CN203602719U - Selectable voltage type current drainage circuit structure - Google Patents

Selectable voltage type current drainage circuit structure Download PDF

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Publication number
CN203602719U
CN203602719U CN 201320693198 CN201320693198U CN203602719U CN 203602719 U CN203602719 U CN 203602719U CN 201320693198 CN201320693198 CN 201320693198 CN 201320693198 U CN201320693198 U CN 201320693198U CN 203602719 U CN203602719 U CN 203602719U
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China
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circuit
loop
drainage
pipe
current drainage
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CN 201320693198
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Chinese (zh)
Inventor
孙震洋
王双平
陈敬和
申满愉
陈杰
张喜海
邢晓乾
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铁道第三勘察设计院集团有限公司
天津赛德电气设备有限公司
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Priority to CN 201320693198 priority Critical patent/CN203602719U/en
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Abstract

The utility model provides a selectable voltage type current drainage circuit structure, the circuit structure comprises a current drainage loop, a control loop, a detection loop and a setting switch; the detection loop is connected with a pipe test terminal and a reference electrode of a metal pipe protecting circuit structure and orderly connected with the control loop and the current drainage loop, the control loop is connected with a setting switch; the current drainage loop is divided into a main loop and a standby loop and connected with a magnesium anode of the metal pipe protecting circuit structure. The intelligent current drainage as required function is realized through the circuit provided by the utility model, the whole current drainage system is free from the current drainage dead zone voltage so that the consumption of the magnesium is greatly reduced, and the operation cost is saved. The control loop can detect the working state of the main loop at fixed time per 2-4 hours, if the main loop is abnormally damaged, the structure can immediately switch to the standby loop, the negative potential of the magnesium anode is isolated by the standby loop and cannot be completely exerted on the pipe so as to prevent the metal pipe from hydrogen evolution reaction and pipeline insulation layer from falling off, and the current drainage of the pipe is safer and more reliable.

Description

可选电压式排流电路结构 Alternatively drain voltage circuit configuration of formula

技术领域 FIELD

[0001 ] 本实用新型涉及一种保护电气化铁路沿线油、气金属管道免于遭受杂散电流腐蚀的可选电压式排流电路结构。 [0001] The present invention relates to a protective electrified railway oil, gas metal pipes suffer from drainage selectable voltage circuit configuration of formula stray current corrosion.

背景技术 Background technique

[0002] 电气化铁路沿线的油、气金属管道防护,目前多采用强制排流方式,即无论管地电位如何,是否需要排流,排流装置都通过二极管直接连接管道与镁阳极,进行强制排流。 [0002] Oil along the electrified railway, gas metal pipe protection, the current use of forced discharge flow mode, i.e., regardless of possession of potential, the need for drainage, drainage means are directly connected to pipeline and magnesium anode through the diode, the forced discharge flow. 该方式结构简单,但智能性较差,监测维护难度大,带来的弊端主要表现在: This way a simple structure, but poor intelligence, surveillance difficult maintenance, the evils of the main problems:

[0003] 1、由于不设定管道保护电压,也不能区分管道上是否产生感应干扰,采用直接排流,因此埋地镁阳极在实际不需要排流的状态下也造成消耗,从而减少阳极使用寿命,增加运营成本; [0003] 1, since no pipeline protection voltage setting, can not distinguish whether the interference induced on the pipe by direct drainage, so buried in a state where the magnesium anode does not require actual drain is also caused by consumption, reduce the use of the anode life and increase operating costs;

[0004] 2、由于二极管工作电压等参数影响,当镁阳极过氧化后负电位不足时,或当管地电位低于二级管正常工作电压时,二极管无法顺利正向导通,存在排流盲区; [0004] 2, due to diode parameters such as operating voltage, when the magnesium anode peroxide insufficient negative potential or a ground potential when the tube below the normal operating voltage of the diode, the diode is forward trouble, the presence of blind drainage ;

[0005] 3、当二极管反向击穿损坏后,镁阳极的负电位会完全施加在管道上,此时就会对管道造成过保护,会使管道发生析氢反应,造成管道绝缘层脱落,反而加速了管道的氧化腐蚀。 [0005] 3, when the diode reverse breakdown damage, a negative potential is applied to the magnesium anode is completely on the pipe, then the pipe will result in over-protection, make pipeline hydrogen evolution reaction occurs, resulting in an insulating layer off the pipe, but accelerated oxidation corrosion of the pipeline.

