CN-121813692-B - Self-adaptive feeder coordinated control method and system for voltage-time logic power distribution network

CN121813692BCN 121813692 BCN121813692 BCN 121813692BCN-121813692-B

Abstract

The invention relates to the technical field of feeder automation of a power distribution system, and discloses a self-adaptive feeder coordinated control method and a self-adaptive feeder coordinated control system of a voltage-time logic power distribution network, wherein the method comprises the steps of calculating an equivalent attenuation time constant by means of fitting by capturing a voltage loss attenuation discrete sequence in a line loss process so as to generate a load impedance inertia index; the method comprises the steps of calculating the space occupation width of time slot bubbles on a reference recovery time axis, generating a self-adaptive delay increment, superposing a discretization dithering factor to obtain a target access time threshold, monitoring a line incoming side bus voltage sinking event in real time by using a timing integrator, synthesizing a congestion warning signal, performing freezing and thawing operation on the integrator according to the congestion degree, and sending an access driving pulse only when an accumulated effective time integral value reaches the target access time threshold.

Inventors

LI WEI
ZHU ZHILIANG
WANG XIAOYANG
YANG PENG
KANG YANRONG
HAN YAO
Bai Shuangyin
ZHU CHUN
MA XIN

Assignees

内蒙古电力(集团)有限责任公司鄂尔多斯供电分公司

Dates

Publication Date: 20260505
Application Date: 20260309

Claims (8)

1. The self-adaptive feeder coordination control method for the voltage-time logic power distribution network is characterized by comprising the following steps of: Capturing a voltage loss attenuation discrete sequence in the line voltage loss process, fitting the voltage loss attenuation discrete sequence, calculating an equivalent attenuation time constant, and generating a load impedance inertia index according to the equivalent attenuation time constant; Defining a reference recovery time axis, calculating the space occupation width of the time slot bubbles on the reference recovery time axis according to the load impedance inertia index, wherein the larger the load impedance inertia index is, the wider the space occupation width of the time slot bubbles is; Starting a timing integrator, monitoring a voltage sag event of a bus at the wire inlet side in real time in the running process of the timing integrator, extracting a voltage sag depth and a voltage sag duration, weighting the voltage sag depth and the voltage sag duration to synthesize a congestion warning signal, respectively executing time integral freezing and thawing operations on the timing integrator according to the congestion warning signal, and sending an access driving pulse when a time integral value accumulated by the timing integrator reaches a target access time threshold; The starting condition of the timing integrator is that when the feeder terminal detects a single-side voltage recovery event, the voltage waveform of the bus at the wire inlet side is monitored in real time, whether the voltage of the bus at the wire inlet side is in a stable threshold range or not is confirmed, the preset starting stability confirmation time is continuously kept, if the voltage is met, the timing integrator is started, and the time integral value is initialized to be zero.
2. The method for adaptively controlling feeder coordination of a voltage-time logic power distribution network according to claim 1, wherein the line voltage loss is that the line voltage is lower than a rated voltage threshold; The method for acquiring the voltage loss attenuation discrete sequence comprises the steps of collecting a plurality of discrete data points of voltage amplitude values in a transient window when a feeder terminal detects line loss, and forming the voltage loss attenuation discrete sequence in a time sequence.
3. The method for adaptively controlling a feeder line of a voltage-time logic distribution network according to claim 2, wherein the method for calculating the equivalent decay time constant comprises: The method comprises the steps of performing curve fitting on a voltage loss attenuation discrete sequence to construct a voltage attenuation track curve, selecting an effective analysis section from the voltage attenuation track curve, calculating the average attenuation rate of voltage amplitude values in the effective analysis section, and calculating an equivalent attenuation time constant according to the average attenuation rate.
4. A voltage-time logic distribution network adaptive feeder coordinated control method according to claim 3 and wherein said load impedance inertia index is obtained by dividing a preset no-load line reference decay constant by an equivalent decay time constant.
5. The adaptive feeder coordination control method for a voltage-time logic power distribution network according to claim 4, wherein the reference recovery time axis defining method comprises: when the feeder terminal detects the one-side voltage recovery, a reference recovery time axis is defined by taking the moment when the one-side voltage recovery is detected as a zero point.
6. The self-adaptive feeder coordination control method for the voltage-time logic power distribution network according to claim 5, wherein the generation method of the discretization dithering factor comprises the steps of extracting a unique physical code of a feeder terminal, and performing hash operation on the unique physical code of the feeder terminal to generate the discretization dithering factor; the target access time threshold is obtained by adding preset basic delay, self-adaptive delay increment and discretization dithering factors.
7. The method for adaptive feeder coordination control of a voltage-time logic distribution network according to claim 6, wherein the method for performing time integral freezing and thawing operations on the timing integrator according to the congestion alert signal comprises: When the congestion warning signal exceeds a preset safety warning threshold value, executing time integration freezing operation on the timing integrator, suspending the timing integrator and keeping the current time integration value unchanged; And continuously calculating a congestion warning signal in a time integration freezing state, and executing time integration defrosting operation on a timing integrator when the congestion warning signal is lower than a preset congestion relief reset threshold and the line-in side bus voltage is kept within a preset defrosting stability confirmation time within a stability threshold range, wherein the congestion relief reset threshold is smaller than a safety warning threshold, and the timing integrator continuously accumulates from a time integral value before time integration freezing.
8. A voltage-time logic distribution network adaptive feeder coordination control system for implementing the voltage-time logic distribution network adaptive feeder coordination control method according to any one of claims 1 to 7, characterized in that the system comprises: The load inertia calculation module is used for capturing a voltage loss attenuation discrete sequence in the line voltage loss process, fitting the voltage loss attenuation discrete sequence, calculating an equivalent attenuation time constant and generating a load impedance inertia index according to the equivalent attenuation time constant; The access threshold generation module is used for defining a reference recovery time axis, calculating the space occupation width of the time slot bubble on the reference recovery time axis according to the load impedance inertia index, generating a self-adaptive delay increment according to the space occupation width of the time slot bubble, and superposing a discretization dithering factor on the self-adaptive delay increment to generate a target access time threshold; the integral access control module is used for starting the timing integrator, monitoring the voltage sag event of the bus at the incoming line side in real time in the running process of the timing integrator and synthesizing a congestion warning signal, respectively executing time integral freezing and thawing operations on the timing integrator according to the congestion warning signal, and sending an access driving pulse when the time integral value accumulated by the timing integrator reaches a target access time threshold value.

