Control system using nonlinear delta-sigma modulator with switching period error compensation

A signal processing system, comprising:

• a nonlinear delta-sigma modulator that compensates for an error in a plant response signal by adjusting a duration of an on-time interval of a plant switching period to cause an average value of the plant response signal to converge toward a target signal value;
• wherein the plant response signal is output current;
• and
• wherein the nonlinear delta-sigma modulator adjusts an on-time of a plant switch in the plant switching period to compensate for a difference in the average value of the output current from the target signal value in a prior plant switching period.

A signal processing system, comprising:

• a nonlinear delta-sigma modulator that compensates for an error in a plant response signal by adjusting a duration of an on-time interval of a plant switching period to cause an average value of the plant response signal to converge toward a target signal value, wherein the nonlinear delta-sigma modulator includes:
• a loop filter having an input;
• a quantizer coupled to the loop filter, the quantizer having an output;
• and
• a feedback path coupled between the output of the quantizer and the input of the loop filter, wherein the feedback path determines an error for a plant switching period, wherein the feedback path further includes a combiner that calculates an accumulated error for multiple plant switching periods.

A signal processing system, comprising:

• a nonlinear delta-sigma modulator that compensates for an error in a plant response signal by adjusting a duration of an on-time interval of a plant switching period to cause an average value of the plant response signal to converge toward a target signal value, wherein the nonlinear delta-sigma modulator includes:
• a loop filter having an input;
• a quantizer coupled to the loop filter, the quantizer having an output;
• and
• a feedback path coupled between the output of the quantizer and the input of the loop filter, wherein the feedback path determines an error for a plant switching period;
• wherein:
• the nonlinear delta-sigma modulator includes a combiner coupled to the input of the loop filter that combines a modulator input with a signal from the feedback path;
• and
• the feedback path determines the error based in part on the modulator input.

A control system to provide a control signal to a nonlinear plant that generates a response signal responsive to the control signal, the control system comprising:

• valley switching logic to change a state of a plant switch when the plant quantity is minimized;
• compensation logic including a nonlinear delta-sigma modulator that compensates for an error in a plant response signal by adjusting a duration of an on-time of a plant switch to cause an average value of the plant response signal to converge toward a target signal value;
• and
• a pulse-width modulator, coupled to the valley switching logic and the compensation logic, to generate a control signal that controls the plant switch.

A method of processing signals utilizing a nonlinear delta-sigma modulator, the method comprising:

• in a nonlinear delta-sigma modulator, receiving a signal related via a nonlinear function to a time interval in a first plant switching period;
• in a forward path of the nonlinear delta-sigma modulator, determining the time interval in the first plant switching period by application of a nonlinear loop filter;
• and
• in a feedback path of the nonlinear delta-sigma modulator, compensating for an error in a plant response signal by adjusting a duration of the time interval in a subsequent second plant switching period to cause an average value of the plant response signal to converge toward a target signal value.