JPH04235355A - Measuring method for total power consumption in a plurality of circuits and current synthesizing type current transformer used therefor - Google Patents

Abstract

PURPOSE:To provide a measuring method for the total amount of power consumption in a plurality of circuits and a current synthesizing type current transformer by which the total amount of power consumption is simply measured when electric power loads are dispersed at the inside and outside of rooms and the like, and providing a current synthesizing type current transformer used in this method. CONSTITUTION:Standard current transformers 7a and 7b comprising the same ratio of current transformation are provided for every power circuit 6 and 8 of distributed power loads. The currents detected with the standard current transformers 7a and 7b are synthesized in a current synthesizing type current transformer 9. The synthesized output current and applied voltages on the circuits 6 and 8 are inputted into the input terminals of a watthour meter 2. Thus the total amount of power consumption is measured.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention provides a method for easily measuring the total amount of power consumed in multiple circuits when the power load is distributed indoors and outdoors, and a current synthesis method used therein. Regarding type current transformers.

0002

[Prior Art] When the power load of each tenant is distributed in a building with multiple tenants, the method shown in Figure 3 is to measure the total amount of power consumed by each tenant. Power load circuit 2 branched into indoor and outdoor areas
There is a method of integrating and measuring 1 and 22. In such case,
The power load circuits 21 and 22 are integrated by a power main line 23a, and an earth leakage breaker 24 and a molded case breaker 2 are installed in the middle of this main line 23a.
5. In addition, the power main line 23 from the power receiving and transforming equipment 26
b is a main line 23a between the earth leakage breaker 24 and the molded case breaker 25 via the molded case breaker 25' and the standard current transformer 27.
connected to. Then, based on the detected current of the standard current transformer 27 and the circuit voltage, the total power amount is measured by the integrating wattmeter 28. Another method is to install an integrating wattmeter in each of the branched power load circuits and totalize the measured values.

0003

[Problem to be Solved by the Invention] However, in the former method of integrating power trunk lines, a power line with a thickness approximately corresponding to the integrated capacity is required as the power trunk line to be integrated.
It requires a lot of materials and construction costs, and the wiring is complicated. Furthermore, in the latter method of installing an integrating wattmeter in each power load circuit, it is necessary to total the measured values of each integrating wattmeter, which causes problems such as cumbersome administrative work and increased effort and cost.

The present invention was made to solve these problems, and provides a method for measuring the total power consumption in multiple circuits, which can simplify the wiring structure and keep equipment construction costs low, and a method used therein. The purpose of this invention is to provide a current combining type current transformer.

[0005]

[Means for Solving the Problems] The method of measuring the total power consumption in multiple circuits of the present invention is a method for measuring the total power consumption in a plurality of circuits, in which power circuits with distributed power loads are measured within a power consumption measurement category in which power is supplied from the same transformer. For each, a standard current transformer with the same current transformation ratio is installed, and the detected current detected by each standard current transformer is combined by a current combining type current transformer, and the output current of the current combining type current transformer and the output current to the circuit are combined. The total power consumption of a plurality of circuits is measured by inputting the applied voltage to each input terminal of an integrating wattmeter. A current combining type current transformer used in such a measurement method has a plurality of primary windings insulated and surrounded by the same iron core, and a secondary winding insulated and surrounded by these, and each primary winding is It is preferable that the current to be combined be passed through the terminals of the windings so that a current having a value proportional to the sum of the currents passed through the respective primary windings can be obtained from the secondary winding.

[0006]

[Operation] In the above means, the currents (i1, i11) from each standard current transformer provided in different circuits flow to each primary winding of the current combining type current transformer, and from the secondary winding to each A current proportional to the sum of the currents flowing through the primary winding (i2 = i1
+i11) is obtained. The output current (i2) from this secondary winding is input to the input terminal of the current coil of the integrating wattmeter, and the voltage (V) applied to the circuit is input to the input terminal of the voltage coil of the integrating wattmeter. is input. This integrated wattmeter calculates the proportional value (i2 Vt) of the total amount of power consumed with respect to the consumption time (t), and multiplies this by a proportionality constant (a) to measure the total amount of power consumed (ai2 Vt). do.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method of measuring the total power consumption in a plurality of circuits of the present invention and the current combining type current transformer used therein will be described with reference to FIGS. 1 and 2. This measurement method calculates the power consumption of each tenant (in this example, The total amount of electricity (the number of tenants is 3) can be easily measured with an integrating wattmeter 2 using a current transformer or the like.

