A method and system for online monitoring of occupational exposure level of power frequency electric field in a substation

Abstract

The application discloses a kind of substation power frequency electric field occupational exposure level online monitoring method and system, belong to occupational hazards occupational exposure level monitoring technical field including following steps: according to substation voltage grade and typical design, main transformer area online monitoring point position control, AIS distribution area online monitoring point position control, HGIS distribution area online monitoring point position control, reactive power compensation area online monitoring point position control;In the substation or its accessory facilities ontology setting monitoring terminal, monitoring terminal every interval 30 seconds record output 1 30 seconds within the maximum measurement value;Data continuous monitoring;According to the method of the application, the data monitored are calculated, to obtain the 8-hour occupational exposure power frequency electromagnetic field level of workers, to monitor whether the occupational exposure level of workers meets the requirements of national occupational exposure limit value.This application can realize minimum optimal monitoring point position control, most reasonable and scientific data acquisition and presentation, etc., to realize the daily monitoring of substation power frequency electric field.

Description

Technical Field

[0001] This invention relates to an online monitoring method and system for occupational exposure levels of power frequency electric fields in substations, belonging to the technical field of occupational exposure level monitoring of occupational hazard factors. Background Technology

[0002] A substation is a power facility in a power system that transforms voltage, receives and distributes electrical energy, controls the flow of power, and adjusts voltage. It connects power grids of various voltage levels through its transformers. Electrical energy enters the substation via transmission lines, then passes through distribution equipment to the transformer, where it undergoes voltage transformation before being output through distribution equipment of other voltage levels.

[0003] Transformers in substations and overhead lines are major sources of power frequency electric field hazards. Power frequency electric fields are listed in the "Occupational Hazard Factor Catalogue," and according to national laws and regulations such as the Occupational Disease Prevention and Control Law, workplaces that generate or contain occupational hazards must undergo routine monitoring and periodic commissioned testing. Currently, substation operation and maintenance units mainly entrust third-party technical service agencies to conduct manual periodic testing, typically once every three years, with each test lasting about one to two days. Under these circumstances, the timeliness, continuity, dynamism, and sufficiency of the occupational hazard exposure level data obtained from substations are far from meeting the requirements of routine monitoring mandated by laws and regulations.

[0004] Occupational hazard exposure level is a term in the field of occupational health technology, generally referring to the exposure level of workers within an 8-hour workday or 40-hour workweek, depending on the worker's position and work schedule. In the context of substation workplaces, substation operation and maintenance positions are the main exposure positions to power frequency electric fields, and it is generally necessary to calculate the time-weighted average exposure level for this position over an 8-hour workday. The general approach to obtaining the 8-hour time-weighted average exposure level is as follows: first, obtain power frequency electric field monitoring values ​​of different locations and intensities at appropriate times; then, build a data model; and finally, calculate the 8-hour time-weighted average exposure level based on the data model.

[0005] When it comes to substations, the number of inspection points varies greatly depending on the voltage level and equipment layout, ranging from dozens to thousands. In this situation, relying on manual inspection of each point using existing technology is not only extremely labor-intensive, but also suffers from poor representativeness and repeatability due to the constantly changing nature of operating conditions and the inability to accurately reflect the actual conditions. Firstly, from a scientific perspective, not every inspection point in a substation needs to be checked; selection is necessary. Secondly, minimizing the number of monitoring points after selection is crucial. Thirdly, once the minimum number of monitoring points is determined, the acquired monitoring data needs to be processed, i.e., a data calculation model needs to be built. The principle of calculating the 8-hour time-weighted average contact level of the power frequency electric field is based on the energy weighting method. While the principle itself is not complex, the challenge lies in using data from a minimum number of monitoring points to reflect the monitoring data from thousands of inspection points. Current literature does not elaborate on this aspect.

[0006] In summary, the proposed method and system for online monitoring of occupational exposure levels in substation power frequency electric fields is essential, advanced, and capable of enabling daily monitoring of substation power frequency electric fields. Summary of the Invention

[0007] The purpose of this invention is to provide an online monitoring method and system for occupational exposure levels in power frequency electric fields of substations, which can achieve the minimum and optimal deployment of monitoring points and the most reasonable and scientific data acquisition and presentation.

[0008] A method for online monitoring of occupational exposure levels in power frequency electric fields of substations includes the following steps:

[0009] Step 1: Based on the substation voltage level and typical design content, deploy online monitoring points in the main transformer area, AIS distribution area, HGIS distribution area, and reactive power compensation area.

