Line voltage based earth-free power distribution network three-phase power flow calculation method

Abstract

The invention discloses a line voltage based earth-free power distribution network three-phase power flow calculation method. Structural data and parameter information of the network, control information of PV nodes and node load information are input based on programs through a computer, and the information is initialized; then the node admittance matrix and the jacobian matrix constant term of the network based on the line voltage are calculated; next, a node current unbalance equation of the network unbalance nodes, a power constraint equation of constant current star-shaped load nodes, a general active power constraint equation of the PV nodes and a line voltage amplitude constraint equation are taken into comprehensive consideration; the real and imaginary parts of the respective node line voltages FORMULA as shown in the specification, the real and imaginary parts of the injection current FORMULA as shown in the specification, of the constant current star-shaped load nodes, and the real and imaginary parts of the injection current FORMULA as shown in the specification, of the PV nodes are taken as the state variables; the Newton-Raphson algorithm is adopted based on the injection current ways to calculate the corresponding unbalance amount and the jacobian matrix; and finally the state variables are updated and convergence judgment is carried out to realize the earth-free power distribution network three-phase power flow calculation.

Description

technical field [0001] The invention belongs to the technical field of power system steady-state power flow calculation. Background technique [0002] With the economic development of our country and the continuous improvement of people's living standards, power users have higher and higher requirements for power supply reliability and power quality. As an important part of the power system, the distribution network directly faces the user terminals. Its power flow distribution and operating status will directly affect people's production and life, so it is necessary to study it to obtain accurate operating status. As the basis of distribution system analysis, the three-phase power flow calculation of distribution network is an important means to obtain distribution network status data, and provides basic data for further analysis and calculation of distribution network status estimation, optimal operation, and fault handling. The results directly affect power distribution. ...

AI Technical Summary

Problems solved by technology

[0007] 3) This method considers that the three-phase power of the PQ node cannot be completely independently controlled, that is, the apparent power of each phase cannot be completely known

Therefore, this method cannot accurately calculate the power flow distribution and operating status of the ungrounded distribution network.

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