Power distribution switching control cold switching uninterruptible power switching device and method

Abstract

The invention discloses a power distribution switching control cold switching uninterruptible power switching device and method, belongs to a power distribution switching control technology, and realizes uninterruptible power in a cold switching process and accurate control of switching time. The cold switching uninterruptible power switching device comprises a sensing module, a decision module and an execution module. The sensing module obtains a main supply bus voltage Umain, a standby bus voltage Ustandby, a main supply current Imain and a switch position state S in real time. The decision-making module triggers opening and switching operations of the execution module according to a cold switching triggering condition, and the decision-making module is provided with hard interlocking logic; the execution module controls the opening / closing instruction time sequence.

Description

Technical Field

[0001] This invention belongs to the field of power engineering technology, specifically relating to power distribution switching control technology. Background Technology

[0002] Switching is the process of switching electrical equipment between operating, standby, and maintenance states in a power system, which is achieved by operating disconnect switches and circuit breakers. Traditional switching operations require manual on-site execution, which is time-consuming, labor-intensive, and poses safety risks. To achieve uninterrupted power supply during cold switching, the cold switching action time needs to be controlled. The core requirements for cold switching operations are shock-free, highly reliable, and ultra-fast (<100ms) power / bus switching, which requires overcoming three major bottlenecks: sampling delay, decision-making time, and switch execution timing. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the technical problem to be solved by this invention is to provide a power distribution switching control device and method for uninterrupted power switching during cold switching, so as to achieve uninterrupted power supply during the cold switching process and precise control of the switching time.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] First, a power distribution switching control cold-switching uninterrupted switching device is provided, including a sensing module, a decision module, and an execution module.

[0006] The sensing module acquires the main power bus voltage U in real time. main Backup bus voltage U standby Main supply current I main Switch position status S;

[0007] The decision module triggers the tripping and switching operations of the execution module according to the cold tripping trigger condition, and the decision module is equipped with hard interlock logic;

[0008] The execution module controls the timing of the opening / closing commands;

[0009] The total time T for the cold pouring operation total The sampling delay T of the sensing module is less than 100ms. sense The decision delay T of the decision module is less than 10ms. decision <5ms, the switching execution delay T of the execution module execute <85ms.

[0010] Preferably, the sampling frequency of the sensing module is f. s = 5kHz, sampling interval T s = 200μ S .

[0011] Preferably, the sensing module employs a GPS-based second pulse synchronization mechanism to ensure that the multi-loop sampling time deviation is < 10μs.

[0012] Preferably, the sampling algorithm of the sensing module uses a sliding DFT to update the fundamental parameters in real time through a recursive formula; and / or, the sampling algorithm of the sensing module uses a Kalman filter to smooth the state values.

[0013] Preferably, the cold-down triggering conditions of the decision module are as follows:

[0014] Define trigger signal 1 = Triggered, 0 = Not triggered. Triggered when all of the following conditions are met:

[0015] Where parameters The main power supply bus undervoltage threshold. The qualified threshold for the spare busbar. The fault current threshold, Duration of main supply pressure loss Main power supply / standby switch status: 1 = closed, 0 = open.

[0016] Preferably, the hard interlock logic sets an interlock signal. 1 = Allow closing, 0 = Prohibit closing:

[0017] in:

[0018] : The time when the main power supply trip command is issued;

[0019] : Actual opening time of the main power supply switch;

[0020] Current time.

[0021] Preferably, the sensing module uses an FPGA for sampling, the decision module uses an MCU for processing, and the FPGA of the sensing module and the MCU of the decision module communicate via an AXI bus.

[0022] Preferably, the switching of the execution module learns the actual action time through historical operation data, as shown in the following formula:

[0023] Parameter description:

[0024] : The actual time for opening / closing the circuit breaker during the nth operation;

[0025] Smoothing coefficient (0.8~0.9) to avoid the influence of single outliers;

[0026] Feedback time for open / closed position;

[0027] : Time when the opening / closing command is issued.

[0028] Preferably, the closing command of the execution module is sent in a predictive manner:

[0029] Closing command sending time: ;

[0030] in This is the deviation compensation time.

[0031] In addition, a method for cold-switching switching control without power interruption is provided, which is implemented using the aforementioned distribution switching control cold-switching without power interruption switching device. First, the sensing module acquires the main supply bus voltage Umain, the standby bus voltage Upaby, the main supply current Imain, and the switch position status S in real time. Then, the decision module triggers the execution module to perform opening and switching operations according to the cold-switching trigger conditions. Finally, the execution module controls the timing of the opening / closing commands.

