An improved rotary servovalve 
system employs a rotary magnetic solenoid having an armature that includes at least one permanent 
magnet. The armature is rotatable relative to a 
stator formed as an 
electromagnet which is energizable to create alternative electromagnetic fields having opposite polarities from each other. When deenergized, the 
stator allows the armature to return to a neutral, null position from positions of extreme rotation in opposite angular directions due to the magnetic force of the permanent 
magnet of the armature. The armature is coupled to carry a movable valve element in 
angular rotation therewith, so that flow through the servovalve of the 
system can occur in alternative directions. Also, the valve element is biased toward a position in which all of the valve ports are closed when power is removed from the rotary solenoid. The 
control circuit employed in the rotary servovalve 
system expands the bandwidth of response of the 
solenoid actuator by compensating for frequency variations in the input command 
signal and in the feedback 
signal. This compensation is achieved utilizing a combined proportional, integral, and 
differential amplification circuit. Also, imbalance of fluid forces within the servovalve mechanism can be avoided by utilizing a pair of inlet orifices, a pair of outlet orifices, a pair of first 
fluid control orifices, and a pair of second 
fluid control orifices. The orifices within each pair are located on opposite sides of the valve housing from each other.