JPS5934166A - Measuring device of transformer loss - Google Patents

Abstract

PURPOSE:To reduce a measuring error, by detecting a difference of input/output currents of a transformer by the same current probe, and detecting a difference of input/output voltages of the transformer by the same voltage probe. CONSTITUTION:An output of an oscillator 2 of a loss measuring device 1 supplies power to the primary side of a transformer to be tested 3. Also, the secondary side of the transformer 3 is connected to a load 4. In this state, a current probe 11 detects a difference of an input current and an output current of the transformer 3. Also, a voltage probe 12 detects a difference of input voltage and output voltage of the transformer 3. Outputs of the current probe 11 and a voltage probe 5, and outputs of current probe 10 and the voltage probe 12 are inputted to U-function meters 6, 9, respectively, and each cross power is derived. Subsequently, a transformer loss is derived by the sum of each cross power.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transformer loss measuring device that measures power consumed by a transformer.

Since the loss of a transformer generally appears in the form of heat loss, the power consumption of the transformer can be determined by measuring the total amount of heat generated by the entire transformer.

However, with the above method, there is an error in heat generation measurement, and if the heat consumed by the transformer is small.

I couldn't give a sufficient evaluation.

By the way, in recent years, with the advent of the U-function needle that uses stochastic principle sounds, it has become possible to measure the cross power of two signals with many noise components, and transformer loss can be measured by detecting all voltages and currents and calculating this cross power. This U-function needle made possible by 8 yen rice? Does the measuring device used have the following principle? I was using it. In other words, when calculating the loss of the transformer, the input power request (Put) which is this cross power is calculated from the primary side input voltage and input current of the transformer + the output power in the same way as the secondary side output voltage and output current. (Puz)
', and this difference power is the power consumed by the transformer 1Pt
) was calculated as n. This relationship is shown in equation (1).

Pt:=Put-PIJ2 ・・・・・・・・・
11.1 A conventional transformer loss measuring device of this type (hereinafter referred to as a loss measuring device) will be explained in detail below the 1/1 scale shown in FIG.

In Figure 1, the oscillator (
2) is connected to the negative side of the transformer under test (3) via terminals T1 and Tzk of this loss measuring device (1).
, all power is supplied to the negative side of the transformer (3). The secondary side of this transformer (3) is connected to the terminal T of the loss measuring device 111.
The power transmitted from the secondary side of the transformer (31) is connected to the load (4) via T3 and T4'.
Consume.

(The primary side voltage of the transformer (3) is measured by the voltage detector 51 (hereinafter referred to as voltage globe) and the voltage '(+7) is measured at the terminals Tl and I2 of the loss measuring device fl+, and the output of this voltage globe +51'? It is connected to the -10,000 input terminal of the U-function counter).

(71 measures the total current flowing into the transformer (3) with a T current detector (hereinafter referred to as a current globe), and sends the output of this current probe (7) to the other input terminal of the U function meter (6). Connected.

Also, in (8), the voltage on the secondary side of the transformer (3) is measured using a voltage detector (hereinafter referred to as a voltage probe) using this loss measuring device (1).
All voltages are measured at terminals T3 and I4 of the voltage globe (8), and the output of this voltage globe (8) is connected to the -10,000 input terminal of the U function meter (9).

H measures the current flowing out of the load +41 K from the transformer (3) with a current detector (hereinafter referred to as a current probe), and the output of this current globe 'J[l? Connected to the other input terminal of the U function meter +91. Therefore, the output of the U function meter 161? This power PUI 17 is the primary side input power of the transformer, and the output a′ of the U function meter 191 is the positive pressure globe 8) and the current globe + IQ. Cross power? This power Pu2r becomes the secondary output power of the transformer.

This relationship i is shown in formulas +21 and +31.

Put = EI It ・・・・・・・・・
・−・・・・・・ (2) Puz= E2 Iz
・・・・・・・・・・・・・・・ (3) Here, El is the value of voltage probe (5), If is the value of current probe (7), &f'X voltage globe (8) where h is the value of the current probe αG.

Therefore, the power consumed by the transformer (Pt) is the primary side power minus the entire 2 side power, and is expressed by equation (1). The formula and (3) are as shown in the formula 7141.

Pt = El・If E2 llI2 ------
141 By the way, generally the transformer loss Ptl'm, +
The input/output power of the n;b transformer expressed by Equation 21 and Equation (3) is very small compared to PIJI and PU2.

For this reason, in conventional loss measuring devices of this type, when there is an error factor in the measurement thread (in general, there is always a measurement error), the error component of the input power IPUI), the error component of the output power, and the transformer actually consumed. The loss was at the same level, and there was a drawback that it was not possible to precisely measure the transformer loss sound.

