KR101307316B1 - Phase of the human body impedance analysis device for electrical equipment - Google Patents

Abstract

PURPOSE: A human body impedance phase analysis device for an electronic device is provided to estimate human body impedance phases based on a human body impedance model, thereby preventing accidents due to electricity. CONSTITUTION: A human body impedance phase analysis device for an electronic device includes a database (100), a human body phase estimation unit (200), and a human body phase analysis unit (300). The database stores human body impedance data based on a human body impedance model. The human body phase estimation unit estimates phases of skin impedance and human body impedance based on the human body impedance data. The human body phase analysis unit computes the phases and the intensity of the human body impedance by using the human body impedance data and human body impedance phase estimation data. The human body phase estimation unit computes skin resistance estimation data (210) and skin capacitance estimation data (220) by using the skin resistance per each contact voltage and human body inner resistance. The human body impedance phase estimation data is computed based on the skin capacitance estimation data. [Reference numerals] (100) Database; (200) Human body phase estimation unit; (210) Skin resistance estimation module; (220) Skin capacitance estimation module; (230) Human body impedance estimation module; (300) Human body phase analysis unit; (310) Phase analysis module; (320) Phase calculation module; (330) Size analysis module; (340) Size calculation module

Description

Phase of the human body impedance analysis device for electrical equipment

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a human body impedance phase analyzer of an electrical device, and more particularly, to a human body impedance phase analysis device of an electrical device for analyzing the human body impedance phase and magnitude.

In the past, a number of applications and publications have been published in addition to Korean Patent Publication No. 2011-0032871, "Earth Leakage Blocking Device."

According to the related art, an earth leakage circuit breaker including a power supply unit for supplying power therein, comprising: an image current transformer (ZCT) for detecting a surge current and a leakage current generated in a distribution line; A control unit which outputs a signal corresponding to the voltage induced in the secondary coil of the image current transformer by the surge current or the leakage current and operates the ground fault interrupting device when an operation signal for operating the ground fault breaking device is received; And a surge protection unit that determines whether a surge current or a leakage current is generated according to the duration of the signal output from the controller, and outputs an operation signal of the ground fault interrupting device to the controller when a leakage current is generated. .

Leakage current can be caused not only by insulation failure in electric equipment and lines, but also by capacitors and stray capacitance of noise filters.

Such leakage current is limited by installing an earth leakage breaker because it may cause an electric shock accident and an accident such as an electric fire in some cases.

In the line filter, a bypass capacitor is installed between the power supply and ground to eliminate power noise.

Through these capacitors, a capacitive current flows from the power supply to ground, and the circuit breaker misinterprets this current as a short circuit.

However, as the digital load increases, the application of the power supply noise removing capacitor is rapidly increasing, and even in the absence of insulation failure, a large capacitive leakage current occurs, causing an unwanted circuit breaker trip.

An object of the present invention has been made in view of the above-mentioned point, the impedance phase of the electrical equipment to estimate and analyze the impedance phase of the human body from the human impedance model and data in order to analyze the effectiveness of leakage current monitoring technology as an electrical disaster prevention technology In providing an analysis device.

The present invention provides a database for storing human body impedance data according to a human body impedance model; A human phase estimator for estimating skin impedance and human body impedance phase from the human body impedance data; And a human body phase analyzer configured to calculate a human body impedance phase and a human body impedance size using the human body impedance data of the database and the human body phase estimation data of the human body phase estimation unit. The skin resistance estimation data for the skin resistance estimation value according to the contact voltage is subtracted by subtracting the internal human body resistance, the skin capacitance estimation data is calculated using the skin resistance and the human body internal resistance for each contact voltage of the skin resistance estimation data. The human body impedance phase estimation data is calculated using the estimated data.

Preferably, the human body impedance model is characterized in that the inside of the human body is a pure resistance (R _i ) component, the input and output contact portions are modeled in parallel configuration of the skin resistance (R _s ) and skin capacitor (C _s ), respectively.

In addition, the human body phase estimating unit preferably reads the human body impedance data from the database, subtracts the 50th percentile human body internal resistance from the 50th percentile DC impedance value for each contact voltage, and estimates the skin resistance according to the contact voltage (V). A skin resistance estimation module for calculating skin resistance estimation data for (Ω); In the human impedance data, the skin resistance and the 50th percentile internal resistance of the skin resistance estimation data of R ₁ and R ₂ are calculated using the 50th percentile human impedance value of 60Hz power supply for each contact voltage. A skin capacitance estimation module for repeatedly calculating the skin reactance value (1 / jωC ₁ ) and calculating the skin capacitance estimation data after substitution into Equation 2); And a human impedance estimation module which calculates human impedance phase estimation data by substituting the skin capacitance estimation data into a skin impedance equation (Equation 3).

