With the rapid development of urban economy, distribution network construction of city is lagging behind the increment of load, and low-voltage problem has become the main complaints of the power users. Based on Pytho...With the rapid development of urban economy, distribution network construction of city is lagging behind the increment of load, and low-voltage problem has become the main complaints of the power users. Based on Python [1] scripting language, this paper develops a piece of software which can provide a friendly human-machine experience for the user, calculate the voltage of the power distribution area and propose corresponding control measures, then the paper takes the actual power distribution area to verify its effectiveness.展开更多
Low-voltage distribution systems in our country are mostly used in agricultural loads and household loads. The value and using time of these kinds of loads are uncontrollable, which lead to the three-phase imbalance i...Low-voltage distribution systems in our country are mostly used in agricultural loads and household loads. The value and using time of these kinds of loads are uncontrollable, which lead to the three-phase imbalance in low-voltage distribution system, and seriously affect the quality of power supply. A new type of the commutation system and an improved quantum genetic algorithm (IQGA) are proposed in the paper. At last, the rationality and the efficiency of the method are verified by a practical example.展开更多
Accurate topological information is crucial in supporting the coordinated operational requirements of source-load-storage in low-voltage distribution networks.Comprehensive coverage of smart meters provides a database...Accurate topological information is crucial in supporting the coordinated operational requirements of source-load-storage in low-voltage distribution networks.Comprehensive coverage of smart meters provides a database for low-voltage topology identification(LVTI).However,because of electricity theft,power line commu-nication crosstalk,and interruption of communication,the measurement data may be distorted.This can seriously affect the performance of LVTI methods.Thus,this paper defines hidden errors and proposes an LVTI method based on layer-by-layer stepwise regression.In the first step,a multi-linear regression model is developed for consumer-branch connectivity identification based on the energy conservation principle.In the second step,a significance factor based on the t-test is proposed to modify the identification results by considering the hidden errors.In the third step,the regression model and significance threshold parameters are iteratively updated layer by layer to improve the recall rate of the final identification results.Finally,simulations of a test system with 63 users are carried out,and the practical application results show that the proposed method can guarantee over 90%precision under the influence of hidden errors.展开更多
随着分布式光伏发电技术的广泛应用,光伏并网给传统配电网继电保护系统引入了新的挑战。例如,光伏电源并网时会使原网络的潮流发生改变,使电网的安全可靠运行受到影响。现有的继电保护方案无法应用于含光伏系统的网络。本研究提出了一...随着分布式光伏发电技术的广泛应用,光伏并网给传统配电网继电保护系统引入了新的挑战。例如,光伏电源并网时会使原网络的潮流发生改变,使电网的安全可靠运行受到影响。现有的继电保护方案无法应用于含光伏系统的网络。本研究提出了一种基于低电压穿越(Low Voltage Ride-Through,LVRT)能力的光伏电源继电保护增强技术,通过实时监测与控制系统,优化继电保护策略,以应对光伏并网带来的挑战。研究结果表明,所提增强技术能有效提升配电网的保护性能和系统稳定性,为光伏并网的配电网继电保护提供有效的解决方案。展开更多
文摘With the rapid development of urban economy, distribution network construction of city is lagging behind the increment of load, and low-voltage problem has become the main complaints of the power users. Based on Python [1] scripting language, this paper develops a piece of software which can provide a friendly human-machine experience for the user, calculate the voltage of the power distribution area and propose corresponding control measures, then the paper takes the actual power distribution area to verify its effectiveness.
文摘Low-voltage distribution systems in our country are mostly used in agricultural loads and household loads. The value and using time of these kinds of loads are uncontrollable, which lead to the three-phase imbalance in low-voltage distribution system, and seriously affect the quality of power supply. A new type of the commutation system and an improved quantum genetic algorithm (IQGA) are proposed in the paper. At last, the rationality and the efficiency of the method are verified by a practical example.
基金supported by the National Natural Sci-ence Foundation of China(No.52177085)Science and Technology Planning Project of Guangzhou(No.202102021208).
文摘Accurate topological information is crucial in supporting the coordinated operational requirements of source-load-storage in low-voltage distribution networks.Comprehensive coverage of smart meters provides a database for low-voltage topology identification(LVTI).However,because of electricity theft,power line commu-nication crosstalk,and interruption of communication,the measurement data may be distorted.This can seriously affect the performance of LVTI methods.Thus,this paper defines hidden errors and proposes an LVTI method based on layer-by-layer stepwise regression.In the first step,a multi-linear regression model is developed for consumer-branch connectivity identification based on the energy conservation principle.In the second step,a significance factor based on the t-test is proposed to modify the identification results by considering the hidden errors.In the third step,the regression model and significance threshold parameters are iteratively updated layer by layer to improve the recall rate of the final identification results.Finally,simulations of a test system with 63 users are carried out,and the practical application results show that the proposed method can guarantee over 90%precision under the influence of hidden errors.
文摘随着分布式光伏发电技术的广泛应用,光伏并网给传统配电网继电保护系统引入了新的挑战。例如,光伏电源并网时会使原网络的潮流发生改变,使电网的安全可靠运行受到影响。现有的继电保护方案无法应用于含光伏系统的网络。本研究提出了一种基于低电压穿越(Low Voltage Ride-Through,LVRT)能力的光伏电源继电保护增强技术,通过实时监测与控制系统,优化继电保护策略,以应对光伏并网带来的挑战。研究结果表明,所提增强技术能有效提升配电网的保护性能和系统稳定性,为光伏并网的配电网继电保护提供有效的解决方案。