[0010] Step 2: Install a monitoring terminal at the substation or its auxiliary facilities. The monitoring terminal records and outputs the maximum measurement value within 30 seconds every 30 seconds. Data is continuously monitored and transmitted to the control host.

[0011] Step 3: Calculate the monitored data according to the method of the present invention to obtain the worker's 8-hour occupational exposure level to power frequency electromagnetic field, in order to monitor and determine whether the worker's occupational exposure level meets the requirements of the national occupational exposure limit.

[0012] Preferably, the calculation of the worker's 8-hour occupational exposure to power frequency electromagnetic fields is as follows:

[0013] Step 3-1: Calculate the actual occupational exposure level for an 8-hour workday;

[0014] Calculate the source value L for each of the main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area, and denote it as L. 主变区 L 高抗区 L 配电装置区 L 无功补偿区 ;

[0015] L=

[0016] In the formula: n represents the total number of measurements taken in each area within 8 hours, L i Represents the measured values ​​at each measuring point in each region;

[0017] According to the obtained L 主变区 L 高抗区 L 配电装置区 L 无功补偿区 Calculate the actual level of occupational exposure (L) for 8 hours 8h ;

[0018] L 8h =

[0019] In the formula: t is the actual contact time of each area in an 8-hour work shift;

[0020] Step 3-2, adjust the actual level of occupational exposure (L) for 8 hours. 8h If the occupational exposure limit is not exceeded, the requirements are met; if the occupational exposure limit is exceeded, the requirements are not met, and control and protective measures should be taken.

[0021] Preferably, the method for calculating the level of occupational exposure to power frequency electromagnetic fields during an 8-hour workday can also predict the level by judging the real-time occupational exposure during the 8-hour workday; the specific steps are as follows:

[0022] Calculate the source value L for each of the following areas within a 30-second time period: main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area. 30s , to obtain L 主变区30s L 高抗区30s L 配电装置区30s L 无功补偿区30s ;

[0023] L 30s =

[0024] In the formula: m represents the number of measuring points in each area, Represents the measured values ​​at each measuring point in each region;

[0025] According to the obtained L 主变区30s L 高抗区30s L配电装置区30s L 无功补偿区30s Calculate the 8-hour occupational exposure prediction level L 8h预测 ;

[0026] L 8h预测 =

[0027] Where: n 主变区 This represents the number of main transformers; in a three-phase configuration, one phase equals one transformer. 主变区 n represents the number of measuring points on the main transformer. 高抗区 Represents the number of high-resistance units; one phase equals one unit; k 高抗区 n represents the number of high-resistance testing points; 配电区 k represents the number of loops; 配电区 n represents 4 times the number of measurement points in the power distribution area. 无功补偿区 k represents the number of capacitor or reactor groups. 无功补偿区 This represents the number of measuring points in the reactive power compensation zone;

[0028] 8-hour occupational exposure prediction level L 8h预测 If the exposure level is within the occupational exposure limit, it is considered compliant; if it exceeds the occupational exposure limit, it indicates that the exposure level is too high during this period. In such cases, a warning will be issued and targeted control and protection measures will be taken.

[0029] Preferably, the deployment method of the online monitoring points in the main transformer area is as follows:

[0030] The online monitoring points for the 110kV main transformer area include one point on the incoming line side of the transformer body and one point on the outgoing line side of the transformer body.

[0031] The online monitoring points for the 220kV / 330kV main transformer area include: one point on the incoming line side of the transformer body; one point on the outgoing line side of the transformer body; one point on each side of the transformer body; one point on the transformer surge arrester; and one point on the transformer voltage transformer.

[0032] The online monitoring points for the 500 / 750 / 1000kV main transformer area include: 1 point on the incoming line side of the transformer body; 1 point on the outgoing line side of the transformer body; 1 point on each side of the transformer body; 1 point on the transformer surge arrester; 1 point on the transformer voltage transformer; 1 point on the transformer neutral point reactor; and 1 point on the transformer neutral point voltage transformer.

[0033] Preferably, the AIS distribution area online monitoring points include 1 point for line surge arresters; 1 point for line disconnectors; 1 point for line switches; and 1 point for line current transformers.

[0034] Preferably, the HGIS distribution area online monitoring points include 1 point for line surge arresters; 1 point for line disconnectors; 1 point for line switches; and 1 point for line current transformers.

