Power Converter Controller with Segmented Linear and Nonlinear Circuits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power converters face challenges in achieving fast response times to step changes in output voltage and current while maintaining tight output voltage regulation, particularly due to limitations in control loop bandwidth and susceptibility to noise, which affects stability and efficiency.
Innovation Solution
A controller for power converters that combines linear and nonlinear control circuits, where a digital nonlinear control circuit provides fast response for minimum-time transitions and a digital linear control circuit ensures accurate steady-state regulation, with feedback from output capacitor current to enhance control loop bandwidth and reduce noise sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional linear control circuit is used to maintain stability and reduce noise sensitivity, then output voltage regulation is improved, but response time to step changes deteriorates
Solution Approach 1:
The control circuit is segmented into two distinct parts: a linear control circuit for steady-state regulation and a nonlinear control circuit for transient response. This segmentation allows each part to specialize in its optimal function without compromising the other.
Solution Approach 2:
The system dynamically switches between linear and nonlinear control modes based on operating conditions. The nonlinear control circuit activates during transient states (startup, load changes, voltage scaling) and the linear control circuit takes over during steady-state operation.
2Speed
If the control loop bandwidth is increased to improve response time, then speed is improved, but susceptibility to noise increases
Solution Approach 1:
The control system dynamically adjusts its characteristics based on operating state. During transient conditions, the nonlinear controller provides fast response without being constrained by bandwidth limitations that would amplify noise during steady-state operation.
3Speed
If a nonlinear control circuit is used to achieve fast response times, then response time is improved, but stability and noise sensitivity worsen
Solution Approach 1:
The control circuit is segmented into two distinct parts: a linear control circuit for steady-state regulation and a nonlinear control circuit for transient response. This segmentation allows each part to specialize in its optimal function without compromising the other.
Solution Approach 2:
The system dynamically switches between linear and nonlinear control modes based on operating conditions. The nonlinear control circuit activates during transient states (startup, load changes, voltage scaling) and the linear control circuit takes over during steady-state operation.
4Speed
If switching frequency is increased to improve response time, then speed is improved, but power conversion efficiency deteriorates
Solution Approach 1:
The control system dynamically adapts its behavior based on operating conditions. The nonlinear controller enables fast response at moderate switching frequencies by optimizing the duty cycle trajectory, avoiding the need for continuously high switching frequencies that would increase losses.
Data Source
AI summary
A controller for use with a power converter including a switch configured to conduct to provide a regulated output characteristic at an output of the power converter, and method of operating the same. In one embodiment, the controller includes a linear control circuit, coupled to the output, configured to provide a first control signal for the switch as a function of the output characteristic. The controller also includes a nonlinear control circuit, coupled to the output, configured to provide a second control signal for the switch as a function of the output characteristic. The controller is configured to select one of the first and second control signals for the switch in response to a change in an operating condition of the power converter.