&Quot; (2) "

&Quot; (3) "

And preferably, the human body phase analysis unit, phase analysis module for analyzing the correlation between the human body impedance phase estimation data and the contact voltage; A phase calculation module configured to calculate a human impedance phase by using a relational expression between the human body impedance phase estimation data and the contact voltage, which are analysis results of the phase analysis module; A magnitude analysis module analyzing a correlation between the human impedance data and the contact voltage; And a size calculation module configured to calculate a size of the human impedance by using a relationship between the human body impedance data and the contact voltage, the analysis result of the size analysis module.

As described above, according to the present invention, in order to analyze the effectiveness of the leakage current monitoring technology as an electrical disaster prevention technology, the human body impedance phase and magnitude can be analyzed by estimating and analyzing the impedance phase of the human body from the human impedance model and data. It works.

1 is an overall configuration diagram of a human body impedance phase analysis apparatus of an electrical apparatus according to an embodiment of the present invention,
2 is a view showing a human body impedance model of the human body impedance phase analyzer of the electrical apparatus according to an embodiment of the present invention,
Figure 3 is a simplified representation of the human body impedance model of the human body impedance phase analysis apparatus of an electric apparatus according to an embodiment of the present invention,
4 is a diagram of a human body impedance vector diagram of an apparatus for analyzing human body impedance phases according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to exemplary drawings attached hereto.

1 is an overall configuration diagram of an apparatus for analyzing human body impedance of an electric apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a human body impedance model of an apparatus for analyzing human body impedance phase according to an embodiment of the present invention. 3 is a view schematically illustrating a human body impedance model of the human body impedance phase analyzer of the electrical device according to an embodiment of the present invention, and FIG. 4 is a human body impedance phase of the electric device according to an embodiment of the present invention. A diagram relating to the human body impedance vector diagram of the analyzer.

As shown in FIG. 1, the apparatus for analyzing human body impedance of an electric device according to an embodiment of the present invention includes a database 100, a body phase estimator 200, and a body phase analyzer 300.

The database 100 is a configuration in which the human body impedance data according to the human body impedance model is stored.

Here, the human body impedance model may be modeled as a pure resistance (R _i ) components inside the human body as shown in FIG. 2, and the input and output contact portions may have a parallel configuration of skin resistance (R _s ) and skin capacitor (C _s ), respectively. .

At this time, a capacitance component is also present inside the human body, but is generally omitted because it is a small value. In addition, there is a resistance component of the subcutaneous tissue between the skin resistance and the parallel RC circuit of the skin capacitor and the internal resistance of the human body.

The human body impedance model of FIG. 2 is more similar to the actual human body than the model of FIG. 3, but may be simplified and represented as the model of FIG. 3 due to computational complexity.

In FIG. 3, C ₁ and R ₁ values are hand-hand contact models (R ₁ = 2R _s , C ₁ = C _s / 2, R ₂ = R _i ), and two-handed contact models (R ₁ = R _s , C _{1 = C s, R 2 =} R i), hand-depends on the contact model, such as a butt contact model _{(R 1 = R s, C} 1 = C s, R 2 = R i), R 2 value of the human body Resistance value (R _i ) is always the same regardless of contact model.

The skin capacitance value C _s depends on the contact area. The experimental value of skin capacitance per 1 cm ² area is calculated from 0.01 uF / cm ² to 0.05 uF / cm ² using capacitance per unit contact area, where the contact areas are large (82 cm ² ), medium (12.5 cm ² ) and small When (1 cm ² ), the value of skin capacitance C _s is given by the following equation.

[Equation 1]

The total value of the human body impedance depends on the contact voltage, power frequency, contact area, temperature, moisture, and the path of the human body.

Table 1 below summarizes the data of IEC 60479-5 and shows the human impedance value according to the contact voltage in AC 60kV power and DC power. The electric shock condition of Table 1 is for the hand-hand electric shock path when the contact area is large (10,000 cm 2).

[Table 1] (Total human impedance, hand-hand contact model, contact area 10,000cm ² , drying)

If the contact voltage is high, the skin tissue is destroyed and only the internal resistance components appear. The lower the contact voltage, the greater the skin impedance. From Table 1, it can be seen that when the contact voltage is more than 200 V, the human body impedances of the AC 60 mA power supply and the DC power supply have almost no difference. In other words, the effect of skin capacitance is very small.

Therefore, when the human body is in direct contact between the commercial power supply (220 V, 60 kV) and the earth, the human body can be almost interpreted as a resistance component.