[0006] 随着油管道产权单位对杂散电流认识的逐步加深,对排流提出“选择排流”等新要求,即要求排流在满足设定的某些条件下方可排流,减少排流装置对既有管道防腐蚀设备的影响。 [0006] With the oil conduit unit of the gradually deepening property stray current knowledge, new requirements "select drain" and the like for drainage, i.e. the drainage requires only outflow under certain conditions set to reduce the discharge Effect of the flow conduit device has both anti-corrosion device. 而现今采用的排流结构均基于强制排流的原理,不能满足新的要求。 The drainage structure used today are based on the principle of forced drainage can not meet the new requirements. 对此,急需对新型排流结构进行研究。 In this regard, the urgent need to study the new drainage structure.

发明内容 SUMMARY

[0007]为了解决电气化铁路附近的油、气金属管道上的杂散电流一直采用的强制排流方式,本实用新型目的是提供一种可选最佳阴极保护电压的管道排流方法,减少排流装置对既有管道防腐蚀设备的影响,并降低运营维护成本。 [0007] In order to solve the forced draining oil near the embodiment electrified railway, stray current on the gas pipe has been used a metal, the present invention aims to provide an alternative preferred cathodic protection voltage of the drain pipe methods, reduce the emission of Effect of the flow conduit device has both anti-corrosion equipment, reduce operating and maintenance costs.

[0008] 为实现上述目的,本实用新型采取的技术方案是提供一种可选电压式排流结构,该排流结构与金属管道防护电路结构相连接,其中:该电路结构包括有排流回路、控制回路、检测回路及设定开关; [0008] To achieve the above object, the present invention adopted an alternative technical solution is to provide a voltage-type drainage structure, the protective structure and drainage pipe connected to the metal circuit configuration, wherein: the circuit arrangement comprises a flow circuit with a discharge , control circuit, and setting switch detecting circuit;

[0009] 所述检测回路连接金属管道防护电路结构的管道测试端子和参比电极,并依次与控制回路、排流回路相连接,控制回路连接设定开关;所述排流回路分为主回路和备用回路,并与金属管道防护电路结构的镁阳极连接; [0009] The detecting circuit connecting line test terminal and a reference electrode of the protection circuit configuration of metal pipes, and in turn to the control circuit, the discharge flow circuit connected to the connection setting switch control circuit; said main circuit discharge flow loop and a standby circuit, and connected to the circuit configuration of the protective magnesium anode metal pipe;

[0010] 所述检测回路对金属管道电位实时监测并与参比电极对比得到管地电位信号,送至控制电路,控制回路通过与设定开关设定的控制电压信号进行逻辑判断后,当需要进行排流时则向排流回路发出导通信号,导通排流主回路,使流过金属管道上的杂散电流经镁阳极流回大地;当不需要排流时,控制回路向排流回路发出关断信号,排流主回路断开,停止排流;[0011]当排流主回路故障时,排流回路向控制回路发送故障信号,控制回路向排流主回路发送断开信号,断开主回路,同时自动投入排流备用回路。 After [0010] Real-time monitoring of the detection circuit and the potential of the metal conduit tube ground electrode to obtain a reference signal comparison, to the control circuit, the control logic circuit is determined by the control voltage signal with a setting switch, and when needed when drainage is issued to the discharge flow circuit oN signal, the main circuit is turned on drainage, so that the stray current flows through the anode of magnesium metal pipes back into the earth; when no drainage, the drainage control loop a turn off signal circuit, the main circuit is disconnected drainage, drainage stopped; [0011] when the exhaust stream of the main circuit fault, the discharge flow circuit transmits a fault signal to the control circuit, the control circuit to the discharge stream of the main transmission circuit oFF signal, disconnect the main circuit, and automatically draining into the standby circuit.

[0012] 本实用新型的有益效果如下: [0012] The advantageous effects of the present invention are as follows:

[0013] 1、通过引进检测电路、CRJ控制电路、设定开关,主回路,所以整个系统不是简单的将管道和镁阳极直连,而是通过管地电位的判定结果来确定是否打开主回路连接管道与镁阳极,实现了智能化的“按需排流”功能; [0013] 1, through the introduction of a detection circuit, a control circuit CRJ, setting switch, the main circuit, so the whole system is not simply a pipe directly connected to the anode and magnesium, but to determine whether the host pipe loop by the determination result of the ground potential connecting duct with magnesium anode realize intelligent "on-demand draining" function;

[0014] 2、主回路连接管道与镁阳极的元器件不是二极管,而是采用无压降的场效应开关管,所以整个排流系统不存在排流盲区电压; [0014] 2, the main circuit is connected to the duct components not magnesium anode diode, instead of using no drop FET switch, the entire drainage system outflow blind voltage is present;