[0008] The power main line 3 connected to the power receiving and transforming equipment 1 is
It is connected to each power load circuit 6 on the rooftop via one molded circuit breaker 4a provided on the rooftop and three earth leakage circuit breakers 5a branched from the molded circuit breaker 4. A standard current transformer 7a is attached to the circuit wiring of the power load for each tenant installed on the rooftop, and a current i1 proportional to the load current flowing in each circuit 6 flows from the output terminal of each standard current transformer 7a. It looks like this.

[0009] Also, a power main line 3 connected to the power receiving and transforming equipment 1
is connected to each indoor power load circuit 8 via a molded circuit breaker 4b and a branch circuit breaker 5b provided in each tenant's room. Then, the indoor hardwired circuit breaker 4b and the branch circuit breaker 5
A standard current transformer 7b similar to the one on the rooftop is installed between the current transformer 7b and the current i proportional to the load current flowing through each power load circuit 8.
11 flows from the output terminal of the standard current transformer 7b. Note that the standard current transformers 7a and 7b output currents having the same current transformation ratio and the same phase.

The output terminal of the standard current transformer 7b provided on the indoor side of each tenant is connected to the input terminal of a composite current transformer 9 similarly provided in each tenant's room. Here, as shown in FIG. 2, the composite current transformer 9 has one secondary winding 11 insulated and surrounding the same annular iron core 10.
, and two primary windings 12 that are insulated and surrounded by the secondary winding 11, and connection terminals are provided on these windings 11 and 12. . In addition, each tenant's standard current transformer 7a is connected to each terminal of the primary winding 12.
, 7b are passed separately, and a current (i2 = i1 + i11) proportional to the sum of the currents passing through each primary winding 12 is obtained from the secondary winding 11. It looks like this.

[0011]The secondary winding 1 of the current transformation combination type current transformer 9
The output terminal of the integrated wattmeter 2 is connected to the input terminal of the current coil of the integrated wattmeter 2, and the same voltage as the indoor and outdoor circuit voltage is input to the input terminal of the voltage coil of the integrated wattmeter 2. This integrated power meter calculates the proportional value of the total amount of power consumed relative to the time consumed, and multiplies this calculated value by a proportionality constant.
Total power consumption can be measured.

In addition, the number of turns of the primary winding 12 in the current transformer 9 is n1, and the number of turns of the secondary winding 11 is n2.
, the current flowing through the primary winding 12 is i1, i11, and the current flowing through the secondary winding 11 is i2, then the following relational expression is obtained. n2 /n1 × (i1 + i11) = i2
Here, n2 /n1 is the turns ratio of the coil.

[0013] In this embodiment, the primary winding of the current transformation/synthesis type current transformer is two circuits, but the present invention is not limited to this, and a large number of primary windings may be provided. In such a case, it is advisable to short-circuit the primary windings of unused circuits.

[0014]

[Effects of the Invention] In the method of measuring the total power consumption in multiple circuits of the present invention and the current combining type current transformer used therein, a standard current transformer is provided for each power load circuit, and the weak The detected current is combined with a current combining type current transformer,
This combined current is used to measure the total power consumption with an integrating wattmeter, so there is no need to extend power main lines, etc. through which large amounts of electricity flow, to the installation location of the integrating wattmeter, or use multiple integrating wattmeters. . Therefore, the wiring configuration can be simplified and equipment construction costs can be kept low.
Furthermore, daily management, repairs, etc. can be simplified. In addition, since the total power consumption can be read in one place, it is easy to compile measurement data, which helps save materials for tenant building management, etc.
It is also possible to save labor.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a method for measuring total power consumption in a plurality of circuits according to the present invention.

FIG. 2 is a diagram showing an embodiment of a current combining type current transformer of the present invention.

FIG. 3 is a diagram illustrating a method of measuring total power consumption according to the prior art.

[Explanation of symbols]

2 Integrating power meter 6 Power load circuit 7a Standard current transformer 7b Standard current transformer 8 Power load circuit 9 Current combining type current transformer 11 Secondary winding 12 Primary winding

Claims (2)

[Claims] Claim 1: Within a power consumption measurement category where power is supplied from the same transformer, a standard current transformer with the same current transformation ratio is provided for each power circuit of distributed power loads, and each standard current transformer is The detected current detected by the current transformer is combined by a current combining type current transformer, and the output current of the current combining type current transformer and the voltage applied to the circuit are input to each input terminal of the integrating wattmeter to calculate the total of multiple circuits. A method for measuring total power consumption in multiple circuits, characterized by measuring power consumption. [Claim 2] In a current combining type current transformer used in a method for measuring total power consumption in multiple circuits, a plurality of primary windings are insulated and surrounded by the same iron core, and a plurality of primary windings are insulated and surrounded by the same iron core. A combined current is passed through the terminals of each primary winding, and a current proportional to the sum of the currents passed through each primary winding is obtained from the secondary winding. Current combining type current transformer.