Accurately acquiring human impedance and phase data for different contact voltages and other conditions enables simulation of various human electrocution currents.

The human body phase estimator 200 is configured to estimate the skin resistance and the skin capacitance from the human body impedance data and calculate the human body impedance phase based on the human body phase estimation unit 200. The human body phase estimation unit for performing such a function includes a skin resistance estimation module 210, a skin capacitance estimation module 220, and a human body impedance estimation module 230.

In order to estimate the human body impedance phase, the skin resistance estimation module 210 first loads the human body impedance data of the database 100 and subtracts the 50th percentile human body internal resistance from the 50th percentile DC impedance values for each contact voltage in Table 1. The skin resistance estimation data for the skin resistance estimation value (Ω) according to the contact voltage (V) is calculated.

When a DC voltage is applied to the human impedance model of FIG. 3, the skin capacitor may be viewed as an open circuit. Therefore, the value obtained by subtracting the internal resistance of the human body from the DC human impedance value of each contact voltage of Table 1 may be regarded as a skin resistance value.

The skin resistance estimation data calculated by subtracting the 50th percentile human body internal resistance from the 50th percentile DC impedance by contact voltage in Table 1 are shown in Table 2 below.

[Table 2] Estimation of skin resistance (hand-hand contact model, contact area 10,000cm ² , drying)

Similar to estimating skin resistance, skin capacitance can be estimated at commercial frequencies.

Skin capacitance estimation module 220, body-impedance data of the database (Table 1), the 50 percentile, respectively skin resistance estimation data in R ₁ and R ₂ with the body impedance of each contact voltage by 60Hz power (Table 2 Skin resistance and 50th percentile internal resistance of each contact voltage are assigned to the following human impedance equation (Equation 2), and the skin reactance value (1 / jωC ₁ ) is repeatedly calculated to estimate skin capacitance data (Table 3). Calculate

&Quot; (2) "

Table 3 Skin capacitance estimation (hand-hand contact model, contact area 10,000 cm ² , dry)

The values in Tables 2 and 3 do not mean the 50th percentile values of skin resistance and skin reactance, but are intended to determine the characteristics and trends of human impedance by roughly estimating skin impedance.

When the human body impedance estimation module 230 calculates the human body impedance phase by substituting the skin capacitance estimation data of Table 3 into the skin impedance equation (Equation 3), the human body impedance phase estimation data is calculated as shown in Table 4 below.

&Quot; (3) "

[Table 4]

Table 4 shows estimated body impedance phase data (hand-hand contact model, contact area 10,000 cm ² , dry).

From Table 4, it can be seen that the absolute value of the human body impedance phase at the commercial frequency increases as the contact voltage decreases from 175V to 25V.

The human body phase analyzer 300 calculates the human body impedance phase and the human body impedance using the human body impedance data of the database and the human body body phase estimation data of the human body phase estimation unit.

An anatomical phase analysis unit for performing such a function includes a phase analysis module 310, a phase calculation module 320, a size analysis module 330, and a size calculation module 340.

The phase analysis module 310 is configured to analyze the correlation between the human body impedance phase estimation data and the contact voltage.

The phase calculation module 320 calculates the human body impedance phase by using the relational expression between the human body impedance phase estimation data and the contact voltage as the analysis results of the phase analysis module.

The size analysis module 330 is configured to analyze the correlation between the human body impedance data and the contact voltage.

The magnitude calculating module 340 is configured to calculate the magnitude of the human impedance using a relational expression between the human impedance data and the contact voltage, which are the analysis results of the magnitude analysis module.

The body impedance magnitude and the body impedance phase estimation data are summarized using the body impedance 50th percentile value of the body impedance data (Table 1) and the body impedance phase estimate of the body impedance phase estimation data (Table 4) calculated by the body impedance estimation module. Table 5 is as follows.

[Table 5]

Table 5 shows the estimated body impedance and body impedance phase data (hand-hand contact model, contact area 10,000 cm ² , drying).

By performing a 95% confidence level regression analysis using the values in Table 5, we can obtain the relationship between human body impedance phase and contact voltage as shown in (4).

&Quot; (4) "

Comparing the human body impedance phase estimation data of Table 5 with the phase of the human body impedance calculated by Equation 4 is shown in Table 6.

TABLE 6

Table 6 compares the human impedance phase calculated by the relationship between the human body impedance phase and the contact voltage (Equation 4) with the human body impedance phase estimation data.

Since the coefficient of determination is 0.99512 in the regression analysis to obtain Equation 4, it can be seen that the regression equation can explain the relationship between the impedance phase estimate and the contact voltage well.

