Non-communication protection of coal mine DC distribution lines based on transient current derivation
-
摘要: 煤矿直流供配电线路故障电流具有幅值大、上升率高的特征，是威胁供电系统安全稳定的重要因素。利用直流配电系统电气特征实现故障识别的方法较少考虑保护设备的实际情况，难以处理设备误差及扰动，不满足继电保护的可靠性要求；而基于电力电子变换器的主动保护方法则较少利用故障电气量信息，仅依靠设备动作特性实现故障切除，往往不能满足继电保护的速动性要求。针对上述问题，提出一种基于暂态电流导数的煤矿直流配电线路无通道保护方案。将直流侧并联电容放电电流的二阶导数作为保护加速判据，若满足加速判据则启动加速动作，若不满足加速判据则按照断路器既定延时动作。故障发生时，电流均指向故障点，则可利用功率流向的变化初步判断故障方向，构成无通道保护，使故障线路两端断路器加速跳开，从而缩短故障切除时间。仿真结果表明，在不同故障发生位置、过渡电阻及故障类型条件下，若加速动作能够有效启动，则基于暂态电流导数的煤矿直流配电线路无通道保护方案可快速切除故障，减少故障时间；若加速动作不能启动，保护方案也能按照既定延时配合实现故障类型和区段的确定并切除故障。Abstract: The fault current of coal mine DC power supply and distribution lines has the features of large amplitude and high rise rate, which is an important factor threatening the safety and stability of the power supply system. The method of using electrical features of DC distribution systems to achieve fault recognition rarely considers the actual situation of protective equipment. It makes it difficult to handle equipment errors and disturbances, and it does not meet the reliability requirements of relay protection. The active protection methods based on power electronic converters rarely utilize fault electrical information and rely solely on equipment action features to achieve fault removal. It often fails to meet the quick action requirements of relay protection. In order to solve the above problems, a non-communication protection scheme for coal mine DC distribution lines based on transient current derivation is proposed. The second derivative of the discharge current of the parallel capacitor on the DC side is used as the protection acceleration criterion. If the acceleration criterion is met, it will start the acceleration action. If the acceleration criterion is not met, it will act according to the established delay of the circuit breaker. When a fault occurs, the current is directed towards the fault point. The change in power flow direction can be used to preliminarily determine the direction of the fault, forming a non-communication protection. It will accelerate the tripping of the circuit breakers at both ends of the fault line, thereby shortening the fault removal time. The simulation results show that under different fault positions, transition resistors, and fault types, if the acceleration action can effectively start, the non-communication protection scheme of coal mine DC distribution lines based on transient current derivation can quickly remove faults and reduce fault time. If the acceleration action cannot be started, the protection scheme can also cooperate with the established delay to determine the fault type and section and remove the fault.
-
-
![]()
图 1 直流配电系统单极接地故障时的等效电路
Figure 1. Equivalent circuit of DC distribution system with monopole to earth fault
![]()
图 2 直流配电系统极间故障时的等效电路
Figure 2. Equivalent circuit of DC distribution system with pole to pole fault
![]()
图 4 故障位置与电容放电电流二阶导数的关系
Figure 4. Relationship between fault location and the second derivation of capacitance discharge current
![]()
图 5 双端供电型直流配电线路保护
Figure 5. Double end power supply type DC distribution line protection
![]()
图 6 双端直流配电线路无通道保护原理
Figure 6. The principle of non-communication protection in double end DC distribution network
![]()
图 7 直流配电线路无通道保护流程
Figure 7. Flow of non-communication protection of DC distribution line
![]()
图 8 双端±10 kV直流配电系统仿真模型
Figure 8. Simulation model of dual terminal ±10 kV DC distribution system
![]()
图 9 线路末端极间故障时电容放电电流二阶导数变化曲线
Figure 9. Second derivative variation curves of capacitor discharge current during pole to pole fault at the line end
![]()
图 11 线路末端单极接地故障时电容电流二阶导数变化曲线
Figure 11. The second derivative variation curves of capacitor discharge current during monopole to earth fault at the line end
表 1 简化电路参数计算
Table 1 Calculation of simplified circuit parameters
故障类型 R L C 极间故障（L−L） 2xr0+Rf 2xl0 C0/2 接地故障（L−G） xr0+Rf xl0 C0 
下载: 导出CSV
表 2 放电电流的一阶导数与二阶导数差异
