Devices, systems, and methods for balancing closely coupled rotating machinery

A system for balancing coupled rotating machinery, the system comprising:

• a first piece of rotating machinery rotating at a first speed;
• a second piece of rotating machinery rotating at a second speed, that is different than the first speed, such that together the first and second speeds result in a complex vibration;
• and
• a controller configured to determine an average vibration of the first piece of rotating machinery;
• wherein the controller is configured to interpolate the average vibration of the first piece of rotating machinery from the complex vibration in less than one beating period and by estimating at two or more points along a demodulated complex vibration;
• wherein the controller determines a balance correction command based on the interpolated average vibration;
• and
• the controller controls the first piece of rotating machinery or the second piece of rotating machinery based on the balance correction command.

A method of providing active vibration control within an aircraft, the method comprising:

• receiving vibration data from at least a first rotating machine and a second rotating machine;
• comparing the vibration data and determining a duration of a beat cycle;
• applying rules based upon the duration of the beat cycle, wherein the step of applying rules comprises;
• applying a first rule when the beating period or the beating cycle is less than about 0.5 seconds;
• applying a second rule when the beating period or the beating cycle is between about 0.5 seconds and about 3 seconds;
• applying a third rule when the beating period or the beating cycle is between about 3 seconds and about 10 seconds;
• applying a fourth rule when the beating period is longer than about 10 seconds;
• and
• sending a balance correction command to the first rotating machine or the second rotation machine
• determining a balance correction command based on the step of applying rules;
• and
• controlling the first rotating machine or the second rotating machine based on the correction command.

A method of providing active vibration control within an aircraft, the method comprising:

• receiving vibration data from at least a first rotating machine and a second rotating machine;
• determining a beating period from the vibration data;
• estimating properties of a demodulated complex vibration during the beating period;
• interpolating an average vibration of at least the first or second rotating machine, wherein interpolating the average vibration comprises estimating two or more points along the demodulated complex vibration;
• and
• sending a balance correction command to the first rotating machine or the second rotation machine;
• determining a balance correction command based on the interpolated average vibration;
• and
• controlling the first rotating machine or the second rotating machine based on the correction command.

A method of providing active vibration control within an aircraft, the method comprising:

• receiving vibration data from at least a first rotating machine and a second rotating machine;
• determining a beating period from the vibration data;
• estimating properties of a demodulated complex vibration during the beating period;
• interpolating an average vibration of at least the first or second rotating machine, wherein interpolating the average vibration comprises estimating an intersection of perpendicular bisectors of each of two or more points along the demodulated complex vibration;
• and
• sending a balance correction command to the first rotating machine or the second rotation machine
• determining a balance correction command based on the interpolated average vibration;
• controlling the first rotating machine or the second rotating machine based on the correction command.