JPH02228218A - Power demand monitoring control - Google Patents

Abstract

PURPOSE:To monitor and control power demand effectively and quickly by making power demand prediction by the use of an in-measurement actual demand value and a predicted demand value recursively which is found from a plurality of measurement values obtained by the measurement that was made before that. CONSTITUTION:In case a predicted demand value Rn is found from an actual demand value (measured value) Pn, suppose from a figure indicated here the last measured value Pn-1, the last-tub-one measured value Pn-2, etc., are referred to, the actual demand line 5 is in the increasing tendency. A predicted demand value Rn is found from plural measured values with a straight line found by a recursive technique as a predicted straight line 3. On the basis of a contract demand value S a marginal demand value L and a target demand value Q are set, where the 1st stage alarm is restored when the predicted demand value Rn is not more than the target demand value Q. When the predicted demand value Rn gets in the 2nd stage alarm region and the measured value Pn exceeds a target demand line 4, the 2nd stage alarm is issued. The power demand can thereby be monitored and controlled effectively and quickly.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a power demand monitoring and control method for power receiving and transforming equipment power loads in buildings. [Prior Art] Conventionally, this type of power demand monitoring and control method determines a predicted demand value based on the measured actual demand value at a certain measurement point and the amount of power change obtained from the measured values before that, and then Control was performed by applying and disconnecting loads based on the following. [Division S to be solved! [ii] The conventional power demand monitoring and control method described above makes predictions based on the amount of change in power, and therefore reacts very sensitively to sudden changes in the amount of power. For this reason, the reliability of predicted values for time-series data is low, and when controlling using such predicted values, operations such as unnecessary load application and disconnection occur, making it impossible to perform appropriate control. There is a problem with this. The number of unreleased 11 was taken into account in consideration of the above-mentioned problems.
The object of the present invention is to provide a power demand monitoring and control system that can effectively and quickly monitor and control the power demand. [Means for Solving the Problems] In order to achieve the above object, the present invention provides a demand prediction means for predicting a rate of change in electric energy in a power demand monitoring control method for power receiving and transforming equipment power loads in buildings;
A means for setting a lockout time from the start of monitoring to the start of load application within the demand time, a means for automatically shortening the measurement cycle, and a means for setting an alarm area based on the contract demand value. This configuration includes means for controlling. [Example] An example of the present invention will be described below with reference to the drawings. FIG. 1 is a demand diagram based on a power demand monitoring and control system according to an embodiment of the present invention. This diagram includes a first-stage warning area l, a second-stage warning area 2°, and a predicted straight line 3. Target demand line 4. The actual demand line 5 is shown, the vertical axis 6 is the demand value P (unit: Kw), and the horizontal axis is the time t (unit: minutes).
It is. :Figure 51 shows demand at a certain measurement point to within T.
From the actual demand value (measured value) Po, the predicted demand value R
The purpose is to find n, where Q is the target demand value,
L indicates the limit demand value, and S indicates the contract demand value. At this time, the previous measured value P n-+ and the previous previous measured value P R-2
It can be seen that the actual demand 815 is in the direction of increase (or decrease) M. Therefore, the predicted demand value Rn is determined by using the predicted straight line 3 as a straight line determined by a known regression method from the plurality of measured values described above. In this embodiment, the amount of change is smoothed using smoothing constants α, β, etc., and the coefficient K is determined by the following formula in order to prevent erroneous recognition due to sudden changes. K-(α(Pn-Pn-1)"β(Pn-+-Pn-2
))”...)/A tiHowever, α+β+・Φ・=1 α, β, ・ ・ ・ 〉0 Δ

[Measurement cycle] Here, i = 1 before the lockout time T1゜ck, and i = 2 from the lockout time Tlock to the demand time T.
As, Δtl)Δt2, and has a and K that automatically shortens the measurement period with T1° and k as the boundary. The intersection of the straight line passing through point Pn indicating the actual demand value and the straight line indicating the demand time limit T is defined as the predicted demand value Rn. Also, based on the contract demand value S, set the limit demand value and the target demand value Q. However, SQL>Q), set the range from the target demand value Q to the limit demand value as the first warning area l, and set the limit demand value. The range of the target demand value Q is defined as the second stage warning region 2. When the predicted demand value Rn is less than the target demand value Q, the first stage alarm is restored to 0, and the predicted demand value Rn
enters the second stage alarm region and when the measured value Pn exceeds the target demand line 4, a second stage alarm is generated. Restoration of the second-stage alarm is performed only when the predicted demand value Rn is less than or equal to the target demand value Q and the measured value Pn does not exceed the target demand line 4 before the lockout time limit of the next cycle. The above-mentioned alarm pattern is shown in Fig. 2. In Fig. 2, ■ and ■ indicate the first-stage alarm and second-stage alarm, respectively. Q>Rn), the second stage alarm recovery is only before the next cycle's lock time limit.According to this alarm pattern, the lockout time limit Teach
Power peak cut control is performed during the demand time period 1 (from time 0 to T1ock, only monitoring is performed, no control is performed), and if the tFS-stage alarm is generated, the second stage alarm is also generated at the same time. If so, the load will be disconnected and the load will be re-applied when the first stage alarm is restored. [Effects of the Invention] As explained above, the present invention predicts power demand in a power demand monitoring and control device using a predicted demand value obtained recursively from an actual demand value at the time of measurement and a plurality of previous measurement values. By doing this, more realistic predicted values are used as time-series predictions, and in addition, lockout time and multi-stage alarms are adopted, and wasteful operations such as unnecessary loading and disconnection of loads are eliminated. The advantage is that power demand can be monitored and controlled effectively and quickly.

[Brief explanation of the drawing]

FIG. 1 is a demand diagram of a power demand monitoring and control system according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a monitoring pattern in the example of FIG. 1. l: 1st stage alarm area 2: 2nd stage alarm area 3: Prediction straight line 4: Target demand line 5: Actual demand line 6: Vertical axis showing demand value 7: Horizontal axis showing time T: Demand time limit Tlock: Lock Out time limit tn: Measurement point Pn: Actual demand value Rn: Predicted demand value Q: Target demand value L: Limit demand value S: Contract demand value

Claims (1)

[Claims] In a power demand monitoring and control method for power receiving and transforming equipment power loads in buildings, a demand prediction means for predicting the rate of change in power amount and a lockout time from the start of monitoring within the demand time to the start of load application are set. means and
A power demand monitoring and control system characterized by comprising means for automatically shortening a measurement cycle and means for monitoring and controlling by setting an alarm area based on a contract demand value and using a multi-step alarm.