Phase selection closing device based on arc extinguishing point residual magnetism algorithm
Through the arc extinguishing point remanent magnetism algorithm and the adaptive split-closing compensation algorithm, the problem of excessive surge flow caused by controlling the closing angle of the phase-selection closing device is solved, and more accurate remanent magnetism calculation and split-closing time compensation are achieved, which improves the The operation success rate of the transformer.
Patent Information
- Application Number
- CN202420659989.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-01
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-04-01
AI Technical Summary
The existing phase-selecting closing device can easily cause excessive inrush of the transformer when controlling the closing angle, resulting in the problem of failure of the transformer operation.
The arc-extinguishing point residual magnetization algorithm is adopted to collect the three-phase voltage and current signals on the transformer side in real time, combine the environmental data of the circuit breaker, and use the main control plug-in board of the multi-device combination architecture for logic control and analog processing to achieve accurate Residual magnetic calculation and adaptive closing compensation reduce inrush current.
The control accuracy of the phase-selecting and closing device is improved, the inrush current is suppressed within the ideal range, and the operation success rate of the transformer is enhanced.
Smart Images
Figure CN222147158U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of transformers, in particular to a phase selection and closing device based on an arc extinction point residual magnetism algorithm. Background Art
[0002] The transformer in the primary equipment of the power system is a nonlinear load. When performing live switching operations, a transient process of large-scale operating overvoltage or closing inrush current will randomly occur, resulting in abnormal operating conditions such as protection tripping, system voltage fluctuations, and a large amount of harmonic pollution, which will have a significant impact on the safe operation of the power system.
[0003] There are generally two types of existing technologies. One is a direct control method, which controls the opening of the switch at 90° and the closing of the switch at 90° to achieve the suppression of the opening overvoltage and the closing inrush current. The essence of this method is to control the opening residual magnetism to 0 and the closing bias magnetism to 0, so that the total magnetic flux value at the moment of closing is small and not greater than the saturation magnetic flux, thereby achieving the suppression of the inrush current. However, this method assumes that the transient process of the three phases after the opening is consistent and maintains a symmetrical state. The actual inrush current suppression effect is closely related to the opening transient process of the three phases. Another residual magnetism calculation control method calculates the residual magnetism value through the voltage integration method, calculates the optimal closing angle through the inrush current generation mechanism, and achieves the mutual cancellation of the magnetic flux by accurately controlling the closing angle. Theoretically, both of the above-mentioned methods can reduce the probability of magnetic flux saturation to achieve the effect of suppressing overvoltage and inrush current. However, in actual engineering applications, the performance parameters of the circuit breaker controlled by the phase-selective closing device are often not consistent. There is a time error of about 1ms or even 2ms in its opening and closing time (under the power frequency, the angle error caused by 1ms is 18°). Moreover, the mechanical time of the auxiliary contacts and the main contacts cannot truly reflect the real-time electrical opening and closing state, which will greatly affect the control accuracy of the device and thus affect the switching effect.
[0004] Since the current mainstream residual magnetism calculation method uses the voltage integration method to calculate residual magnetism, this method only considers the voltage-flux relationship of the linear segment of the hysteresis loop during the initial modeling. After the transformer core is magnetically saturated, the flux and voltage show a nonlinear change process, which leads to a protective tripping situation when the transformer is put into operation due to magnetic saturation in actual engineering applications. The residual magnetism deviation calculated by the voltage integration method is too large, resulting in a large residual magnetism error calculated using this method. The closing device designed by this calculation method has too large an inrush current when it is closed again, and the transformer fails to be put into operation. Summary of the invention
[0005] The utility model provides a phase selection closing device with an arc extinction point residual magnetism algorithm, aiming to solve the problem that the closing angle controlled by the existing phase selection closing device easily leads to excessive inrush current of the transformer and failure of the transformer to be put into operation.
[0006] The utility model provides a phase selection closing device of an arc extinction point residual magnetism algorithm, comprising a bus board, a main control plug-in board, a compensation plug-in board for collecting non-electrical signals, an input plug-in board, an output plug-in board and a sampling plug-in board, wherein the main control plug-in board, the compensation plug-in board, the input plug-in board, the output plug-in board and the sampling plug-in board are respectively connected to the bus board, the input plug-in board is connected to a short circuit breaker, the output plug-in board is connected to an opening and closing circuit of a circuit breaker, the sampling plug-in board is connected to two ends of the circuit breaker, a CPU chip for logic control, an FPGA module for completing real-time acquisition of input and analog quantities and a DSP module for secondary processing of analog quantities are arranged in the main control plug-in board, and the FPGA module and the DSP module are respectively connected to the CPU chip.