[0035] Preferably, the online monitoring points in the reactive power compensation area include: one point at the head of the 10kV / 35kV / 66kV overhead bus; one point in the middle of the 10kV / 35kV / 66kV overhead bus; one point at the tail of the 10kV / 35kV / 66kV overhead bus; one point for the 10kV / 35kV / 66kV capacitor; and one point for the 10kV / 35kV / 66kV reactor.

[0036] Preferably, the monitoring terminal is 1.5m above the ground being inspected.

[0037] An online monitoring system for occupational exposure levels of power frequency electric fields in substations, including

[0038] A power frequency electric field monitoring terminal device, responding to a 50Hz three-phase sensor; a memory, a processor, and a computer program stored in the memory and capable of running on the processor, processing the core algorithm of the system.

[0039] The advantages of this invention are: it achieves the minimum and optimal deployment of monitoring points, and the most reasonable and scientific data acquisition and presentation, enabling daily monitoring of the power frequency electric field in substations. Attached Figure Description

[0040] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0041] Figure 1 This is a schematic diagram of the process structure of the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example 1

[0044] This invention provides an online monitoring method and system for occupational exposure levels in power frequency electric fields of substations, comprising:

[0045] 110kV Main Transformer Area Online Monitoring Point Deployment Method

[0046] Measurement point 1: One point on the incoming line side of the transformer body;

[0047] Measurement point 2: One point on the outgoing side of the transformer body;

[0048] 220kV / 330kV Main Transformer Area Online Monitoring Point Deployment Method

[0049] Measurement point 1: One point on the incoming line side of the transformer body;

[0050] Measurement point 2: One point on the outgoing side of the transformer body;

[0051] Measurement point 3: One point on each side of the transformer body.

[0052] Measurement point 4: Transformer surge arrester, 1 point.

[0053] Measurement point 5: Transformer voltage transformer, 1 point.

[0054] 500 / 750 / 1000kV Main Transformer Area Online Monitoring Point Deployment Method

[0055] Measurement point 1: One point on the incoming line side of the transformer body;

[0056] Measurement point 2: One point on the outgoing side of the transformer body;

[0057] Measurement point 3: One point on each side of the transformer body.

[0058] Measurement point 4: Transformer surge arrester, 1 point.

[0059] Measurement point 5: Transformer voltage transformer, 1 point.

[0060] Measurement point 6: Neutral point reactor of transformer, 1 point.

[0061] Measurement point 7: Voltage transformer at the neutral point of the transformer, 1 point.

[0062] 110 / 220 / 330 / 750 / 1000kVA I / O Distribution Area Online Monitoring Point Deployment Method

[0063] Test point 1: Line surge arrester, 1 point.

[0064] Measurement point 2: Line disconnect switch, 1 point.

[0065] Test point 3: Circuit switch, 1 point.

[0066] Measurement point 4: Line current transformer, 1 point.

[0067] Method for Deploying Online Monitoring Points in 110 / 220 / 330 / 750 / 1000kV HGIS Substations

[0068] Test point 1: Line surge arrester, 1 point.

[0069] Measurement point 2: Line disconnect switch, 1 point.

[0070] Test point 3: Circuit switch, 1 point.

[0071] Measurement point 4: Line current transformer, 1 point.

[0072] Method for Deploying Online Monitoring Points in Reactive Power Compensation Zones

[0073] Measurement point 1: Head of 10kV / 35kV / 66kV overhead busbar, 1 point.

[0074] Measurement point 2: 1 point in the middle of the 10kV / 35kV / 66kV overhead busbar.

[0075] Measurement point 3: 1 point at the tail end of the 10kV / 35kV / 66kV overhead busbar.

[0076] Measurement point 4: 10kV / 35kV / 66kV capacitors, 1 point.

[0077] Measurement point 5: 10kV / 35kV / 66kV reactors, 1 point.

[0078] The deployment method is selected based on the actual situation of the substation; those not involved will not be deployed.

[0079] Example 2

[0080] Methods for obtaining monitoring data:

[0081] Install a monitoring terminal on the equipment or its auxiliary facilities.

[0082] The monitoring terminal records and outputs the maximum measurement value within 30 seconds every 30 seconds. The unit is V / m.

[0083] Data is continuously monitored and output according to the rule of year-month-day-hour-minute-second measurement point number-L.

[0084] The numbering should be unique. For example, the incoming line side of the transformer body can be represented by ①-L.

[0085] Measurements will not be taken during rainy or snowy weather.

