1. A line loss calculation method is characterized by comprising the following steps: it comprises the following steps:

step 1: calculating the electric quantity of each device

The method comprises the following steps of analyzing the electric quantity of each measuring point device by relating to the line loss of a distribution line, wherein the electric quantity comprises an outgoing line breaker, a line section switch or a tie switch and a distribution transformer;

step 2: line segment equipment formation

The distribution master station searches topological equipment at the front end, the rear end and in each section by using a depth and breadth topology searching algorithm by using a graph model library and the switch state of the distribution master station, makes the quantity, the equipment key and the section power supply circuit, and makes a circuit operation mode change state by connecting the operation state change of the switch;

and step 3: electric quantity data checking

Checking the line running state information generated by the line section equipment in the step 2, when the running state of the section line is 'transfer', calculating the line loss amount and the line loss rate by the power distribution main station, but identifying that the running mode change occurs and not judging the section line loss abnormity,

and 4, step 4: segment line loss calculation

According to the step 2, the number of equipment in each section and the electric quantity data check result in the step 3 are made, and the line loss of the section is calculated according to the following formula

In the formula E_swi,E_swi+mSwitching electric quantity of the front end and the rear end of the section i; e_TTUjThe power is distributed and changed;

j 1,2, n is a configuration number in the section i; m is 1,2, the.

Calculating the line loss rate of each section:

Pct_lossi＝Loss_i/E_swi×100％

and 5: segment line loss anomaly determination

And comparing the line loss rate of each section of the line with a set threshold, and outputting alarm information through an alarm service when the line loss rate exceeds the threshold.

2. The line loss calculation method of claim 1, wherein: the electric quantity at the outgoing line breaker in the step 1 is as follows: the distribution automation main station acquires electric quantity from the electric energy acquisition system or acquires power from the EMS by means of the information exchange bus, and if the distribution main station acquires non-electric quantity, the distribution main station acquires power according to a formula

Calculating to obtain the electric quantity of each phase;

electric quantity at the line section switch and the interconnection switch: FTU built-in line loss modules are installed at the site section switch and the contact switch, the FTU has the functions of automatically calculating and freezing 15-minute electric quantity data, and the power distribution master station can acquire the electric quantity data of the FTU as the electric quantity of the FTU;

electric quantity at distribution and transformation places: and an intelligent fusion terminal is installed on the distribution transformer side, and a distribution main station acquires data of 15-minute frozen electric quantity and daily frozen electric quantity of a distribution transformer part from a low-voltage monitoring system through an information exchange bus to serve as electric quantity of the distribution transformer part.

3. The line loss calculation method of claim 1, wherein: in the direction of the electric quantity in step 1, when the bus flows to the load side, the electric quantity is defined as positive, otherwise, the electric quantity is negative, and when the electric quantity of each device is made, the electric quantity is made as positive or negative.

4. A line loss calculation method according to claim 3, wherein: when the equipment directly collects or obtains 15 minutes of electric quantity from other systems in the step 1, the equipment directly adopts the electric quantity value and the electric quantity direction value; if the electric quantity is obtained through calculation, calculating the electric quantity once every 15 minutes from the point 0 as the electric quantity of the equipment every 15 minutes; and if the collection point is abnormal, marking that the equipment is abnormal in collection, and the electric quantity is 0.

5. The line loss calculation method of claim 1, wherein: and when any abnormal mark of the acquisition point of the equipment exists in the section in the step 3, the section does not carry out line loss calculation, and the abnormal electric quantity in the calculation time of the section is marked.