[0015] 3、使用了“按需排流”的控制结构,所以整个系统不是一直在排流,而是根据管地电位与设定保护电位的比较间歇性排流,故镁阳极的消耗大为降低,节省运营费用; [0015] 3, a control structure of "on-demand drain", the entire system is not always in the exhaust stream, but to protect a potential flow and intermittent discharge tube according to the set ground potential, so that a large consumption of magnesium anode to reduce, save operating costs;

[0016] 4、每2至4个小时,控制电路都会定时检测主回路工作状态,如果主回路损坏异常,则马上切换到备用回路,因此镁阳极的负电位被备用回路隔离而无法完全施加在管道上,从而避免了管道发生析氢反应,管道绝缘层脱落等现象,使管道排流运行更加安全可 [0016] 4, every two to four hours, the control circuit will be the timing of detection of the main circuit operation state, if the main circuit is damaged abnormality is immediately switched to the standby loop, and therefore magnesium anode negative potential is the standby loop isolation can not be fully applied to the pipe, thus avoiding the occurrence of the phenomenon of the hydrogen evolution reaction pipe, the pipe off the insulating layer, so that the pipe may be safer drainage operation

与芦O Lo and O

附图说明 BRIEF DESCRIPTION

[0017] 图1为本实用新型的可选电压式排流电路结构原理图。 [0017] FIG. 1 is novel selectable voltage type circuit configuration diagram outflow present invention.

[0018] 图2为本实用新型的可选电压式排流结构主要电路示意图。 [0018] FIG novel alternative-voltage circuit schematic of the main drainage structure present invention.

具体实施方式 Detailed ways

[0019] 结合附图对本实用新型的可选电压式排流电路结构加以说明。 [0019] conjunction with the accompanying drawings of the present invention will be described an alternative circuit configuration of the voltage-type drainage.

[0020] 本实用新型的可选电压式排流电路结构的设计思想是基于,阴极保护电位根据使用条件而设定,在满足设定条件情况下方可排流,根据环境条件而设定阴极保护电压,实现按需排流的智能电路结构。 [0020] The design of the present invention of formula drainage selectable voltage circuit configuration is based on cathodic protection potential is set according to use conditions, the exhaust stream before the condition is met in the case, cathodic protection is set for the environmental conditions voltage, the circuit configuration of the discharge-demand intelligent streams. 将排流回路一端连接到金属管道,另一端连接到镁阳极,通过检测回路比较管道实测的电压与设定开关的预设电压进行比较,根据逻辑判定结果,控制回路决定排流回路是导通还是截止。 Exhaust flow circuit connected to a metal pipe end and the other end connected to an anode of magnesium, by comparing the preset voltage detection circuit comparing the measured voltage with the pipe switch is set, according to the logical determination result, the control circuit determines the discharge flow circuit is turned on or off. 同时排流回路设有常规二极管排流的备用通路,在主回路出现故障时,可以通过控制投入备用回路。 At the same time the discharge flow circuit is provided with alternate paths of a conventional drain diode, when the main circuit fails, the control circuit can be put into standby.

[0021 ] 本实用新型的可选电压式排流电路结构,该排流结构与金属管道防护电路结构相连接,该电路结构包括有排流回路、控制回路、检测回路及设定开关; [0021] Alternatively the present invention of formula drain voltage circuit configuration, the drainage structure of the metal protection pipe is connected to a circuit configuration, the circuit arrangement comprises a drainage circuit, control circuit, and setting switch detecting circuit;

[0022] 所述检测回路连接金属管道防护电路结构的管道测试端子和参比电极,并依次与控制回路、排流回路相连接,控制回路连接设定开关;所述排流回路分为主回路和备用回路,并与金属管道防护电路结构的镁阳极连接。 [0022] The detecting circuit connecting line test terminal and a reference electrode of the protection circuit configuration of metal pipes, and in turn to the control circuit, the discharge flow circuit connected to the connection setting switch control circuit; said main circuit discharge flow loop and a standby circuit, and is connected to an anode of magnesium metal pipe protection circuit configuration.

[0023] 如图1所示,当大地中的杂散电流流经埋地金属管道时,检测回路实时监测管道电位并与参比电极对比得到管地电位信号,送至控制电路,控制回路通过与设定开关设定的控制电压信号进行逻辑判断后,当需要进行排流时则向排流回路发出导通信号,导通排流回路,使流经管道上的杂散电流经镁阳极流回大地;当不需要排流时,控制回路向排流回路发出关断信号,排流回路断开,停止排流。 [0023] As shown in FIG. 1, when the stray current flows through a metal pipe buried in the earth, a potential detection circuit and real-time monitoring of the tube conduit ground electrode to obtain a reference signal comparison, to the control circuit, the control loop through after the setting switch control logic determines the voltage signal, when the drain is required on signal is issued to the discharge flow circuit, conducting exhaust flow circuit, the stray current on the magnesium-anode flow through the conduit back to the earth; when no drainage, the control circuit oFF signal sent to the discharge flow circuit, the discharge flow circuit to stop their drainage.

