A bad data identification algorithm based on voltage code

With the increasing complexity of modern power systems, the quality and integrity of measurement data have become crucial for ensuring the system's normal operation. Research and application of bad data identification techniques in power systems are gaining more attention. This paper draws an analogy to base-n code in mathematics and computer science, proposing voltage code based on the impedance matrix of power network nodes. It analyzes the role of voltage code as a ‘weight’ reflecting the impact of current injection on voltage. An error phasor AU containing information about bad data is constructed by measuring current and voltage. The paper analyzes the different effects of various types and quantities of bad data on AU, revealing three distinct characteristics of AU. Based on these characteristics, an algorithm for identifying bad data using voltage code and the measurement data itself is proposed. This algorithm does not require redundant measurements and can quickly identify bad data during system operation. The effectiveness of this method is validated through simulations using the IEEE 39-node system as a typical case study.