Method for determining commutation failure of multi-infeed direct current power transmission system

Abstract

The invention provides a method for determining commutation failure of a multi-infeed direct current power transmission system. The method is characterized by comprising the steps of calculating the extinction angle of an inverter station in the system in case of three-phase short-circuit grounding and single-phase short-circuit grounding of each node based on a nodal impedance matrix and by virtue of a node voltage interaction factor, and determining whether the direct current system fails in commutation with a critical extinction angle as the criterion. Besides, the calculation results of all the nodes are integrated, and a three-phase critical failure impedance boundary and a single-phase critical failure impedance boundary are delimited on a network topology, respectively. The minimum extinction angle is taken as the determination criterion of the method for the commutation failure, and an alternating current system area causing the commutation failure of the direct current system during a fault can be determined quickly and accurately through simple calculation by virtue of the critical failure impedance boundaries, and the accuracy of the determination method is improved while the determination process of the commutation failure is simplified. The influence, caused by a fault of an alternating current system, on the direct current system can be determined and analyzed clearly and visually.

Description

technical field

[0001] The invention belongs to the technical field of power transmission, and relates to a method for judging phase commutation failure of a multi-feed direct current transmission system. Background technique

[0002] In a multi-infeed DC transmission system, a fault in the AC system at the receiving end may cause commutation failure in the inverter station near the fault point, or even lead to simultaneous or sequential commutation failures in multiple DC lines. If the normal commutation function cannot be restored, it will cause catastrophic consequences of large-scale power outages and seriously threaten the safe and stable operation of the power grid. However, not all AC system failures can cause DC system commutation failure, which depends on the grid structure and operating characteristics of the system. With the rapid construction and continuous commissioning of DC transmission systems, it is of great theoretical research significance to establish an...

Examples

Embodiment Construction

[0055] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0056] see figure 1 , a multi-infeed direct current transmission system commutation failure judging method of the present invention comprises five steps:

[0057] 1) Use power system simulation software or power system power flow calculation program to calculate the AC and DC system power flow, and determine the node voltage values ​​in each network.

[0058] 2) According to the system network parameters and grid structure, build generators, lines, transformers, loads and DC system models, establish network impedance analysis data, and generate system node impedance matrix.

[0059] 3) Assuming that the converter bus node of the DC inverter station is j, when a three-phase short-circuit fault occurs on the bus i in the AC system, the node voltage interaction factor is introduced to calculate the voltage drop value of the converter bus node of ...

technical field

[0001] The invention belongs to the technical field of power transmission, and relates to a method for judging phase commutation failure of a multi-feed direct current transmission system. Background technique

[0002] In a multi-infeed DC transmission system, a fault in the AC system at the receiving end may cause commutation failure in the inverter station near the fault point, or even lead to simultaneous or sequential commutation failures in multiple DC lines. If the normal commutation function cannot be restored, it will cause catastrophic consequences of large-scale power outages and seriously threaten the safe and stable operation of the power grid. However, not all AC system failures can cause DC system commutation failure, which depends on the grid structure and operating characteristics of the system. With the rapid construction and continuous commissioning of DC transmission systems, it is of great theoretical research significance to establish an...

Examples

Embodiment Construction

[0055] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0056] see figure 1 , a multi-infeed direct current transmission system commutation failure judging method of the present invention comprises five steps:

[0057] 1) Use power system simulation software or power system power flow calculation program to calculate the AC and DC system power flow, and determine the node voltage values ​​in each network.

[0058] 2) According to the system network parameters and grid structure, build generators, lines, transformers, loads and DC system models, establish network impedance analysis data, and generate system node impedance matrix.

[0059] 3) Assuming that the converter bus node of the DC inverter station is j, when a three-phase short-circuit fault occurs on the bus i in the AC system, the node voltage interaction factor is introduced to calculate the voltage drop value of the converter bus node of ...

Images