과

으로 0.05 이하이므로 구해진 Y절편과 기울기계수는 유의한 값이다.
In addition, the Y-intercept and P-value of the gradient machine

and

Since Y is less than 0.05, the obtained Y-intercept and the slope number are significant values.

In Table 6, the relationship between the contact voltage and the magnitude of the human body impedance can be intuitively deduced.

&Quot; (5) "

에 대한 인체 임피던스 크기를 회귀분석하여 결정계수가 가장 큰 a를 구하면 0.27이 된다. a가 0.27로 가정하면 수학식 6과 같은 인체 임피던스의 크기와 접촉전압과의 관계식을 구할 수 있다.While increasing the multiplier a of the contact voltage in Equation 5 from 0.01 to 0.01 unit

The regression analysis of the magnitude of the impedance of the human body for gives the largest crystal coefficient, a, which is 0.27. Assuming that 0.2 is 0.27, a relationship between the magnitude of the human impedance and the contact voltage, as shown in Equation 6, can be obtained.

&Quot; (6) "

Table 7 summarizes the body impedance magnitude calculated by Equation 6. In this regression analysis, the coefficient of determination is 0.99763, so it can be seen that the regression equation of Equation 6 well describes the relationship between the impedance magnitude and the contact voltage.

[Table 7]

과

으로 0.05 이하이기 때문에 구해진 Y절편과 기울기 계수는 유의한 값이다.The P-values of the Y intercept and the slope

and

Since Y is less than 0.05, the obtained Y-intercept and the slope coefficient are significant values.

Using Equation 4 and Equation 6, when the contact voltage is between 25V and 175V, the human body impedance magnitude and phase value can be calculated and the trend can be confirmed. Through this, it is possible to estimate the magnitude and phase of human body conduction current below 175V.

For reference, the human current carrying current phase and the skin impedance are further described as follows.

)는 접촉전압 크기 및 주파수, 전원 용량, 접촉면적, 통전전류경로, 습기, 온도 등에 따라 다를 수 있다. 하지만 통전전류에 영향을 미치는 조건이 고정된 상태에서 접촉전압(

)만 변하는 경우를 가정하면, 인체통전전류는 (수학식7)과 같이 접촉전압을 인체임피던스(

)로 나누어서 계산할 수 있다.Human current carrying current

) May vary depending on contact voltage magnitude and frequency, power supply capacity, contact area, current carrying path, humidity, and temperature. However, the contact voltage (

Assuming that only) changes, the human body conduction current is the human body impedance (

It can be calculated by dividing by).

[Equation 7]

If the phase of the contact voltage is set as the reference phase (0 ㅀ), the phase of the human conduction current has the same magnitude as that of the human impedance and the sign is reversed, as shown in Equations 8 and 9.

[Equation 8]

&Quot; (9) "

Therefore, the phase of the human current carrying current when the human body is electrocuted by directly contacting the commercial power source can be known by obtaining the phase of the human body impedance under the condition. When the human body is electrocuted via leakage path such as resistor, inductor, capacitor, etc., the impedance of the route and the human body impedance should be considered together.

When the human body is electrocuted through the external leakage path, a voltage drop occurs in the leakage path and the voltage applied to the human body decreases. Therefore, the contact voltage acting on the human body is lowered, thereby increasing the skin impedance and the human body impedance.

In FIG. 3, the human body impedance is the same as Equation 10, and Equation 11 is the skin impedance.

&Quot; (10) "

[Equation 11]

4 is a vector diagram of the human body impedance of FIG. 3.

4, since R ₂ has a positive value, the absolute value of the human body impedance phase is smaller than the absolute value of the skin impedance phase.

If the human body impedance is significantly greater than the skin impedance, the phase of the human body impedance is close to zero, on the contrary, if the skin impedance is significantly greater than the human body impedance, the phase of the human body impedance is close to the skin impedance phase.

Looking at the skin impedance of Equation 11, it can be seen that the phase of the skin impedance depends on the jωR ₁ C ₁ term.

As the contact area increases, the skin capacitance increases proportionally and the skin resistance decreases in inverse proportion. Therefore, if the frequency is constant, the product of the skin resistance and the skin capacitance can be regarded as a constant with respect to the contact area. The area and the phase of the skin impedance are independent.

However, the skin impedance phase depends on personal characteristics and other electric shock conditions.

At low voltage levels where skin impedance effects are significant, frequency-dependent measurements show that the skin impedance decreases in magnitude from 130 Hz to 30 Hz as the frequency changes from 1 to 1,000 Hz, and the phase changes from -2 ° to -58 °. Will change to

In addition, as the frequency continues to increase above 1,000 kHz, the skin impedance magnitude continues to decrease and converge to about 1 kHz, a subcutaneous tissue resistance component omitted from modeling in a manner that is added to the internal resistance of the human impedance model.