[0007] As a further improvement of the utility model, a voltage sensor and a current sensor are provided between the sampling plug-in board and the primary circuit of the power system.
[0008] As a further improvement of the present invention, the secondary processing of analog quantity by the DSP module includes filtering, arc extinction point residual magnetism algorithm and adaptive opening and closing compensation algorithm.
[0009] As a further improvement of the present invention, the non-electrical signals collected by the compensation plug-in board include but are not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time and operating voltage.
[0010] As a further improvement of the utility model, it also includes a power plug-in board for providing a DC voltage, and the power plug-in board is connected to the bus board.
[0011] As a further improvement of the present invention, the output plug-in board includes a first output board and a second output board, both ends of the first output board and both ends of the second output board are respectively connected to the main control plug-in board and the opening and closing circuit of the circuit breaker, and the second output board is independent of the system control of the main control plug-in board.
[0012] As a further improvement of the present invention, the CPU chip is connected to a storage module.
[0013] As a further improvement of the present invention, the CPU chip is connected to a digital-to-analog conversion module.
[0014] As a further improvement of the present invention, the CPU chip is connected to a communication module.
[0015] As a further improvement of the present invention, the CPU chip is connected to a human-computer interaction module, and the human-computer interaction module includes a display for displaying information, buttons for operation, and an indicator light for displaying a working status.
[0016] The beneficial effect of the utility model is: with the help of the above-mentioned hardware platform and a more advanced arc extinction point residual magnetism algorithm, the residual magnetism remaining in the transformer core after opening and the optimal closing angle for the next closing can be calculated more accurately, and then by monitoring the environmental data of the circuit breaker, the opening and closing time can be adaptively compensated, the transformer inrush current can be suppressed within an ideal range, and the applicable working condition range of the phase selection closing device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a schematic diagram of the connection between the modules of the device of the utility model;
[0018] Figure 2 This is a schematic diagram of the main control plug-in board architecture of the utility model;
[0019] Figure 3 It is a connection diagram of engineering application of the device of the utility model. DETAILED DESCRIPTION
[0020] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.
[0021] like Figure 1-3 As shown, the utility model provides a phase selection and closing device based on the arc extinction point residual magnetism algorithm, including a bus board, a main control plug-in board, a compensation plug-in board for collecting non-electrical signals, an input plug-in board, an output plug-in board and a sampling plug-in board, the main control plug-in board, the compensation plug-in board, the input plug-in board, the output plug-in board and the sampling plug-in board are respectively connected to the bus board, the input plug-in board is connected to the short circuiter, the output plug-in board is connected to the opening and closing circuit of the circuit breaker, the sampling plug-in board is connected to both ends of the circuit breaker, the main control plug-in board is provided with a CPU chip for logic control, an FPGA module for completing real-time acquisition of input and analog quantities, and a DSP module for secondary processing of analog quantities, and the FPGA module and the DSP module are respectively connected to the CPU chip.
[0022] As an embodiment of the utility model, a voltage sensor and a current sensor are provided between the sampling plug-in board and the primary circuit of the power system.
[0023] As another embodiment of the utility model, the secondary processing of analog quantity by the DSP module includes filtering, arc extinction point residual magnetism algorithm and adaptive opening and closing compensation algorithm.
[0024] As another embodiment of the utility model, the non-electrical signals collected by the compensation plug-in board include but are not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time and operating voltage.
[0025] As another embodiment of the utility model, it further includes a power plug-in board for providing a DC voltage, and the power plug-in board is connected to the bus board.
[0026] As another embodiment of the utility model, the output plug-in board includes a first output board and a second output board, both ends of the first output board and both ends of the second output board are respectively connected to the main control plug-in board and the opening and closing circuit of the circuit breaker, and the second output board is independent of the system control of the main control plug-in board.
[0027] As another embodiment of the present utility model, the CPU chip is connected to a storage module.
[0028] As another embodiment of the present utility model, the CPU chip is connected to a digital-to-analog conversion module.
[0029] As another embodiment of the present utility model, the CPU chip is connected to a communication module.
[0030] As another embodiment of the present utility model, the CPU chip is connected to a human-computer interaction module, and the human-computer interaction module includes a display for displaying information, buttons for operation, and an indicator light for displaying a working status.