[0032] The present invention, by adopting the above technical solution, has the following beneficial effects:

[0033] The power distribution switching control cold-switching uninterruptible switching device of this invention adopts a three-layer architecture, in which the sensing module can realize high-frequency sensing and control the sampling delay T. sense <10ms; the decision module adopts pre-fixed logic + hard interlocking to avoid complex calculation time consumption, controlling the decision delay Tdecision <5ms; the execution module implements adaptive timing control, and its switching execution delay T execute <85ms. Furthermore, combined with hardware acceleration (FPGA+MCU), precise control of the switching time is achieved. Therefore, the cold-sinking operation time can be stably controlled within 80~95ms, while meeting the requirements of "no impact and prevention of false operation", and adapting to the automation control needs of power distribution flexible self-healing devices.

[0034] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and accompanying drawings. Attached Figure Description

[0035] The invention will be further described below with reference to the accompanying drawings:

[0036] Figure 1 This is a flowchart of a power distribution switching control method for cold switching without power interruption according to the present invention. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present invention and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present invention.

[0038] Those skilled in the art will understand that, without conflict, the features in the following embodiments and implementations can be combined with each other.

[0039] This invention provides a power distribution switching control device for uninterrupted switching during cold switching, comprising a sensing module, a decision-making module, and an execution module. To achieve uninterrupted power supply during cold switching, the cold switching action time needs to be controlled within 100ms. The core requirements for cold switching operation are impact-free, highly reliable, and ultra-fast (<100ms) power / bus switching, which requires overcoming three major bottlenecks: sampling delay, decision-making time, and switch execution timing. This invention adopts a three-layer architecture of "high-frequency sensing - pre-decision - adaptive execution," combining hardware acceleration (FPGA+MCU) and software optimization, and achieves precise control of switching time through quantization formulas.

[0040] The sensing module acquires the main power bus voltage U in real time. main Backup bus voltage U standby Main supply current I main The decision module triggers the opening and switching operations of the execution module based on the cold switching trigger condition, and the decision module is equipped with hard interlock logic; the execution module controls the timing of the opening / closing commands. Additionally, a method for uninterrupted switching during cold switching in distribution control is also provided, such as... Figure 1 As shown, the cold switching without power interruption switching device described above is used for power distribution switching control.

[0041] Core objective: Total cold pouring operation time T total <100ms (from “trigger condition met” to “standby switch closing completed”).

[0042] Key constraints:

[0043] The sampling delay T of the sensing module sense <10ms, to avoid missing window switching;

[0044] The decision delay T of the decision module decision <5ms, reducing the time spent on logical judgments;

[0045] The switching execution delay T of the execution module execute<85ms, matching the mechanical characteristics of high-voltage switches, typically opening 30~50ms and closing 40~60ms.

[0046] To prevent accidental operation: the "main power disconnection → backup closing" interlock must be met to avoid circulating current / short circuit.

[0047] The sensing module is used to achieve high-frequency synchronous sampling and state calculation. The core is to reduce latency through "high-frequency sampling + hardware accelerated calculation".

[0048] High-frequency synchronous sampling design:

[0049] Sampling frequency: f s = 5kHz, sampling interval (T) s = 200μ S One fundamental frequency cycle (50Hz) contains 100 sampling points, balancing accuracy and real-time performance;

[0050] Sampling objects: Main supply / standby bus line voltage (10kV system stepped down to 0~100V by PT), main supply line current (stepped down to 0~5A by CT).

[0051] Synchronization mechanism: GPS pulse-per-second (PPS) synchronization ensures that the sampling time deviation of multiple loops is < 10μs.

[0052] Sliding DFT (SDFT) state calculation (FPGA hardware implementation):

[0053] Traditional DFT requires one fundamental cycle (20ms) to complete the calculation, which cannot meet the 10ms perceived latency requirement; sliding DFT updates the fundamental parameters in real time through a recursive formula, reducing the amount of calculation by 90%, making it suitable for hardware acceleration.

[0054] Fundamental voltage / current amplitude calculation:

[0055] For a discrete sampled sequence x(n) (where n is the sampling time), the recursive formula for the DFT coefficients of the fundamental frequency (50Hz) is: X1(n) = X1(n-1) + x(n) - x(nN) where:

[0056] ① X1(n): Fundamental DFT coefficients (complex numbers) at time n;

[0057] ② N = f s / f0 = 5000 / 50 = 100 (number of sampling points in 1 fundamental cycle);

[0058] ③ x(n): Sample value at time n; x1

[0059] ④ x(nN): Sampled value one fundamental cycle ago (old data is removed by sliding window).

