Electronic control for a hydraulically driven generator

A method for operating a hydraulic control system comprising:

• sensing hydraulic fluid temperature in a fluid circuit;
• warming hydraulic fluid by circulating the fluid through portions of the fluid circuit bypassing a hydraulic motor, if sensed fluid temperature is below safe operating temperature;
• and supplying hydraulic fluid slowly through to the hydraulic motor once hydraulic fluid reaches safe operating temperature to gradually bring the motor up to desired speed so that full power operation can commence sensing hydraulic motor output characteristics;
• and apportioning fluid flow to the hydraulic motor in order to maintain constant motor output characteristics wherein apportioning comprises comparing sensed output characteristics with predetermined output characteristics, generating a control signal based on the comparison, and selectively controlling an electronically controlled hydraulic proportional valve to move incrementally within a valve chamber such that fluid is proportionally divided between a motor supply conduit in fluid communication with the hydraulic motor and a bypass conduit, which bypasses the hydraulic motor.

A method for operating a hydraulic system driven by an engine onboard a vehicle for supplying stable AC power despite fluctuations in engine speed, the method comprising:

• sensing fluid pressure in a fluid circuit;
• sensing fluid temperature in the fluid circuit;
• commencing operation of an auxiliary power source if sensed fluid pressure and temperature is sufficient;
• ceasing operation of an auxiliary power source if sensed fluid pressure or temperature is deficient by fully opening an electronically controlled hydraulic proportional valve to bypass all fluid flow to a hydraulic motor;
• warming hydraulic fluid by circulating the fluid through portions of the fluid circuit bypassing the hydraulic motor, if sensed fluid temperature is below safe operating temperature;
• supplying hydraulic fluid slowly to the hydraulic motor once hydraulic fluid reaches safe operating temperature to gradually bring the motor up to desired speed so that full power operation can commence;
• sensing hydraulic motor output characteristics;
• apportioning fluid flow to the hydraulic motor in order to maintain constant motor output characteristics;
• and
• preventing over-temperature damage to the hydraulic system when sensed fluid temperature exceeds safe operating temperature.