CN105203918A - Extra-high voltage alternating current transmission line three-phase short-circuit fault distance detection method based on single-ended electrical quantity - Google Patents

Abstract

Translated fromChinese

本发明公开了一种基于单端电气量特高压交流输电线路三相短路故障测距方法。采用一维搜索方法依次计算特高压交流输电线路正常运行时保护安装处的相间电压领先特高压交流输电线路三相短路故障后特高压交流输电线路上每一点相间电压的相角，然后利用特高压交流输电线路三相短路故障点前后，特高压交流输电线路的相角由(-90°90°)突变进入(90°270°)，且另一相电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的另一相电压的相角也由(-90°90°)突变进入(90°270°)这一相位特性实现单端精确定位，测距精度不受过渡电流、负荷电流和电力系统运行方式等因素的影响，具有很高的测距精度。

The invention discloses a distance measurement method for a three-phase short-circuit fault of a UHV AC transmission line based on a single-end electrical quantity. The one-dimensional search method is used to calculate the phase-to-phase voltage at the protection installation place leading the UHV AC transmission line during normal operation. Before and after the three-phase short-circuit fault point of the AC transmission line, the phase angle of the UHV AC transmission line changes suddenly from (-90°90°) to (90°270°), and the voltage of the other phase leads the three-phase short-circuit fault of the UHV AC transmission line The phase angle of the other phase voltage before and after the three-phase short-circuit fault point of the UHV AC transmission line also changes suddenly from (-90°90°) to (90°270°) This phase characteristic realizes single-ended precise positioning and ranging accuracy It is not affected by factors such as transition current, load current and power system operation mode, and has high ranging accuracy.

Description

Translated fromChinese

基于单端电气量特高压交流输电线路三相短路故障测距方法Three-phase short-circuit fault location method for UHV AC transmission lines based on single-ended electrical quantities

技术领域technical field

本发明涉及电力系统继电保护技术领域，具体地说是涉及一种基于单端电气量特高压交流输电线路三相短路故障测距方法。The invention relates to the technical field of electric power system relay protection, in particular to a three-phase short-circuit fault distance measurement method for UHV AC transmission lines based on single-ended electrical quantities.

背景技术Background technique

从测距所用电气量来划分，故障测距的方法可分为两大类：双端测距和单端测距。双端故障测距法是利用输电线路两端电气量确定输电线路故障位置的方法，它需要通过通道获取对端电气量，因此对通道的依赖性强，实际使用中还易受双端采样值同步性的影响。单端测距法是仅利用输电线路一端的电压电流数据确定输电线路故障位置的一种方法，由于它仅需要一端数据，无须通讯和数据同步设备，运行费用低且算法稳定，因此在中低压线路中获得了广泛地应用。目前，单端测距方法主要分为两类，一类为行波法，另一类为阻抗法。行波法利用故障暂态行波的传送性质进行测距，精度高，不受运行方式、过度电阻等影响，但对采样率要求很高，需要专门的录波装置，目前未获得实质性的应用。阻抗法利用故障后的电压、电流量计算故障回路的阻抗，根据线路长度与阻抗成正比的特性进行测距，简单可靠,但受到故障的过渡电阻、线路不完全对称等因素的影响。由于高压输电线路沿线存在较大的分布电容电流，当高压输电线路发生中高阻短路故障时，单端阻抗法测距结果会严重偏离真实故障距离，不能满足现场的应用要求。因此，采用集中参数建模的单端阻抗法不能直接应用于高压输电线路的故障测距。Divided from the electrical quantity used for distance measurement, fault location methods can be divided into two categories: double-ended ranging and single-ended ranging. The double-terminal fault location method is a method to determine the fault location of the transmission line by using the electrical quantity at both ends of the transmission line. It needs to obtain the electrical quantity of the opposite end through the channel, so it is highly dependent on the channel, and it is also vulnerable to the double-terminal sampling value in actual use. Synchronization effects. The single-ended ranging method is a method that only uses the voltage and current data at one end of the transmission line to determine the fault location of the transmission line. Because it only needs data at one end, does not require communication and data synchronization equipment, and has low operating costs and stable algorithms, it is suitable for medium and low voltage applications. It has been widely used in the line. At present, the single-ended ranging methods are mainly divided into two categories, one is the traveling wave method, and the other is the impedance method. The traveling wave method utilizes the transmission properties of fault transient traveling waves for distance measurement. It has high precision and is not affected by the operation mode and excessive resistance. application. The impedance method calculates the impedance of the fault loop by using the voltage and current after the fault, and performs distance measurement according to the characteristic that the length of the line is proportional to the impedance. It is simple and reliable, but it is affected by factors such as the transition resistance of the fault and the incomplete symmetry of the line. Due to the large distributed capacitive current along the high-voltage transmission line, when a medium-to-high-resistance short-circuit fault occurs on the high-voltage transmission line, the ranging result of the single-ended impedance method will seriously deviate from the real fault distance, which cannot meet the application requirements of the site. Therefore, the single-ended impedance method using lumped parameter modeling cannot be directly applied to fault location of high-voltage transmission lines.

