Modular DC/DC Converter for Dynamic EV Charging Voltage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current electric vehicle charging technologies face limitations in charging speed and power efficiency, particularly with conventional AC charging and existing DC charging systems, which restrict the ability to charge vehicles with varying voltage requirements and necessitate high-power transmission while ensuring safety through galvanic isolation.

Innovation Solution

A modular multiphase multilevel DC/DC converter (MMMDDC) system that dynamically adjusts voltage and current by reconfiguring modules in series or parallel, using passive or active rectifiers, and incorporating galvanic isolation to manage high voltage ranges and ensure efficient power delivery across a wide range of vehicles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If DC charging stations use fixed high voltage (e.g., 800V) to achieve high charging power, then charging speed is improved, but vehicles with lower voltage requirements cannot be charged efficiently and galvanic isolation becomes more complex

Engineering Contradiction:
Improvecharging speedVSAvoidcompatibility with different vehicle voltages
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The charging system is divided into multiple independent voltage levels (e.g., 400V, 800V, 1000V) that can be selectively activated. Each voltage level has its own power electronics modules that can be independently controlled, allowing the system to segment its output to match different vehicle requirements while maintaining high charging capability for 800V/1000V vehicles.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The charging station implements dynamic voltage switching capability where the output voltage can be changed in real-time based on the connected vehicle's requirements. The power electronics system can dynamically reconfigure its internal topology to provide different voltage levels, enabling adaptation from 400V to 1000V output without physical hardware changes.

Inventive Principle:
Principle #15Dynamics

2Reliability

If charging stations are operated independently with separate network connections to ensure safety, then galvanic isolation is maintained, but construction complexity increases and cost savings are minimal

Engineering Contradiction:
Improvesafety through galvanic isolationVSAvoidconstruction complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Multiple charging stations share a common high-voltage DC intermediate circuit and power pool, merging their electrical operations. The galvanic isolation is maintained through the inherent isolation properties of the DC-DC converter modules rather than through separate physical network connections, allowing electrical interconnection while preserving safety.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The common DC intermediate circuit acts as an intermediary that enables power sharing between charging stations. The system uses controlled power flow management and digital communication to coordinate charging operations across multiple stations, with the intermediate circuit serving as the mediating electrical interface that maintains isolation while enabling collaboration.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Adaptability or versatility

If power electronics cover a very high voltage range to accommodate vehicle battery voltage adjustments, then versatility is improved, but charging power drops due to component limits

Engineering Contradiction:
Improvevoltage range coverageVSAvoidcharging power
Core Design Contradiction:
Adaptability or versatilityVSPower

Solution Approach 1:

The power electronics system is segmented into multiple voltage-level modules (e.g., 400V modules, 800V modules, 1000V modules) that can be selectively activated. Each module is optimized for its specific voltage range, allowing the system to maintain high power output at each voltage level rather than attempting to cover the entire range with a single module design.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The charging station implements a universal power pool that can serve multiple voltage requirements simultaneously. The system can dynamically allocate power from different voltage-level modules to match the connected vehicle's needs, making the same infrastructure universally compatible with 400V, 800V, and 1000V vehicles while maintaining peak power capability for each.

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Reliability

If individual charging stations are used to ensure safety and independence, then reliability is maintained, but cost efficiency decreases compared to modular shared systems

Engineering Contradiction:
Improveoperational reliabilityVSAvoidcost efficiency
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The system merges multiple charging stations into a coordinated network that shares common infrastructure including the high-voltage DC intermediate circuit, power pool, and control systems. This consolidation reduces redundant components and infrastructure costs while maintaining operational independence through digital coordination and galvanic isolation.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The charging network implements dynamic resource allocation where power capacity can be dynamically assigned to different charging points based on real-time demand. The system can dynamically switch between operating modes (independent operation vs. coordinated power sharing) to optimize both reliability and cost efficiency depending on operational conditions.

Inventive Principle:
Principle #15Dynamics

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 system enables maximum power charging for electric vehicles, even at low voltage, while maintaining galvanic isolation, improving power quality, reducing component costs, and ensuring reliable operation by allowing flexible module configuration and redundancy, thus enhancing charging efficiency and safety.

Implementation Method 1

Each module has a DC/DC converter electrically connected to the common pair of output terminals in such a way that the DC/DC converter can take on energy from the common DC intermediate circuit and deliver it to at least one pair of output terminals

Methodology Applied
Scientific EffectElectrical energy conversion:

Data Source

PatentEP3333005B1Modular power electronics unit for charging an electrically powered vehicle
Publication Date: 2021.03.17 DR ING H C F PORSCHE AG
  • EP3333005B1 patent drawingFigure 1
  • EP3333005B1 patent drawingFigure 2A~2B
  • EP3333005B1 patent drawingFigure 3~4a

AI summary

The present invention relates to power electronics for charging at least one electrically powered vehicle, wherein the power electronics comprise at least two modules, each with at least one terminal pair with DC output, at least one rectifier (420), at least one AC input, at least one DC link and a number of switching elements (422, 423), wherein the switching elements (422, 423) are arranged at and/or between the DC outputs of the at least two modules such that at least one series and one parallel circuit configuration can be dynamically selected between the at least two modules by means of suitable switching states of the switching elements (422, 423).