Voltage monitor precision measurement method, device, equipment and storage medium

Abstract

The application relates to the technical field of power distribution network and discloses a voltage monitor precision measurement method, device, equipment and storage medium, the method comprising the following steps: when it is detected that the precision of a voltage monitor at a power distribution station reaches a preset precision requirement, obtaining a high-voltage side voltage value of the power distribution station; obtaining a first-end voltage value of a power distribution area based on the high-voltage side voltage value and a transformer transformation ratio; obtaining a first-end measurement voltage value of the power distribution area through a first-end voltage monitor; and determining the precision corresponding to the first-end voltage monitor based on the first-end voltage value and the first-end measurement voltage value. Since the first-end voltage value of the power distribution area is obtained based on the high-voltage side voltage of the power distribution station and the transformer transformation ratio, and the precision corresponding to the first-end voltage monitor is determined based on the first-end voltage value and the first-end measurement voltage value, the problem that the precision of the voltage monitor cannot be evaluated in real time in the prior art, thereby failing to provide an accurate voltage qualification rate, is solved.

Description

Technical Field

[0001] This invention relates to the field of power distribution network technology, and in particular to a method, apparatus, equipment and storage medium for measuring the accuracy of a voltage monitoring instrument. Background Technology

[0002] With the rapid development of my country's economy, the use of electricity is becoming increasingly widespread. Voltage quality directly affects the operating characteristics of electrical equipment. Excessive voltage may burn out electrical appliances, while insufficient voltage may prevent equipment from starting properly. Precision equipment has even stricter requirements for voltage quality. Therefore, voltage quality is directly related to the national economy and people's livelihoods, and influences national economic development.

[0003] In existing schemes, the National Energy Administration stipulates that each 10kV busbar supplying power to a region in the low-voltage distribution network must be equipped with a voltage monitoring instrument to continuously monitor voltage quality. The voltage qualification rate standard is typically used. For every 100 distribution transformer substations in a 10kV / 0.4kV substation area, one substation is selected, with a monitoring point set at each end of that substation. Since the accuracy of the voltage monitoring instrument directly determines the reliability of the voltage qualification rate, although the standard requires that the voltage monitoring instrument accuracy be calibrated every three years, the complex distribution network environment can easily lead to a decrease in the accuracy of the voltage monitoring instrument, or even its failure to meet the requirements. It is possible that some voltage monitoring instruments will show inaccuracies more than three years later. Therefore, how to assess the accuracy of voltage monitoring instruments in real time has become an urgent problem to be solved.

[0004] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this invention is to provide a method, apparatus, device, and storage medium for measuring the accuracy of a voltage monitor, aiming to solve the technical problem in the prior art that the accuracy of a voltage monitor cannot be evaluated in real time, resulting in the inability to provide an accurate voltage pass rate.

[0006] To achieve the above objectives, the present invention provides a method for measuring the accuracy of a voltage monitoring instrument, the method comprising the following steps:

[0007] When the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirements, the high-voltage side voltage value of the distribution network substation is acquired.

[0008] The voltage value at the beginning of the distribution substation is obtained based on the high-voltage side voltage value and the transformer transformation ratio.

[0009] The measured voltage value at the beginning of the distribution transformer area is obtained by a voltage monitoring instrument at the beginning of the transformer.

[0010] The accuracy of the head-end voltage monitor is determined based on the head-end voltage value and the head-end measured voltage value.

[0011] Optionally, before the step of obtaining the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirement, the method further includes:

[0012] Obtain the measured voltage and current values ​​at the distribution network substation side;

[0013] Obtain the length and model of the first transmission line in the distribution network substation, and obtain the first impedance and first admittance of the first transmission line based on the length and model.

[0014] The high-voltage side voltage value of the distribution network substation is determined based on the measured voltage value, the measured current value, the first impedance, and the first admittance.

[0015] The high-voltage side voltage value is obtained by the target voltage detection equipment at the distribution network substation.

[0016] The accuracy of the voltage monitor is determined based on the high-voltage side voltage value and the high-voltage side measured voltage value.

[0017] Optionally, the step of determining the high-voltage side voltage value of the distribution network substation based on the measured voltage value, the measured current value, the first impedance, and the first admittance includes:

[0018] Based on the measured voltage value, the measured current value, the first impedance, and the first admittance, the high-voltage side voltage value of the distribution network substation is determined by a preset voltage calculation formula;

[0019] The preset voltage calculation formula is as follows:

[0020]

[0021] In the formula, U2 is the high-voltage side voltage value, U1 is the measured voltage value, Z is the first impedance, Y is the first admittance, and I1 is the measured current value.

[0022] Optionally, the step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value includes:

[0023] Based on the first-end voltage value and the first-end measured voltage value, the first-end error value corresponding to the first-end voltage monitor is determined by a preset accuracy error calculation formula;

[0024] The accuracy of the first-end voltage monitor is determined based on the first-end error value.

[0025] The formula for calculating the preset accuracy error is as follows:

[0026]

[0027] In the formula, The accuracy corresponding to the aforementioned first-end voltage monitoring instrument. Measure the voltage value at the first end. The voltage value at the first end is denoted as .

[0028] Optionally, after the step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value, the method further includes:

[0029] The terminal voltage value of the distribution transformer area is obtained by the terminal voltage monitor, and the terminal voltage value of the distribution transformer area is obtained by the target terminal meter.

