2.2kw 220v 2 phase to 220v 3 phase VFD motor driver

A 2.2kW 220V 2-phase to 220V 3-phase Variable Frequency Drive (VFD) motor driver is a crucial component in industrial and commercial applications where precise control of motor speed and power efficiency are essential. 

This project is requested by an IOT company in Shenzhen, China, who wants a solution for their latest washing machine. The washing machine is designed to be used in the commercial field. It has much greater power than the typical family washing machine.

The VFD is designed to drive the motor. My workspace collaborated with 3 companies and over 10 engineers, designing, debugging, testing, and prototyping this product.

Virtualenv创建虚拟环境

安装:

pip install virtualenv

移动到指定文件夹目录,执行:

virtualenv {虚拟环境名}

在linux下激活虚拟环境,执行:

source {文件目录}/{虚拟环境名}/bin/activate

在windows的powershell里激活虚拟环境,执行:

.\{文件目录}\{虚拟环境名}\Scripts\activate

激活后提示符会发生变化

在linux和windows中都可以使用此命令退出虚拟环境

deactivate

fh5汽车调教笔记

胎压:

低胎压,增加抓地力(接触地面面积),太低容易过热;高胎压,减小抓地力(接触地面面积),转向零密度增高,太高容易失去抓地力。

胎压前低后高,偏转向过度(推尾);胎压前高后低,偏转向不足(推头)。

依据车重设置胎压,

<1000kg(2200lbs),设置1.5/1.5bar(21.75/21.75psi)

<1400kg(3100lbs),,设置1.8/1.8bar(26.1/26.1psi)

>1400kg(3100lbs),,设置2.0/2.0bar(29/29psi)

拉力、越野在此基础上 -0.3bar(-4.35psi),

直线加速,漂移:前胎最高后台最低,如3.8/1.0bar(55.11/14.5psi)。漂移车按习惯调整后胎胎压。

齿轮比:

看性能曲线图,看峰值扭矩和峰值马力的转速区间,这个区间是功率带power band,理想转速比如 5000rpm – 9300rpm。调整齿轮比,从第二档开始,每一档的转速起始和结束都在理想转速区间内。调整最终传动比,让车辆在马力峰值时达到最大极速。理论极速没有考虑空气下压力和只用了理想最终传动比计算得出的。起步地板油打滑,把第一档拉到偏向车速,齿轮比图上拉长。

万能齿轮比:

六速:2.89/1.99/1.49/1.18/0.97/0.81

七速:3.75/2.38/1.7/1.34/1.11/0.96/0.85

八速:3.88/2.68/2.01/1.6/1.33/1.14/1.00/0.89

轮胎定位:

外倾角:为了在弯道中外侧轮胎与地面接触面积最大化,提升抓地力

束角:外束角轻微改善转向不足,太大会让车变得不稳定,内束角让车保持直线。对于四驱和前驱这类天生转向不足的车,前轮可以加不超过0.5的外束角,后轮加不超过0.2的外束角。大马力后驱后轮加一点内束角,增加后轮稳定性。

前后倾角:初始直接最高,如果转向太灵活,再来调小。前后倾角越小,前轮就需要更多负外倾。

公路–外倾角:前-0.5,后-0.5;束角:前0.3,后0.1,前后倾角7.0

拉力/越野–外倾角:前0.0,后0.5;束角:前0.0,后0.0,前后倾角7.0

漂移–外倾角:前-5.0,后-2.0;束角:前5.0,后1.0,前后倾角7.0

直线加速–外倾角:前0.0,后0.0;束角:前0.0,后0.0,前后倾角7.0

试车反馈:

过弯时观察外侧轮胎的外倾角,理论0度是最理想,因为路面不平,过弯时有-2的外倾角都是合理的。注意不要出现正外倾。

轮胎温度,比赛中轮胎内侧温度依次高于中间和外侧温度。如果内测与外侧温差太大,超过10摄氏度,说明负外倾角过大,需要调小。

防倾杆:

前防倾杆软,后防倾杆硬,改善转向不足。弯中推尾(转向过度)调硬前防倾杆。

前驱或四驱:前1后65,提升弯中稳定性可以前10后55。后驱 前10后56

拉力/越野:前10后25, 直线加速:前65后1

弹簧:

与防倾杆相似,弹簧越软,重心转移越快。越硬,操控响应越好。太硬会失去抓地力。

前弹簧,软-转向过度,硬-转向不足

后弹簧,软-转向不足,硬-转向过度

前驱/四驱:前弹簧最软,后弹簧在2/3的位置,甚至有四驱调教是前面最软后面最硬。

后驱:前后不超过1/3,初始前弹簧可以设为80,后弹簧可以设为100,根据实际情况调整。

大马力后驱可以前后弹簧一样,设置一样最软。拉力和越野需要偏软,通常前弹簧不超过1/6,后弹簧不超过1/4,拉力常使用前软后硬提高转向,越野前后软硬通常一样。直线加速前弹簧最硬,后弹簧最软。

