CN104134172A - Method for estimating average level of long-term magnetic field exposure of households - Google Patents

Abstract

The invention relates to a method for estimating the average level of long-term magnetic field exposure of households. The method comprises the steps of (1) monitoring a sample living room for 24 h and drawing a daily load chart of the sample living room; (2) calculating the daily correction factor a and the daily average load X of the day according to the daily load chart; (3) acquiring the annual load chart of an electric power circuit close to the sample living room; (4) calculating the annual correction factor b and the annual average load Y of the month according to the annual load chart. Compared with the prior art, the method has the advantages of being accurate, saving time and the like.

Description

A kind of resident family on average exposes in long-term magnetic field the evaluation method of level to the open air

Technical field

The present invention relates to magnetic field and expose level calculation method to the open air, especially relate to the evaluation method that level is on average exposed in the long-term magnetic field of a kind of resident family to the open air.

Background technology

At present, the public mainly concentrates on the room low frequency magnetic field of contiguous engineering to the concern of project of transmitting and converting electricity health effect problem.

The angle that expose to the open air in long-term magnetic field from room, what people were concerned about is to expose to the open air under environment at the family's downfield far below exposure limit, adult or children family life over a long time in, be subject to the real standard that expose to the open air in magnetic field to have much.And in the evaluation of current electromagnetic environment, real-time magnetic field level or 24 hours magnetic field levels in the just room of monitoring, actual measurement magnetic field value does not directly represent the people's who lives in this room the long-term actual level that exposes to the open air, in fact, room magnetic field levels has significant change in the different time sections of a day or a year, estimate that the long-term magnetic field of resident family exposes the magnetic field levels that level also will be considered room in different time throughout the year to the open air, take China Shanghai as example, winter and summer be air conditioning electricity peak period normally, at this moment room magnetic field levels is will be higher than the room magnetic field levels of spring and fall.

To sum up, obtain the long-term magnetic field of contiguous project of transmitting and converting electricity resident family and on average expose level to the open air, in monitoring real-time magnetic field level, need to utilize certain evaluation method to extrapolate such room annual magnetic field levels, and expose the estimated value of level to the open air using it as the long-term magnetic field of resident family.

Summary of the invention

Object of the present invention be exactly in order to overcome the defect that above-mentioned prior art exists, provide a kind of and save time, evaluation method that accurately resident family on average exposes in long-term magnetic field level to the open air.

Object of the present invention can be achieved through the following technical solutions:

Resident family on average exposes in long-term magnetic field an evaluation method for level to the open air, comprises the following steps:

1) monitoring in 24 hours is carried out in sample room, draw the daily load curve figure in sample room;

2) according to daily load curve figure, calculate day correction factor a and the per day load X of this day;

3) obtain near the yearly load curve figure of the power circuit in sample room;

4) according to yearly load curve figure, calculate the annual load Y of this year.

Described step 2) comprise the following steps:

21) by daily load curve figure, obtain the average daily load X of this day ^*with the period average load of three periods, during 7-15, be X ₁, during 15-23, be X ₂, during 23-7, be X ₃;

22) obtain the correction factor a of each period ₁, a ₂, a ₃,

$a_1=\frac{X_1}{X_{*}},a_2=\frac{X_2}{X_{*}},a_3=\frac{X_3}{X_{*}};$

23) the peak point load in during according to the period 7-15 at peak load place try to achieve per day load X,

$X=\frac{\hat{X}}{a_1}.$

Described step 4) comprise the following steps:

41) according to yearly load curve figure, obtain the monthly average load Y of every month _nwith average annual load Y ^*, obtain the moon correction factor b of every month _n,

$b_n=\frac{Y_n}{Y^{*}}(n=\mathrm{1,2,3}\·\·\·\·\·\·12);$

42) obtain the monthly average value Y in peak value month _max∈ Y _n, and the moon correction factor b of the peak value moon _max, b _max∈ b _n, calculate the annual load Y of this year,

$Y=\frac{Y_{\max }}{b_{\max }}.$

Compared with prior art, the present invention has the following advantages:

1, accuracy is high, has solved annual and has exposed level and the repugnant problem of magnetic field Real-Time Monitoring value to the open air;

2, algorithm is reasonable, has considered the impact of electric load on magnetic field, and estimated value is more reasonable.

