CN216285463U - Power flow analyzer for power system - Google Patents
Power flow analyzer for power system Download PDFInfo
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- CN216285463U CN216285463U CN202122896217.3U CN202122896217U CN216285463U CN 216285463 U CN216285463 U CN 216285463U CN 202122896217 U CN202122896217 U CN 202122896217U CN 216285463 U CN216285463 U CN 216285463U
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Abstract
A power flow analyzer of an electric power system comprises a data acquisition module, a current regulation module and an analysis module, wherein the data acquisition module is used for acquiring voltage information and current information of a circuit in the electric power system and generating a voltage acquisition signal and a current acquisition signal; the current regulation module comprises a first current transformer and a regulation unit, wherein the secondary side of the first current transformer is connected with a current acquisition signal, and the primary side of the first current transformer generates a current regulation signal; the adjusting unit is used for adjusting the number of turns of a secondary side winding coil of the first current transformer participating in work and ensuring that the current value of the current adjusting signal is not lower than the minimum detection current threshold; the analysis module is used for carrying out power flow analysis according to the voltage acquisition signal and the current regulation signal. The utility model can solve the technical problem that the precision of the existing phase table and the existing security and measurement device is not enough due to too small load after the power transmission of the transformer substation of the power system is put into operation, greatly avoids the risk of power accidents and can help the power system to operate safely and stably.
Description
Technical Field
The utility model belongs to the technical field of power system analysis, and relates to a power flow analyzer of a power system.
Background
The power flow calculation of the power system is a basic calculation for researching the steady-state operation condition of the power system, is an indispensable important component in the planning and operation of the power system, and can acquire the operation condition of a power grid by carrying out power flow analysis.
The current power flow analyzer of the power system firstly acquires voltage information and current information of a circuit in the power system, and the voltage information and the current information are often acquired through a current transformer or a voltage transformer. However, when the load is too small after the power transmission of the power system substation is put into operation, the existing various protection and measurement and control devices and the phase meter cannot judge whether the transformation ratio, the phase and the polarity of the current transformer are correct, and the current data of the secondary side of the transformer cannot be tested. If the polarity judgment of the transformer is wrong or the secondary wiring is wrong, related relay protection, measurement and control, metering systems and the like cannot be put into operation correctly, and the occurrence of electric power accidents is likely to be caused.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a power flow analyzer of a power system aiming at the defects in the prior art, which amplifies a collected current collecting signal to be not lower than a minimum detection current threshold value by using a first current transformer so as to solve the problem that secondary side current data is difficult to test due to too small load after the power transmission of a transformer substation of the power system is put into operation at present.
In order to achieve the purpose, the utility model adopts the technical scheme that:
a power flow analyzer of an electric power system comprises a data acquisition module, a current regulation module and an analysis module,
the data acquisition module is used for acquiring voltage information and current information of a line in the power system and generating a voltage acquisition signal and a current acquisition signal;
the current adjusting module comprises a first current transformer and an adjusting unit, the secondary side of the first current transformer is connected with the current collecting signal, and the primary side of the first current transformer generates a current adjusting signal; the adjusting unit is used for adjusting the number of turns of a secondary side winding coil of the first current transformer participating in work and ensuring that the current value of the current adjusting signal is not lower than a minimum detection current threshold value;
the analysis module is used for carrying out power flow analysis according to the voltage acquisition signal and the current regulation signal.
Further, the data acquisition module is used for acquiring three-phase current information and three-phase voltage information of a circuit in the power system, the generated current acquisition signals comprise A-phase acquisition current, B-phase acquisition current and C-phase acquisition current, and the generated voltage acquisition signals comprise A-phase acquisition voltage, B-phase acquisition voltage and C-phase acquisition voltage;
the current regulation module is provided with three first current transformers which are used for amplifying the A-phase collected current, the B-phase collected current and the C-phase collected current by X times and then using the amplified currents as the current regulation signals, wherein X is a real number not less than 1.
Furthermore, the data acquisition module comprises an a-phase current output interface, a B-phase current output interface, a C-phase current output interface and a public end current output interface, wherein the current between the a-phase current output interface and the public end current output interface is the a-phase acquisition current, the current between the B-phase current output interface and the public end current output interface is the B-phase acquisition current, and the current between the C-phase current output interface and the public end current output interface is the C-phase acquisition current;
one end of a secondary side winding coil of the three first current transformers is respectively connected with the phase-A current output interface, the phase-B current output interface and the phase-C current output interface; m selection ports which are connected outwards are respectively arranged at different positions on a secondary side winding coil of each first current transformer, the M selection ports on each first current transformer correspond to the positions of the M selection ports on the coils of the other two current transformers, and M is a positive integer which is larger than 1; and the adjusting unit selects three selection ports at the same position on the secondary side winding coils of the three first current transformers each time to be connected with the common-end current output interface.