[0030] Obtain the usage time of the terminal voltage monitor;

[0031] When the usage time does not exceed the preset time, the measurement error sequence of the terminal voltage monitor is determined based on the terminal measured voltage value and the terminal voltage value;

[0032] The accuracy of the terminal voltage monitor is determined by the measurement error sequence.

[0033] Optionally, after the step of obtaining the usage time of the terminal voltage monitor, the method further includes:

[0034] When the usage duration exceeds the preset duration, the historical monthly error sequence of the month corresponding to the measurement error sequence in the target historical period is obtained;

[0035] Obtain the current monthly error sequence corresponding to the month in the current time period of the target measurement error sequence;

[0036] The monthly average error value is obtained by using the historical monthly error sequence and the current monthly error sequence;

[0037] The accuracy of the terminal voltage monitor is determined by the monthly average error value.

[0038] Optionally, after the step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value, the method further includes:

[0039] The target head-end voltage value of the distribution station area is collected by the head-end voltage monitor within a preset period.

[0040] The number of times the upper voltage limit is exceeded and the number of times the lower voltage limit is exceeded are obtained based on the target voltage limit and the target first-end voltage value.

[0041] The voltage qualification rate of the first end of the distribution transformer area is obtained based on the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit.

[0042] A full assessment of the end voltage qualification rate is performed based on the aforementioned first-end voltage qualification rate.

[0043] Furthermore, to achieve the above objectives, the present invention also proposes a voltage monitoring instrument accuracy measurement device, the device comprising:

[0044] The accuracy detection module is used to acquire the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation reaches the preset accuracy requirement.

[0045] The voltage acquisition module is used to acquire the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio;

[0046] The voltage measurement module is used to obtain the measured voltage value at the beginning of the distribution substation through the beginning voltage monitor;

[0047] The accuracy determination module is used to determine the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value.

[0048] Furthermore, to achieve the above objectives, the present invention also proposes a voltage monitoring instrument accuracy measurement device, the device comprising: a memory, a processor, and a voltage monitoring instrument accuracy measurement program stored in the memory and executable on the processor, the voltage monitoring instrument accuracy measurement program being configured to implement the steps of the voltage monitoring instrument accuracy measurement method as described above.

[0049] In addition, to achieve the above objectives, the present invention also proposes a storage medium storing a voltage monitor accuracy measurement program, wherein when the voltage monitor accuracy measurement program is executed by a processor, it implements the steps of the voltage monitor accuracy measurement method as described above.

[0050] This invention discloses a method for acquiring the high-voltage side voltage value of the distribution substation when the accuracy of the voltage monitoring instrument at the distribution substation meets the preset accuracy requirements; acquiring the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio; acquiring the first-end measured voltage value of the distribution substation through the first-end voltage monitoring instrument; and determining the accuracy corresponding to the first-end voltage monitoring instrument based on the first-end voltage value and the first-end measured voltage value. Compared to the prior art, which periodically verifies the accuracy of the voltage monitoring instrument every three years, leading to the problem that the voltage monitoring instrument fails to meet the accuracy requirements earlier than three years due to complex distribution network environments, this invention solves the technical problem in the prior art that the accuracy of the voltage monitoring instrument cannot be evaluated in real time, resulting in the inability to provide an accurate voltage qualification rate, thereby improving the voltage quality of the low-voltage distribution network. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the structure of the voltage monitoring accuracy measurement device in the hardware operating environment involved in the embodiments of the present invention;

[0052] Figure 2 This is a flowchart illustrating the first embodiment of the voltage monitoring instrument accuracy measurement method of the present invention;

[0053] Figure 3 This is a schematic diagram of the power distribution network structure in the first embodiment of the voltage monitoring instrument accuracy measurement method of the present invention;

[0054] Figure 4 This is an equivalent model of the first transmission line in the first embodiment of the voltage monitoring instrument accuracy measurement method of the present invention;

[0055] Figure 5 This is a flowchart illustrating the second embodiment of the voltage monitoring instrument accuracy measurement method of the present invention;

[0056] Figure 6 This is a flowchart illustrating the third embodiment of the voltage monitoring instrument accuracy measurement method of the present invention;

[0057] Figure 7 This is a structural block diagram of the first embodiment of the voltage monitoring accuracy measurement device of the present invention.

[0058] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0059] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0060] Reference Figure 1 , Figure 1 This is a schematic diagram of the voltage monitoring accuracy measurement device structure in the hardware operating environment involved in the embodiments of the present invention.

[0061] like Figure 1 As shown, the voltage monitoring accuracy measurement device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be high-speed random access memory (RAM) or stable non-volatile memory (NVM), such as a disk storage device. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0062] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the accuracy measurement device of the voltage monitor, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0063] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a voltage monitoring instrument accuracy measurement program.

[0064] exist Figure 1 In the voltage monitoring accuracy measurement device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and memory 1005 in the voltage monitoring accuracy measurement device of the present invention can be set in the voltage monitoring accuracy measurement device, and the voltage monitoring accuracy measurement device calls the voltage monitoring accuracy measurement program stored in the memory 1005 through the processor 1001 and executes the voltage monitoring accuracy measurement method provided in the embodiment of the present invention.

[0065] This invention provides a method for measuring the accuracy of a voltage monitoring instrument, referring to... Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the voltage monitoring instrument accuracy measurement method of the present invention.

[0066] In this embodiment, the voltage monitoring instrument accuracy measurement method includes the following steps:

[0067] Step S10: When the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirements, the high-voltage side voltage value of the distribution network substation is obtained.

