Parallel Power Supply Current Equalization via Compensation

Solution Overview

Problem

Existing power supply systems with multiple modules connected in parallel face complexity and increased cost due to the need for multiple voltage and current loops to achieve current equalization, making it difficult to simplify the current equalization control method.

Innovation Solution

A power supply device with a master and slave power supply module configuration, where a control module generates current compensation signals based on the output currents and voltage to adjust the control signals, allowing for current equalization using a single voltage loop, thereby simplifying the control complexity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple voltage loops or current loops are used to realize current equalization between power modules, then current equalization is achieved, but device complexity and cost increase

Engineering Contradiction:

Improvecurrent equalizationVSAvoidcontrol loop complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the current equalization function from the traditional multi-loop control structure and implements it through a separate current detection and compensation mechanism. Current detectors measure output currents of each module, and a compensation circuit adjusts the control signal based on detected current differences, eliminating the need for multiple complex control loops while achieving current equalization

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces current detectors and a compensation circuit as intermediary components between the power modules and the control system. These intermediaries measure current outputs and provide compensation signals that adjust the control inputs, enabling current equalization without requiring multiple voltage or current loops in the main control path

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If multiple voltage loops or current loops are used to realize current equalization between power modules, then current equalization is achieved, but cost increases

Engineering Contradiction:

Improvecurrent equalizationVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent extracts the current equalization function from the traditional multi-loop control structure and implements it through a separate current detection and compensation mechanism. Current detectors measure output currents of each module, and a compensation circuit adjusts the control signal based on detected current differences, eliminating the need for multiple complex control loops while achieving current equalization

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs relatively simple and inexpensive current detectors and compensation circuits instead of complex multi-loop control systems. These components are easier to manufacture and integrate, reducing overall system cost while effectively achieving current equalization between parallel power modules

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS9608518B2Power supply device and control method thereof

Publication Date: 2017.03.28 DELTA ELECTRONICS INC(CN)

AI summary

A power supply device includes a master power supply module, a slave power supply module and a control module. The master power supply module is configured to output a master output current and an output voltage according to a master control signal. The slave power supply module is electrically connected in parallel to the master power supply module and configured to output a slave output current and the output voltage according to a slave control signal. The control module is electrically connected to the master power supply module and the slave power supply module and configured to output the master control signal according to the output voltage, generate a current compensation signal according to the master output current and the slave output current, and output the slave control signal according to the output voltage and the current compensation signal which is based on the master output current.