[0031] The utility model provides a phase-selective closing device based on the arc extinction point residual magnetism algorithm. In order to solve the transient switching influence of primary nonlinear equipment from the source, a phase-selective closing device applied to transient switching phase control is designed. This device belongs to the category of secondary equipment, and is designed with the function of phase separation and linkage control of switching timing, that is, by controlling the circuit breaker to open and close at a specified angle, the transient influence of the switching of the above-mentioned nonlinear load is reduced. In addition, the device is designed with a variety of control circuit breaker operation time correction algorithms to ensure the reliability and stability of actual control. The device adopts different control strategies for different types of circuit breakers and different types of load characteristics, and realizes the control of opening overvoltage and closing inrush current by conveniently and flexibly setting control parameters and constants.
[0032] The phase selection and closing device designed in this device is realized by a combination of multiple plug-in boards. The realization of the arc extinction point residual magnetism algorithm requires real-time collection of the three-phase voltage signal and three-phase current signal on the transformer side at the time of opening. When the transformer is put into operation, it is necessary to collect the three-phase voltage signal on the power supply side before and after the closing time in real time. The compensation board mainly collects non-electrical data that may affect the performance of the circuit breaker, including but not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time, operating voltage and other data. The collection of these data is converted into analog quantity by various physical quantity collection sensors, and then converted into digital quantity input device through AD to compensate for the opening and closing time through adaptive compensation algorithm. The device realizes the collection of analog quantity required by the arc extinction point residual magnetism algorithm through the sampling plug-in board. At the same time, in order to meet the real-time performance and smooth implementation of the algorithm, the main control plug-in board is implemented with a multi-device combination architecture.
[0033] The functions of each plug-in and the signal acquisition and processing are as follows:
[0034] In addition to receiving the opening and closing start command from the local or system console to start the device, the plug-in board also needs to collect the position status information of the circuit breaker to assist in determining the actual position of the circuit breaker.
[0035] The first output board, after the arc extinction point residual magnetism algorithm is calculated inside the device, outputs the opening and closing command from the first output board to the opening and closing circuit in the circuit breaker operation box, realizing the phase selection control of the circuit breaker opening and closing. In order to ensure accuracy and speed, and meet the requirements of large capacity of the opening and closing circuit, the first output board adopts power electronic devices to achieve accurate and fast output.
[0036] The second output board is used in conjunction with the first output board to meet the requirement that there is no mechanical break in the opening and closing circuit. It is also a measure to increase the prevention of false operation. The second output board has a system control independent of the main control plug-in board to prevent the circuit breaker from false operation under abnormal conditions of the main control.
[0037] The sampling plug-in board receives the three-phase AC voltage and current from both sides of the circuit breaker. The front-end voltage of the circuit breaker is used as a reference for phase selection control, and the rear-end voltage is used as a reference for transformer residual magnetism calculation and circuit breaker action time. The current is mainly used to calculate the size of the inrush current to display the switching effect in real time. The line current is basically zero before the circuit breaker is closed at no load, but when the transformer is closed at no load, the size of the closing current can be used as a basis for judging the inrush current suppression effect. The AC voltage and AC current here are high-voltage signals in the primary system, which need to be converted by the voltage transformer and the current transformer before being input into the sampling plug-in board.
[0038] The main control plug-in board, the control core of the device, completes the acquisition of analog quantity and input data, calculates residual magnetism through the arc extinction point residual magnetism algorithm, and then compensates the closing time through the adaptive opening and closing compensation algorithm, and then performs phase selection control calculation, and issues the opening and closing control command at a predetermined time. In addition, the main control plug-in board records the working records and sampled data of the device, such as the state change of the input quantity, the modification information of the fixed value parameters, the opening and closing outlet control events and action recording records. The architecture of the main control plug-in board is composed of CPU+DSP+FPGA. The FPGA module mainly completes the real-time acquisition of the input and analog quantity, the DSP module realizes the secondary processing of the analog quantity transmitted by the transformer plug-in board (filtering, arc extinction point residual magnetism algorithm, adaptive opening and closing compensation algorithm, etc.), and the CPU chip realizes logic control, communication and human-computer interaction, and precise control of the outlet signal.
[0039] The power plug-in board is connected to the external working power supply and converted into multiple levels of DC voltage used by the internal components of the device.
[0040] The compensation plug-in board is mainly used to collect signals sent by various sensors that monitor the circuit breaker, including but not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time, operating voltage and other data. The collection of these physical quantity data is converted into analog quantity through various acquisition sensors, and then converted into digital quantity through AD and input into the compensation board. The compensation board compensates for the opening and closing time through the adaptive compensation algorithm, and further optimizes the control circuit breaker action time to achieve better control effect.