[0068] It should be noted that the execution subject of the method in this embodiment can be a voltage monitoring instrument accuracy measuring device for measuring the accuracy of voltage monitoring instruments in low-voltage distribution networks, or other voltage monitoring instrument accuracy measuring systems that can achieve the same or similar functions and include such voltage monitoring instrument accuracy measuring devices. Here, the voltage monitoring instrument accuracy measuring system (hereinafter referred to as the system) is used to specifically describe the voltage monitoring instrument accuracy measuring methods provided in this embodiment and the following embodiments.

[0069] It should be understood that, according to the voltage monitoring instrument setting guidelines, each 10kV busbar in a regional power supply system needs to be equipped with a monitoring point, and one transformer substation out of every 100 substations in the 10kV / 0.4kV distribution transformer area should be selected, with one monitoring point set at each end of that substation. For example... Figure 3 As shown, Figure 3 This is a schematic diagram of the distribution network structure in this embodiment. The distribution network substation can transform the voltage to 10kV through a transformer, and then transmit the power to the low-voltage user end through a 10kV line. Typically, the electrical equipment of low-voltage users cannot use 10kV voltage, so it is necessary to transform the 10kV to 380V (i.e., line voltage, corresponding to a phase voltage of 220V) through a 10kV / 0.4kV low-voltage distribution transformer. Usually, one 10kV line can supply power to dozens of distribution transformers. Therefore, it can be assumed that there are two voltage monitoring instruments on the low-voltage side corresponding to each 10kV line. The voltage monitoring instrument at the aforementioned distribution network substation can be the voltage monitoring instrument installed at the 10kV busbar in the low-voltage distribution network, i.e. Figure 3 Voltage monitoring device in the middle.

[0070] It should be noted that the above-mentioned preset accuracy requirement can be the accuracy of the voltage value measured by the voltage monitor. If the measurement error of the voltage monitor is small, it means that the accuracy of the voltage monitor meets the preset accuracy requirement. The preset accuracy requirement can be set according to the voltage requirements of the electrical equipment or other actual conditions. This embodiment does not limit this.

[0071] It is understandable that the above high-voltage side voltage values ​​can be the voltage values ​​on the high-voltage side of a 10kV / 0.4kV distribution transformer in a low-voltage distribution network. In practical applications, such as... Figure 3 As shown, it can be taken Figure 3 The connection point between the 10kV busbar and the 10kV line is considered the starting point, and the connection point between any 10kV / 0.4kV distribution transformer and the 10kV line is considered the ending point. The voltage value at the end of the transmission line is the same as the high-voltage side voltage value mentioned above. The voltage value at the starting point can be calculated using this model, and according to Kirchhoff's voltage law, it can be obtained as follows:

[0072]

[0073] In the formula, I 11 U is the current at the beginning of the transmission line. 11 U is the voltage at the beginning of the transmission line. 12 Z' is the voltage at the end of the transmission line, Z' is the impedance of the transmission line, and Y' is the admittance of the transmission line.

[0074] It should be noted that, according to Figure 4 As can be seen from the equivalent model of the transmission line, if the above high-voltage side voltage value is to be obtained, the voltage at the beginning of the transmission line needs to be obtained. The voltage at the beginning is obtained by measuring the voltage monitoring instrument at the distribution substation. Therefore, the accuracy of the voltage monitoring instrument at the distribution substation will affect the high-voltage side voltage value. When obtaining the high-voltage side voltage value, it is necessary to test the accuracy of the voltage monitoring instrument at the distribution substation.

[0075] Furthermore, to make the obtained high-voltage side voltage value more accurate, before step S10, the method further includes: obtaining the measured voltage value and measured current value at the distribution network substation side; obtaining the length and model of the first transmission line in the distribution network substation, and obtaining the first impedance and first admittance of the first transmission line based on the length and model; determining the high-voltage side voltage value of the distribution network substation based on the measured voltage value, the measured current value, the first impedance and the first admittance; obtaining the high-voltage side measured voltage value through the target voltage detection device at the distribution network substation; and determining the accuracy of the voltage monitoring instrument based on the high-voltage side voltage value and the high-voltage side measured voltage value.

[0076] It should be understood that the above-mentioned measured voltage value can be the voltage value at the connection point between the 10kV bus and the 10kV line in a low-voltage distribution network. In practical applications, it can be obtained by measuring the voltage using a voltage monitoring instrument at the 10kV bus.

[0077] It is understood that the measured current value mentioned above can be the current value at the connection between the 10kV bus and the 10kV line in a low-voltage distribution network. In practical applications, it can be obtained by measuring with a meter installed on the distribution network substation side.

[0078] It should be noted that the aforementioned first transmission line can be a line that transmits electricity, with the connection point between the 10kV busbar and the 10kV line in the low-voltage distribution network as its starting point and any connection point between the 10kV / 0.4kV distribution transformer and the 10kV line as its ending point. When the length and type of the aforementioned transmission line from its starting point to its ending point are known, the first impedance and first admittance of the first transmission line can be obtained through the line length and type.

[0079] It is understood that the aforementioned target voltage detection equipment can be devices for measuring bus voltage in low-voltage distribution networks, such as bus protection devices, metering devices, and fault recording devices.

