Introduction to the latest wireless charging technology for electric vehicles at ORNL laboratory in the United States

alan000345

Introduction to the latest wireless charging technology for electric vehicles at ORNL laboratory in the United States [Copy link]

The Oak Ridge National Laboratory in Tennessee, USA, demonstrated the world's first 20-kilowatt wireless charging system for electric vehicles. Therefore, every time ORNL announces their research results, it attracts a lot of attention. When I was in charge of the electric vehicle wireless charging project last year, I used the design concept announced by ORNL as a reference to make our products as perfect as possible. Not long ago, ORNL announced another ORNL design titled "Bi-directional Wireless Power Flow for Medium-Duty Vehicle-to-Grid Connectivity", and ORNL designs are generally difficult to find. So, here I would like to share with you their newly announced product design. In order to convey the accuracy, I will directly quote their original text. Technical Accomplishments – Budget Period ISystem Level Diagram with Symmetric Double Sided LCC Resonant Tuning

System architecture determined and designed for all power conversion stages  Grid interface power converter with active rectification and power factor correction (rectifier/inverter)  High-frequency inverter / rectifier  Resonant tuning configuration (LCC) for primary and secondary  Electromagnetic coupling coils  Vehicle side rectifier / inverter  Overall control system Designed the control system for each power conversion stages for different scenarios  Vehicle battery power can be regulated from primary or secondary side  Grid power can be regulated from grid side That’s all for today. For this “Bi-directional Wireless Power Flow for Medium-Duty Vehicle-to-Grid Connectivity”, there are some more designs and tools used to test and develop the effects, as well as analysis of the final test results. I will continue sharing them tomorrow. This content is originally created by alan000345, a user of EEWORLD forum. If you want to reprint or use it for commercial purposes, you need to obtain the author's consent and indicate the source

alan000345

Let's take a closer look at the features of the new design today. Let's first look at the design of the three-phase power input:

The design of three-phase power input to IGBT is not of much reference value. The following coil design and compensation circuit can serve as a good reference.

Both the primary coil and the secondary coil here use double copper coils.

Let’s take another look at the design of the resonant tuning circuit topology,

Let’s take another look at the introduction of this design

Completed the design, modeling, and analysis of the double-sided LCC resonant tuning configuration that will be used in the resonant stage of the power architecture.  Derived linear models for double-sided LCC tuned architecture based on – Replacing WPT coils by loosely coupled model of the transformer – Approximating the output of the inverter by the fundamental frequency component  Analyzed sensitivity of the system to – Misalignment of coils along the x and y axis – Variation of coil-to-coil distance – Variation of load power

From the two pictures above, we can also find that an active rectifier is introduced on the secondary coil side to control the charging of the electric vehicle battery. This design can realize CC and CV charging.

I will write so much for today. Tomorrow I will continue to look at the test results of their new design and the useful simulation software.

alan000345

Let's take a look at the execution sensitivity analysis of the electric vehicle wireless charging device 1. Inverter current has near zero phase angle independent of load resistance 2. Inverter current has near zero phase angle independent of the coupling between the WPT coils 3. Primary coil current is constant independent of load resistance 4. Primary coil current is constant independent of coupling between the coils 1 and 2 Leads to high efficiency operation and the inverter does not need to be oversized 3 and 4 Primary side is decoupled from the secondary side disturbances

Complete the phase-locked loop design and performance analysis PLL provides the synchronization with the grid phase angle Phase-angle detection is extremely important for fast and accurate reactive power supply, voltage regulation, and other grid services Phase angle is immediately detected here (blue and red line overlap)

Complete the entire system model and obtain simulation resultsSimulations performed using MATLAB Simulink/SimPowerSystems, SABER, and PCIM Magnetic simulations use COMSOL and JMAG

Complete the entire system model simulation resultsGrid interface converter operation Ability to transition the power flow direction (t=0.25, command sent) Can operate in reactive power injection / absorption modes (capacitive or inductive reactive)

High-frequency inverter / rectifier and resonant stage simulations Vehicle charging mode (a) and vehicle discharging mode of operations Minimal current ripple on battery and primary side DC link Zero voltage and zero current switching by the converters for reduced switching losses

[attach]361507[/attach ]

Loss analysis and fault models of the entire system created to evaluate system efficiency performance to confirm the design

Well, we have introduced to you the specific design concept of the electric vehicle wireless charging equipment of Oak Ridge National Laboratory, the relevant software tools used in the test, and the final test results. I hope that it will be of some help to domestic friends who are doing research in this direction. I also hope that everyone can discuss and exchange ideas on the latest issues related to the design of this charging system.

大力水手阿萨德

Hi, could you send me a copy of this information?

alan000345

Popeye Assad published on 2018-10-19 15:29 Hello, can you send me a copy of this information?

You can take a look at this attachment Vehicle Technologies Office Merit Review 2018 Bi-Directional Wireless Power Flow.pdf (1.49 MB, downloads: 44)

2018-10-22 11:02 上传

点击文件名下载附件

. The wireless charging project we did last year was actually mainly based on the half-bridge welding machine in China. In theory, they are almost the same. The PFC regulations in China are a bit strict. When we did it, we didn’t make a PFC module. For specific PFC, you can refer to TI’s design. Foreign wireless charging is mainly developed based on TI’s chip.

ohlala44

alan000345 posted on 2018-10-22 11:04 You can take a look at this attachment. The wireless charging project we did last year was actually mainly based on the half-bridge welding machine in China. In theory, they are actually different...

Have you ever simulated it?