Variable positive displacement pump actuator systems

A pump system, comprising:

• a variable positive displacement pump having a lever arm configured to control a displacement of the variable positive displacement pump;
• and
• a variable positive displacement pump actuator system operatively connected to the lever arm of the variable positive displacement pump, comprising:
• a supply line configured to provide a supply pressure;
• a main pump line configured to provide a pump pressure greater than the supply pressure from the variable positive displacement pump;
• at least one electro-hydraulic servo valve (EHSV) in fluid communication with the supply line and the main pump line to receive the supply pressure and the pump pressure, the at least one electro-hydraulic servo valve configured to output a first regulated pressure and a second regulated pressure;
• a first control line in fluid communication with at least one of the at least one EHSV to receive the first controlled pressure;
• a second control line in fluid communication with at least one of the at least one EHSV to receive the second controlled pressure, wherein the at least one EHSV is a single EHSV in fluid communication with both the first control line and the second control line;
• a first hydraulic actuator configured to connect to and/or otherwise actuate a lever arm of the variable positive displacement pump, the first hydraulic actuator in fluid communication with the first control line and the supply line to receive the first control pressure and the supply pressure to control a position of the first hydraulic actuator, wherein the first hydraulic actuator includes a first piston connected to the lever arm, wherein the first control line is in fluid communication with a first side of the first piston, and the supply line is in fluid communication with a second side of the first piston such that a differential pressure between the first control line and the supply line causes motion of the first piston;
• and
• a second hydraulic actuator configured to connect to and/or otherwise actuate the lever arm of the variable positive displacement pump, the second hydraulic actuator in fluid communication with the second control line and the supply line to receive the second control pressure and the supply pressure to control a position of the second hydraulic actuator.

A variable positive displacement pump actuator system for a variable positive displacement pump, comprising:

• a supply line configured to provide a supply pressure;
• a main pump line configured to provide a pump pressure greater than the supply pressure from the variable positive displacement pump;
• at least one control valve in fluid communication with the supply line and the main pump line to receive the supply pressure and the pump pressure, the at least one control valve configured to output a first regulated pressure and a second regulated pressure;
• a first control line in fluid communication with at least one of the at least one control valve to receive the first controlled pressure;
• a second control line in fluid communication with at least one of the at least one control valve to receive the second controlled pressure;
• a first hydraulic actuator configured to connect to and/or otherwise actuate a lever arm of the variable positive displacement pump, the first hydraulic actuator in fluid communication with the first control line and the supply line to receive the first control pressure and the supply pressure to control a position of the first hydraulic actuator, wherein the first hydraulic actuator includes a first piston configured to connect to the lever arm, wherein the first control line is in fluid communication with a first side of the first piston, and the supply line is in fluid communication with a second side of the first piston such that a differential pressure between the first control line and the supply line causes motion of the first piston;
• and
• a second hydraulic actuator configured to connect to and/or otherwise actuate the lever arm of the variable positive displacement pump, the second hydraulic actuator in fluid communication with the second control line and the supply line to receive the second control pressure and the supply pressure to control a position of the second hydraulic actuator.