[0080] It should be understood that, according to the setting principles of voltage monitoring instruments, a monitoring point can be set at the 10kV busbar, so that the voltage U1 at the beginning of the aforementioned transmission line can be obtained through the voltage monitoring instrument at this monitoring point. Simultaneously, a meter can be installed at the distribution network substation to obtain the current on the distribution network substation side (i.e., the current I1 at the beginning of the aforementioned transmission line). When the length and type of the aforementioned transmission line from beginning to end are known, the impedance Z and admittance Y of the aforementioned transmission line are also known. Figure 4 As shown, the aforementioned first transmission line can be equivalent to... Figure 4 The model shown obtains the high-voltage side voltage value of the distribution network substation through a preset voltage calculation formula:

[0081]

[0082] In the formula, U2 is the high-voltage side voltage value, U1 is the measured voltage value, Z is the first impedance, Y is the first admittance, and I1 is the measured current value.

[0083] Since the measured voltage value U1, the first impedance Z, the first admittance Y, and the measured current value I1 are all known in the formula, the high-voltage side voltage value U2 can be obtained through the above formula. Therefore, if the accuracy of the voltage monitoring instrument at the distribution substation does not meet the requirements, the obtained high-voltage side voltage value of the distribution substation will be inaccurate. Thus, before obtaining the high-voltage side voltage value, it is necessary to test the accuracy of the voltage monitoring instrument at the distribution substation to check whether its accuracy meets the requirements. In practical applications, the device with the highest measurement accuracy among the target voltage detection devices mentioned above can be selected as the accurate voltage value for the 10kV bus. (i.e., the aforementioned high-voltage side measured voltage value), after obtaining the high-voltage side voltage value U2 and the high-voltage side measured voltage value Then, based on the high-voltage side voltage value U2 and the high-voltage side measured voltage value... The difference is used to assess the accuracy of the voltage monitoring instrument at the distribution network substation. If the accuracy of the voltage monitoring instrument is relatively high, the high-voltage side voltage value of the distribution network substation can be obtained, making the obtained high-voltage side voltage value more accurate.

[0084] In specific implementations, such as Figure 3 As shown, in low-voltage distribution networks, according to the installation guidelines for voltage monitoring devices, one voltage monitoring device needs to be installed on each 10kV busbar in a regional power supply area. Figure 3 (Medium voltage monitoring instrument), and in every 100 distribution transformer areas, one transformer area is selected, and one voltage monitoring instrument is installed at the beginning and end of that transformer area (respectively...). Figure 3 (The first-end voltage monitor and the last-end voltage monitor in the middle) Figure 3 The connection point between the 10kV busbar and the 10kV line is the starting point, and the connection point between any 10kV / 0.4kV distribution transformer and the 10kV line is the ending point. The high-voltage side voltage of the distribution network substation can be obtained from the voltage value at this ending point. Figure 4 According to the equivalent model of the transmission line and Kirchhoff's voltage law, the high-voltage side voltage value can be obtained by acquiring the measured voltage and current values ​​at the distribution substation side, as well as the impedance and admittance of the first transmission line in the distribution substation. In addition, in order to obtain an accurate high-voltage side voltage value, it is necessary to test the accuracy of the voltage monitoring instrument. If the measurement error of the voltage monitoring instrument is within a preset range (e.g., not exceeding 0.5), a relatively accurate high-voltage side voltage value can be obtained.

[0085] Step S20: Obtain the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio.

[0086] It should be noted that the aforementioned distribution transformer area can be any 10kV / 0.4kV distribution transformer area in a low-voltage distribution network. Correspondingly, the transformer transformation ratio can be the transformation ratio of the distribution transformer in the 10kV / 0.4kV distribution transformer area. Given the high-voltage side voltage value U2 and the transformer transformation ratio k, the formula can be used: U a =U2 / k This gives the starting voltage value U of the aforementioned distribution substation. a .

[0087] Step S30: Obtain the measured voltage value at the beginning of the distribution transformer area using a beginning voltage monitor.

[0088] It should be understood that the aforementioned head-end voltage monitoring device can be a voltage monitoring device installed at the head end of any 10kV / 0.4kV distribution transformer area in a low-voltage distribution network.

[0089] It is understandable that the above-mentioned measured voltage value at the beginning can be the voltage value at the beginning of the 10kV / 0.4kV transformer substation area in the low-voltage distribution network measured by the beginning voltage monitoring instrument.

[0090] Step S40: Determine the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value.

[0091] It should be noted that after obtaining the aforementioned first-end voltage value and the aforementioned first-end measured voltage value, the first-end error value corresponding to the first-end voltage monitor can be determined by using a preset accuracy error calculation formula, and the accuracy of the first-end voltage monitor can be determined based on the first-end error value. The preset accuracy error calculation formula is as follows:

[0092]

[0093] In the formula, The accuracy corresponding to the aforementioned first-end voltage monitoring instrument. The voltage value measured at the aforementioned first end is... The voltage value at the first terminal is as described above.

[0094] In practical applications, if the error accuracy requirement of the voltage monitor is 0.5, the calculated error value of the first-end voltage monitor can be compared with 0.5. If the error value is less than or equal to 0.5, it means that the accuracy of the first-end voltage monitor meets the accuracy requirement; otherwise, it does not meet the accuracy requirement.

[0095] This embodiment discloses a method for acquiring the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation meets the preset accuracy requirements; acquiring the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio; acquiring the first-end measured voltage value of the distribution substation through the first-end voltage monitoring instrument; and determining the accuracy corresponding to the first-end voltage monitoring instrument based on the first-end voltage value and the first-end measured voltage value. Compared with the prior art, which periodically verifies the accuracy of the voltage monitoring instrument every three years, resulting in the voltage monitoring instrument failing to meet the accuracy requirements earlier than three years due to complex distribution network environments, this embodiment solves the technical problem in the prior art that the accuracy of the voltage monitoring instrument cannot be evaluated in real time, leading to the inability to provide an accurate voltage qualification rate, thereby improving the voltage quality of the low-voltage distribution network.