车身高度公路一般默认配平即可。拉力和越野前后车高都设为最高。直线加速前轮最高,后轮最低。漂移统一最低车高。

试车反馈:

悬挂系统:弹簧在静止时压缩程度在50%,如果不是很颠簸的路况下,弹簧压缩已经满了,那说明车子托底,这种情况可以调硬弹簧,调高压缩硬度,或者调高车身高度解决。一般弹簧压缩程度在5%~85%。平整路面弹簧压缩波动很大,需要把弹簧调硬,波动小,则需要调软。

阻尼:

回弹硬度:弹簧压缩之后复原的速度。压缩硬度:弹簧压缩的速度。

回弹硬度永远大于压缩硬度。理论上:压缩=回弹*(0.5 ~ 0.75)

fh5喜好较软的压缩,所以这个比值太硬了。回弹硬度在8~14之间,拉力和越野比值一般在0.25,公路一般在0.4 。 初始使用默认回弹硬度。

回弹硬度前软后硬的设置可以改善转向不足,前硬后软的设置可以改善转向过度。

前驱或四驱:一般前软后硬;直线加速:前最高后最低。

空气动力:

前下压力直接最高,后下压力越大,后轮抓地力越强,但是太大会造成转向不足。

后驱车甚至要把后下压力拉满。前驱和四驱一般前下压力最大,后下压力不超过一半。

直线加速不需要空气动力套件。

刹车:

刹车重心靠前,增加刹车时的转向过度,刹车重心靠后,增加刹车时的转向不足。通常刹车重心偏靠前。如果车本来转向就灵活,那刹车需要更多稳定性,那刹车重心就得偏后。

制动力看开不开ABS,不开ABS最好开小点或者不变,防止轮胎抱死。

差速器:

四驱有前差后差中央差速器三个板块。前驱只有前插,后去只有后叉。

0%代表差速器完全放开,两边轮子各转各的;100%代表差速器完全锁死,两个轮子转速时钟相同。前后差速器加速设置踩油门时差速器锁死的快慢,反之减速是松油门时锁死的快慢。中央差速器控制扭矩的前后分配,让车辆偏前驱或者偏后驱。

现实弯道中,我们需要内侧轮子转速小于外侧轮子,这样转向更灵活。

公路调教,前差加速20%~90%,马力大的来说偏高的前差加速会让弯中和出完更稳定。

拉力调教,前差加速30%~90%

越野调教,前差加速80%~100%

前差减速一般为0%,如果后差减速已经调高的情况下,依旧推尾(转向过度),那就要适当把前差减速调高

中央差速器:公路一般75%,拉力一般60%

前驱一般前差加速50%,减速0%,后驱一般后差加速80%,减速0%,如果是大马力后驱,适当调低后差加速,调高后差减速以增加稳定性。

后驱漂移,后差加速锁死速度100%,减速90%,锁的越死,车容易飘,把差速器焊死是一个原理。

ADS project: multifunctional PTZ, Automatic Defense System

This is a project created as my start-up, and it is a finished project on IndieGoGo and BiliBili. The products were delivered 2023/08.

ADS | Indiegogo

ADS多功能云台,现已开始众筹_哔哩哔哩_bilibili

In this project, my works are: developing a controller board for the system, the CAD design for chassis and the mass production management.

For the electrical part, the ADS needs a camera, IR thermal camera inputs, servo, and motor driver. The board requires a web server to control the system and access the cameras’ view. We used dual webserver protocol (websocket, http) to achieve the goal.

For CAD part, I used Solidworks to design a beautiful chassis for ADS. here’s some photos. 

Mass production management was actually the most difficult part of this project. Although the amount of our products is still small, we still have to collaborate with many people and different companies. Considered assembling, packaging, and the product failure rate.

However, regarding all the hard work from the good partners and us, we successfully delivered our products at the end.

Senior design: ReRam with Micron – Dynamics electron tunneling

This research is my senior design project. The project is sponsored by Micron.

Research resistive RAM (ReRAM) memory cell arrays, focusing on unexpected behavior induced between neighboring cells in a crossbar architecture. Start by using previously designed infrastructure to heat a cell, while measuring the electrical characteristics of its neighboring cells. Then, analyze the results, investigating the cell array limitations. Finally, refine the measuring infrastructure, research goals, and analysis method. The resulting cell limitation analysis will provide a broader ReRAM understanding to progress the memory chip industry.

Research: Child robot theater simulator

This is an ongoing research project, for the CodeS lab located at Virginia Tech (Nov 2022)

The robot shown now is a testing model. I’m working on a bigger 3D model of NAO robot now. The new 3D model has 20 separate parts and they are movable。

It’s a 3d robot viewer and simulator created by PyQT5. Continue developing different parts’ positions, bonding relationships, and angle movement.

This software is developed for CodeS lab for Undergraduate research: Child robot theater. The research is to deliver an intuitive simulator of the robot on a computer to younger kids, giving children a sense of programing on the robot. education-related.