[0060] Calculation of the fundamental voltage RMS value (the same applies to the current): U rms (n) = Where |X1(n) = (Modulus of DFT coefficients) This is the conversion factor from amplitude to effective value.

[0061] Fundamental frequency calculation (phase difference method):

[0062] Fundamental phase (Argument of the DFT coefficients), the frequency is derived from the rate of phase change: in T represents the phase difference between adjacent sampling times. S = 200 The sampling interval is denoted as .

[0063] Kalman filtering for noise reduction (reducing false positives):

[0064] The sampled signal is affected by electromagnetic interference and needs to be smoothed using a Kalman filter to refine the state values. Define the state vector. ,but:

[0065] State equations (voltage / frequency approximately constant over short time): in (Identity matrix) For process noise (covariance) .

[0066] Observation equation (observations are calculated using SDFT): in (Observation matrix) For observation noise (covariance) .

[0067] Kalman gain and state update:

[0068] Kalman gain:

[0069] State estimation:

[0070] Covariance update:

[0071] Final output filtered voltage ,frequency .

[0072] The decision-making module needs to quickly determine "whether a cold-down is triggered." It employs pre-fixed logic and hard interlocks to avoid complex and time-consuming calculations. The core of this module is "undervoltage criterion + voltage compliance criterion + current fault-free criterion + switch status interlock." The cold-down triggering conditions for the decision-making module are as follows:

[0073] Define trigger signal 1 = Triggered, 0 = Not triggered. Triggered when all of the following conditions are met:

[0074] Parameter definitions:

[0075] parameter meaning Typical value in accordance with Main bus undervoltage threshold GB 50053-2013 "Design Code for 20kV and Below Substations" Spare bus pass threshold Ensure stable backup power supply voltage Fault current threshold For cold-load switching (no load / light load switching), the current needs to be low. Duration of main power supply failure ≥2 sampling periods (400μs) Filter out instantaneous voltage fluctuations (such as those caused by lightning strikes). Main / Standby switch status 1 = Closed, 0 = Open Switch auxiliary contact feedback

[0076] Hard interlock logic (to prevent malfunction): To avoid short circuits caused by "main power supply not disconnected, backup power supply already closed", the hard interlock logic sets an interlock signal. 1 = Allow closing, 0 = Prohibit closing:

[0077] in:

[0078] : The time when the main power supply trip command is issued;

[0079] Actual opening time of the main power supply switch (historical learning value, including mechanical action + feedback delay);

[0080] Current time.

[0081] The core of the execution module is to accurately control the timing of the opening / closing commands to avoid "closing before opening is completed" (short circuit risk) or "excessive delay in closing after opening" (timeout risk). It needs to be adaptively adjusted in combination with the mechanical characteristics of the switch.

[0082] Adaptive learning of switching action time:

[0083] The opening and closing times of different switches vary (e.g., the opening time of the domestic VS1 switch is 25~35ms and the closing time is 35~45ms).

[0084] The switching on / off state of the execution module learns the actual action time from historical operation data, using the following formula:

[0085] Parameter description:

[0086] : The actual time for opening / closing the circuit breaker during the nth operation;

[0087] Smoothing coefficient (0.8~0.9) to avoid the influence of single outliers;

[0088] : Open / Close position feedback time (switch auxiliary contact action time);

[0089] : Time when the opening / closing command is issued.

[0090] Calculation of timing for opening and closing commands:

[0091] The cold-shutdown operation sequence is "send opening command → confirm opening completion → send closing command → confirm closing completion". To compress the total time, the closing command adopts "predictive sending" (sending the opening time in advance based on learning, rather than waiting for feedback):

[0092] Time of sending tripping command: (Time when the trigger signal is generated).

[0093] Closing command sending time: ;

[0094] in The deviation compensation time (2~5ms) is used to offset the "command transmission delay" and "switch action time fluctuation" to ensure that the closing action starts immediately after the mechanical action of opening is completed.

[0095] Total switchover time verification and adjustment:

[0096] The total cooling time is defined as "trigger time → standby switch closing feedback time", and the formula is as follows: (Reserving 5ms redundancy), the next operation will adjust accordingly: Ensure the total time is consistently < 100ms.