[0096] refer to Figure 5 , Figure 5 This is a flowchart illustrating the second embodiment of the voltage monitoring instrument accuracy measurement method of the present invention.

[0097] Based on the first embodiment described above, in order to measure the accuracy of the end voltage monitoring instrument of the 10kV / 0.4kV distribution transformer area in the low-voltage distribution network, in this embodiment, after step S40, the method further includes:

[0098] Step S501: Obtain the terminal voltage value of the distribution transformer area through the terminal voltage monitor, and obtain the terminal voltage value of the distribution transformer area through the target terminal meter.

[0099] It should be noted that the aforementioned terminal voltage monitoring device can be installed at the end of any 10kV / 0.4kV transformer substation in a low-voltage distribution network.

[0100] It is understandable that the above-mentioned terminal voltage measurement value can be the voltage value at the end of the 10kV / 0.4kV distribution transformer area in the low-voltage distribution network measured by the terminal voltage monitoring instrument.

[0101] It should be understood that, such as Figure 3 As shown, due to the large number of loads connected between the beginning and end of the distribution substation, the impedance and admittance of the transmission line between the beginning and end of the distribution substation are jointly determined by the transmission line and the load. However, the load is dynamic; for example, a resident's television may be on or off. Therefore, the impedance and admittance of the transmission line are difficult to determine. In this case, the accuracy of the end voltage monitoring instrument can be measured using the voltage value provided by a certain user meter (i.e., the target end meter mentioned above). In practical applications, although the accuracy of the end voltage value obtained through the target end meter is not high, and using the target end meter as a benchmark to measure the accuracy of the end voltage monitoring instrument is inaccurate, the short meter cycle means that the voltage measured by the target end meter can be considered to meet the accuracy requirements.

[0102] Step S502: Obtain the usage time of the terminal voltage monitor.

[0103] It is understandable that since voltage monitors need to be calibrated at the factory, it can be assumed that the voltage they measure meets the requirements within a certain period of time. At this time, the usage time of the aforementioned terminal voltage monitor can be obtained to determine whether the voltage value measured by the current terminal voltage monitor meets the requirements.

[0104] Step S503: When the usage time does not exceed the preset time, determine the measurement error sequence of the terminal voltage monitor based on the terminal measured voltage value and the terminal voltage value.

[0105] It should be noted that the aforementioned preset duration can be the time limit set to determine whether the accuracy of the voltage value measured by the terminal voltage monitor meets the requirements, such as six months or one year. This embodiment does not impose any restrictions on this. If the usage time of the terminal voltage monitor does not exceed the preset duration, the error between the terminal voltage value obtained by the terminal voltage monitor and the actual measured value is small, and it can be used to measure the accuracy of the terminal voltage monitor.

[0106] It should be understood that the above measurement error sequence can be the error sequence for a preset duration of use of the terminal voltage monitor. For example, if the preset duration is one year, then the measurement error sequence can be the error sequence of the voltage measured by the terminal voltage monitor for one year. In practical applications, the above measurement error sequence can be obtained through the measurement error sequence calculation formula, where the measurement error sequence calculation formula is:

[0107]

[0108] In the formula, Measure the voltage value at the above-mentioned end. The above refers to the terminal voltage value.

[0109] Step S504: Determine the accuracy of the terminal voltage monitor through the measurement error sequence.

[0110] Understandably, after obtaining the measurement error sequence through the measurement error sequence calculation formula, the value of the measurement error sequence can be compared with the error accuracy requirement of the terminal voltage monitor (e.g., 0.5). If the measurement error sequence of the terminal voltage monitor does not exceed the error accuracy requirement, then the accuracy of the terminal voltage monitor meets the requirements.

[0111] In practical implementation, when measuring the accuracy of the end-of-line voltage monitoring instrument in any 10kV / 0.4kV distribution transformer area in a low-voltage distribution network, the accuracy of the end-of-line voltage monitoring instrument can be measured using the voltage value provided by the meter of a certain user in that distribution transformer area. At the same time, the usage time of the end-of-line voltage monitoring instrument is detected. If the usage time of the end-of-line voltage monitoring instrument has not exceeded one year, the measurement error sequence of the end-of-line voltage monitoring instrument for one year can be calculated by using the end-of-line measured voltage value of the end-of-line voltage monitoring instrument and the end-of-line voltage value provided by the user's meter. The obtained measurement error sequence is then compared with the error accuracy requirement. If the measurement error sequence does not exceed the error accuracy requirement, it indicates that the accuracy of the end-of-line voltage monitoring instrument is relatively accurate; otherwise, it indicates that the accuracy of the end-of-line voltage monitoring instrument is abnormal.

[0112] Furthermore, when the usage time of the terminal voltage monitor exceeds a preset time, the accuracy of the terminal voltage monitor is measured. After step S504, the method further includes: when the usage time exceeds the preset time, obtaining the historical monthly error sequence of the month corresponding to the measurement error sequence in the target historical period; obtaining the current monthly error sequence of the month corresponding to the measurement error sequence in the target current period; obtaining the monthly average error value through the historical monthly error sequence and the current monthly error sequence; and determining the accuracy corresponding to the terminal voltage monitor through the monthly average error value.