[0041] The human-machine interaction module, the front panel of the device, is designed with a display, buttons and indicator lights for human-machine interaction operations. It can display in real time the size of each calculated residual magnetism, the size of the closing inrush current, polarity, inrush current multiples and other related information.
[0042] Spare plug-in board, reserved expansion board to suit different working conditions.
[0043] Engineering application implementation process: The phase selection closing device is powered on, the circuit breaker is in the open position, and the transformer is not connected to the power grid system. The phase selection closing device collects the grid side voltage through the voltage transformer, calculates the optimal closing angle according to the residual magnetism method calculated by the arc extinction point algorithm when opening, and compensates the opening and closing time through the closing time adaptive compensation algorithm. After receiving the closing command sent by the system control background, the circuit breaker is controlled to close at the expected voltage angle, so that the transformer is connected to the power grid system and the inrush current suppression closing operation of the transformer is realized. During the entire operation process of the phase selection closing device, no human intervention is required, and the opening and closing angles do not need to be set in advance. The device automatically calculates the next closing angle through the voltage and current data of the transformer end collected during the last opening process, and uses the arc extinction point residual magnetism algorithm, and then calculates the compensation amount of the opening and closing time through the environmental data of the circuit breaker (including but not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time, operating voltage and other data). The engineering application connection diagram is as follows Figure 3 .
[0044] Affected by the stability of the current circuit breaker, the switching effect of the phase-selective closing device mainly depends on the performance of the circuit breaker. In order to reduce the inhibitory effect of the circuit breaker dispersion on the closing excitation inrush current, the overvoltage inrush current is fundamentally suppressed by flux cancellation. This device improves the residual magnetism calculation accuracy through appropriate hardware configuration and the arc extinction point residual magnetism algorithm of the software, and then automatically calculates the opening and closing time through the collected voltage data. By collecting the circuit breaker environmental variables, the opening and closing adaptive compensation algorithm is used to compensate the circuit breaker opening and closing time according to the environmental variables, which will minimize the impact on the circuit breaker performance. From the perspective of practical engineering applications, the optimal closing angle can be accurately controlled, and the effect of suppressing the inrush current can be improved from the residual magnetism calculation and control accuracy.
[0045] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.
Claims
1. A phase selection closing device based on arc extinction point residual magnetism algorithm, characterized in that: It comprises a bus board, a main control plug-in board, a compensation plug-in board for collecting non-electrical signals, an input plug-in board, an output plug-in board and a sampling plug-in board. The main control plug-in board, the compensation plug-in board, the input plug-in board, the output plug-in board and the sampling plug-in board are respectively connected to the bus board, the input plug-in board is connected to the short circuiter, the output plug-in board is connected to the opening and closing circuit of the circuit breaker, and the sampling plug-in board is connected to both ends of the circuit breaker. The main control plug-in board is provided with a CPU chip for logic control, an FPGA module for completing the real-time acquisition of the input and analog quantity, and a DSP module for the secondary processing of the analog quantity. The FPGA module and the DSP module are respectively connected to the CPU chip.
2. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: A voltage sensor and a current sensor are arranged between the sampling plug-in board and the primary circuit of the power system.
3. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: The secondary processing of analog quantity by the DSP module includes filtering, arc extinction point residual magnetism algorithm and adaptive opening and closing compensation algorithm.
4. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: The non-electrical signals collected by the compensation plug-in board include but are not limited to temperature, SF6 gas pressure, operating oil pressure, number of actions, action time, interval time and operating voltage.
5. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: It also includes a power plug-in board for providing a DC voltage, and the power plug-in board is connected to the bus board.
6. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: The output plug-in board includes a first output board and a second output board. Both ends of the first output board and both ends of the second output board are respectively connected to the main control plug-in board and the opening and closing circuit of the circuit breaker. The second output board is independent of the system control of the main control plug-in board.
7. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: The CPU chip is connected to the storage module.
8. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1 is characterized in that: The CPU chip is connected to the digital-to-analog conversion module.
9. The phase selection closing device based on the arc extinction point residual magnetism algorithm according to claim 1, characterized in that: The CPU chip is connected to the communication module.
10. The phase selection closing device based on arc extinction point residual magnetism algorithm according to claim 1, characterized in that: The CPU chip is connected to a human-computer interaction module, and the human-computer interaction module includes a display for displaying information, buttons for operation, and an indicator light for displaying a working status.