EV Charging System Without Power Factor Correction Circuit

Solution Overview

Problem

Conventional in-vehicle charging circuits for eco-friendly vehicles include power factor correction circuits, which increase the cost, volume, and weight of the vehicles, posing an economic burden on consumers.

Innovation Solution

A charging system without a power factor correction circuit, utilizing a rectifying circuit, a converter with high frequency switching circuits, and a transformer to improve the power factor and current quality of the grid current, while minimizing the use of capacitors and filters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a power factor correction circuit is included in the in-vehicle charging circuit, then the power factor and current quality are improved, but the cost, volume, and weight of the vehicle increase

Engineering Contradiction:

Improvepower factor and current qualityVSAvoidvehicle weight

Core Design Contradiction:

Object-affected harmful factorsVSWeight of stationary object

Solution Approach 1:

The patent extracts and removes the power factor correction circuit from the in-vehicle charging circuit, eliminating the components dedicated to power factor correction while maintaining acceptable power factor performance through the optimized converter design

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The converter is designed to perform multiple functions simultaneously: it converts voltage, controls power flow to the battery, and maintains power factor performance, eliminating the need for a separate power factor correction circuit

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Object-affected harmful factors

If a power factor correction circuit is included in the in-vehicle charging circuit, then the power factor and current quality are improved, but the cost of the vehicle increases

Engineering Contradiction:

Improvepower factor and current qualityVSAvoidvehicle cost

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent extracts and removes the power factor correction circuit from the in-vehicle charging circuit, eliminating the components dedicated to power factor correction while maintaining acceptable power factor performance through the optimized converter design

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent merges the power factor correction function into the main converter circuit, where the converter simultaneously performs voltage conversion and power factor management, reducing the total component count and manufacturing cost

Inventive Principle:

Principle #5Merging (Combining)

3Object-affected harmful factors

If a power factor correction circuit is included in the in-vehicle charging circuit, then the power factor and current quality are improved, but the volume of the vehicle increases

Engineering Contradiction:

Improvepower factor and current qualityVSAvoidvehicle volume

Core Design Contradiction:

Object-affected harmful factorsVSVolume of moving object

Solution Approach 1:

The patent extracts and removes the power factor correction circuit from the in-vehicle charging circuit, eliminating the components dedicated to power factor correction while maintaining acceptable power factor performance through the optimized converter design

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The converter is designed to perform multiple functions simultaneously: it converts voltage, controls power flow to the battery, and maintains power factor performance, eliminating the need for a separate power factor correction circuit

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 achieves improved performance and cost-effectiveness by eliminating the need for a power factor correction circuit, reducing the overall size, weight, and cost of the charging system, while maintaining the quality and power factor of the grid current.

Implementation Method 1

a transformer having a secondary-side coil to which the high frequency signal converted by the first high frequency switching circuit is input and a primary-side coil electromagnetically coupled to the secondary-side coil to generate and output the high frequency signal applied to the secondary-side coil

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS10498157B2Charging system without power factor correction circuit

Publication Date: 2019.12.03 HYUNDAI MOTOR CO LTD

AI summary

A charging system for improving a power factor and a current quality in a grid stage is provided. The charging system includes a rectifying circuit that is configured to rectify a grid power and a converter that is configured to receive a voltage-current rectified by the rectifying circuit and convert the voltage-current into a charge voltage-current to be provided to a battery. A capacitor is connected across a connection end of the rectifying circuit and the converter. The converter includes a first high frequency switching circuit, a transformer, and a second high frequency switching circuit.