In the case of phase, as the frequency increases, it decreases from about -60 ° to -80 °, and then grows to converge to 0 Hz.

The frequency at which the skin impedance phase is -45 는 is measured at 4 persons by attaching 2 cm 2 electrodes to the cheeks. The results are 42 ㎐ (male, 20 years old), 48 ㎐ (male, 23 years old), 67 각각 respectively. (Man, 23 years old), 233 ㎐ (female, 4 years old).

For reference, regression analysis is described as an example of a statistical method that can be applied to extract correlations.

Regression analysis is a statistical method for predicting dependent variables when a given independent variable is given by using a linear relationship, which is a mathematical model based on the correlation between independent and dependent variables, for continuous variables observed in statistics. to be. How well the mathematical model obtained as a result of the regression analysis fits the actual population can be measured using the goodness of fit.

The case of analyzing the relationship between one dependent variable and one independent variable is called Simple Regressin Analysis, and the case of trying to identify the relationship between one dependent variable and several independent variables is called multiple regression analysis. Multiple Regression Analysis). As such, regression analysis can be used for statistical prediction of data that changes over time, some effects, hypothetical experiments, and modeling of correlations.

If the dependent variable is y, the independent variable is x, and n is the number of samples, the regression model is given by Equation (12).

[Equation 12]

Y _i = a + βX _i + e _i , I = 1, 2, ..., n

In Equation 12, a represents a regression coefficient and β represents a slope or weight of Xi. In other words, it represents the amount of change in the dependent variable Yi when Xi increases by one unit. ei is an error term and reflects the part not explained by the regression line.

For example, if Xi is the contact voltage and Yi is the human body impedance phase estimation data, the regression coefficient (a) and β (the slope or weight of the contact voltage) are obtained. From then on, the human body impedance phase can be calculated using Equation 12. Can be.

100: database 200: human phase estimation unit
210: skin resistance estimation module 220: skin capacitance estimation module
230: human body impedance estimation module 300: human body phase analysis unit
310: phase analysis module 320: phase calculation module
330: size analysis module 340: size calculation module

Claims (4)

A database storing human impedance data according to a human impedance model;
A human phase estimator for estimating skin impedance and human body impedance phase from the human body impedance data; And
And a human body phase analyzer configured to calculate the human body impedance phase and the human body impedance using the human body impedance data of the database and the human body phase estimation data of the human body phase estimation unit.
The human body phase estimating unit calculates skin resistance estimation data for the skin resistance estimation value according to the contact voltage by subtracting the human body internal resistance from the human body impedance value of the database, and the skin resistance and the human body internal resistance for each contact voltage of the skin resistance estimation data. Computing the skin capacitance estimation data by using, and calculates the human body impedance phase estimation data using the skin capacitance estimation data.
The method of claim 1,
The human impedance model,
Human body impedance phase analysis device of an electric device, characterized in that the internal body is pure resistance (R _i ) components, the input and output contact parts are modeled in parallel configuration of skin resistance (R _s ) and skin capacitor (C _s ), respectively .
The method of claim 1,
The human phase estimation unit,
Importing the human body impedance data from the database, subtracting the 50th percentile human body internal resistance from the 50th percentile DC impedance value by contact voltage among the human body impedance data, and skin resistance to the estimated skin resistance (Ω) according to the contact voltage (V) A skin resistance estimation module for calculating estimated data;
Among the human body impedance data, the skin resistance and the 50th percentile internal resistance of the skin resistance estimation data of R ₁ and R ₂ are respectively calculated using the 50th percentile human impedance value of the 60 Hz power source for each contact voltage. A skin capacitance estimation module for calculating skin capacitance estimation data by repeatedly calculating the skin reactance value (1 / jωC ₁ ) after substitution into Equation 2); And
And a human impedance estimation module for calculating human impedance phase estimation data by substituting the skin capacitance estimation data into a skin impedance equation (Equation 3).
&Quot; (2) "

&Quot; (3) "

The method of claim 1,
The human phase analysis unit,
A phase analysis module analyzing a correlation between the human body impedance phase estimation data and the contact voltage;
A phase calculation module configured to calculate a human impedance phase by using a relational expression between the human body impedance phase estimation data and the contact voltage, which are analysis results of the phase analysis module;
A magnitude analysis module analyzing a correlation between the human impedance data and the contact voltage; And
And a size calculation module for calculating a size of a human impedance by using a relational expression between the human body impedance data and the contact voltage as the analysis result of the size analysis module.

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