1. Title of Achievement:

Research and Design Method of Strongly Robust High-Dynamic Power Grid Parameter Identification Technology Based on Saddle Point Features

2. Proposed Achievement Type and Level:

Technology Invention, Development, and Promotion, Second Prize

3. Summary of the Achievement:

This project conducted a series of research efforts around power grid voltage parameter identification methods and high-precision electrical energy measurement technology. The key innovative outcomes are summarized as follows:

(1) Strongly Robust Power Grid Voltage Parameter Identification Method Based on a Nonlinear Observer

This method addresses various disturbances in the power grid by establishing a mathematical model of grid voltage that includes these disturbances. Based on this model and a nonlinear observer, an orthogonal signal generator was designed, along with optimized design of the loop filter and voltage-controlled oscillator structure. The resulting method can accurately identify power grid voltage parameters under disturbances, exhibiting strong robustness.

(2) Fast Dynamic Response Three-Phase Power Grid Voltage Parameter Identification Method

This method models the grid voltage as a dynamic system with an unknown grid frequency. An adaptive observer is designed to estimate the voltage parameters of this system. Even under unbalanced three-phase grid conditions, this method achieves steady-state error-free estimation with fast dynamic response, addressing the issues of poor accuracy and slow dynamic response in existing identification technologies during grid faults.

(3) High-Precision Electrical Energy Measurement Technology Under Fluctuating Load

To address the phase difference caused by current transformers, this project compensates for the angle of the digitized current signal after analog-to-digital conversion, reducing precision errors caused by lag during rapid load fluctuations. The power integration time window was shortened to one power frequency cycle, allowing positive and reverse electrical energy to be accumulated once per cycle. This method significantly reduces the probability of positive and reverse active power energy cancellation due to sudden current phase shifts within the time window, improving measurement accuracy under rapidly fluctuating load conditions.

4. Main Completing Units:

Xidian University

Yantai Dongfang WISDOM Electric Co., Ltd.