采用分布参数模型研究高压输电线路单端故障测距逐渐引起了广大学者的关注。哈恒旭、张保会、吕志来等人发表的《高压输电线路单端测距新原理探讨》采用分布参数建模，利用单端电压电流计算沿线电压对距离导数的范数在线路上的分布进行故障点的定位。该方法涉及了大量的求导运算和积分运算，所需运算量大，算法复杂不易实现。林湘宁、黄小波等人发表的《基于分布参数模型的比相式单相故障单端测距算法》采用分布参数建模，根据故障点处的残压与故障电流同相位特征进行故障定位。该方法改善了分布电容对单端阻抗法故障测距的影响，但在高阻接地故障时测距误差达到-2.38％，误差绝对值大于1.5％，不能满足现场的应用要求。王宾、董新洲等人发表的《特高压长线路单端阻抗法单相接地故障测距》采用分布参数建模，利用观测点处负序电流的相角估算故障点电压的相角，然后在故障点电压瞬时值过零点时刻计算测量阻抗。该方法在中低阻短路故障时，由于沿线电压下降明显，利用观测点处负序电流相角估算故障点电压相角存在的误差对测距结果影响不大；但在高阻短路故障时，由于线路沿线各点电压相差很小，利用观测点处负序电流相角估算故障点电压相角存在的误差加上暂态过程的影响，该方法测距误差较大。The use of distributed parameter models to study single-ended fault location of high voltage transmission lines has gradually attracted the attention of many scholars. Ha Hengxu, Zhang Baohui, Lu Zhilai and others published "Discussion on the New Principle of Single-End Ranging of High-Voltage Transmission Lines" using distributed parameter modeling, using single-end voltage and current to calculate the distribution of the norm of the voltage-to-distance derivative along the line on the fault point positioning. This method involves a large number of derivation operations and integral operations, which requires a large amount of operations, and the algorithm is complex and difficult to implement. Lin Xiangning, Huang Xiaobo and others published "Phase-Comparison Single-Phase Fault Single-End Distance Measurement Algorithm Based on Distributed Parameter Model" using distributed parameter modeling to locate faults according to the same phase characteristics of residual voltage and fault current at the fault point. This method improves the influence of distributed capacitance on fault location by single-ended impedance method, but the distance measurement error reaches -2.38% when the high-impedance ground fault occurs, and the absolute value of the error is greater than 1.5%, which cannot meet the application requirements of the field. Wang Bin, Dong Xinzhou, etc. published "UHV long line single-ended impedance method single-phase ground fault location" using distributed parameter modeling, using the phase angle of the negative sequence current at the observation point to estimate the phase angle of the fault point voltage, and then Calculate the measured impedance at the moment when the instantaneous value of the voltage at the fault point crosses zero. In the case of medium and low-resistance short-circuit faults, due to the obvious drop in voltage along the line, the error in estimating the voltage phase angle of the fault point by using the negative-sequence current phase angle at the observation point has little effect on the ranging results; but in the case of high-resistance short-circuit faults, Since the voltage difference of each point along the line is very small, the error in estimating the voltage phase angle of the fault point by using the negative-sequence current phase angle at the observation point and the influence of the transient process, the distance measurement error of this method is relatively large.

