Inductive position sensors have been widely employed in nuclear reactors for monitoring the control rod position. Accurate control rod position information plays a crucial role in regulating the power of nuclear reactors. However, the inductive sensors currently used for control rod position detection exhibit limited measurement accuracy, which may adversely affect safety and reliability. In response to these issues, a segmented coil structure inductive position sensor based on the resonance principle is proposed in this paper. To improve the sensor sensitivity, a resonant circuit is implemented by connecting capacitors in series with the excitation and sensing coils, and a theoretical model is developed. Furthermore, optimizing the resonant capacitance can reduce the nonlinearity error of the sensor. To enhance the load-driving capability of the excitation source, a single-phase inverter circuit is proposed as the excitation source. Only one excitation signal is used to excite multiple coils. ANSYS simulations and experimental measurements are performed to compare sensors with and without the resonant circuit. The results validate the theoretical analysis and demonstrate that the sensor employing the resonant circuit significantly improves sensitivity and enhances linearity range. The sensor achieves a sensitivity of 0.1909 V/mm and a nonlinearity error of less than 2% over the full-scale span.