Collection method for particulate matter detector

1 . A collection method for a particulate matter detector, comprising the following steps:

S1, collecting N groups of initial air particulate matter values according to an initial collection duration t 1 ;

S2, performing normalized calculation on the collected N groups of initial air particulate matter values, to calculate an initial particulate matter variation r 1 among the initial air particulate matter values, and calculating an initial air particulate matter value d 0 according to the initial air particulate matter values;

S3, obtaining a real-time collection cycle coefficient t 2 by performing calculation on the initial particulate matter variation r 1 through a stepwise approximation method and table lookup;

S4, calculating a real-time particulate matter collection interval time t 4 according to the real-time collection cycle coefficient t 2 and a shortest collection interval time t 3 of the particulate matter detector;

S5, collecting an air particulate matter value again after the real-time collection interval time t 4 , where the air particulate matter value collected at this time is a latest air particulate matter value d 1 ;

S6, performing normalized calculation on the latest air particulate matter value d 1 and a data value d 0 displayed by the particulate matter detector, to calculate a real-time particulate matter variation r 2 ;

S7, obtaining a new real-time collection cycle coefficient t 2 by performing calculation on the real-time particulate matter variation r 2 through the stepwise approximation method and table lookup, wherein the latest air particulate matter value d 1 is assigned to the initial air particulate matter value d 0 in this case; and

S8, repeating the steps from S4 to S7.

2 . The collection method for a particulate matter detector according to claim 1 , wherein in S2, when N is an even number, the initial particulate matter variation r 1 is calculated using the following formula,

r

1

=

❘

"\[LeftBracketingBar]"

a

1

-

a

2

a

1

❘

"\[RightBracketingBar]"

in the formula, a 1 is an average value of the first N/2 groups of initial air particulate matter value data, and a 2 is an average value of the last N/2 groups of initial air particulate matter value data.

3 . The collection method for a particulate matter detector according to claim 1 , wherein in S2, when N is an odd number, a first piece of data in the N groups of data is discarded, M groups of data is left, and the initial particulate matter variation r 1 is calculated using the following formula,

r

1

=

❘

"\[LeftBracketingBar]"

a

3

-

a

4

a

3

❘

"\[RightBracketingBar]"

in the formula, a 3 is an average value of the first M/2 groups of initial air particulate matter value data, and a 4 is an average value of the last M/2 groups of initial air particulate matter value data.

4 . The collection method for a particulate matter detector according to claim 1 , wherein a specific method of the stepwise approximation method and table lookup in S3 and S7 is: defining the initial particulate matter variation r 1 or the real-time particulate matter variation r 2 as a variation r, setting a table, and dividing the variation r in the table into several variation segments b from 0 to 1, wherein each variation segment b has a different value range; each variation segment b is provided with a corresponding collection cycle segment c, and each collection cycle segment c also has a different value range; and a calculation formula using the stepwise approximation method is:

t

2

=

t

hi

-

t

lo

r

hi

-

r

lo

⁢

(

r

-

r

lo

)

+

t

lo

in the formula, r hi represents a maximum value of each variation segment b in the variation segment b in which the variation r is located, r lo represents a minimum value of each variation segment b in the variation segments b in which the variation r is located, t hi represents a maximum value in each collection cycle segment c, and t lo represents a minimum value in each collection cycle segments c.

5 . The collection method for a particulate matter detector according to claim 4 , wherein the variation r is evenly divided into several variation segments b from 0 to 1, and a difference between r hi and r lo in each variation segment b is less than or equal to 0.1.

6 . The collection method for a particulate matter detector according to claim 4 , wherein the variation r is divided into 10 variation segments b.

7 . The collection method for a particulate matter detector according to claim 1 , wherein in S6, a calculation formula of the real-time particulate matter variation r 2 is:

r

2

=

❘

"\[LeftBracketingBar]"

d

1

-

d

0

d

0

❘

"\[RightBracketingBar]"

in the formula, when the real-time particulate matter variation r 2 obtained through calculation is greater than 1, the real-time particulate matter variation r 2 is 1.

8 . The collection method for a particulate matter detector according to claim 1 , wherein in S4, a calculation formula of the real-time particulate matter collection interval time t 4 is

t

4

=

t

3

t

2

.

9 . The collection method for a particulate matter detector according to claim 8 , wherein the shortest collection interval time t 3 of the particulate matter detector is greater than or equal to 1.5 seconds.

10 . The collection method for a particulate matter detector according to claim 1 , wherein the initial collection duration t 1 is 10 seconds.