Method and system for monitoring real-time critical short-circuit ratio of high-proportion new energy power system

Abstract

The application discloses a high-proportion new energy power system critical short-circuit ratio real-time monitoring method and system and belongs to the technical field of voltage stability analysis. The method comprises the following steps: determining a real-time short-circuit ratio index for quantitatively evaluating the voltage support strength of the high-proportion new energy power system; determining a real-time critical short-circuit ratio index for distinguishing the static stability limit of the voltage support strength of the high-proportion new energy power system; obtaining a static stability margin index for distinguishing the voltage support strength of the high-proportion new energy power system based on the real-time short-circuit ratio index and the real-time critical short-circuit ratio index; and distinguishing whether the high-proportion new energy power system is in a critical state. The application can effectively realize real-time monitoring of the voltage support strength of the high-proportion new energy power system, analyze the static voltage stability margin of the system, locate the weak point of the system and guarantee the safe and stable operation of the high-proportion new energy power system.

Claims

1. A method for real-time monitoring of the critical short-circuit ratio in a high-proportion renewable energy power system, characterized in that, The method includes: Obtain the operating parameters of the high-proportion renewable energy power system, and based on the operating parameters, determine the real-time short-circuit ratio index used to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system; Based on the aforementioned operating parameters, a real-time critical short-circuit ratio index is determined to identify the static stability limit of the voltage support strength of the high-proportion new energy power system. Based on the real-time short-circuit ratio index and the real-time critical short-circuit ratio index, a static stability margin index is obtained to determine the voltage support strength of the high-proportion new energy power system. Based on the static stability margin index and the preset margin quantification standard used to determine the voltage support strength of the high-proportion new energy power system, determine whether the high-proportion new energy power system is in a critical state; The determination of the real-time short-circuit ratio index, used to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system, based on the operating parameters, includes: Based on the aforementioned operating parameters, an equivalent analysis model for the high-proportion renewable energy power system is established, as follows: in, The Thevenin equivalent potential of the system, For new energy grid connection nodes Real-time operating voltage, The Thevenin equivalent impedance of the system, For nodes The equivalent current flowing into the system; Based on the equivalent analysis model, a real-time short-circuit ratio index is established to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system. The real-time short-circuit ratio index is as follows: in, The real-time short-circuit ratio is indicated by the subscript P, which is the unit number based on the nominal voltage. i Number the nodes. The Thevenin equivalent potential of the system, For new energy grid connection nodes Real-time operating voltage; The real-time critical short-circuit ratio index of the static stability limit of the voltage support strength of the high-proportion new energy power system is as follows: in, This is the real-time critical short-circuit ratio indicator. The Thevenin equivalent potential of the system The modulus, For new energy grid connection nodes Real-time operating voltage The amplitude; The static stability margin index of the voltage support strength of the high-proportion new energy power system is as follows: in, As a static stability margin indicator, The real-time short-circuit ratio is the key indicator. The real-time critical short-circuit ratio is the key indicator. The preset margin quantification standard is as follows: If the static stability margin index If the value is greater than 0, it is determined that the high-proportion new energy power system is in a stable state; If the static stability margin index If the value is 0, then the high-proportion new energy power system is determined to be in a static voltage critical stability state; If the static stability margin index If the value is less than 0, it indicates that the high-proportion new energy power system is in an unstable state.

2. A system for real-time monitoring of the critical short-circuit ratio in a high-proportion renewable energy power system, characterized in that, The system includes: The first indicator unit acquires the operating parameters of the high-proportion renewable energy power system and, based on the operating parameters, determines the real-time short-circuit ratio indicator used to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system. The second indicator unit determines, based on the operating parameters, the real-time critical short-circuit ratio indicator for judging the static stability limit of the voltage support strength of the high-proportion new energy power system. The margin unit, based on the real-time short-circuit ratio index and the real-time critical short-circuit ratio index, obtains a static stability margin index used to determine the voltage support strength of the high-proportion new energy power system. The discrimination unit determines whether the high-proportion new energy power system is in a critical state based on the static stability margin index and the preset margin quantification standard used to judge the voltage support strength of the high-proportion new energy power system. The determination of the real-time short-circuit ratio index, used to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system, based on the operating parameters, includes: Based on the aforementioned operating parameters, an equivalent analysis model for the high-proportion renewable energy power system is established, as follows: in, The Thevenin equivalent potential of the system, For new energy grid connection nodes Real-time operating voltage, The Thevenin equivalent impedance of the system, For nodes The equivalent current flowing into the system; Based on the equivalent analysis model, a real-time short-circuit ratio index is established to quantitatively evaluate the voltage support strength of the high-proportion renewable energy power system. The real-time short-circuit ratio index is as follows: in, The real-time short-circuit ratio is indicated by the subscript P, which is the unit number based on the nominal voltage. i Number the nodes. The Thevenin equivalent potential of the system, For new energy grid connection nodes Real-time operating voltage; The real-time critical short-circuit ratio index of the static stability limit of the voltage support strength of the high-proportion new energy power system is as follows: in, This is the real-time critical short-circuit ratio indicator. The Thevenin equivalent potential of the system The modulus, For new energy grid connection nodes Real-time operating voltage The amplitude; The static stability margin index of the voltage support strength of the high-proportion new energy power system is as follows: in, As a static stability margin indicator, The real-time short-circuit ratio is the key indicator. To identify indicators in real time; The preset margin quantification standard is as follows: If the static stability margin index If the value is greater than 0, it is determined that the high-proportion new energy power system is in a stable state; If the static stability margin index If the value is 0, then the high-proportion new energy power system is determined to be in a static voltage critical stability state; If the static stability margin index If the value is less than 0, it indicates that the high-proportion new energy power system is in an unstable state.

3. A computer device, characterized in that, include: One or more processors; A processor is used to execute one or more programs; When the one or more programs are executed by the one or more processors, the method of claim 1 is implemented.

4. A computer-readable storage medium, characterized in that, It contains a computer program, which, when executed, implements the method as described in claim 1.

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