Furthermore, the data acquisition module comprises a voltage transformer and a second current transformer, wherein the primary side of the voltage transformer is connected with a voltage signal of a line in a power system, and the secondary side of the voltage transformer generates the voltage acquisition signal; the primary side of the second current transformer is connected with a current signal of a line in a power system, and the secondary side of the second current transformer generates the current acquisition signal.
Further, the analysis module is a single chip microcomputer.
Further, the power flow analyzer of the power system further comprises a display screen for displaying a current value including the current adjusting signal and a result obtained after power flow analysis is performed by the analysis module.
The utility model has the beneficial effects that: the power system power flow analyzer provided by the utility model can adjust the current acquisition signal to be not lower than the minimum detection current threshold value and then perform power flow analysis, solves the technical problem that the precision of the existing phase table and the protection and measurement device is not enough due to too small load after the power transmission of the transformer substation of the power system is put into operation at present, greatly avoids the risk of power accidents, and can help the power system to safely and stably operate.
Drawings
Fig. 1 is a schematic structural diagram of an implementation of a power flow analyzer of an electrical power system in an embodiment of the present invention;
fig. 2 is a schematic connection diagram of a power flow analyzer in use.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The embodiments of the present invention, and all other embodiments obtained by a person of ordinary skill in the art without any inventive step, are within the scope of the present invention.
It is to be understood that the terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
The terms "comprises" and "comprising" indicate the presence of the described features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
The utility model provides a power flow analyzer of a power system, which comprises a data acquisition module, a current regulation module and an analysis module, wherein the data acquisition module is used for acquiring voltage information and current information of a circuit in the power system and generating a voltage acquisition signal and a current acquisition signal. The voltage transformer and the current transformer can be generally used for acquiring the voltage acquisition signal and the current acquisition signal, and other feasible devices can be used for acquisition.
The voltage transformer is an instrument used for converting voltage, and the voltage transformer is mainly used for supplying power to a measuring instrument and a relay protection device and providing voltage information of a measured line. The basic structure of the voltage transformer is similar to that of a transformer, and comprises a primary winding and a secondary winding, wherein the primary winding and the secondary winding are both arranged on or wound on an iron core, the primary winding is connected with a measured line in parallel during the operation of the voltage transformer, and the secondary winding is connected with an instrument or a relay in parallel, so that when the voltage on a high-voltage line is measured, although the primary voltage is high, the secondary voltage is low, and the safety of operators and instruments can be ensured. In this embodiment, a primary side of the voltage transformer is connected to a voltage signal of a line in the power system, a voltage acquisition signal with a reduced voltage is generated at a secondary side of the voltage transformer, and the voltage acquisition signal is provided to the analysis module for power flow analysis of the power system.
The current transformer is an instrument for converting a large current on a primary side into a small current on a secondary side according to an electromagnetic induction principle to measure, in the embodiment, a current signal of a line in a power system is connected to the primary side of a second current transformer, and a current acquisition signal of the small current is generated on the secondary side of the second current transformer.
If the second current transformer is directly used for carrying out power flow analysis after generating the current acquisition signal, the situation that secondary side current data are difficult to test due to too small load after the power transmission of the power system transformer substation is put into operation may occur, and therefore the utility model also designs the current adjusting module for adjusting the current value of the current acquisition signal. The current regulation module provided by the utility model comprises a first current transformer and a regulation unit, wherein the secondary side of the first current transformer is connected with a current acquisition signal, and the primary side of the first current transformer generates a current regulation signal; the adjusting unit is used for adjusting the number of turns of the secondary side winding coil of the first current transformer participating in work so as to ensure that the current value of the current adjusting signal is not lower than the minimum detection current threshold value.
