Abstract: This paper focuses on the working principle of the single-phase fully controlled bridge rectifier circuit and its practical application in driving mutual induction coils in the field of transmission tower grounding resistance measurement, as well as the practical application of measuring clamp signal excitation technology.Firstly, this paper introduces the research background of the single-phase fully controlled bridge rectifier circuit, and deeply analyzes its significance in the fields of power electronics and heavy current control. Subsequently, it elaborates on the working principle of the circuit in detail, including its circuit structure, control strategy and performance characteristics. Through an in-depth analysis of the key components in the circuit, this paper illustrates how the single-phase fully controlled bridge rectifier circuit achieves stable DC voltage output via precise conduction control, thereby improving the efficiency and reliability of the system in the process of electric energy conversion. Finally, this paper applies the circuit to the development of a transmission tower grounding resistance measuring device. This technology is utilized to provide stable and controllable excitation signals for the mutual induction coils required in the measurement, so as to ensure the accurate operation of the measuring device in actual measurement scenarios.