[0024]当排流主回路故障时,排流回路向控制回路发送故障信号,控制回路向排流主回路发送断开信号,断开主回路,同时自动投入排流备用回路。 [0024] When the exhaust stream of the main circuit fault, the discharge flow circuit transmits a fault signal to the control circuit, the control circuit transmits a release signal to the exhaust stream of the main circuit, the main circuit is disconnected, while automatic backup into the drain circuit. [0025] 本实用新型的可选电压式排流结构电路启动时,系统先做排流主回路和备用回路自检测,如果检测到主回路损坏,则系统自动投入备用回路,进入非智能化的强制排流状态。 When [0025] the present invention of formula drainage structure optional voltage circuit starts to do first drainage system and the standby circuit from the main circuit is detected, the main circuit is detected if damaged, the system automatically into the standby circuit, into a non-intelligent forced drainage state. 在可选电压排流状态下,检测电路实时监测管道对参比电极的电位即管地电位,将检测到的电位信号送控制电路;设定开关则是根据现场土壤电导率湿度等情况,设定管道的保护电位。 In the alternative the drain voltage state, real-time monitoring circuit detects the potential of the signal sent to the control conduit circuit reference electrode potential, i.e. the tube, the detected; switch is set according to the situation on-site soil moisture conductivity and the like, provided scheduled pipeline protection potential. 当检测电路实时监测的管地电位大于设定的保护电位时,说明此时管道电位正在正向极化,需要主回路连接镁阳极排流,于是控制电路导通排流主回路,使管道与镁阳极连通,进入排流状态;当检测电路实时监测的管地电位小于设定的保护电位时,说明此时管道电位正在反向极化,于是控制电路此时便关闭排流主回路,进入禁止排流状态。 When the real-time monitoring of the ground potential detection circuit pipe is greater than the set protection potential, the potential of the pipeline at this time is described positive polarization, the main circuit connection needs magnesium anode exhaust stream, and the control circuit turns on the discharge stream of the main circuit, and the pipe magnesium anode communication state into the exhaust stream; real-time monitoring when the detection circuit ground potential is less than the tube set protection potential, the potential of the pipeline at this time is described reverse polarization, and the control circuit at this time will drain off the main circuit, into the prohibit the discharge flow state. 同时,每2至4个小时,控制电路都会定时检测主回路工作状态,如果主回路损坏,则切换到备用回路排流。 Meanwhile, every 2-4 hours, a timing control circuit will detect the primary circuit operating state, if the main circuit is damaged, the circuit is switched to the standby drainage.

[0026] 如图2所示,本实用新型的可选电压式排流电路结构的主要电气元件由运算放大器、设定开关、高速单片机、继电器Jl,场效应大功率开关管ZL1、二极管ZL2组成。 [0026] 2, the present invention optionally-voltage main electrical components drainage circuit configuration of an operational amplifier, the switch setting, high-speed microcontroller, the relay of Jl, ZL1 of FET power switch, a diode consisting ZL2 . 电路通电启动后,高速单片机控制继电器Jl导通带电,继电器常开接点Jl-1闭合,常闭接点J1-2打开,投入场效应大功率开关管ZLl构成的排流主回路,并隔离二极管ZL2构成排流备用回路。 After power-up circuit, Jl speed microprocessor control relay is turned charged, normally open relay contacts Jl-1, normally closed contacts J1-2 open, the flow into the discharge FET power switch main circuit configuration ZLl, and isolation diodes ZL2 constituting the drain backup circuit. 运算放大器一端接参比电极,另一端接管道测试端子,检测管地电位变化,得到实时变化的电压信号Xl送至高速单片机,设定开关将控制电压信号X2也送入高速单片机,高速单片机对Xl与X2信号进行逻辑判定,如果X1>X2,则输出启动信号开通场效应大功率开关管ZL1,主回路导通开始排流;如果X1〈X2,则输出关闭信号关闭场效应大功率开关管ZLl停止排流。 End of the operational amplifier a reference electrode, the other end of the pipe test terminals, the ground potential detector tube change, in real time varying voltage signal to the high-speed microcontroller Xl, setting switch the control voltage signal is also fed to high-speed microcontroller X2, speed microprocessor for Xl and X2 signal logic decision, if X1> X2, then the output enable signal ZL1 of turn FET power switch, the main circuit starts conducting exhaust stream; if X1 <X2, the closing signal output FET power switch off ZLl stop drainage. 如果主回路发生故障,高速单片机控制继电器Jl断电,常开接点Jl-1打开,常闭接点J1-2闭合,使排流工作在备用回路上。 If the main circuit fails, Jl speed microprocessor control relays de-energized, normally open contacts Jl-1 open, normally closed contact J1-2 is closed, the exhaust flow of working in slave loop.