发明内容Contents of the invention

本发明的目的在于克服已有技术存在的不足，提供一种基于单端电气量特高压交流输电线路三相短路故障测距方法，该方法利用特高压交流输电线路三相短路故障点前后，特高压交流输电线路正常运行时保护安装处的相间电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的相间电压的相角由(-90°90°)突变进入(90°270°)，且特高压交流输电线路正常运行时保护安装处另一相电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的另一相电压的相角也由(-90°90°)突变进入(90°270°)这一相位特性实现特高压交流输电线路三相短路故障的单端精确定位，测距精度不受过渡电流、负荷电流和电力系统运行方式等因素的影响，具有很高的测距精度。The purpose of the present invention is to overcome the deficiencies in the prior art, and to provide a method for measuring the location of three-phase short-circuit faults of UHV AC transmission lines based on single-ended electrical quantities. When the high-voltage AC transmission line is in normal operation, the phase-to-phase voltage at the protection installation is leading. After the three-phase short-circuit fault of the UHV AC transmission line, the phase angle of the phase-to-phase voltage before and after the three-phase short-circuit fault point of the UHV AC transmission line changes suddenly from (-90°90°) Enter (90°270°), and when the UHV AC transmission line is in normal operation, protect the other phase voltage at the installation place ahead of the UHV AC transmission line three-phase short-circuit fault and the other phase before and after the UHV AC transmission line three-phase short-circuit fault point The phase angle of the voltage also changes suddenly from (-90°90°) to (90°270°). This phase characteristic realizes the single-end precise positioning of the three-phase short-circuit fault of the UHV AC transmission line, and the ranging accuracy is not affected by the transition current, load Influenced by factors such as current and power system operation mode, it has high ranging accuracy.

为完成上述目的，本发明采用如下技术方案：For accomplishing above-mentioned object, the present invention adopts following technical scheme:

基于单端电气量特高压交流输电线路三相短路故障测距方法，其特征在于，包括如下依序步骤：A three-phase short-circuit fault location method for UHV AC transmission lines based on single-ended electrical quantities is characterized in that it includes the following sequential steps:

(1)保护装置测量特高压交流输电线路正常运行时的三相电压和三相电流其中，φαβ＝ABC、BCA、CAB相；(1) The protection device measures the three-phase voltage of the UHV AC transmission line during normal operation and three-phase current Among them, φαβ=ABC, BCA, CAB phase;

(2)保护装置测量特高压交流输电线路三相短路故障后的三相电压和三相电流零序电流其中，φαβ＝ABC、BCA、CAB相；(2) The protection device measures the three-phase voltage after the three-phase short-circuit fault of the UHV AC transmission line and three-phase current Zero sequence current Among them, φαβ=ABC, BCA, CAB phase;

(3)保护装置选取故障距离初始值为l_x，计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的αβ相间电压其中，Z_c1为特高压交流输电线路正序波阻抗；γ₁为特高压交流输电线路正序传播系数；φαβ＝ABC、BCA、CAB相；th(.)为双曲正切函数；(3) The protection device selects the initial value of the fault distance as l_x , and calculates the αβ phase-to-phase voltage at a point l_x away from the protection installation of the UHV AC transmission line after the three-phase short-circuit fault of the UHV AC transmission line Among them, Z_c1 is the positive sequence wave impedance of the UHV AC transmission line; γ₁ is the positive sequence propagation coefficient of the UHV AC transmission line; φαβ=ABC, BCA, CAB phase; th(.) is the hyperbolic tangent function;

(4)计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的φ相电压其中，Z₀为特高压交流输电线路保护安装处的系统零序等值阻抗；γ₁、γ₀分别为特高压交流输电线路正序、零序传播系数；Z_c1、Z_c0分别为特高压交流输电线路正序、零序波阻抗；$k\left(l_x\right)=\frac{Z_{0}ch\left({\mathrm{\γ}}_0{l}_x\right)+Z_{c0}sh\left({\mathrm{\γ}}_0{l}_x\right)-Z_{0}ck\left({\mathrm{\γ}}_1{l}_x\right)}{Z_{c1}sh\left({\mathrm{\γ}}_1{l}_x\right)}-1,$为距离特高压交流输电线路保护安装处l_x点的零序补偿系数；th(.)为双曲正切函数；ch(.)为双曲余弦函数；sh(.)为双曲正弦函数；(4) Calculate the φ-phase voltage at the point l_x away from the UHV AC transmission line protection installation after the three-phase short-circuit fault of the UHV AC transmission line Among them, Z₀ is the zero-sequence equivalent impedance of the system where the UHV AC transmission line protection is installed; γ₁ and γ₀ are the positive-sequence and zero-sequence propagation coefficients of the UHV AC transmission line respectively; Z_c1 and Z_c0 are the UHV Positive-sequence and zero-sequence wave impedance of AC transmission lines;$k\left(l_x\right)=\frac{Z_{0}ch\left({\mathrm{\γ}}_0{l}_x\right)+Z_{c0}\mathrm{the\; s}h\left({\mathrm{\γ}}_0{l}_x\right)-Z_{0}ck\left({\mathrm{\γ}}_1{l}_x\right)}{Z_{c1}\mathrm{the\; s}h\left({\mathrm{\γ}}_1{l}_x\right)}-1,$ is the zero-sequence compensation coefficient of a point l_x away from the UHV AC transmission line protection installation; th(.) is a hyperbolic tangent function; ch(.) is a hyperbolic cosine function; sh(.) is a hyperbolic sine function;

