Method for positioning fault point of sliding contact line of coke oven railway vehicle

Abstract

The invention relates to a method for positioning a fault point of a sliding contact line of a coke oven railway vehicle. The method comprises the steps of setting a voltage monitoring device, normally putting the railway vehicle into production, calculating resistance, positioning the fault point and the like. The method for positioning the fault point of the sliding contact line of the coke oven railway vehicle has the function of monitoring the voltage drop of the sliding contact line in real time on line; the power supply state of the sliding contact line can be judged and fault parts can be positioned; the resistance of the slide wire can be measured and monitored; the abnormal part of the sliding contact line can be quickly and accurately positioned according to the actual production condition; abnormal conditions of a coke oven vehicle power supply system can be found in time; fault checking time is shortened, undervoltage of the vehicle caused by faults of a power supply system is avoided, and working efficiency of the vehicle is improved.

Description

Technical Field

[0001] The invention relates to a method for locating a fault point of a busbar of a coke oven rail vehicle, and belongs to the technical field of electrical equipment. Background Art

[0002] The rail vehicle of the coke oven, usually called the coke oven four-carriage, is an important process equipment in the coke oven production. Its electricity comes from the steel busbar installed on the ground, and the power supply slider on the vehicle provides production power for the coke oven rail vehicle. The busbars are connected to each other by connecting plates. Compared with ordinary mobile vehicles that draw electricity through busbars, the busbars of the coke oven four-carriage have the characteristics of long power supply distance, large load, and drastic load changes. In the prior art, on-board voltage and current monitoring equipment is generally installed on the vehicle. The power supply status of the busbar is judged by manually comparing the ground incoming line voltage meter value and the real-time power receiving voltage value of the vehicle. There are several problems in actual application: 1. The steel busbar itself has resistance, which leads to a voltage drop ΔU between the power supply head and the end of a single busbar. It is impossible to judge whether the voltage drop value is normal only by the on-board voltage and current monitoring equipment. Since the busbars of each phase of the four major coke oven cars are made of segmented busbars spliced ​​together by connecting pieces, in addition to the resistance of the steel busbar itself, there is inevitably contact resistance in the splicing process, which leads to a significant voltage drop between the head and the end of the entire power supply line even under low load conditions. The existing on-board detection technology cannot monitor these voltage drops in real time, nor can it determine whether the voltage drop range is normal.

[0003] 2. The load of the four coke oven cars changes violently, resulting in unstable power supply voltage and large fluctuations, and the cause of undervoltage is difficult to determine. Especially during the coke pushing process of the coke pushing car, the huge load current of the coke pushing motor causes a significant voltage drop on the busbar. If the busbar has intermittent abnormal contact resistance ΔR at this time, it will cause a large voltage drop. The undervoltage operation of the motor further increases the motor current, causing the busbar power supply to enter a vicious cycle state. However, the root cause of the voltage drop cannot be determined by the existing voltage and current detection methods.

[0004] 3. Unable to quickly identify the fault point of the busbar. As the busbar is vibrated by the operation of the vehicle, the loosely connected parts are prone to intermittent contact resistance, which will cause a large voltage drop in the presence of a large current. The on-board monitoring equipment can only determine that the resistance value from the busbar input line to the vehicle's electrical equipment is abnormal, but cannot confirm the specific fault location. Moreover, as the vibration disappears, the contact resistance will also disappear, making it impossible to quickly identify the fault point of the busbar. Summary of the invention

[0005] The technical problem to be solved by the present invention is: to overcome the shortcomings of the above-mentioned technology and provide a method for segmented and continuous online monitoring of the state of the busbar of a coke oven rail vehicle, which can quickly discover abnormal conditions and fault locations during the power supply of the busbar and ensure that the busbar reliably supplies power to the coke oven vehicle.

[0006] In order to solve the above technical problems, the technical solution proposed by the present invention is: a method for locating the fault point of the busbar of a coke oven rail vehicle, comprising the following steps: (1) Voltage monitoring devices are installed next to all busbars on the track; the voltage monitoring device signals are output to the monitoring system; the monitoring system reads the voltage value measured by the voltage monitoring device; the current value and position information measured by the current monitoring device in the rail vehicle are output to the monitoring system; (2) Putting rail vehicles into production according to the production plan; (3) When the rail vehicle arrives at the predetermined operating position and starts to operate, the test section is from the power connection position of the track to the current position of the rail vehicle. The voltage drop on each busbar in the test section is calculated in turn, and the resistance of each busbar is calculated based on the current value; (4) If the resistance of a busbar exceeds the threshold, the busbar is judged to be faulty.

[0007] A further improvement of the above solution is that a second rail vehicle is arranged at an operation position at the farthest end of the rail away from the power connection position of the rail, and operates to generate a detection current.