[0113] It should be noted that the aforementioned target historical period can be the period corresponding to when the terminal voltage monitor is used after exceeding the preset time limit, such as one year or half a year after exceeding the preset time limit. This embodiment does not impose any restrictions on this. Correspondingly, the aforementioned historical monthly error sequence can be the error sequence of the month corresponding to when the terminal voltage monitor is used after exceeding the preset time limit.

[0114] It should be understood that the above-mentioned current monthly error sequence can be the error sequence of the terminal voltage monitor for the corresponding month within a preset time period.

[0115] Understandably, when the terminal voltage monitoring device has been in use for longer than a preset period, the monthly average error value ζ(mou) can be obtained based on the current error sequence of the corresponding month during the preset period of use, and the error sequence of the corresponding month after the preset period of use. If the error accuracy requirement of the terminal voltage monitoring device is 0.5, then when the value of ζ(mou) exceeds 0.5, it indicates that the accuracy of the terminal voltage monitoring device is abnormal; if the value of ζ(mou) does not exceed 0.5, it indicates that the accuracy of the terminal voltage monitoring device is accurate. The formula for calculating the monthly average error value is as follows:

[0116]

[0117] This embodiment can determine the measurement error sequence of the terminal voltage monitor by using the measured voltage value of the distribution substation terminal obtained by the terminal voltage monitor and the terminal voltage value of the distribution substation obtained by the target terminal meter when the usage time of the terminal voltage monitor does not exceed the preset time. The accuracy of the terminal voltage monitor can then be determined by using the measurement error sequence. When the usage time of the terminal voltage monitor exceeds the preset time, the monthly average error sequence can be obtained by using the historical monthly error sequence and the current monthly error sequence of the terminal voltage monitor. The accuracy of the terminal voltage monitor can then be determined by using the monthly average error sequence. This makes the measured accuracy of the terminal voltage monitor more accurate.

[0118] refer to Figure 6 , Figure 6 This is a flowchart illustrating the third embodiment of the voltage monitoring instrument accuracy measurement method of the present invention.

[0119] Based on the above embodiments, in order to evaluate the voltage qualification rate in low-voltage distribution networks, in this embodiment, after step S40, the method further includes:

[0120] Step S601: Collect the target head-end voltage value of the distribution station area within a preset period using the head-end voltage monitor.

[0121] It should be noted that in low-voltage distribution networks, for 10kV / 0.4kV distribution transformer areas, it is required to select one transformer area out of every 100 transformer areas and set up a measuring point at the beginning and end of the transformer area. However, the voltage qualification rate of the other 99 transformer areas is unknown, so it is necessary to evaluate the voltage qualification rate of the other 99 transformer areas.

[0122] It should be understood that the above-mentioned preset period can be the period of voltage value acquisition by the first-end voltage monitor. For example, the voltage acquisition period can be set to 5 minutes. This embodiment does not limit this.

[0123] It is understandable that the aforementioned target head-end voltage value can be the voltage value at the head end of all 10kV / 0.4kV transformer substations in the low-voltage distribution network, as measured by the head-end voltage monitoring instrument. In practical applications, the head-end voltage monitoring instrument can record the voltage value V at the head end of the 10kV / 0.4kV transformer substations in the low-voltage distribution network every five minutes. m (t).

[0124] Step S602: Obtain the number of times the upper voltage limit is exceeded and the number of times the lower voltage limit is exceeded based on the target voltage limit and the target first-end voltage value.

[0125] It should be noted that the above target voltage limit can be the maximum voltage that can be transmitted at the beginning of a 10kV / 0.4kV distribution transformer area in a low-voltage distribution network.

[0126] It should be understood that the target voltage value at the beginning of the terminal can be compared with the target voltage limit to determine whether the target voltage value at the beginning of the terminal exceeds the target voltage limit. If it exceeds the limit, the voltage value at the beginning of the terminal is recorded as exceeding the upper limit voltage. If it does not exceed the limit, the voltage value at the beginning of the terminal is recorded as exceeding the lower limit voltage. After comparing all the voltage values ​​at the beginning of the terminal with the target voltage limit, the number of times the voltage value exceeds the upper limit voltage and the number of times the voltage value exceeds the lower limit voltage are counted.

[0127] Step S603: Obtain the first-end voltage qualification rate of the distribution substation based on the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit.

[0128] It is understandable that the aforementioned head-end voltage qualification rate can be considered the qualification rate of the head-end voltage of the distribution transformer area. In practical applications, after obtaining the number of times the voltage exceeded the upper limit and the number of times the voltage exceeded the lower limit, the head-end voltage qualification rate can be calculated using the voltage qualification rate calculation formula. This allows us to calculate the voltage qualification rate of the head-end voltage for all transformer areas in the low-voltage distribution network. The voltage qualification rate calculation formula is as follows:

[0129]

[0130] In the formula, r is the above-mentioned first-end voltage qualification rate, o is the above-mentioned number of times the voltage exceeds the upper limit, and p is the above-mentioned number of times the voltage exceeds the lower limit.

[0131] Step S604: Perform a full evaluation of the end voltage qualification rate based on the first-end voltage qualification rate.

