Composite detection apparatus and method of pulsed eddy current and magnetic flux leakage in oil and gas pipeline

A composite detection apparatus of pulsed eddy current and magnetic flux leakage in an oil and gas pipeline, wherein the composite detection apparatus of pulsed eddy current and magnetic flux leakage in an oil and gas pipeline comprises a pulsed excitation probe, and the pulsed excitation probe comprises a magnet, a first yoke, a second yoke, an excitation coil, a first receiving coil, a second receiving coil, and a magnetic sensor;

• a first end of the first yoke away from an inner surface of the oil and gas pipeline is fixedly mounted on a first end of the magnet, a first end of the second yoke away from the inner surface of the oil and gas pipeline is fixedly mounted on a second end of the magnet, and the magnet, the first yoke, and the second yoke are configured to apply a static magnetic field to the inner surface of the oil and gas pipeline;
• the excitation coil is sleeved on the magnet, the excitation coil is configured to be applied with a pulsed voltage signal, when the pulsed voltage signal is at a high level, the excitation coil is configured to generate an electromagnetic field, and the electromagnetic field and the static magnetic field are in a same direction, so that the inner surface of the oil and gas pipeline is in a saturation magnetization state, and when the pulsed voltage signal is at a rising edge and a falling edge, the excitation coil is configured to generate a first eddy current field at a position of the inner surface of the oil and gas pipeline corresponding to the first yoke and a second eddy current field at a position corresponding to the second yoke;
• the first receiving coil is sleeved on a second end of the first yoke close to the inner surface of the oil and gas pipeline, and the second receiving coil is sleeved on a second end of the second yoke close to the inner surface of the oil and gas pipeline;
• and the first receiving coil is configured to receive an induced magnetic field generated by the first eddy current field and output a first voltage signal, and the second receiving coil is configured to receive an induced magnetic field generated by the second eddy current field and output a second voltage signal, thereby implementing eddy current detection;
• and
• the magnetic sensor is located between the first receiving coil and the second receiving coil, and the magnetic sensor is configured to receive an induced magnetic field generated by the inner surface of the oil and gas pipeline in the saturation magnetization state and output a voltage signal, thereby implementing magnetic flux leakage detection.