Fault distance detection method for active power distribution network

Abstract

The invention discloses a fault distance detection method for an active power distribution network, and the method comprises the following steps: first, obtaining the data of an active power distribution network; second, determining each power supply section so as to confirm the troubled section; using the forward-backward sweep method to calculate the injection current of the downstream of the troubled point to the troubled point; calculating the voltage phase amount and the current phase amount at the downstream end of the troubled section and calculating the nominal position of the troubled point; and finally calculating the distance from the troubled point to a transformer substation. In the method of the invention, the distribution-type power supply multi-point accessing is considered, and only through the use of the local voltage and current phase amounts and the synchronous current phase amount of the distribution-type power supply, it is possible to realize the fault distance detection for the active power distribution network. In addition, through the comparison of the current at the two sections of an area section, the positioning of a troubled area section can be realized. Through the calculation of the fault current and the contribution of the downstream current of the fault point to the fault current, the positioning and distance detection for the fault can be realized, making the method suitable for the fault distance detection under the condition of a multi-point distribution-type power supply accessing.

Description

technical field [0001] The invention relates to a fault location method for an active distribution network, belonging to the technical field of distribution network automation. Background technique [0002] Various distributed power sources are continuously connected to the distribution network, and the penetration rate of distributed power sources is also increasing, which makes the fault location technology of the active distribution network one of the key technologies to ensure the reliability and quality of power supply. In the conventional distribution network, the location of the fault section is realized by using the phenomenon that the fault current can be detected at the upstream switch of the fault point but not at the downstream switch of the fault point. However, in the active distribution network where distributed power is highly penetrated, the short-circuit current provided by distributed power may cause the fault current flowing through the downstream switch ...

AI Technical Summary

Problems solved by technology

However, in the active distribution network where distributed power is highly penetrated, the short-circuit current provided by distributed power may cause the fault current flowing through the downstream switch of the fault point to be greater than the overcurrent setting value, resulting in the failure of conventional fault location methods

[0003] Domestic and foreign research results on the impact of distributed power sources on active distribution network fault location and corresponding solutions are mainly focused on fault location using impedance method, synchronous machine approximate model method, or using synchronous voltage and current phasor method. At present, the above-mentioned synchrophasor-based positioning method needs to install a synchrophasor measurement device and a high-speed data acquisition system at the switch, and realize the location of the fault section by comparing the phasor difference between the two sections of the line and the mutual communication between the intelligent terminals. However, it is impossible to determine the distance of the fault. These methods increase the computational workload, and only consider the case of only one distributed power supply in the system, and do not consider the multi-point access of distributed power supply

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