[0027] 本实用新型的可选电压式排流电路结构,改变了电气化铁路附近的油、气管道上杂散电流一直采用的强制排列方式,即不论金属管道上杂散电流情况如何,均将管道与镁阳极直接连接,解决了油气管道在不同的外界环境中根据需要设定最佳保护电位的问题。 [0027] Alternatively the present invention of formula drain voltage circuit configuration, the change of oil near the electrified railway track pipe arrangement forced stray current has been used, i.e., regardless of how the stray current on the metal pipe, the pipe will have magnesium anode connected directly to solve the problem of the potential oil and gas pipeline set optimal protection in different ambient environment as needed.

Claims (1)

1.一种可选电压式排流电路结构,该排流电路结构与金属管道防护电路结构相连接,其特征是:该电路结构包括有排流回路、控制回路、检测回路及设定开关; 所述检测回路连接金属管道防护电路结构的管道测试端子和参比电极,并依次与控制回路、排流回路相连接,控制回路连接设定开关;所述排流回路分为主回路和备用回路,并与金属管道防护电路结构的镁阳极连接; 所述检测回路对金属管道电位实时监测并与参比电极对比得到管地电位信号,送至控制电路,控制回路通过与设定开关设定的控制电压信号进行逻辑判断后,当需要进行排流时则向排流回路发出导通信号,导通排流主回路,使流过金属管道上的杂散电流经镁阳极流回大地;当不需要排流时,控制回路向排流回路发出关断信号,排流主回路断开,停止排流; 当排流主回路故障时,排 An alternative-voltage discharge current circuit configuration, circuit configuration and circuit configuration of the metal protection pipe is connected to the drain, characterized in that: the circuit arrangement comprises a drainage circuit, control circuit, and setting switch detecting circuit; the detection circuit connected to the test terminals and pipe protection circuit configuration of a reference electrode metal pipes, and in turn to the control circuit, the discharge flow circuit connected to the connection setting switch control circuit; said drain circuit and the standby circuit main circuit and magnesium metal shield circuit connected to the anode of the pipeline structure; real-time monitoring of the detection circuit potential of the metal pipe and the pipe a ground potential signal obtained comparative reference electrode, to the control circuit, the control circuit by setting the set switch after determination logic control voltage signal, when the required exhaust stream sent to the discharge flow circuit oN signal, the main circuit is turned on drainage, so that the stray current flows through the anode of magnesium metal pipes back into the earth; if not when required drainage, the control circuit oFF signal sent to the discharge flow circuit, the main circuit is disconnected drainage, drainage stopped; when the exhaust stream of the main circuit failure, row 回路向控制回路发送故障信号,控制回路向排流主回路发送断开信号,断开主回路,同时自动投入排流备用回路。 Loop failure signal to the transmission control circuit, the control circuit transmits a release signal to the exhaust stream of the main circuit, the main circuit is disconnected, while automatic backup into the drain circuit.
CN 201320693198 2013-11-05 2013-11-05 Selectable voltage type current drainage circuit structure CN203602719U (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105154888A (en) * 2015-08-06 2015-12-16 北京市燃气集团有限责任公司 Alternating current relieving method suitable for town gas pipe network
CN107863767A (en) * 2016-09-22 2018-03-30 中国石油天然气股份有限公司 Oil-gas pipeline valve chamber earth protective device
CN108169547A (en) * 2017-11-14 2018-06-15 中国船舶重工集团公司第七二五研究所 Drainage method and device is detected automatically for the stray electrical current of ship seawaterline

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105154888A (en) * 2015-08-06 2015-12-16 北京市燃气集团有限责任公司 Alternating current relieving method suitable for town gas pipe network
CN107863767A (en) * 2016-09-22 2018-03-30 中国石油天然气股份有限公司 Oil-gas pipeline valve chamber earth protective device
CN107863767B (en) * 2016-09-22 2019-05-07 中国石油天然气股份有限公司 Oil-gas pipeline valve chamber earth protective device
CN108169547A (en) * 2017-11-14 2018-06-15 中国船舶重工集团公司第七二五研究所 Drainage method and device is detected automatically for the stray electrical current of ship seawaterline

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