Active detection of partial bypass in smart meters via embedded load injection

Abstract Electricity theft is still a challenge for utility providers. The bypass is a common technique, among other methods employed. The partial bypassing, where a fraction of the current is diverted, is particularly more difficult to detect. This paper proposes a novel, approach for identifying partial bypass tampering in smart meters based on hardware-assisted. The proposed method uses a controlled resistive load within the meter, which introduces a known current increment into the sensing path. This embedded load is controlled by a TRIAC, enabling precise connection and disconnection. A detection coefficient is introduced, which is computed using the measured current before and after activation to indicate tampering. The advantage of this technique is its independence from external infrastructure, historical consumption data, or complex analytical models. Thus, the method can be used in real-time to verify the current sensing integrity. The proposed method adds minimal hardware, making it suitable for integration into existing smart meter firmware. The results were validated using LTSPICE and through the experimental implementation of a case study. The results show the effectiveness of the proposed solution in detecting partial bypass scenarios.