Background

The line loss theoretical calculation is an important technical means for line loss management and analysis, can accurately know the composition condition of the loss in the power grid through the theoretical calculation, provides a reliable basis for fully exploiting the loss reduction potential of power grid enterprises, and is particularly important in technical and economic comparison of different investment schemes, demonstration of loss reduction effect and the like. The method for calculating the theoretical line loss of the power distribution network mainly comprises a forward-backward power flow method, an equivalent resistance method (a capacity method and an electric quantity method), a root mean square current method, an average current method, a maximum current method and the like. The root mean square current method, the average current method, the maximum current method, the equivalent resistance method and the like require less data information, the calculation method is simple and convenient for computer programming, but the loss reduction analysis is inconvenient due to low calculation precision; the scheme is a lean line loss analysis method based on a distributed power distribution intelligent terminal and a self-adaptive topological algorithm, and line loss of each section of a power distribution line is analyzed in real time by means of a power distribution automation main station graph-model library, real-time topology and real-time information; therefore, it is necessary to provide a line loss calculation method that is fast and convenient in generating the electric quantity of the equipment, analyzes the line loss of each section, and can send out warning information.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a line loss calculation method which is rapid and convenient to make the electric quantity of equipment, analyzes the line loss of each section and can send out alarm information.

The purpose of the invention is realized as follows: a line loss calculation method comprises the following steps:

step 1: calculating the electric quantity of each device

The method comprises the following steps of analyzing the electric quantity of each measuring point device by relating to the line loss of a distribution line, wherein the electric quantity comprises an outgoing line breaker, a line section switch or a tie switch and a distribution transformer;

step 2: line segment equipment formation

The distribution master station searches topological equipment at the front end, the rear end and in each section by using a depth and breadth topology searching algorithm by using a graph model library and the switch state of the distribution master station, makes the quantity, the equipment key and the section power supply circuit, and makes a circuit operation mode change state by connecting the operation state change of the switch;

and step 3: electric quantity data checking

Checking the line running state information generated by the line section equipment in the step 2, when the running state of the section line is 'transfer', calculating the line loss amount and the line loss rate by the power distribution main station, but identifying that the running mode change occurs and not judging the section line loss abnormity,

and 4, step 4: segment line loss calculation

According to the step 2, the number of equipment in each section and the electric quantity data check result in the step 3 are made, and the line loss of the section is calculated according to the following formula

In the formula E_swi,E_swi+mSwitching electric quantity of the front end and the rear end of the section i; e_TTUjThe power is distributed and changed; j 1,2, n is a configuration number in the section i; m is 1,2, the.

Calculating the line loss rate of each section:

Pct_lossi＝Loss_i/E_swi×100％

and 5: segment line loss anomaly determination

And comparing the line loss rate of each section of the line with a set threshold, and outputting alarm information through an alarm service when the line loss rate exceeds the threshold.

Step 1, electric quantity at the outgoing line breaker: the distribution automation main station acquires electric quantity from the electric energy acquisition system or acquires power from the EMS by means of the information exchange bus, and if the distribution main station acquires non-electric quantity, the distribution main station acquires power according to a formula

Calculating to obtain the electric quantity of each phase;

electric quantity at the line section switch and the interconnection switch: FTU built-in line loss modules are installed at the site section switch and the contact switch, the FTU has the functions of automatically calculating and freezing 15-minute electric quantity data, and the power distribution master station can acquire the electric quantity data of the FTU as the electric quantity of the FTU;

electric quantity at distribution and transformation places: and an intelligent fusion terminal is installed on the distribution transformer side, and a distribution main station acquires data of 15-minute frozen electric quantity and daily frozen electric quantity of a distribution transformer part from a low-voltage monitoring system through an information exchange bus to serve as electric quantity of the distribution transformer part.

In the direction of the electric quantity in step 1, when the bus flows to the load side, the electric quantity is defined as positive, otherwise, the electric quantity is negative, and when the electric quantity of each device is made, the electric quantity is made as positive or negative.

When the equipment directly collects or obtains 15 minutes of electric quantity from other systems in the step 1, the equipment directly adopts the electric quantity value and the electric quantity direction value; if the electric quantity is obtained through calculation, calculating the electric quantity once every 15 minutes from the point 0 as the electric quantity of the equipment every 15 minutes; and if the collection point is abnormal, marking that the equipment is abnormal in collection, and the electric quantity is 0.

And 3, when any equipment acquisition point abnormal identifier exists in the section in the step 3, the section does not carry out line loss calculation, and the electric quantity in the calculation time of the section is identified to be abnormal.