[0008] A further improvement of the above scheme is that the threshold in step (4) is (1+β)R n ; where R n is the standard resistance of the nth busbar, and β is the standard resistance bias rate.

[0009] The method for locating the fault point of the busbar of a coke oven rail vehicle provided by the present invention has the function of real-time online monitoring of the voltage drop of the busbar; can judge the power supply status of the busbar and locate the fault part; can measure and monitor the resistance of the busbar; according to the actual production situation, the abnormal part of the busbar can be quickly and accurately located; and can also timely discover the abnormal condition of the power supply system of the coke oven vehicle; shorten the fault inspection time, avoid undervoltage of the vehicle due to power supply system failure, and improve the working efficiency of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be further described below in conjunction with the accompanying drawings.

[0011] Figure 1 It is a schematic diagram of the application scenario structure of a preferred embodiment 1 of the present invention.

[0012] Figure 2 It is a schematic diagram of the structure of a monitoring device according to a preferred embodiment 1 of the present invention.

[0013] Figure 3 It is a schematic diagram of the application scenario structure of a preferred embodiment 2 of the present invention.

[0014] The numbers in the figure are as follows: 2-busbar; 3-connecting piece; 4-vehicle power supply slider; 5-voltage measurement hole; 6-phase voltage probe. Implementation

[0015] Embodiment 1: A method for locating a fault point of a busbar of a coke oven rail vehicle in this embodiment comprises the following steps: (1) Design a set of busbar monitoring equipment. The structure diagram of each device is as follows: Figure 1 As shown, the ground voltage monitoring device is installed on the ground. Each ground voltage monitoring device has three phase voltage measurement probes, which are used to measure the phase voltage of each busbar at the same geographical location, and connect to the voltage monitoring devices at other locations through bus connection. The signal line is connected to the monitoring control system to transmit the phase voltage and position signal of each busbar to the monitoring system. The vehicle current monitoring device is installed on each coke oven vehicle to collect the current of each phase entering the vehicle through the power-collecting slider during the operation of the vehicle, and transmit the signal to the busbar monitoring system through the on-board wireless communication system. The busbar monitoring system is installed on the ground, receives signals sent from the voltage monitoring device and the vehicle current monitoring device, and monitors and continuously records the phase voltage and current signal flowing through each section of the busbar in real time.

[0016] The ground voltage monitoring device is used to detect the phase voltage of the busbars at the same geographical location. A voltage detection hole is set near the position where each busbar is connected to the next busbar for power supply. The phase voltage measurement probe on the ground voltage monitoring device can be inserted into the hole to monitor the phase voltage of the busbar of this section. These voltage monitoring devices are installed on each section of the busbar of the entire power supply line. The voltage monitoring device will transmit the phase voltage signal of each section of the busbar at the voltage detection hole to the monitoring system through bus communication. The structure is as follows: Figure 2 As shown, the first busbars of phase A, phase B and phase C close to the power supply line are numbered A1, B1 and C1, and the busbars of phase A, phase B and phase C of the second busbar are numbered A2, B2 and C2. The ground monitoring system can record the real-time phase voltage value U measured by the voltage monitoring device of each busbar section. a1 =220.5V, U b1 =220.2V, U c1 =219.7V…U an =207.5V, U bn =207.8V, U cn =207.2V. When the coke oven vehicle is working, the mobile vehicle will measure the real-time phase current value Ian , U bn , U cn and the current position value are transmitted to the monitoring system through the wireless communication system.

[0017] Step 2: Real-time online monitoring of busbar voltage drop. When the busbar is working normally, due to the conductor resistance of the busbar itself, there will be a voltage drop at the beginning and end of the busbar, and it will increase linearly with the increase of current. Taking phase A as an example, assuming that the conductor resistance of each section of the busbar of phase A from the power supply line is R a1 =0.007Ω、R a2 =0.006Ω、R a3 =0.007Ω…R an =0.0065Ω, the vehicle current monitoring device measures the current entering the vehicle through this phase as I an , then from the busbar inlet position to the vehicle slider power supply position, assuming that the A-phase busbar inlet voltage U a =222V, the busbar has 10 sections, and the phase current I under normal load conditions an If the current is 200A, the voltage drop ΔU generated by the first section of busbar is a1 Satisfy ΔU a1 =U a -U a1 =222V-220.5V=I an *R a1 ≈200A*0.007Ω, similarly, the voltage drop value ΔU generated in the second section a2 =U a1 -U a2 =220.5V-219.3V=I an *R a2 =200A*0.006Ω, and so on, the voltage drop value ΔU generated in the Nth section an =U a（n-1） -U an =I an *R an =200A*0.0065Ω=1.3V. Since the conductor resistance of each section of the busbar is similar, the voltage drop of each section of the busbar is approximately equal under normal power supply load, that is, ΔU a1 ≈ΔU a2 ≈…≈ΔU an ≈1.5V, the total voltage drop ΔU caused by the current flowing through the A-phase busbar can be obtained a =U a -U an =∑ΔU an =222V-207.5V=14.5V≈ΔU a1 +ΔUa2 +…+ΔU an When the voltage drop value of each section of the busbar calculated by the ground monitoring system satisfies the above formula, it means that the power supply status of each phase of the busbar is normal.