(5)计算${\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{U}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{U}}_{\mathrm{\β}\[0\]}$领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right);$(5) calculation${\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{u}}_{\mathrm{\α}\[0\]}-{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\β}\[0\]}$ take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right);$

(6)计算领先的相角$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right);$(6) calculation take the lead phase angle of$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right);$

(7)故障距离l_x以固定步长Δl递增，返回步骤(3)，依次计算特高压交流输电线路上每一点处${\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{U}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{U}}_{\mathrm{\β}\[0\]}$领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$和领先的相角直至特高压交流输电线路全长；(7) The fault distance l_x increases with a fixed step size Δl, return to step (3), and calculate the distance at each point on the UHV AC transmission line${\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{u}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{u}}_{\mathrm{\β}\[0\]}$ take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$ and take the lead phase angle of Up to the full length of the UHV AC transmission line;

(8)保护装置选取特高压交流输电线路上某一l_x点的落在(-90°90°)和$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{\stackrel{\·}{U}\mathrm{\φ}\left(l_x\right)}\right)$落在(-90°90°)，且其相邻一下个l_x+Δl的$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$落在(90°270°)和落在(90°270°)，则这两个点的中间位置即为特高压交流输电线路三相短路故障点。(8) The protection device selects a certain_lx point on the UHV AC transmission line falls on (-90°90°) and$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{\stackrel{\·}{u}\mathrm{\φ}\left(l_x\right)}\right)$ Falls on (-90°90°), and it is adjacent to the next l_x +Δl$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$ falls on (90°270°) and (90°270°), the middle of these two points is the three-phase short-circuit fault point of the UHV AC transmission line.

本发明与现有技术相比较，具有下列积极成果：Compared with the prior art, the present invention has the following positive results:

本发明方法采用分布参数精确描述特高压交流输电线路电压电流传输的物理过程，具有天然的抗分布电容电流的能力。本发明方法利用特高压交流输电线路三相短路故障点前后，特高压交流输电线路正常运行时保护安装处的相间电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的相间电压的相角由(-90°90°)突变进入(90°270°)，且特高压交流输电线路正常运行时保护安装处另一相电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的另一相电压的相角也由(-90°90°)突变进入(90°270°)这一相位特性实现特高压交流输电线路三相短路故障的单端精确定位，测距精度不受过渡电流、负荷电流和电力系统运行方式等因素的影响，具有很高的测距精度。The method of the invention uses distribution parameters to accurately describe the physical process of voltage and current transmission of UHV AC transmission lines, and has natural ability to resist distributed capacitance current. The method of the present invention utilizes before and after the three-phase short-circuit fault point of the UHV AC transmission line, and when the UHV AC transmission line is in normal operation, the phase-to-phase voltage at the protection installation place is ahead of the three-phase short-circuit fault of the UHV AC transmission line after the UHV AC transmission line three-phase short-circuit fault The phase angle of the phase-to-phase voltage before and after the point changes from (-90°90°) to (90°270°), and when the UHV AC transmission line is in normal operation, the other phase voltage at the protection installation is ahead of the three-phase short circuit of the UHV AC transmission line After the fault, the phase angle of the other phase voltage before and after the three-phase short-circuit fault point of the UHV AC transmission line also changes suddenly from (-90°90°) to (90°270°) This phase characteristic realizes the three-phase UHV AC transmission line Single-ended precise positioning of short-circuit faults, ranging accuracy is not affected by factors such as transition current, load current, and power system operation mode, and has high ranging accuracy.

