Control system for hydraulically powered ac generator

Abstract

Systems and methods for use in controlling a hydraulically powered AC generator are provided. One control system includes a valve system. The valve system includes a fixed valve configured to provide a substantially constant flow rate of the fluid through the fixed valve to the hydraulically powered AC generator. The valve system further includes a variable valve configured to provide a variable flow rate of the fluid through the variable valve to the hydraulically powered AC generator. The control system further includes a sensor device configured to measure a speed of movement of a component of the hydraulically powered AC generator. The control system further includes a control circuit configured to control the variable flow rate of the variable valve based on the speed of movement of the component measured by the sensor device.

1 - 19 . (canceled) 
     
     
         20 . A control system for controlling an alternating current (AC) generator, the control system comprising:
 a sensor device configured to measure a speed of movement of a gear or shaft of the AC generator; and   a control circuit configured to generate a control signal based on the speed of movement of the AC generator measured by the sensor device, wherein the control circuit is further configured to transmit the control signal to a control device configured to control a hydraulic motor coupled to drive the AC generator.   
     
     
         21 . The control system of  claim 20 , wherein the hydraulic motor is controlled by a valve system. 
     
     
         22 . The control system of  claim 20 , wherein the sensor device comprises a Hall Effect sensor configured to measure a change in a magnetic field caused by the movement of the AC generator. 
     
     
         23 . The control system of  claim 20 , wherein the sensor device comprises an optical encoder sensor, the optical encoder sensor comprising a light source configured to generate light and a light detection device configured to detect changes in the light reflected off of the AC generator. 
     
     
         24 . The control system of  claim 20 , wherein the sensor device comprises a magnetic pickup sensor. 
     
     
         25 . The control system of  claim 20 , wherein the control circuit is configured to generate the control signal based on both the speed of movement of the AC generator measured by the sensor device and an AC output frequency of the AC generator measured using a second sensor device. 
     
     
         26 . The control system of  claim 20 , wherein the control circuit is configured to generate the control signal to maintain an AC output frequency of the AC generator within a threshold range of a target AC output frequency. 
     
     
         27 . A control system for controlling a hydraulically powered alternating current (AC) generator, the control system comprising:
 a sensor device configured to measure a speed of rotation of the hydraulically powered AC generator; and   a control circuit configured to control the speed of rotation of the hydraulically powered AC generator measured by the sensor device.   
     
     
         28 . The control system of  claim 27 , wherein the sensor device is configured to measure a speed of movement of a component of the hydraulically powered AC generator. 
     
     
         29 . The control system of  claim 28 , wherein the component is a gear or shaft of the hydraulically powered AC generator. 
     
     
         30 . The control system of  claim 27 , wherein the sensor device comprises at least one of a Hall Effect sensor, an optical encoder sensor, or a magnetic pickup sensor. 
     
     
         31 . The control system of  claim 27 , wherein the control circuit is configured to generate the control signal based on both the speed of rotation of the hydraulically powered AC generator as measured by the sensor device and an AC output frequency of the hydraulically powered AC generator measured using a second sensor device. 
     
     
         32 . The control system of  claim 27 , wherein the control circuit is configured to generate the control signal to maintain an AC output frequency of the hydraulically powered AC generator within a threshold range of a target AC output frequency. 
     
     
         33 . The control system of  claim 27 , wherein the control circuit further comprises:
 a hydraulic motor coupled to the hydraulically powered AC generator; and   a variable valve system coupled to the hydraulic motor, wherein the control circuit alters a variable flow rate of the variable valve system based on the speed of rotation of the hydraulically powered AC generator measured by the sensor device.   
     
     
         34 . The control system of  claim 33 , wherein the variable valve system comprises:
 a fixed valve configured to provide a substantially constant flow rate of the fluid through the fixed valve to the hydraulic motor coupled to the hydraulically powered AC generator; and   a variable valve configured to provide a variable flow rate of the fluid through the variable valve to the hydraulic motor coupled to the hydraulically powered AC generator.   
     
     
         35 . A method of controlling a hydraulically powered alternating current (AC) generator, comprising:
 measuring a speed of rotation of the hydraulically powered AC generator with a first sensor; and   controlling the speed of rotation of the hydraulically powered AC generator by controlling a variable flow of fluid to a hydraulic motor coupled to the hydraulically powered AC generator.   
     
     
         36 . The method of  claim 35 , wherein measuring the speed of rotation of the hydraulically powered AC generator with the first sensor further comprises measuring a speed of rotation of a component of the hydraulically powered AC generator. 
     
     
         37 . The method of  claim 35 , wherein the first sensor comprises at least one of a Hall Effect sensor, an optical encoder sensor, or a magnetic pickup sensor. 
     
     
         38 . The method of  claim 35 , wherein controlling the speed of rotation of the hydraulically powered AC generator further comprises controlling the speed of rotation of the hydraulically powered AC generator based on both the speed of rotation of the hydraulically powered AC generator and an AC output frequency of the hydraulically powered AC generator. 
     
     
         39 . The method of  claim 38 , further comprising maintaining the AC output frequency of the hydraulically powered AC generator within a threshold range of a target AC output frequency.