[0018] Step 3: Determine the power supply status of the busbar and locate the fault location. According to the ohmic characteristics, the greater the current, the more obvious the voltage drop across the resistor. Therefore, when the coke oven vehicle is performing a high-load process, the overall voltage drop value of the busbar will increase proportionally with the increase in current. The monitoring equipment can quickly detect abnormal power supply conditions of the busbar by measuring the voltage drop values ​​of each section of the busbar under high-load conditions such as when the pushing motor of the coke pushing car starts working, when the spiral coal feeding car is in the high-speed stage, when the dust removal fan of the coke intercepting car is turned on, and when the electric locomotive is in the highest speed stage. When the coke pushing car is working in the 5# busbar section area, the pushing motor starts working during the coke pushing process, and the working current of the coke pushing car reaches its peak at this moment. During the coke pushing process, the violent shaking of the car body will drive the busbars around the 5# busbar to shake. If the connection between the 4# and 5# busbars is loose, an instantaneous contact resistance ΔR=0.02Ω will be generated, making the resistance value of this section reach R a5 +ΔR=0.006Ω+0.02Ω=0.026Ω. According to Ohm's law, the abnormally increased pushing current will cause the voltage drop at this location to increase significantly. The pushing car transmits the working position and current value at this moment to the monitoring system. The monitoring system compares the voltage drop values ​​of each segment of the 1# to 10# busbar segments on the pushing car busbar. At this time, the voltage drop value of the 5# busbar of phase A is ΔU a5 =I a5 *(R a5 +ΔR)=200A*0.026Ω=5.2V or satisfy ΔU a5 >(1+α)∑ΔU an / n, where α is the allowable voltage drop bias rate. In this test embodiment, α=100%, that is, ΔU a5 >(1+α)∑ΔU an / n =(1+100%)*14.5V / 10=2.9V, which means that there is an abnormal voltage drop in the 5# section of busbar. The reason can be determined to be the abnormal contact resistance between the 4# and 5# busbar connecting pieces, thus enabling rapid judgment and location of the busbar fault.

[0019] Step 4: Calculate and monitor the resistance of the busbar. a1 , U a2 …U a（n-1） , U an and I an All of them are measured values ​​sent to the ground monitoring system. Therefore, according to Ohm's law, the relatively constant conductor resistance value R of each section of the busbar on each phase power supply circuit can also be obtained. a1 ≈Ra2 ≈…≈R an ≈(U a（n-1） -U an ) / I an =1.5V / 200A=0.0075Ω. This value is only related to the resistivity and length of the busbar itself. As the busbar resistance increases due to corrosion or poor contact, the ground monitoring system will compare the abnormal changes in the measured values ​​in real time to determine the abnormal condition and location of the busbar. When the vehicle is working at the 5# busbar position, the address value (5#) and the working current value are transmitted to the ground monitoring system, which records the maximum voltage drop ΔU of each section of the busbar from 1# to 5# on a certain phase power supply line. 1max =1.9V, ΔU 2max =2.1V…ΔU 4max =2V and ΔU 5max =6V, which is equal to the maximum working current I flowing through this phase at that moment max =300A ​​to calculate the resistance, and the resistance values ​​of each section of this phase busbar are R1=ΔU 1max / I max =1.9V / 300A=0.0063Ω、R2=ΔU 2max / I max =2.1V / 300A=0.007Ω…R5=ΔU 5max / I max =6V / 300A=0.02Ω, that is, the resistance value of 5# busbar reaches R5+ΔR=0.02Ω. If R5+ΔR>(1+β)R n , where β is the allowable resistance bias rate. In this test embodiment, β=100%, that is, R5+ΔR>(1+β)R n =(1+100%)*0.0075=0.015Ω, it can be determined that the resistance of the 5# busbar section is abnormal.