According to the utility model, a first current transformer is selected to amplify a current acquisition signal according to an electromagnetic induction principle and an ampere's law. According to the electromagnetic induction principle, the magnetic flux passing through the coil can be increased along with the increase of the number of turns, the currents passing through the secondary winding of the current transformer and the root wire core are the same, and if a current line to be measured is wound into the coil, the number of turns at the coil is the multiple of current amplification. Because the generated resistance is the same as that of the same wire core, errors in calculation can be naturally ignored and are not remembered, and by the method, the current regulation signal of the second current transformer, which is obtained after the secondary current (namely the current acquisition signal) is amplified by a plurality of times, is obtained. According to the ampere's law, the direction of the coil winding is consistent, the direction of the magnetic field is consistent, and the phase of the initial current is not influenced. Therefore, according to the electromagnetic induction principle and the ampere's law, the current amplitude of the current acquisition signal can be amplified by a plurality of times or even by a plurality of times according to the method under the condition of not changing the phase of the secondary current of the second current transformer. The amplification factor can be controlled through the adjusting unit according to actual needs, the adjusting unit controls the specific amplification factor of the current acquisition signal through controlling the number of turns of the secondary side winding coil of the first current transformer participating in work, the first current transformer serves as a current amplifier, and only the current value of the current adjustment signal obtained after amplification is required to be ensured not to be lower than a minimum detection current threshold value, and the minimum detection current threshold value is the minimum value which can be used for judging information such as the transformation ratio, the phase position, the polarity and the like of the current transformer.
After the voltage acquisition signal and the current regulation signal are obtained, the analysis module carries out power flow analysis according to the voltage acquisition signal and the current regulation signal to obtain the relevant information of the operation condition of the power grid, and the analysis module can be realized by adopting a conventional power flow analysis model and algorithm and adopting a single chip microcomputer.
The data acquisition module can be arranged on an electric power system, and the voltage acquisition signal and the current acquisition signal are acquired and then output through a port, as shown in fig. 2, a screen cabinet to be tested is a device which can be arranged in the electric power system and then output through the port, the voltage acquisition signal and the current acquisition signal acquired by the data acquisition module are output through a voltage wiring terminal and a current wiring terminal of the screen cabinet to be tested, and the transformer substation in the electric power system generally outputs three-phase alternating current, so that the voltage wiring terminal comprises four terminals providing phase a, phase B, phase C and common terminal voltages, namely a phase voltage output interface UA, a phase voltage output interface UB, a phase voltage output interface UC and a common terminal voltage output interface UN; the current wiring terminal comprises four terminals for providing A-phase, B-phase, C-phase and common-end currents, namely an A-phase current output interface IA, a B-phase current output interface IB, a C-phase current output interface IC and a common-end current output interface IN.
The current regulation module and the analysis module may be disposed on a single portable mobile detection and analysis device, as shown in fig. 2, on which access ports, i.e., a voltage test column and a current test column, are disposed for acquiring a voltage acquisition signal and a current acquisition signal output from a port of the data acquisition module. In order to correspondingly obtain three-phase acquisition signals, the voltage test columns comprise four test columns Ua, Ub, Uc and Un which receive voltages of an A phase, a B phase, a C phase and a public terminal, the current test columns comprise four test columns Ia, Ib, Ic and In which receive voltages of the A phase, the B phase, the C phase and the public terminal, voltage wiring terminals UA, UB, UC and UN are respectively connected with the voltage test columns Ua, Ub, Uc and Un through leads during tidal current analysis, and current wiring terminals IA, IB, IC and IN are respectively connected with the current test columns Ia, Ib, Ic and In through leads.
In the embodiment, the power system tide analyzer is applied to transformer substation on-load testing, the related screen cabinet to be tested comprises a protection screen, a fault recording screen, a measurement and control screen, a metering screen cabinet and the like, a data acquisition module acquires a voltage acquisition signal and a current acquisition signal and then outputs the signals through a voltage wiring terminal and a current wiring terminal which are arranged on the screen cabinet to be tested, and a voltage testing column and a current testing column which are arranged on a portable and movable detection and analysis device comprising a current adjusting module and an analysis module are connected.
As shown in fig. 2, besides the voltage testing column and the current testing column, in some embodiments, a display screen may be further disposed on the panel of the portable and movable detection and analysis device for displaying some information in the power flow analysis process, such as a voltage value of the voltage acquisition signal, a current value of the current adjustment signal, a result obtained after the power flow analysis performed by the analysis module, and the like. The power system tidal current analyzer can integrate the equipment power supply charging energy storage technology and provide a USB charging port as a charging port for an external power supply to provide electric energy for the power system tidal current analyzer. In addition, various types of buttons, such as a power-on button, a power-off button, a holding button, a backlight button, various display buttons and the like, can be further arranged on the panel of the portable and movable detection and analysis device and used for controlling the power flow analyzer of the power system to realize corresponding functions. And a panel of the portable movable detection and analysis device can be also provided with a current amplification adjusting knob connected with the current adjusting module, and the number of turns of the secondary side winding coil of the first current transformer connected in actual work is controlled by the current amplification adjusting knob.