Accompanying drawing explanation

Fig. 1 is method flow diagram of the present invention;

Fig. 2 is certain 220kV circuit daily load curve figure.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

Embodiment:

As depicted in figs. 1 and 2, be subject to power transformating and supplying facility to affect near main with the contiguous power circuit use of the per day magnetic field levels in (have power circuit) class room relevant.

One, the day in resident family magnetic field is revised

For being subject to power transformating and supplying facility to affect near the correction of (have power circuit) per day magnetic field levels in class room, adopt the method by the correction of adjacent lines daily load curve.

The specific practice of 24 hours monitoring revised laws of room sample is: mean value and this mean value of 24 hours of per period in statistics daily load curve, obtain the ratio of per period mean value and 24 hourly average values, correction factor as this hour, after finding the concrete monitoring time in certain monitoring room, correction factor with the measured value of this time point divided by this period, just can substantially infer the per day magnetic induction density in this room, for example, the average magnetic induction intensity that records certain room at 10:10 in the morning (loading the higher period) is 0.05 μ T, the correction factor of this period is 1.18, the per day magnetic induction density of inferring this room is 0.05/1.18=0.042 μ T.

For ease of revising, this monitoring was divided into 3 periods according to resident family general activity rule by one day, and 7 of every day o'clock～15 o'clock, 15 o'clock～23 o'clock, 7 o'clock 23 o'clock～next day, each period is 8 hours.

Fig. 2 is the daily load curve of certain 220kV circuit, after having obtained the daily load curve data of the circuit of grade more than many, the same average load of per period on the same day and the ratio of per day load of obtaining, the ratio of some circuit gained is averaged, obtain the correction factor relevant with power circuit load variations.

Table 1 is the day correction factor of having considered electric load.By these correction factors, just can be drawn by the average magnetic induction intensity of certain room particular point in time the per day magnetic induction density in this room.

Table 1 day correction factor

Two, the year in resident family magnetic field is revised

The magnetic field levels of resident family is along with the variation of time changes, and this variation is not only embodied in every day, and institute's measured value is not different in the same time, is embodied in equally the annual not difference of same date institute measured value.Be subject to power transformating and supplying facility to affect near (have power circuit) class room mainly because the load variations of contiguous electric line changes, and not only Yu Zhe family family self electricity consumption situation is relevant.During correction, adopt and day revise a similar method, the yearly load curve according to its contiguous electric line, draws monthly average value and annual mean by yearly load curve, and monthly average value monthly and the ratio of annual mean are the year correction factor of this month.

Claims (3)

1.Yi Zhong resident family on average exposes in long-term magnetic field the evaluation method of level to the open air, it is characterized in that, comprises the following steps:

1) monitoring in 24 hours is carried out in sample room, draw the daily load curve figure in sample room;

2) according to daily load curve figure, calculate day correction factor a and the per day load X of this day;

3) obtain near the yearly load curve figure of the power circuit in sample room;

4) according to yearly load curve figure, calculate the annual load Y of this year.

2. the evaluation method of level is on average exposed in the long-term magnetic field of a kind of resident family according to claim 1 to the open air, it is characterized in that described step 2) comprise the following steps:

21) by daily load curve figure, obtain the average daily load X of this day ^*with the period average load of three periods, during 7-15, be X ₁, during 15-23, be X ₂, during 23-7, be X ₃;

22) obtain the correction factor a of each period ₁, a ₂, a ₃,

$a_1=\frac{X_1}{X_{*}},a_2=\frac{X_2}{X_{*}},a_3=\frac{X_3}{X_{*}};$

23) the peak point load in during according to the period 7-15 at peak load place try to achieve per day load X,

$X=\frac{\hat{X}}{a_1}.$

3. the evaluation method of level is on average exposed in the long-term magnetic field of a kind of resident family according to claim 1 to the open air, it is characterized in that described step 4) comprise the following steps:

41) according to yearly load curve figure, obtain the monthly average load Y of every month _nwith average annual load Y ^*, obtain the moon correction factor b of every month _n,

$b_n=\frac{Y_n}{Y^{*}}(n=\mathrm{1,2,3}\·\·\·\·\·\·12);$

42) obtain the monthly average value Y in peak value month _max∈ Y _n, and the moon correction factor b of the peak value moon _max, b _max∈ b _n, calculate the annual load Y of this year,

$Y=\frac{Y_{\max }}{b_{\max }}.$