A study on current stabilization technology of transmitter for controlled-source frequency electromagnetic sounding

A controlled-source frequency electromagnetic sounding system needs high-power low-frequency pulse current supplied by the transmitter. And the pulse current is required to possess high current stability. The article proposes a high precision mixed-signal (analog and digital) plan for current stabilization, and illustrates the principle and design method of the plan. A sampler of transmitter is developed with the current stabilization plan, for which many logging tests have been made in Daqing Oilfield, and the testing result demonstrates that the stability of output current of the transmitter has reached 0.3%.