The invention has the beneficial effects that: the method comprises the steps of firstly selecting and analyzing equipment related to line loss of a line, including an outgoing line breaker, a line section switch, a tie switch, a distribution transformer line and the like, acquiring electric quantity of each place, then making acquired equipment information into quantity, equipment key and interval power supply (lines) in a real-time topological search mode, making a line operation mode change state through change of an operation state of the tie switch, and then checking the line operation mode change state; the line loss of each section is calculated according to the number of equipment of each section and the checking result, the line loss is judged to be abnormal, if the line loss is abnormal electric quantity data, a line loss abnormal alarm is sent, otherwise, the line loss of the distribution line is displayed, compared with the prior art, the method can effectively rely on a distribution automation main station graph library, real-time topology and real-time information, the data information source is reliable and convenient, and the method is more suitable for the calculation process; the invention has the advantages of rapid and convenient electric quantity making of equipment, line loss analysis aiming at each section and capability of sending out alarm information.

Drawings

FIG. 1 is a flow chart of the steps of the present invention.

FIG. 2 is a schematic view of example 1 of the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

Example 1

As shown in fig. 1, a line loss calculation method includes the following steps:

step 1: calculating the electric quantity of each device

The method comprises the following steps of analyzing the electric quantity of each measuring point device by relating to the line loss of a distribution line, wherein the electric quantity comprises an outgoing line breaker, a line section switch or a tie switch and a distribution transformer;

step 2: line segment equipment formation

The distribution master station searches topological equipment at the front end, the rear end and in each section by using a depth and breadth topology searching algorithm by using a graph model library and the switch state of the distribution master station, makes the quantity, the equipment key and the section power supply circuit, and makes a circuit operation mode change state by connecting the operation state change of the switch; in the normal operation mode, as shown in the section surrounded by the dotted line in fig. 2, the distribution main station creates a program by the section device, and generates device information for calculating the line loss in the section: firstly, section connecting equipment sw12, sw13, sw14, PB7 and PB 8; power supply circuit FCB 1; ③ the running state of the line: and (4) normal. When the interconnection switch is switched from on to off and SW12 is switched to a line power supply mode, the power distribution main station creates a program by the section equipment, and generates equipment information for calculating the line loss of the section: firstly, section connecting equipment sw12, sw13, sw14, PB7 and PB 8; power supply circuit FCB 2; ③ the running state of the line: and (6) transferring.

And step 3: electric quantity data checking

Checking the line running state information generated by the line section equipment in the step 2, when the running state of the section line is 'transfer', calculating the line loss amount and the line loss rate by the power distribution main station, but identifying that the running mode change occurs and not judging the section line loss abnormity,

and 4, step 4: segment line loss calculation

According to the step 2, the number of equipment in each section and the electric quantity data check result in the step 3 are made, and the line loss of the section is calculated according to the following formula

In the formula E_swi,E_swi+mSwitching electric quantity of the front end and the rear end of the section i; e_TTUjThe power is distributed and changed; j 1,2, n is a configuration number in the section i; m is 1,2, the.

Calculating the line loss rate of each section:

Pct_lossi＝Loss_i/E_swi×100％

and 5: segment line loss anomaly determination

And comparing the line loss rate of each section of the line with a set threshold, and outputting alarm information through an alarm service when the line loss rate exceeds the threshold.

The method comprises the steps of firstly selecting and analyzing equipment related to line loss of a line, including an outgoing line breaker, a line section switch, a tie switch, a distribution transformer line and the like, acquiring electric quantity of each place, then making acquired equipment information into quantity, equipment key and interval power supply (lines) in a real-time topological search mode, making a line operation mode change state through change of an operation state of the tie switch, and then checking the line operation mode change state; the line loss of each section is calculated according to the number of equipment of each section and the checking result, the line loss is judged to be abnormal, if the line loss is abnormal electric quantity data, a line loss abnormal alarm is sent, otherwise, the line loss of the distribution line is displayed, compared with the prior art, the method can effectively rely on a distribution automation main station graph library, real-time topology and real-time information, the data information source is reliable and convenient, and the method is more suitable for the calculation process; the invention has the advantages of rapid and convenient electric quantity making of equipment, line loss analysis aiming at each section and capability of sending out alarm information.