[0097] To meet the 100ms time constraint, the algorithm requires hardware acceleration. Recommended architecture:

[0098] FPGA: Responsible for high-frequency sampling (5kHz), sliding DFT calculation, and Kalman filtering (parallel hardware circuit calculation, delay < 1ms);

[0099] MCU (such as ARM Cortex-M7): responsible for decision-making logic, timing control, and sending of switching instructions (main frequency ≥ 200MHz, instruction cycle < 5ns, decision delay < 3ms);

[0100] Communication interface: The FPGA and MCU communicate via AXI bus (speed ≥ 1Gbps, delay < 1μs), and the switching command is transmitted via optical fiber (anti-interference, delay < 1ms).

[0101] Verification and optimization directions

[0102] Time decomposition verification: Sensing layer (10ms) + Decision layer (5ms) + Execution layer (opening 30ms + closing 45ms - deviation compensation 5ms = 70ms) = Total time 85ms < 100ms, which meets the requirements.

[0103] Understandably, the time can be shortened through further optimization. Optimization directions include:

[0104] Using faster switching (such as vacuum circuit breaker opening < 20ms, closing < 30ms), the execution layer delay can be compressed to 50ms, and the total time < 65ms;

[0105] Add a "fault retry mechanism": If the opening / closing timeout occurs (e.g., no feedback after 40ms of opening), immediately trigger the backup plan (e.g., switch to another set of backup switches).

[0106] The above algorithm can achieve a stable control of the cold-fall operation time within 80~95ms, while meeting the requirements of "no impact and prevention of malfunction", and adapting to the automation control needs of the power distribution flexible self-healing device.

[0107] The above description is merely a specific embodiment of the invention, but the scope of protection of the invention is not limited thereto. Those skilled in the art should understand that the invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of the invention will be included within the scope of the claims.

Claims

1. A power distribution switching control cold-switching uninterrupted switching device, characterized in that, It includes a perception module, a decision-making module, and an execution module. The sensing module acquires the main power bus voltage U in real time. main Backup bus voltage U standby Main supply current I main Switch position status S; The decision module triggers the tripping and switching operations of the execution module according to the cold tripping trigger condition, and the decision module is equipped with hard interlock logic; The execution module controls the timing of the opening / closing commands; The total time T for the cold pouring operation total The sampling delay T of the sensing module is less than 100ms. sense The decision delay T of the decision module is less than 10ms. decision <5ms, the switching execution delay T of the execution module execute <85ms.

2. The power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The sampling frequency of the sensing module is f s = 5kHz, sampling interval T s = 200μ S .

3. The power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The sensing module employs a GPS-based second pulse synchronization mechanism to ensure that the sampling time deviation of multiple loops is less than 10μs.

4. The power distribution switching control cold switching uninterruptible switching device according to claim 1, characterized in that, The sampling algorithm of the sensing module uses a sliding DFT to update the fundamental parameters in real time through a recursive formula; and / or, the sampling algorithm of the sensing module uses a Kalman filter to smooth the state values.

5. A power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The cold-down trigger conditions for the decision module are as follows: Define trigger signal 1 = Triggered, 0 = Not triggered. Triggered when all of the following conditions are met: Where parameters The main power supply bus undervoltage threshold. The qualified threshold for the spare busbar. The fault current threshold, Duration of main supply pressure loss Main power supply / standby switch status: 1 = closed, 0 = open.

6. A power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The hard interlock logic sets the interlock signal. 1 = Allow closing, 0 = Prohibit closing: in: : The time when the main power supply trip command is issued; : Actual opening time of the main power supply switch; Current time.

7. A power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The sensing module uses an FPGA for sampling, and the decision module uses an MCU for processing. The FPGA of the sensing module and the MCU of the decision module communicate via an AXI bus.

8. A power distribution switching control cold-switching uninterruptible switching device according to claim 1, characterized in that, The switching on / off state of the execution module learns the actual action time from historical operation data, using the following formula: Parameter description: : The actual time for opening / closing the circuit breaker during the nth operation; Smoothing coefficient (0.8~0.9) to avoid the influence of single outliers; Feedback time for open / closed position; : Time when the opening / closing command is issued.

9. A power distribution switching control cold-switching uninterruptible switching device according to claim 8, characterized in that, The closing command of the execution module is sent in a predictive manner: Closing command sending time: ; in This is the deviation compensation time.

10. A method for cold switching without power interruption in power distribution switching control, characterized in that, The distribution switching control cold switching uninterruptible switching device according to any one of claims 1 to 9 is implemented as follows: First, the sensing module acquires the main supply bus voltage Umain, the standby bus voltage Upaby, the main supply current Imain, and the switch position status S in real time; then, the decision module triggers the execution module to perform opening and switching operations according to the cold switching triggering conditions; finally, the execution module controls the timing of the opening / closing commands.

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