[0132] It should be noted that for low-voltage distribution networks, the National Energy Administration requires a voltage qualification rate greater than 95%. According to the preset voltage calculation formula, for the same transmission line, if the initial voltage and current are the same, only the line impedance affects the initial voltage; that is, as the number of lines increases, the voltage decreases approximately linearly. In practical applications, if a transmission line supplies power to one hundred distribution areas, without considering voltage regulation and reactive power compensation equipment, it can be assumed that once the initial voltage qualification rates of two adjacent distribution areas are respectively at the required and unsatisfactory levels, these points will be used as the dividing lines to find the corresponding unqualified and qualified points. For example, assuming the voltage qualification rate of the twenty-third distribution area on this transmission line is 95.5%, and the voltage qualification rate of the twenty-fourth distribution area is 94.6%, it can be considered that from the twenty-fourth distribution area onwards, the voltage qualification rates of the twenty-fourth distribution area and subsequent distribution areas do not meet the qualification rate requirements. When the voltage qualification rate fails to meet the requirements at the aforementioned dividing point due to low voltage (i.e., p>0), since the voltage at the end of the transmission line is lower than the voltage at the beginning, the dividing point for whether the voltage qualification rate at the end meets the qualification rate target will be earlier than that at the beginning. Therefore, based on this dividing point, we can look forward to find the transformer substations where the end voltage qualification rate fails to meet the target (since the power supply radius of a transformer substation is limited, the voltage at the beginning is usually 1.05 times the voltage at the end; based on this, we move forward to find the location of the corresponding end voltage monitoring device). First, the voltage value at the beginning dividing point can be obtained according to the preset voltage calculation formula (this voltage value is the average voltage value of the beginning voltage values). And obtain the terminal boundary voltage value based on this voltage value. The impedance of the transmission line is then obtained using a preset voltage calculation formula to determine the boundary location. A voltage monitoring instrument is then installed at the end of the low-voltage distribution area at this boundary location.

[0133]

[0134] It should be understood that if the voltage pass rate obtained by the voltage monitor at the aforementioned boundary location still does not meet the pass rate requirement, the voltage monitor originally installed at the beginning can be used at the end. In this case, the position of the voltage monitor is determined by the voltage pass rate deviation, and its corresponding beginning-end voltage is... If the voltage compliance rate measured by the voltage monitoring instrument previously installed at the boundary location is r1, then the starting voltage of the new boundary point can be determined based on the voltage compliance rate r1. Then, a new boundary position is obtained through a preset voltage calculation formula, and a voltage monitoring instrument is installed at the new boundary position to achieve a full assessment of the end-point voltage qualification rate.

[0135]

[0136] This embodiment obtains the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit by collecting the target voltage value and target voltage limit of the distribution substation using the voltage monitoring instrument at the beginning end. Based on the voltage qualification rate of the beginning end obtained from the number of times the voltage exceeds the upper limit and the lower limit, a full evaluation of the voltage qualification rate of the end end is performed. This allows for an objective voltage qualification rate of all beginning and end ends of the distribution substation without increasing the number of voltage monitoring instruments, thereby promoting the development of the distribution network and improving power reliability.

[0137] Furthermore, this embodiment of the invention also proposes a storage medium storing a voltage monitor accuracy measurement program, which, when executed by a processor, implements the steps of the voltage monitor accuracy measurement method described above.

[0138] Reference Figure 7 , Figure 7 This is a structural block diagram of the first embodiment of the voltage monitoring accuracy measurement device of the present invention.

[0139] like Figure 7 As shown, the voltage monitoring accuracy measurement device proposed in this embodiment of the invention includes:

[0140] The accuracy detection module 701 is used to acquire the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirements.

[0141] Voltage acquisition module 702 is used to acquire the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio;

[0142] Voltage measurement module 703 is used to obtain the measured voltage value at the beginning of the distribution substation through the beginning voltage monitor;

[0143] The accuracy determination module 704 is used to determine the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value.

[0144] This embodiment of the voltage monitoring instrument accuracy measurement device discloses that when the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirements, it acquires the high-voltage side voltage value of the distribution network substation; acquires the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio; acquires the first-end measured voltage value of the distribution substation through the first-end voltage monitoring instrument; and determines the accuracy corresponding to the first-end voltage monitoring instrument based on the first-end voltage value and the first-end measured voltage value. Compared with the prior art, which periodically verifies the accuracy of the voltage monitoring instrument every three years, resulting in the voltage monitoring instrument failing to meet the accuracy requirements earlier than three years due to complex distribution network environments, this embodiment solves the technical problem in the prior art that the accuracy of the voltage monitoring instrument cannot be evaluated in real time, leading to the inability to provide an accurate voltage qualification rate, thereby improving the voltage quality of the low-voltage distribution network.

[0145] Other embodiments or specific implementations of the voltage monitoring accuracy measurement device of the present invention can be referred to the above-described method embodiments, and will not be repeated here.

[0146] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0147] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0148] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory / random access memory, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0149] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method of measuring the accuracy of a voltage monitor, characterized by, The voltage monitoring instrument accuracy measurement method includes: When the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirements, the high-voltage side voltage value of the distribution network substation is acquired. The voltage value at the beginning of the distribution substation is obtained based on the high-voltage side voltage value and the transformer transformation ratio. The measured voltage value at the beginning of the distribution transformer area is obtained by a voltage monitoring instrument at the beginning of the transformer. The accuracy of the head-end voltage monitor is determined based on the head-end voltage value and the head-end measured voltage value. After the step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value, the method further includes: The target head-end voltage value of the distribution station area is collected by the head-end voltage monitor within a preset period. The number of times the upper voltage limit is exceeded and the number of times the lower voltage limit is exceeded are obtained based on the target voltage limit and the target first-end voltage value. The voltage qualification rate of the first end of the distribution transformer area is obtained based on the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit. If the first-end voltage qualification rate and the first-end voltage qualification rate of the adjacent distribution substations of the distribution substation are respectively in the state of meeting and not meeting the requirements, the adjacent distribution substations are determined as the dividing point; Determine the voltage value at the first end of the boundary point, and determine the voltage value at the end of the boundary point based on the voltage value at the first end of the boundary point, wherein the voltage value at the first end of the boundary point is 1.05 times the voltage value at the end of the boundary point; The boundary position is determined based on the terminal boundary voltage value, and a full assessment of the terminal voltage qualification rate is performed based on the voltage monitoring instrument at the boundary position.