Table 2 Difference between the first and the second derivative of discharge current
过渡电阻/Ω b1 b2 b'1 b'2 0.5 1.255 1.412 1.219 1.858 1 1.255 1.464 1.199 1.699 3 1.256 1.524 1.114 1.47 5 1.257 1.541 1.021 1.451
下载: 导出CSV
表 3 不同故障类型下的直流线路电流差异
Table 3 Current differences in DC line under different fault types
故障类型 ip+in |ip|−|in| 正极接地故障 非0 大于0 负极接地故障 非0 小于0 极间故障 0 0
下载: 导出CSV
表 4 极间故障时各级线路保护加速判据
Table 4 Acceleration criteria for line protection at all levels during pole to pole fault
保护装置 保护加速判据/108 原始值的绝对值 整定值 P4 2.380 2.860 P3 0.699 0.838
下载: 导出CSV
表 5 单极接地故障时各级线路保护加速判据
Table 5 Acceleration criteria for line protection at all levels during monopole to earth fault
保护装置 保护加速判据/108 原始值的绝对值 整定值 P4 7.21 8.65 P3 2.43 2.91
下载: 导出CSV
表 6 单级接地故障时的保护动作情况
Table 6 Protection action during monopole to earth fault
过渡电阻/Ω 故障距离/km 加速动作时刻/s 故障切除
总时间/ms故障类型
判断结果P1 P2 0.2 0.03 1.003 — 3 L−G 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 1 0.03 1.003 — 3 L−G 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 3 0.03 1.003 — 3 L−G 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 5 0.03 1.003 — 3 L−G 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14
下载: 导出CSV
表 7 极间故障时的保护动作情况
Table 7 Protection action during pole to pole fault
过渡电阻/Ω 故障距离/km 加速动作时刻/s 故障切除
总时间/ms故障类型
判断结果P1 P2 0.2 0.03 1.003 — 3 L−L 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 1 0.03 1.003 — 3 L−L 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 3 0.03 1.003 — 3 L−L 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14 5 0.03 1.003 — 3 L−L 1.50 1.003 — 3 2.97 — — 21 3.03 — 1.003 7 4.50 — 1.003 7 5.97 — — 14
下载: 导出CSV
-
[1] 刘波. 煤矿智能化供电系统的防越级跳闸与远程漏试应用[J]. 工矿自动化,2021,47(增刊1):85-87. LIU Bo. Application of anti override trip and remote leakage test in coal mine intelligent power supply system[J]. Industry and Mine Automation,2021,47(S1):85-87.
[2] 贾新立. 煤矿供电系统穿越性故障识别与隔离方案研究[J]. 中国煤炭,2017,43(3):89-92,108. JIA Xinli. Research on through fault recognition and isolation scheme for coal mine power supply system[J]. China Coal,2017,43(3):89-92,108.
[3] 宋国兵,陶然,李斌,等. 含大规模电力电子装备的电力系统故障分析与保护综述[J]. 电力系统自动化,2017,41(12):2-12. SONG Guobing,TAO Ran,LI Bin,et al. Survey of fault analysis and protection for power system with large scale power electronic equipments[J]. Automation of Electric Power Systems,2017,41(12):2-12.
[4] 曾嘉思,徐习东,赵宇明. 交直流配电网可靠性对比[J]. 电网技术,2014,38(9):2582-2589. ZENG Jiasi,XU Xidong,ZHAO Yuming. Reliability comparison of AC and DC distribution network[J]. Power System Technology,2014,38(9):2582-2589.
[5] 乔立华,陶然,宋国兵,等. 直流线路边界特性保护综述[J]. 电力系统保护与控制,2019,47(19):179-186. QIAO Lihua,TAO Ran,SONG Guobing,et al. A summary of the boundary characteristics used in DC system relay protection[J]. Power System Protection and Control,2019,47(19):179-186.
[6] 王国钰,范春菊,李潇. 伪双极接线不同接地方式下直流配电线路故障选极方案[J]. 电网技术,2022,46(9):3570-3579. WANG Guoyu,FAN Chunju,LI Xiao. Fault pole selection of DC distribution lines under pseudo-bipolar wiring with different grounding modes[J]. Power System Technology,2022,46(9):3570-3579.
[7] 高仁栋,吴在军,范文超,等. 基于电流微分初始值的VSC直流配电系统线路故障定位方法[J]. 电力自动化设备,2018,38(2):27-33. GAO Rendong,WU Zaijun,FAN Wenchao,et al. Line fault location method of VSC-based DC distribution system based on initial current differential value[J]. Electric Power Automation Equipment,2018,38(2):27-33.
[8] 和敬涵,周琳,罗国敏,等. 基于单端电气量的多端柔性直流配电系统暂态保护[J]. 电力自动化设备,2017,37(8):158-165. HE Jinghan,ZHOU Lin,LUO Guomin,et al. Transient protection based on single-end electrical signals for multi-terminal flexible DC distribution system[J]. Electric Power Automation Equipment,2017,37(8):158-165.
[9] 高淑萍,吕宇星,宋国兵,等. 利用改进VMD突变能量的直流配电网保护方法[J/OL]. 西安交通大学学报:1-11[2023-09-13]. http://kns.cnki.net/kcms/detail/61.1069.t.20221213.1740.003.html. GAO Shuping,LYU Yuxing,SONG Guobing,et al. DC distribution network protection method using improved VMD sudden change energy[J/OL]. Journal of Xi'an Jiaotong University:1-11[2023-09-13]. http://kns.cnki.net/kcms/detail/61.1069.t.20221213.1740.003.html.
