electric energy measuring system, wherein electric energy is measured based on the number of infrared pulses per time.