Fault Detection Circuit And System Design For High Voltage Electric Power Metering Systems

There are various artificial anomalies as well as system faults can occur in high voltage electric powermetering systems. Since usually targeted by advanced technical means, artificial anomalies are difficult todetect by traditional methods. Different detection methods should be adopted to detect these variousanomalies.Based on detailed analysis and calculation instance, a fault detection method is proposed in this paperto detect faults occurring on high voltage electric power metering systems, especially for short-circuit ofthe current transformer (CT)first circuit. The main contributions of this paper focus on detection circuitdesign and system design:1. Fault detection principle design diagram for high voltage electric power metering systems is proposedin this paper. For the issue that opening metering circuit in actual system is unavailable, a novelmeasuring method is presented by means of the added core through typed measurement transformer,which can achieve measurement without influence on normal operation of the metering circuit.2. Measurement signals are actively added in additional instrument transformers. The impedance changescould be obtained by measuring voltage changes of the measurement points. Vast experiments aretested to verify its validation.3. According to detection requirements,4groups8detection circuits, detection amplified power supplycircuit and PCB are designed, especially for CT port preamplifier, once partial excitation signalgenerator and detect circuit.4. High-performance embedded microprocessor STM32F103is used in the principle design for maincontrol computer. 5. In accordance with expected detection performance, fault distinguish criterion and quantitative settingare presented to carry out fundamental test.