附图说明Description of drawings

图1为应用本发明的特高压交流线路输电系统示意图。Fig. 1 is a schematic diagram of a UHV AC line power transmission system applying the present invention.

具体实施方式Detailed ways

下面根据说明书附图对本发明的技术方案做进一步详细表述。The technical solution of the present invention will be further described in detail according to the accompanying drawings.

图1为应用本发明的特高压交流线路输电系统示意图。图1中CVT为电压互感器、CT为电流互感器。保护装置对特高压交流输电线路保护安装处的电压互感器CVT的电压和电流互感器CT的电流波形进行采样得到电压、电流瞬时值。Fig. 1 is a schematic diagram of a UHV AC line power transmission system applying the present invention. In Fig. 1, CVT is a voltage transformer, and CT is a current transformer. The protection device samples the voltage of the voltage transformer CVT and the current waveform of the current transformer CT at the protection installation place of the UHV AC transmission line to obtain the instantaneous values of voltage and current.

保护装置对采样得到的电压、电流瞬时值利用傅里叶算法计算特高压交流输电线路正常运行时的三相电压和三相电流其中，φαβ＝ABC、BCA、CAB相。The protection device uses the Fourier algorithm to calculate the three-phase voltage of the UHV AC transmission line in normal operation on the sampled instantaneous values of voltage and current and three-phase current Among them, φαβ=ABC, BCA, CAB phase.

保护装置对采样得到的电压、电流瞬时值利用傅里叶算法计算特高压交流输电线路三相短路故障后的三相电压和三相电流零序电流其中，φαβ＝ABC、BCA、CAB相。The protection device uses the Fourier algorithm to calculate the three-phase voltage after the three-phase short-circuit fault of the UHV AC transmission line on the instantaneous value of the voltage and current obtained by sampling. and three-phase current Zero sequence current Among them, φαβ=ABC, BCA, CAB phase.

保护装置选取故障距离初始值为l_x，计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的αβ相间电压其中，Z_c1为特高压交流输电线路正序波阻抗；γ₁为特高压交流输电线路正序传播系数；φαβ＝ABC、BCA、CAB相；th(.)为双曲正切函数。The protection device selects the initial value of the fault distance as l_x , and calculates the αβ phase-to-phase voltage at a point l_x away from the protection installation of the UHV AC transmission line after the three-phase short-circuit fault of the UHV AC transmission line Among them, Z_c1 is the positive sequence wave impedance of the UHV AC transmission line; γ₁ is the positive sequence propagation coefficient of the UHV AC transmission line; φαβ=ABC, BCA, CAB phase; th(.) is the hyperbolic tangent function.

计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的φ相电压其中，Z₀为特高压交流输电线路保护安装处的系统零序等值阻抗；γ₁、γ₀分别为特高压交流输电线路正序、零序传播系数；Z_c1、Z_c0分别为特高压交流输电线路正序、零序波阻抗；$k\left(l_x\right)=\frac{Z_{0}ch\left({\mathrm{\γ}}_0{l}_x\right)+Z_{c0}sh\left({\mathrm{\γ}}_0{l}_x\right)-Z_{0}ck\left({\mathrm{\γ}}_1{l}_x\right)}{Z_{c1}sh\left({\mathrm{\γ}}_1{l}_x\right)}-1,$为距离特高压交流输电线路保护安装处l_x点的零序补偿系数；th(.)为双曲正切函数；ch(.)为双曲余弦函数；sh(.)为双曲正弦函数。Calculate the φ-phase voltage at a point l_x away from the UHV AC transmission line protection installation after a three-phase short-circuit fault on the UHV AC transmission line Among them, Z₀ is the zero-sequence equivalent impedance of the system where the UHV AC transmission line protection is installed; γ₁ and γ₀ are the positive-sequence and zero-sequence propagation coefficients of the UHV AC transmission line respectively; Z_c1 and Z_c0 are the UHV Positive-sequence and zero-sequence wave impedance of AC transmission lines;$k\left(l_x\right)=\frac{Z_{0}ch\left({\mathrm{\γ}}_0{l}_x\right)+Z_{c0}\mathrm{the\; s}h\left({\mathrm{\γ}}_0{l}_x\right)-Z_{0}ck\left({\mathrm{\γ}}_1{l}_x\right)}{Z_{c1}\mathrm{the\; s}h\left({\mathrm{\γ}}_1{l}_x\right)}-1,$ is the zero-sequence compensation coefficient of a point l_x away from the UHV AC transmission line protection installation; th(.) is a hyperbolic tangent function; ch(.) is a hyperbolic cosine function; sh(.) is a hyperbolic sine function.