[0086] Example 3

[0087] Methods for calculating occupational exposure levels to power frequency electromagnetic fields:

[0088] Method 1: Calculation of actual occupational exposure levels on an 8-hour workday;

[0089] (Step 1): Calculate the source value for each region

[0090] The source value of the region is represented by L.

[0091] L= ......................(Formula 1)

[0092] Calculate the L value for the main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area respectively.

[0093] n represents the total number of measurements taken in each area within 8 hours.

[0094] This represents the measured value at each measuring point.

[0095] The calculated L values ​​are denoted as L. 主变区 L 高抗区 L 配电装置区 L 无功补偿区

[0096] (Step 2): Calculate the actual level of occupational exposure for 8 hours.

[0097] 8 hours of actual occupational exposure level (using L) 8h express

[0098] L 8h = ... (Equation 2)

[0099] t represents the actual contact time in each area during an 8-hour work shift, expressed in hours.

[0100] Areas without corresponding control measures are not included in the calculation.

[0101] Method 2: Calculation of 8-hour occupational exposure instantaneous predictive level;

[0102] (Step 1): Calculate the source value for a 30-second time period for each region;

[0103] Calculate the source value L for each of the following areas within a 30-second time period: main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area. 30s , to obtain L 主变区30s L 高抗区30s L 配电装置区30s L 无功补偿区30s ;

[0104] L 30s =

[0105] In the formula: m represents the number of measuring points, This represents the measured value at each measuring point;

[0106] According to the obtained L 主变区30s L 高抗区30s L 配电装置区30s L 无功补偿区30s Calculate the 8-hour occupational exposure prediction level L 8h预测 ;

[0107] L 8h预测 =

[0108] Where: n 主变区 This represents the number of main transformers. In a three-phase configuration, one phase equals one transformer.

[0109] k 主变区 This represents the number of measuring points on the main transformer.

[0110] n 高抗区 This represents the number of high-resistance units; one phase equals one unit.

[0111] k 高抗区 This represents the number of high-resistance testing points.

[0112] n 配电区 This represents the number of times the line has been used.

[0113] k 配电区 This represents 4 times the number of measurement points in the power distribution area.

[0114] n 无功补偿区 This represents the number of capacitor or reactor groups.

[0115] k 无功补偿区 This represents the number of measuring points in the reactive power compensation zone.

[0116] The actual level of 8 hours of occupational exposure L 8h Or 8-hour occupational exposure prediction level L 8h预测 If the exposure level is within the occupational exposure limit, it is considered compliant; if it exceeds the occupational exposure limit, it indicates that the exposure level is too high during this period. A warning will be issued and targeted control and protection measures will be taken. The occupational exposure limit is 5000V / m.

[0117] Example 4

[0118] Online monitoring system for occupational exposure levels of power frequency electric fields

[0119] It includes a power frequency electric field monitoring terminal device, which is a three-phase sensor that responds to 50Hz.

[0120] One method for installing a monitoring terminal is as follows: it is fixedly installed on the equipment or its auxiliary facilities at a height of 1.5m above the ground being inspected.

[0121] This includes an online monitoring and data processing system for occupational exposure levels to power frequency electric fields, housed in a control room mainframe. The system comprises a memory, a processor, and a computer program stored in the memory and executable on the processor. The core algorithm of the processing system is the same as in Methods 1 and 2. For simplicity, it will not be elaborated further here.

[0122] It should be understood that a processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0123] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0124] The core algorithm of the system is the same as that of methods 1 and 2. Each step can be completed by the integrated logic circuit in the processor or by instructions in the form of software, and the results are fed back to the monitoring terminal.

[0125] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for online monitoring of occupational exposure levels in power frequency electric fields of substations, characterized in that, Includes the following steps: Step 1: Based on the substation voltage level and typical design content, deploy online monitoring points in the main transformer area, AIS distribution area, HGIS distribution area, and reactive power compensation area. Step 2: Install a monitoring terminal on the substation or its auxiliary facilities. The monitoring terminal records and outputs the maximum measurement value within 30 seconds every 30 seconds. Data is continuously monitored and transmitted to the control host; Step 3: Calculate the monitored data according to the method of the present invention to obtain the worker's 8-hour occupational exposure level to power frequency electromagnetic field, in order to monitor and determine whether the worker's occupational exposure level meets the requirements of the national occupational exposure limit. The specific calculation of the worker's 8-hour occupational exposure to power frequency electromagnetic fields is as follows: Step 3-1: Calculate the actual occupational exposure level for an 8-hour workday; Calculate the source value L for each of the main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area, and denote it as L. 主变区 L 高抗区 L 配电装置区 L 无功补偿区 ; L= In the formula: n represents the total number of measurements taken in each area within 8 hours, L i Represents the measured values ​​at each measuring point in each region; According to the obtained L 主变区 L 高抗区 L 配电装置区 L 无功补偿区 Calculate the actual level of occupational exposure (L) for 8 hours 8h ; L 8h = In the formula: t is the actual contact time of each area in an 8-hour work shift; Step 3-2, adjust the actual level of occupational exposure (L) for 8 hours. 8h If the occupational exposure limit is not exceeded when compared with the occupational exposure limit, it means that the requirements are met. If the occupational exposure limit is exceeded, it indicates non-compliance, and control and protective measures should be taken.

2. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 1, characterized in that, The method for calculating the level of occupational exposure to power frequency electromagnetic fields during an 8-hour workday can also predict the level by assessing the actual occupational exposure over the 8-hour period; the specific steps are as follows. Calculate the source value L for each of the following areas within a 30-second time period: main transformer area, high-resistance area, power distribution equipment area, and reactive power compensation area. 30s , to obtain L 主变区30s L 高抗区30s L 配电装置区30s L 无功补偿区30s ; L 30s = In the formula: m represents the number of measuring points in each area, Represents the measured values ​​at each measuring point in each region; According to the obtained L 主变区30s L 高抗区30s L 配电装置区30s L 无功补偿区30s Calculate the 8-hour occupational exposure prediction level L 8h预测 ; L 8h预测 = Where: n 主变区 This represents the number of main transformers; in a three-phase configuration, one phase equals one transformer. 主变区 n represents the number of measuring points on the main transformer. 高抗区 Represents the number of high-resistance units; one phase equals one unit; k 高抗区 n represents the number of high-resistance testing points; 配电区 k represents the number of loops; 配电区 n represents 4 times the number of measurement points in the power distribution area. 无功补偿区 k represents the number of capacitor or reactor groups. 无功补偿区 This represents the number of measuring points in the reactive power compensation zone; 8-hour occupational exposure prediction level L 8h预测 If the exposure level is within the occupational exposure limit, it is considered compliant; if it exceeds the occupational exposure limit, it indicates that the exposure level is too high during this period. In such cases, a warning will be issued and targeted control and protection measures will be taken.

3. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 1, characterized in that, The deployment method of the online monitoring points in the main transformer area is as follows: The online monitoring points for the 110kV main transformer area include one point on the incoming line side of the transformer body and one point on the outgoing line side of the transformer body. The online monitoring points for the 220kV / 330kV main transformer area include: one point on the incoming line side of the transformer body; one point on the outgoing line side of the transformer body; one point on each side of the transformer body; one point on the transformer surge arrester; and one point on the transformer voltage transformer. The online monitoring points for the 500 / 750 / 1000kV main transformer area include: 1 point on the incoming line side of the transformer body; 1 point on the outgoing line side of the transformer body; 1 point on each side of the transformer body; 1 point on the transformer surge arrester; 1 point on the transformer voltage transformer; 1 point on the transformer neutral point reactor; and 1 point on the transformer neutral point voltage transformer.

4. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 3, characterized in that, The AIS distribution area online monitoring points include 1 point for line surge arresters; 1 point for line disconnect switches; and 1 point for line switches. One point for the line current transformer.

5. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 4, characterized in that, The HGIS power distribution area online monitoring points include 1 point for line surge arresters; 1 point for line disconnect switches; and 1 point for line switches. One point for the line current transformer.

6. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 5, characterized in that, The online monitoring points for the reactive power compensation area include: one point at the head of the 10kV / 35kV / 66kV overhead busbar; one point in the middle of the 10kV / 35kV / 66kV overhead busbar; one point at the tail of the 10kV / 35kV / 66kV overhead busbar; one point for the 10kV / 35kV / 66kV capacitor; and one point for the 10kV / 35kV / 66kV reactor.

7. The online monitoring method for occupational exposure levels of power frequency electric fields in substations according to claim 1, characterized in that, The monitoring terminal is 1.5m above the ground being inspected.

8. An online monitoring system for occupational exposure levels in power frequency electric fields of substations, characterized in that, include: The memory, processor, and computer program stored in the memory and capable of running on the processor execute the online monitoring method for occupational exposure levels of power frequency electric fields in substations as described in any one of claims 1-7.

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