Description

Self-adaptive feeder coordinated control method and system for voltage-time logic power distribution network Technical Field The invention relates to the technical field of feeder automation of power distribution systems, in particular to a self-adaptive feeder coordination control method and system for a voltage-time logic power distribution network. Background With the rapid development of intelligent power distribution network technology, the power supply reliability has become a core index for measuring the service quality of a power system. In the embodiment of power distribution automation, the voltage-time (V-T) feeder automation mode is widely applied to the fault isolation and non-fault area restoration power supply scene of the medium-voltage distribution network because the voltage-time (V-T) feeder automation mode does not depend on a real-time communication network, has low construction cost and strong logic independence. The mode monitors the voltage state of a line through a Feeder Terminal (FTU), and realizes automatic switching and time sequence matching of the sectional switch according to preset voltage judging logic and time fixed values, so that the redistribution and the supply of electric energy are completed. In order to ensure the accuracy of such feeder terminal logic actions, various test and verification schemes have been proposed in the prior art. For example, chinese patent CN110261724B discloses a voltage time type feeder automation test method, which uses a voltage time type logic tester to control an ac voltage output interface, simulate voltage variation of a line, and collect switch position feedback, so as to determine whether the action logic of a feeder terminal under a specific voltage time sequence is correct. In addition, the chinese patent application with publication number CN112540262a discloses a voltage-time feeder automation test system and a test method thereof, and by matching the control background with a plurality of testers, control signals are sent to feeder terminals distributed on each switch of the tested line, and test cases are extracted, so that batch and sequential automatic test of a plurality of devices is realized, and test efficiency and coverage rate are improved. However, although the prior art effectively solves the problems of verification and test of functions of feeder terminal equipment, there is still a systematic power failure risk caused by mismatch between "fixed sequential logic" and "dynamic load inertia" in the practical power restoration control policy of the power distribution network. In particular, conventional voltage-time logic typically performs the switching-in operation of the sectionalizer in accordance with a pre-solidified fixed time step, e.g., X-time limit, Y-time limit. The rigid time sequence setting mode regards the feeder terminal as a simple time counter, and ignores physical characteristic differences of actual mounted loads in a power-off area, such as inductive load duty ratio, cold start power requirement and the like. During a power failure caused by voltage loss, motor loads such as an air conditioner, a compressor, a water pump and the like on a line can enter a cold state due to stopping, and the equivalent impedance of the motor loads is obviously reduced. When the upper power supply resumes the power supply, if a plurality of feeder line segments are only connected in turn according to fixed time intervals, and the cold start inertia of each segment load is not considered, a disorder stacking phenomenon is very easy to occur, namely, exciting surge current caused by the former stage heavy load segment connection is not attenuated, bus voltage is in the fragile moment of the concave recovery period, and the latter stage segment switch is connected in force under the drive of fixed delay. The lack of perceived time sequence overlapping can cause destructive vector superposition of multistage cold start inrush current on a power supply loop, so that the total current instantaneously exceeds the bearing limit of an upper power supply or a transformer substation outlet switch, the upper power supply is caused to interrupt power supply again due to overwhelming, and finally self-healing recovery failure of the whole feeder line is caused, and the stability and the continuity of the power supply capacity of a power distribution network are restricted. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a self-adaptive feeder coordinated control method and a self-adaptive feeder coordinated control system for a voltage-time logic distribution network, local load inertia is quantified by excavating the natural voltage attenuation characteristic in the voltage losing process of a line, the access time sequence of each feeder terminal is dynamically adjusted according to the local load inertia, and an integral control mechanism based on voltage sinking feedback is int