Multi-phase Voltage Converter Ripple Suppression via Staggered Control Period Updates

Solution Overview

Problem

Multi-phase voltage converting devices experience significant output voltage ripple due to inconsistencies in carrier switching periods across phases, leading to inefficiencies and increased switching losses.

Innovation Solution

A multi-phase voltage converting device with multiple voltage converters connected in parallel, where each converter operates based on a control period selected from predetermined periods, and a control device updates these periods in a common update period, ensuring a time difference of 1/n of the update period across all converters, thereby maintaining phase differences and reducing ripple.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the control period is changed dynamically based on power requirements, then switching losses are reduced, but phase synchronization is disrupted causing increased output voltage ripple

Engineering Contradiction:

Improveswitching lossVSAvoidoutput voltage ripple

Core Design Contradiction:

Loss of energyVSObject-generated harmful factors

Solution Approach 1:

The control device determines the control period in advance based on power requirements and communicates it to all voltage converters before they execute the switching operation. This preliminary determination ensures that all phases can synchronize their control period changes while maintaining phase difference relationships, thereby reducing switching losses without causing output voltage ripple.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

A central control device acts as an intermediary between the power requirements and the voltage converters. It receives power requirement information, determines the appropriate control period, and distributes synchronized control period instructions to all voltage converters. This intermediary coordination ensures that dynamic control period adjustment does not disrupt phase synchronization.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Loss of energy

If different control periods are applied to different phases, then switching losses are optimized for each phase, but phase difference consistency is lost

Engineering Contradiction:

Improveswitching lossVSAvoidphase difference consistency

Core Design Contradiction:

Loss of energyVSStability of the object's composition

Solution Approach 1:

The control device determines the control period in advance based on power requirements and communicates it to all voltage converters before they execute the switching operation. This preliminary determination ensures that all phases can synchronize their control period changes while maintaining phase difference relationships, thereby reducing switching losses without causing output voltage ripple.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

All voltage converters share a common control period determined by the central control device based on overall power requirements. This merging of control period determination ensures that while each phase maintains its individual phase difference, the control period consistency across phases prevents output voltage ripple and optimizes switching losses system-wide.

Inventive Principle:

Principle #5Merging (Combining)

3Loss of energy

If the control period is updated simultaneously for all phases, then switching loss reduction is achieved, but phase synchronization errors occur

Engineering Contradiction:

Improveswitching lossVSAvoidphase synchronization precision

Core Design Contradiction:

Loss of energyVSManufacturing precision

Solution Approach 1:

The control device determines the control period in advance based on power requirements and communicates it to all voltage converters before they execute the switching operation. This preliminary determination ensures that all phases can synchronize their control period changes while maintaining phase difference relationships, thereby reducing switching losses without causing output voltage ripple.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS8050065B2Multi-phase voltage converting device, vehicle and control method of multi-phase voltage converting device

Publication Date: 2011.11.01 TOYOTA JIDOSHA KK

AI summary

A multi-phase voltage converting device includes voltage converters each performing voltage conversion based on a control period selected from among a plurality of predetermined control periods, and a control device indicating the control period to the voltage converters. The control device updates the control period of voltage converters in a predetermined period related commonly to the plurality of control periods. The update period is a least common multiple of the plurality of control periods. The plurality of voltage converters are n in number, and the control device successively updates the control periods for the plurality of voltage converters with a time difference equal to 1/n of the update period. Thereby, the multi-phase voltage converting device suppressing output voltage ripples can be provided.