计算${\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{U}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{U}}_{\mathrm{\β}\[0\]}$领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right).$calculate${\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{u}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{u}}_{\mathrm{\β}\[0\]}$ take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right).$

计算领先的相角$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right).$calculate take the lead phase angle of$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right).$

故障距离l_x以固定步长Δl递增，依次计算特高压交流输电线路上每一点处领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$和领先的相角$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right);$直至特高压交流输电线路全长。The fault distance l_x is incremented with a fixed step size Δl, and the fault distance at each point on the UHV AC transmission line is calculated sequentially take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$ and take the lead phase angle of$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right);$ Up to the full length of the UHV AC transmission line.

保护装置选取特高压交流输电线路上某一l_x点的落在(-90°90°)和$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right);$落在(-90°90°)，且其相邻一下个l_x+Δl的$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$落在(90°270°)和落在(90°270°)，则这两个点的中间位置即为特高压交流输电线路三相短路故障点。The protection device selects a certain l_x point on the UHV AC transmission line falls on (-90°90°) and$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right);$ Falls on (-90°90°), and it is adjacent to the next l_x +Δl$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$ falls on (90°270°) and (90°270°), the middle of these two points is the three-phase short-circuit fault point of the UHV AC transmission line.

本发明方法采用分布参数精确描述特高压交流输电线路电压电流传输的物理过程，具有天然的抗分布电容电流的能力。The method of the invention uses distribution parameters to accurately describe the physical process of voltage and current transmission of UHV AC transmission lines, and has natural ability to resist distributed capacitance current.

本发明方法利用特高压交流输电线路三相短路故障点前后，特高压交流输电线路正常运行时保护安装处的相间电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的相间电压的相角由(-90°90°)突变进入(90°270°)，且特高压交流输电线路正常运行时保护安装处另一相电压领先特高压交流输电线路三相短路故障后特高压交流输电线路三相短路故障点前后的另一相电压的相角也由(-90°90°)突变进入(90°270°)这一相位特性实现特高压交流输电线路三相短路故障的单端精确定位，测距精度不受过渡电流、负荷电流和电力系统运行方式等因素的影响，具有很高的测距精度。The method of the present invention utilizes before and after the three-phase short-circuit fault point of the UHV AC transmission line, and when the UHV AC transmission line is in normal operation, the phase-to-phase voltage at the protection installation place is ahead of the three-phase short-circuit fault of the UHV AC transmission line after the UHV AC transmission line three-phase short-circuit fault The phase angle of the phase-to-phase voltage before and after the point changes from (-90°90°) to (90°270°), and when the UHV AC transmission line is in normal operation, the other phase voltage at the protection installation is ahead of the three-phase short circuit of the UHV AC transmission line After the fault, the phase angle of the other phase voltage before and after the three-phase short-circuit fault point of the UHV AC transmission line also changes suddenly from (-90°90°) to (90°270°) This phase characteristic realizes the three-phase UHV AC transmission line Single-ended precise positioning of short-circuit faults, ranging accuracy is not affected by factors such as transition current, load current, and power system operation mode, and has high ranging accuracy.

以上所述仅为本发明的较佳具体实施例，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，可轻易想到的变化或替换，都应涵盖在本发明的保护范围之内。The above descriptions are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto, any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention , should be covered within the protection scope of the present invention.

Claims (1)

