To provide a digitally controlled current-to-pressure converter (CPC).
The digital CPC uses a digital controller and an onboard pressure transducer to accurately control the output pressure based on an input analog control signal. The digital controller includes an anti-silting algorithm that provides an impulse movement to a three-way rotary valve of the CPC to loosen and flush away silt contamination from the valve. A redundant seal stack including an intermediate passage to the hydraulic drain ensures a low pressure drop across the outboard seal to minimize the potential for leakage and to improve reliability of the CPC. The digital controller also includes redundancy and fault management algorithms that enable the use of multiple inputs and feedback signals for control of the CPC. Master/slave operation and transitioning is also provided by the digital controller.
Haruhiko Kato
Shigeo Shibata
Toshiyuki Kanai
Kayoko Miyoko