[10] 贾科,李猛,毕天姝,等. 柔性直流配电线路能量分布差动保护[J]. 电网技术,2017,41(9):3058-3065. JIA Ke,LI Meng,BI Tianshu,et al. Energy distribution-based differential protection for VSC-DC distribution lines[J]. Power System Technology,2017,41(9):3058-3065.
[11] 肖磊石,盛超,骆潘钿,等. 基于电阻型超导限流器的直流线路纵联保护方法[J]. 广东电力,2020,33(8):11-17. XIAO Leishi,SHENG Chao,LUO Pandian,et al. Pilot protection method of DC line based on resistance superconducting fault current limiter[J]. Guangdong Electric Power,2020,33(8):11-17.
[12] 李威,吴学光,常彬,等. 基于电压变化率故障检测的高压直流断路器保护策略[J]. 电网技术,2019,43(2):554-565. LI Wei,WU Xueguang,CHANG Bin,et al. Research on protection strategy of HVDC circuit breaker based on voltage change rate fault detection[J]. Power System Technology,2019,43(2):554-565.
[13] 彭发喜,汪震,邓银秋,等. 混合式直流断路器在柔性直流电网中应用初探[J]. 电网技术,2017,41(7):2092-2098. PENG Faxi,WANG Zhen,DENG Yinqiu,et al. Potentials of hybrid HVDC circuit breakers'application to MMC-HVDC grid[J]. Power System Technology,2017,41(7):2092-2098.
[14] 董恩源,杜广波,邹积岩,等. 新型直流断路器在短路故障保护中的应用[J]. 电工技术杂志,2003(11):29-31. DONG Enyuan,DU Guangbo,ZOU Jiyan,et al. Application of intelligent operating system in DC breakers[J]. Electrotechnical Journal,2003(11):29-31.
[15] 郑涛,吴琼,吕文轩,等. 基于主动限流控制的直流配电网保护及故障隔离方案[J]. 电力系统自动化,2020,44(5):114-121. ZHENG Tao,WU Qiong,LYU Wenxuan,et al. Protection and fault isolation scheme based on active current-limiting control for DC distribution network[J]. Automation of Electric Power Systems,2020,44(5):114-121.
[16] 吴鸣,刘海涛,陈文波,等. 中低压直流配电系统的主动保护研究[J]. 中国电机工程学报,2016,36(4):891-899. WU Ming,LIU Haitao,CHEN Wenbo,et al. Research on active protection for MV/LV DC distribution system[J]. Proceedings of the CSEE,2016,36(4):891-899.
[17] 姜舒婷,齐磊,崔翔,等. 含潮流控制器的直流电网潮流计算方法[J]. 电网技术,2015,39(7):1793-1799. JIANG Shuting,QI Lei,CUI Xiang,et al. Power flow algorithm method for DC grid with power controller[J]. Power System Technology,2015,39(7):1793-1799.
[18] 束洪春,安娜,代月,等. 基于电流上升速率的柔性直流环网输电线路反时限保护[J]. 电力系统自动化,2023,47(6):206-215. SHU Hongchun,AN Na,DAI Yue,et al. Inverse-time protection for flexible DC transmission lines in ring network based on current rising rate[J]. Automation of Electric Power Systems,2023,47(6):206-215.
[19] 贺家李,宋从矩,李永丽,等. 电力系统继电保护原理[M]. 北京:中国电力出版社,2004. HE Jiali,SONG Congju,LI Yongli,et al. Principles of relay protection in power systems[M]. Beijing:China Electric Power Press,2004.
[20] BO Z Q,DONG X Z,CAUNCE B R J. Accelerated protection of distribution systems with tapped off loads[J]. IEE Proceedings-Generation,Transmission and Distribution,2004,151(4):461-468. DOI: 10.1049/ip-gtd:20040696
[21] BO Z Q,DONG X Z,CAUNCE B R J,et al. Adaptive noncommunication protection of double-circuit line systems[J]. IEEE Transactions on Power Delivery,2003,18(1):43-49. DOI: 10.1109/TPWRD.2002.803748
[22] 范兴明,李涛,张鑫. 中高压直流断路器的研究与应用[J/OL]. 高电压技术:1-16 [2023-09-13]. DOI: 10.13336/j.1003-6520.hve.20230696. FAN Xingming,LI Tao,ZHANG Xin. Research and application of medium and high voltage DC circuit breaker[J/OL]. High Voltage Engineering:1-16[2023-09-13]. DOI: 10.13336/j.1003-6520.hve.20230696.
计量
- 文章访问数: 506
- HTML全文浏览量: 45
- PDF下载量: 20
