Three-Terminal Power Line Parameter Estimation from Pre-Fault Data
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining network parameters of power lines terminated by three terminals, especially those connected to inverter-based resources, face challenges such as requiring multiple measurement sets, high computational burden, and susceptibility to poor initial guesses, particularly in scenarios with inverter-based resources and poor initial conditions.
Innovation Solution
A method that uses a single-step or two-step approach to estimate network parameters using pre-fault measurements from three terminals, eliminating the risk of poor initial guesses by determining input parameters for a network model based on differences in electrical parameters among sections, and providing these parameters to control and monitoring devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple measurement sets are used to estimate line parameters (as in second approach), then measurement precision is improved, but device complexity and storage requirements increase
Solution Approach 1:
The patent applies preliminary action by using pre-fault measurements (collected before the actual fault occurs) to estimate line parameters. This allows the system to prepare and calculate parameter estimates in advance, using normal operating conditions data, so that when a fault occurs, the estimation can be performed quickly without requiring multiple post-fault measurement sets, thereby reducing storage and computational burden during fault conditions.
2Speed
If analytical optimization techniques like Newton's method are used (as in third approach), then convergence speed is improved, but reliability deteriorates due to dependence on initial guess
Solution Approach 1:
The patent uses pre-fault measurements to establish initial conditions and measurement sets before the fault occurs. This preliminary data collection and processing provides a solid foundation for the parameter estimation algorithm, ensuring that when the actual estimation is performed, it starts with high-quality initial data that improves both convergence speed and reliability, eliminating the uncertainty of poor initial guesses during fault conditions.
3Measurement precision
If multiple pre-fault measurement sets are required (as in first approach for IBRs), then parameter estimation accuracy is improved, but productivity decreases due to additional measurement requirements
Solution Approach 1:
The patent requires only a single set of pre-fault measurements to be collected before the fault occurs. This single measurement set is sufficient for the parameter estimation algorithm to accurately determine line parameters. By using this preliminary single measurement set effectively through the proposed estimation method, the system achieves accurate parameter estimation without requiring multiple pre-fault measurement sets, thereby improving productivity and reducing measurement data collection requirements.
Data Source
Figure 1a
Figure 1b
Figure 2~3
AI summary
The present disclosure relates to a method for determining at least one network parameter of a network comprising a power line being terminated by at least three terminals. The method comprises: obtaining measurements of the at least three terminals, terminating the power line at respective ends of the power line, obtaining at least one input parameter for a network model of the network based on the obtained measurements of the at least three terminals, determining the at least one network parameter based on the at least one input parameter for the network model and the network model, and providing the at least one network parameter to a device being configured to control, monitor, and/or analyse the network. The present disclosure also relates to a respective device and system.