Fig. 1 is a schematic diagram of the internal structure of a portable mobile detection and analysis device including a current regulation module and an analysis module. In this embodiment, the number of the first current transformers in the current regulation module is three, and the first current transformers are respectively used for amplifying the a-phase acquisition current, the B-phase acquisition current, and the C-phase acquisition current by X times and then used as current regulation signals, where X is a real number not less than 1. As shown In fig. 1, In this embodiment, the current testing columns Ia, Ib, Ic and In are respectively connected to the current connection terminals Ia, Ib, Ic and In of the screen cabinet to be tested, the current between the a-phase current output interface Ia and the common-end current output interface In is an a-phase collected current, and the current between the current testing columns Ia and In is also an a-phase collected current; the current between the B-phase current output interface IB and the common-end current output interface IN is B-phase collected current, and the current between the current testing columns Ib and IN is also B-phase collected current; the current between the C-phase current output interface IC and the public end current output interface IN is C-phase collected current, and the current between the current testing columns IC and IN is also C-phase collected current.
One end of a secondary side winding coil of the three first current transformers is respectively connected with an A-phase current output interface, a B-phase current output interface and a C-phase current output interface; m selection ports which are connected outwards are respectively arranged at different positions on a secondary side winding coil of each first current transformer, and the M selection ports on each first current transformer correspond to the positions of the M selection ports on the coils of the other two current transformers so as to ensure that the A-phase acquisition current, the B-phase acquisition current and the C-phase acquisition current are amplified by the same times, wherein M is a positive integer which is more than 1.
As shown in fig. 1, in this embodiment, each first current transformer is provided with 3 selection ports, which are respectively two ends and a middle position of the secondary winding coil of each first current transformer, and there are 9 selection ports in total. The adjusting unit selects three selecting ports at the same position on the winding coils at the secondary sides of the three first current transformers each time to be connected with the common-end current output interface. In this embodiment, a switch is used to implement the adjusting unit, as shown In fig. 1, the adjusting unit includes 9 switches, 3 × 3, first connection ends of the 9 switch devices are all connected to the current testing pillars In, and second connection ends of the 9 switch devices are respectively connected to 9 selection ports arranged on the winding coils on the secondary sides of the three first current transformers. The adjusting unit has 3 adjusting gears, when the adjusting unit is in the first gear, three switches correspondingly connected with one ends of the secondary side winding coils of the three first current transformers, which are connected with the A-phase current output interface, the B-phase current output interface and the C-phase current output interface, are closed, other switches are opened, and the amplification factor is minimum; when the three switches are in the second gear, the three switches correspondingly connected with the middle positions on the winding coils on the secondary sides of the three first current transformers are closed, other switches are opened, and the amplification factor is larger than the amplification factor of the first gear; when the three first current transformers are in a third gear, three switches which are correspondingly connected with one ends of the winding coils on the secondary sides of the three first current transformers, which are farthest away from the connection positions of the A-phase current output interface, the B-phase current output interface and the C-phase current output interface, are closed, other switches are opened, and the amplification factor is larger than that of the first gear and that of the second gear.
The embodiment is based on a phase meter testing principle, and a single chip microcomputer is applied to analyze and process data. And connecting a voltage acquisition signal provided by the screen cabinet to be tested into a voltage acquisition column of the portable movable inspection and analysis device to acquire voltage information required by tidal current analysis. According to the electromagnetic induction principle and the ampere's law, a current acquisition signal provided by a screen cabinet to be detected is connected to a current acquisition column, a first current transformer is arranged in a portable movable inspection and analysis device, the number of turns of a secondary side winding coil of the first current transformer is adjusted through a current amplification adjusting knob, an amplified current adjusting signal is obtained, the current value of the current adjusting signal is not lower than a minimum detection current threshold value, and current information required by tidal current analysis is obtained. The device power supply charging energy storage technology is integrated, so that the device is more convenient and faster in the use process, the high-precision power system tide analyzer is applied to the transformer substation on-load test, the advantages of simplicity, convenience, high efficiency and safety are achieved, and the popularization and application values are high. The specific test method is as follows:
the power system load flow analyzer is applied to a transformer substation load test, firstly, whether the polarity extraction of a current transformer is positive by a bus is determined, then, the output direction of electric energy is determined according to the load, and the load test is respectively carried out on a voltage (current) transformer secondary winding (namely a voltage transformer and a second current transformer which are provided with a data acquisition module) of an operation interval to be tested, a related protection screen, a related fault recording screen, a related measurement and control screen, a related metering screen cabinet and the like.
