SIMO Power Converter Inductor Current Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Single-Inductor-Multiple-Output (SIMO) devices experience inter-channel oscillations in continuous conduction mode, leading to inconsistent energy delivery to multiple outputs, as inductor current from previous cycles influences subsequent cycles, resulting in undesired pulse energy.
Innovation Solution
A power converter with a controller that maintains a minimum inductor current between charging cycles and adjusts the charging inductor current based on the difference between output voltage signals and target voltage signals, using an integrator, squaring device, summer, and square root device to generate a root-mean-square charging current signal, ensuring consistent energy delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If SIMO device operates in continuous conduction mode with inductor current from previous cycles influencing subsequent cycles, then the device can maintain continuous current flow, but inter-channel oscillations occur leading to inconsistent energy delivery
Solution Approach 1:
The controller pre-charges the inductor to a predetermined minimum current level before each discharge cycle. This preliminary action ensures that the inductor starts each cycle with a known, consistent current baseline, preventing inter-channel oscillations and ensuring stable energy delivery to multiple outputs while maintaining continuous conduction mode operation.
2Adaptability or versatility
If inductor current is allowed to vary freely between cycles, then the device can adapt to load changes, but inter-channel oscillations result in undesired pulse energy
Solution Approach 1:
The controller monitors the inductor current and compares it against reference values, then adjusts the charging current accordingly. This feedback mechanism maintains the minimum current threshold while preventing excessive current buildup, thereby adapting to load changes without causing inter-channel oscillations and ensuring precise pulse energy delivery to each output channel.
3Device complexity
If multiple outputs are served from a single inductor, then device complexity is reduced, but inter-channel oscillations cause inconsistent energy distribution
Solution Approach 1:
The controller acts as an intermediary between the single inductor and multiple output channels. It manages the inductor's charging and discharging cycles, ensuring that each output receives consistent energy despite sharing a common inductor. This intermediary control prevents inter-channel oscillations while maintaining the simplified single-inductor architecture.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces inter-channel oscillations and ensures consistent energy delivery to multiple outputs by maintaining a minimum inductor current and adjusting charging current according to desired voltage levels, improving the stability and efficiency of SIMO devices.
Implementation Method 1
Power converters can include Single-Input-Multiple-Output (SIMO) devices that store current in a single inductor based on an input signal and selectively discharging the stored current to multiple loads
Data Source
AI summary
A power converter is disclosed. The power converter includes a Single-Input-Multiple-Output (SIMO) device includes a first transistor connected to an input and a first end of an inductor, a second transistor connected to a second end of the inductor and a first output, and a third transistor connected to the second end of the inductor and a second output. The power converter also includes a controller connected to the SIMO device and is configured to maintain a minimum inductor current through the inductor between charging cycles and to cause the minimum inductor current to transition to a charging inductor current during a charging cycle. The charging inductor current is based on a difference between an output voltage signal and a target voltage signal.