2. The method of claim 1, wherein, Before the step of obtaining the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation is detected to meet the preset accuracy requirement, the method further includes: Obtain the measured voltage and current values ​​at the distribution network substation side; Obtain the length and model of the first transmission line in the distribution network substation, and obtain the first impedance and first admittance of the first transmission line based on the length and model. The high-voltage side voltage value of the distribution network substation is determined based on the measured voltage value, the measured current value, the first impedance, and the first admittance. The high-voltage side voltage value is obtained by the target voltage detection equipment at the distribution network substation. The accuracy of the voltage monitor is determined based on the high-voltage side voltage value and the high-voltage side measured voltage value.

3. The voltage monitoring instrument accuracy measurement method as described in claim 2, characterized in that, The step of determining the high-voltage side voltage value of the distribution network substation based on the measured voltage value, the measured current value, the first impedance, and the first admittance includes: Based on the measured voltage value, the measured current value, the first impedance, and the first admittance, the high-voltage side voltage value of the distribution network substation is determined by a preset voltage calculation formula; The preset voltage calculation formula is as follows: In the formula, U2 is the high-voltage side voltage value, U1 is the measured voltage value, Z is the first impedance, Y is the first admittance, and I1 is the measured current value.

4. The method of claim 1, wherein, The step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value includes: Based on the first-end voltage value and the first-end measured voltage value, the first-end error value corresponding to the first-end voltage monitor is determined by a preset accuracy error calculation formula; The accuracy of the first-end voltage monitor is determined based on the first-end error value. The formula for calculating the preset accuracy error is as follows: In the formula, is the precision corresponding to the head voltage monitor, is the head measurement voltage value, is the head voltage value.

5. The method of claim 1, wherein, After the step of determining the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value, the method further includes: The terminal voltage value of the distribution transformer area is obtained by the terminal voltage monitor, and the terminal voltage value of the distribution transformer area is obtained by the target terminal meter. Obtain the usage time of the terminal voltage monitor; When the usage time does not exceed the preset time, the measurement error sequence of the terminal voltage monitor is determined based on the terminal measured voltage value and the terminal voltage value; The accuracy of the terminal voltage monitor is determined by the measurement error sequence.

6. The method of claim 5, wherein the step of determining the accuracy of the voltage monitor comprises the step of: After the step of obtaining the usage time of the terminal voltage monitor, the method further includes: When the usage duration exceeds the preset duration, the historical monthly error sequence of the month corresponding to the measurement error sequence in the target historical period is obtained; Obtain the current monthly error sequence corresponding to the month in the current time period of the target measurement error sequence; The monthly average error value is obtained by using the historical monthly error sequence and the current monthly error sequence; The accuracy of the terminal voltage monitor is determined by the monthly average error value.

7. A voltage monitor accuracy measuring device, characterized by, The device includes: The accuracy detection module is used to acquire the high-voltage side voltage value of the distribution network substation when the accuracy of the voltage monitoring instrument at the distribution network substation reaches the preset accuracy requirement. The voltage acquisition module is used to acquire the first-end voltage value of the distribution substation based on the high-voltage side voltage value and the transformer transformation ratio; The voltage measurement module is used to obtain the measured voltage value at the beginning of the distribution substation through the beginning voltage monitor; The accuracy determination module is used to determine the accuracy of the head-end voltage monitor based on the head-end voltage value and the head-end measured voltage value. The accuracy determination module is further configured to: collect the target head-end voltage value of the distribution transformer area within a preset period using the head-end voltage monitor; obtain the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit based on the target voltage limit and the target head-end voltage value; obtain the head-end voltage qualification rate of the distribution transformer area based on the number of times the voltage exceeds the upper limit and the number of times the voltage exceeds the lower limit; if the head-end voltage qualification rate and the head-end voltage qualification rate of the adjacent distribution transformer area are respectively in the state of meeting and not meeting the requirements, determine the adjacent distribution transformer area as a boundary point; determine the head-end boundary point voltage value of the boundary point, and determine the end boundary voltage value based on the head-end boundary point voltage value, wherein the head-end boundary point voltage value is 1.05 times the end boundary voltage value; determine the boundary position based on the end boundary voltage value, and perform a full evaluation of the end voltage qualification rate based on the voltage monitor at the boundary position.

8. A voltage monitor accuracy measurement apparatus, characterized by, The device includes: a memory, a processor, and a voltage monitor accuracy measurement program stored in the memory and executable on the processor, the voltage monitor accuracy measurement program being configured to implement the steps of the voltage monitor accuracy measurement method as described in any one of claims 1 to 6.

9. A storage medium, characterized by The storage medium stores a voltage monitor accuracy measurement program, which, when executed by a processor, implements the steps of the voltage monitor accuracy measurement method as described in any one of claims 1 to 6.

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