The device power-on key is pressed to check if the voltage (current) magnitude and phase are correct. If the current is less than 0.02A (in this embodiment, 0.02A is used as the minimum detection current threshold to satisfy the calculation accuracy, and the current amplification adjustment knob may be adjusted according to the actual situation during actual use), until the current is greater than 0.02A. And analyzing whether the secondary voltage is correct or not according to the primary voltage of the voltage transformer, wherein the voltage amplitude is normal generally at 56-62V, and the voltage phase three-phase angular difference is normal about 120 degrees. And analyzing whether the secondary current is correct or not according to the primary current of the first current transformer, wherein the current amplitude is normal by using three-phase balance, and the current phase is normal by using a three-phase angular difference of about 120 degrees. And determining the output direction of the electric energy by combining the load according to the polarity extraction direction of the current transformer, wherein if the directions of the current transformer and the load are the same, the condition that the phase difference between the voltage and the current is greater than 0 ℃ is qualified, and if the directions of the current transformer and the load are opposite, the condition that the phase difference between the voltage and the current is less than 0 ℃ is qualified.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and additions can be made without departing from the method of the present invention, and these modifications and additions should also be regarded as the protection scope of the present invention.
Claims (6)
1. A power flow analyzer of an electric power system is characterized by comprising a data acquisition module, a current regulation module and an analysis module,
the data acquisition module is used for acquiring voltage information and current information of a line in the power system and generating a voltage acquisition signal and a current acquisition signal;
the current adjusting module comprises a first current transformer and an adjusting unit, the secondary side of the first current transformer is connected with the current collecting signal, and the primary side of the first current transformer generates a current adjusting signal; the adjusting unit is used for adjusting the number of turns of a secondary side winding coil of the first current transformer participating in work and ensuring that the current value of the current adjusting signal is not lower than a minimum detection current threshold value;
the analysis module is used for carrying out power flow analysis according to the voltage acquisition signal and the current regulation signal.
2. The power flow analyzer of claim 1, wherein the data acquisition module is configured to acquire three-phase current information and three-phase voltage information of a line in a power system, the generated current acquisition signals include an a-phase acquisition current, a B-phase acquisition current, and a C-phase acquisition current, and the generated voltage acquisition signals include an a-phase acquisition voltage, a B-phase acquisition voltage, and a C-phase acquisition voltage;
the current regulation module is provided with three first current transformers which are used for amplifying the A-phase collected current, the B-phase collected current and the C-phase collected current by X times and then using the amplified currents as the current regulation signals, wherein X is a real number not less than 1.
3. The power system flow analyzer of claim 2, wherein the data acquisition module includes an a-phase current output interface, a B-phase current output interface, a C-phase current output interface, and a common-end current output interface, a current between the a-phase current output interface and the common-end current output interface is the a-phase acquisition current, a current between the B-phase current output interface and the common-end current output interface is the B-phase acquisition current, and a current between the C-phase current output interface and the common-end current output interface is the C-phase acquisition current;
one end of a secondary side winding coil of the three first current transformers is respectively connected with the phase-A current output interface, the phase-B current output interface and the phase-C current output interface; m selection ports which are connected outwards are respectively arranged at different positions on a secondary side winding coil of each first current transformer, the M selection ports on each first current transformer correspond to the positions of the M selection ports on the coils of the other two current transformers, and M is a positive integer which is larger than 1; and the adjusting unit selects three selection ports at the same position on the secondary side winding coils of the three first current transformers each time to be connected with the common-end current output interface.
4. The power system power flow analyzer of claim 1, wherein the data acquisition module comprises a voltage transformer and a second current transformer, a primary side of the voltage transformer is connected to a voltage signal of a line in the power system, and a secondary side of the voltage transformer generates the voltage acquisition signal; the primary side of the second current transformer is connected with a current signal of a line in a power system, and the secondary side of the second current transformer generates the current acquisition signal.
5. The power system flow analyzer of claim 1, wherein the analysis module is a single chip microcomputer.
6. The power system power flow analyzer of claim 1, further comprising a display screen for displaying a current value including the current adjustment signal and a result obtained by the analysis module after power flow analysis.
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| CN117039952A (en) * | 2023-07-17 | 2023-11-10 | 中国电建集团重庆工程有限公司 | Solar photovoltaic heat poly-generation system based on nanofluid |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117039952A (en) * | 2023-07-17 | 2023-11-10 | 中国电建集团重庆工程有限公司 | Solar photovoltaic heat poly-generation system based on nanofluid |
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