[0020] Example 2: This example is similar to Example 1 in most respects, except that Figure 3 As shown, in order to make the monitoring more accurate, a larger load current is required to make the abnormal voltage drop value stand out. Since the load of a coke oven vehicle is limited, if the busbar load allows, a vehicle on the same side of the power supply line can be set at the end to increase the load current of the busbar to make the abnormal value stand out, thereby realizing the rapid confirmation of the fault location. The busbar number of the power supply incoming line section of the entire busbar is 1#, and the end number is 10#. The 1# working vehicle is in the M# section (1≤M≤10), then a 2# mobile vehicle is set at the end 10# position to generate the rated load current I e =100A, I eThrough and 1# car working current I l The total current I that passes through the busbars 1# to M# is generated by superposition. e +I l =100A+200A=300A. The large load current causes the voltage drop through each section of the busbar to increase significantly, which is monitored by the ground voltage detection device. If there is a random resistance ΔR=0.01Ω caused by poor contact between the 1# busbar and the M# busbar, the total current will cause the intermittent contact resistance ΔR on the 1# to M# busbars to be displayed in the form of obvious abnormal voltage drop. The monitoring system samples the voltage drop of each section of the busbar at this moment and calculates the voltage drop of the busbar at the abnormal part to be ΔU mmax =(Ie+Il)*(R m +ΔR)=300A*(0.01*0.006)=4.8V, this voltage drop value will be greater than the voltage drop of other sections of the busbar or the average voltage drop of 2V, so that the abnormal busbar section can be quickly located through logical judgment.

[0021] The abnormal condition of the power supply system of the coke oven vehicle is found. If the voltage drop of each section of the busbar measured by the monitoring system is not abnormal, that is, the voltage drop of each section of the busbar is relatively uniform and is within the allowable value (1+α)∑ΔU m / M=1.5V, and the 1# coke oven vehicle still has obvious undervoltage during operation, while the 2# vehicle works normally at the same position, it can be judged that the power supply fault is in the 1# vehicle itself. When the 1# working vehicle is in the M# section of the busbar as the working vehicle, the rated load current I l =200A. Since the voltage drop of each section of the busbar from 1# to M# is uniform and the process functions of each vehicle are similar, the equipment driven by the vehicles in the same action process should be the same and the load should be similar. The 2# mobile vehicle will also work at the M# position as a reference vehicle, and the rated load current I e =180A. The current monitoring device on each car records the peak working current of the car in different working stages. Taking the coke pushing car as an example, the peak currents recorded by car 1# in the stages of door taking, dust removal opening, coke pushing, and coal leveling are I l1 =190A, I l2 =270A, I l3 =300A, I l4 =280A, etc., and the peak currents of the subsequent 2# car during the door taking, dust removal opening, coke pushing, and coal leveling stages are I e1 =170A, I e2 =200A, I e3 =280A, I e4 =260A, etc., compare the load current of the two vehicles at the same working process time. Under normal circumstances, I l=(1+г)I e , where г is the current allowable deviation. In this embodiment, г=10%. If there is always I l >(1+г)I e For example, the rated current of car 1# is increased to I l =240A, while the current of car 2# is still I at the same time in this position e =180A, it means that the 1# vehicle has an additional power load, which causes the current to be greater than that of the 2# vehicle for a long time. If I l >(1+г)I e , for example, the time when the dust removal fan is put into use, I l2 =270A, (1+г)I e2 = (1 + 10%) * 200 = 220A, which meets the abnormal judgment conditions of 1# pushing coke car. This means that the current of 1# car increases abnormally after the dust removal is turned on, and the dust removal system has abnormal power load conditions, resulting in a decrease in power supply voltage.

[0022] The present invention is not limited to the above embodiments. Any technical solution formed by equivalent replacement falls within the protection scope required by the present invention.

Claims

1. A method for locating a fault point of a busbar of a coke oven rail vehicle, characterized in that: The steps include: (1) A voltage monitoring device is installed beside all busbars of the track; the voltage monitoring device outputs the signal to the monitoring system; the monitoring system reads the voltage value measured by the voltage monitoring device; The current value and position information measured by the current monitoring device in the rail vehicle are output to the monitoring system; (2) Putting rail vehicles into production according to the production plan; (3) When the rail vehicle arrives at the predetermined operating position and starts to operate, the test section is from the power connection position of the track to the current position of the rail vehicle. The voltage drop on each busbar in the test section is calculated in turn, and the resistance of each busbar is calculated based on the current value; (4) If the resistance of a busbar exceeds the threshold, the busbar is judged to be faulty.

2. The method for locating the fault point of the busbar of a coke oven rail vehicle according to claim 1, characterized in that: A second rail vehicle is arranged at an operating position at the farthest end of the rail away from the power connection position of the rail and operated to generate a test current.

3. The method for locating the fault point of the busbar of a coke oven rail vehicle according to claim 1, characterized in that: The threshold in step (4) is (1+β)R n ; where R n is the standard resistance of the nth busbar, and β is the standard resistance bias rate.

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