Parallel operation of inverters for distributed photovoltaic power supply system

With the wide application of electric drive equipment and variable frequency load, the power supply system based on the DC grid has attracted much attention because of its high energy density and simple control, and the operation mode of rectifier AC synchronous generators operating in parallel is often adopted. The available topology structures of the rectifier permanent magnet (PM) generator sets are analyzed in this paper, the parallel operation principle of uncontrolled rectifier PM generator sets is analyzed in theory. The parallel operation characteristics of the generator sets are summarized when the voltage-stabilizing and power balanced measures are not taken, and the influence factors of power balancing among parallel operation generators are analyzed. The power-balanced method of rectifier generator sets operating in parallel based on a master-slave control strategy is proposed, which can realize power balanced with the closed-loop control of the DC side output current. The simulation and experiment results show that the proposed method can realize the power balanced control of rectifier generator sets operating in parallel well. The output power of each generator set can be distributed according to capacity. The rationalization proposal of how to matching generators’ parameters in the power supply system of rectifier PM generator sets operating in parallel is given.

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The Study of the Effectiveness of Strengthening the Traction Power Supply System of the Northern Route of the Eastern Polygon of the Russian Railroads

Journal of Physics Conference Series ◽

10.1088/1742-6596/2096/1/012153 ◽

2021 ◽

Vol 2096 (1) ◽

pp. 012153

Author(s):

E Yu Puzina ◽

I A Khudonogov

Keyword(s):

Mathematical Simulation ◽

Power Supply ◽

Power Supply System ◽

Simulation Method ◽

Supply System ◽

Parallel Operation ◽

Software Application ◽

Traction Power Supply System ◽

Traction Power Supply ◽

Traction Power

Abstract The train-handling capacity of the limiting section of the traction power supply system of the Northern route of the Eastern polygon of the Eastern Siberian Railroad has been estimated, taking into account the prospective amount of traffic for 2025. Due to insufficient train-handling capacity of the section and inconsistency of voltage level in the overhead system, the parameters of traction power supply system operation mode were studied using the mathematical simulation method in the Fazonord software application and the mathematical simulation method in the Kortes software application using various technical means of amplification. The simulation results allowed us to determine the most optimal amplification methods that meet the task set. It was proved that the method of increasing the transmitted power from 220 kV power line to 110 kV line through the autotransformer installed for their connection at the new traction substation of the limiting long section corresponds to the purpose of ensuring the required trainhandling capacity of the limiting section in the best possible way, taking into account the prospects for development of both the external power supply system and the system of traction power supply. At one of the traction substations of the section under study it is required to install an additional power transformer for parallel operation. The specified combination of technical amplification means brings the parameters of traction power supply system into compliance with the requirements.

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