Adaptive flow control

A method comprising the steps of:

• (a) determining a duty cycle for a motor operatively connected to a fixed-displacement fluid pump by determining a defined on-time duration and a defined off-time duration of the motor for a defined cycle period that is equal to an aggregate of the defined on-time duration and the defined off-time duration;
• (b) driving the motor to operate according to the duty cycle;
• (c) sensing a parameter related to a rotational period of a component driven by the motor;
• (d) determining a measured drive speed of the motor based on the sensed parameter related to the rotational period of the component driven by the motor;
• (e) adjusting the duty cycle based on a difference between the measured drive speed of the motor and an expected drive speed of the motor;
• and
• (f) repeating steps (b) through (e).

A pump controller comprising:

• one or more processors;
• and
• computer-readable memory encoded with instructions that, when executed by the one or more processors, cause the pump controller to:
• (a) determine a duty cycle for a motor operatively connected to a fixed-displacement fluid pump by determining a defined on-time duration and a defined off-time duration of the motor for a defined cycle period that is equal to an aggregate of the defined on-time duration and the defined off-time duration;
• (b) drive the motor to operate according to the duty cycle;
• (c) receive, from a sensing device, an indication of a parameter related to a rotational period of a component driven by the motor;
• (d) determine a measured drive speed of the motor based on the sensed parameter related to the rotational period of the component driven by the motor;
• (e) adjust the duty cycle based on a difference between the measured drive speed of the motor and an expected drive speed of the motor;
• and
• (f) repeat steps (b) through (e).