The optimization of design parameters and methods for electrostatic voltage sensors based on rotational actuators is presented. The analytical software model used for this optimization process is discussed. Voltage excitation leads to an electrostatic attractive force, inducing a deflection of the actuator which in turn is detected using capacitance measurement. We look at devices with parallel plate capacitances in a rotational design, which allows direct, substitution and compensation measurements of RF voltages. An analytical and a numerical model for this type of sensor are presented, focusing on absolute and relative sensitivity and precision for metrology purposes. The main design parameters are extracted from this model and variation of each parameter is discussed. Using this model, sensor designs are developed which fulfill the requirements for electrostatic voltage sensing for different sensitivity and range requirements.