This invention has been made to completely eliminate the shortcomings in the conventional loss measuring device, and to calculate the difference between the input terminal and output current of the transformer measured with one current probe and the difference between the current and voltage measured with the current probe and the output current of the transformer. By calculating the total value of the input voltage of the transformer, the difference voltage between the input voltage and output voltage of the transformer measured with one voltage probe, and the cross power of the output current of the transformer measured with a current probe. The loss of the transformer is calculated using this loss measuring device.

The total measurement error can be made very small and the loss of the transformer can be measured.

Next, an embodiment 'fK of the present invention is shown in FIG. 2 and will be described in detail below. (l is a current globe that detects the difference between the input current flowing into the transformer (3) and the output current flowing from the transformer (3) to the load (4), and 02 is the input voltage of the transformer (3) and the output current flowing from the transformer (3) to the load (4). It is a voltage probe that detects the output voltage difference sound.

The outputs of the current globe u11 and the voltage probe (5) are connected to the inputs of the U function meter (6), and the outputs of the current probe α1 and the voltage probe (12 are connected to the inputs of the U function meter (9)). The connection is fL, and the chromeno of seven points (Wa is looking for all of them/).If we assume that the chromeno of jL is P01 and Pu2, it becomes as shown in equations (5) and (61).

Pu1=Es(It-I2)...
・・・・・・・・・・・・ (5) P(J2２Iz(EtE
z) ・・・・・・・・・・・・・・・ +61 Here &U is the value detected by the voltage probe (5).

tIt is the value detected by the current globe UU at I2).

The value detected by the ht'lXt style probe *(Bt
B2) is the value detected by voltage globe a2. Ri5
If this sum is calculated from Equation 1 and Equation (6), it will be as shown in Equation (7).

P1=Put+Puz=ExIt-EtIz+Iz&
l2E2=&It l4E2...
(7) It can be seen that the result of equation (7) is equivalent to equation (4), and the loss occurring in the transformer can be detected.

In this way, the loss (Pt) k of the transformer according to this invention
Is the loss measurement device you are looking for the difference between the input and output current of the transformer using the same current globe αυ? Detect.

In addition, since the difference sound between the input and output voltage of the transformer is detected using the same voltage globe, it is possible to detect all minute differences in the input/output differential current and input/output differential voltage during measurement.

Moreover, since the mutual interest is taken for measurement, by using this transformer loss measuring device, the measurement error of the transformer loss, which occurs with conventional loss measuring devices of this kind, can be measured to be very small.

Next, what are some specific examples of the effects of this invention? List and explain.

Assuming that the error in the measurement system is 5%, the input voltage (&) is 20cm, the input current (5A), the output voltage (19V), and the output current (
4,5A).

The transformer loss 34 that can be measured with a conventional loss measuring device is (
From equation l), equation (2), and equation (3), PUL = (2
0X 5 ) ±5% Poz "' (19X 4.5 ) ±5% Pt =
Pt+1-P[I2 = 100±5vJt-s5.5
±4.3W= 14.5±9.3W ・・・・・・
(8) Transformer loss (Pt) according to this invention is Pu1= (5-4,5) X20±5
%PUS = (20-19) X4.5±5%Pt
=Put+Puz=IQfO,5VJ+4.5±0
,28vJ=14,5±0.78"...
As is clear from equations (9)+81 and (9), there is a large difference in accuracy between the transformer loss value in the conventional loss measuring device and the transformer loss value according to the present invention. As described above, the transformer loss measurement method according to the present invention has the advantage that the transformer loss measurement error that occurs in conventional loss measurement devices of this type is extremely small and can be measured accurately.

In the embodiment of this invention, the transformer 7 is used as the object to be measured.
Although I have explained using this, it is not limited to this.

The effectiveness of the present invention can also be used to measure the total power loss of other elements, such as Chikok coils, to the extent possible.

[Brief explanation of drawings]

Fig. 1 is a diagram of a conventional transformer loss measuring device, and Fig. 2 is a block diagram of a transformer loss measuring device according to the present invention. is the transformer under test, (4) is the load, (5) is the voltage detector,
16), +91iU function meter, +71, (1(
I and Qll are current detectors, [51, +81 and 0 are voltage detectors, and T1 to T4 are terminals. In Figure 9, parts corresponding to the same warts are indicated by the same symbols. Agent Makoto Kuzuno - Figure 1 Figure 2

Claims (1)

[Claims] A transformer as an object to be measured, an oscillator that supplies all of the power to the transformer, a load that absorbs all of the output power of the transformer, and a first device that detects the current difference sound between the input and output of the transformer.
with a current detector. A first voltage detector that detects the entire input voltage, a first U function needle that connects all n outputs of the first voltage detector and the current detector, and the input and output of the transformer. a second voltage detector that detects the entire voltage difference between the transformer, a second current detector that detects the entire current of the output of the transformer, and a combination of the second current detector and the first voltage detector. A transformer loss measuring device characterized in that it is equipped with a second U function needle to which the output end of the transformer is connected.