Translated fromChinese

1.基于单端电气量特高压交流输电线路三相短路故障测距方法，其特征在于，包括如下依序步骤：1. The three-phase short-circuit fault location method of UHV AC transmission line based on single-ended electrical quantity, is characterized in that, comprises the following sequential steps:(1)保护装置测量特高压交流输电线路正常运行时的三相电压和三相电流其中，φαβ＝ABC、BCA、CAB相；(1) The protection device measures the three-phase voltage of the UHV AC transmission line during normal operation and three-phase current Among them, φαβ=ABC, BCA, CAB phase;(2)保护装置测量特高压交流输电线路三相短路故障后的三相电压和三相电流零序电流其中，φαβ＝ABC、BCA、CAB相；(2) The protection device measures the three-phase voltage after the three-phase short-circuit fault of the UHV AC transmission line and three-phase current Zero sequence current Among them, φαβ=ABC, BCA, CAB phase;(3)保护装置选取故障距离初始值为l_x，计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的αβ相间电压其中，Z_c1为特高压交流输电线路正序波阻抗；γ₁为特高压交流输电线路正序传播系数；φαβ＝ABC、BCA、CAB相；th(.)为双曲正切函数；(3) The protection device selects the initial value of the fault distance as l_x , and calculates the αβ phase-to-phase voltage at a point l_x away from the protection installation of the UHV AC transmission line after the three-phase short-circuit fault of the UHV AC transmission line Among them, Z_c1 is the positive sequence wave impedance of the UHV AC transmission line; γ₁ is the positive sequence propagation coefficient of the UHV AC transmission line; φαβ=ABC, BCA, CAB phase; th(.) is the hyperbolic tangent function;(4)计算特高压交流输电线路三相短路故障后距离特高压交流输电线路保护安装处l_x点的φ相电压其中，Z0为特高压交流输电线路保护安装处的系统零序等值阻抗；γ₁、γ₀分别为特高压交流输电线路正序、零序传播系数；Z_c1、Z_c0分别为特高压交流输电线路正序、零序波阻抗；为距离特高压交流输电线路保护安装处l_x点的零序补偿系数；th(.)为双曲正切函数；ch(.)为双曲余弦函数；sh(.)为双曲正弦函数；(4) Calculate the φ-phase voltage at the point l_x away from the UHV AC transmission line protection installation after the three-phase short-circuit fault of the UHV AC transmission line Among them, Z0 is the zero-sequence equivalent impedance of the system where the UHV AC transmission line protection is installed; γ₁ and γ₀ are the positive-sequence and zero-sequence propagation coefficients of the UHV AC transmission line respectively; Z_c1 and Z_c0 are the UHV AC Positive-sequence and zero-sequence wave impedance of transmission lines; is the zero-sequence compensation coefficient of a point l_x away from the UHV AC transmission line protection installation; th(.) is a hyperbolic tangent function; ch(.) is a hyperbolic cosine function; sh(.) is a hyperbolic sine function;(5)计算${\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{U}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{U}}_{\mathrm{\β}\[0\]}$领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right);$(5) calculation${\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{u}}_{\mathrm{\β}\[0\]}$ take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right);$(6)计算领先的相角$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right);$(6) calculation take the lead phase angle of$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right);$(7)故障距离l_x以固定步长Δl递增，返回步骤(3)，依次计算特高压交流输电线路上每一点处${\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\·}{U}}_{\mathrm{\α}\[0\]}-{\stackrel{\·}{U}}_{\mathrm{\β}\[0\]}$领先的相角$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$和领先的相角直至特高压交流输电线路全长；(7) The fault distance l_x increases with a fixed step size Δl, return to step (3), and calculate the distance at each point on the UHV AC transmission line${\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}={\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\α}\[0\]}-{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\β}\[0\]}$ take the lead phase angle of$\mathrm{\ϵ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}}\left(l_x\right)}\right)$ and take the lead phase angle of Up to the full length of the UHV AC transmission line;(8)保护装置选取特高压交流输电线路上某一l_x点的落在(-90°90°)和$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\φ}}\left(l_x\right)}\right)$落在(-90°90°)，且其相邻一下个l_x+Δl的$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{U}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$落在(90°270°)和落在(90°270°)，则这两个点的中间位置即为特高压交流输电线路三相短路故障点。(8) The protection device selects a certain_lx point on the UHV AC transmission line falls on (-90°90°) and$\mathrm{\λ}\left(l_x\right)=Arg\left(\frac{{\stackrel{\&Center\; Dot;}{u}}_{\mathrm{\φ}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\φ}}\left(l_x\right)}\right)$ Falls on (-90°90°), and it is adjacent to the next l_x +Δl$\mathrm{\ϵ}(l_x+\mathrm{\Δ}l)=Arg\left(\frac{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}\[0\]}}{{\stackrel{\·}{u}}_{\mathrm{\α}\mathrm{\β}}(l_x+\mathrm{\Δ}l)}\right)$ falls on (90°270°) and (90°270°), the middle of these two points is the three-phase short-circuit fault point of the UHV AC transmission line.