Open Source 6Kw Charger. Who Whats What Features?

[adamj12b]

WOW, I totally forgot about this thread.

I actually ordered the first prototype control board for the charger monday night. It should be here in a few weeks.

Some of the preliminary features will be:
Modular design: The control board uses a remote current sense and voltage sense board that allows for high resolution measurement using an energy metering IC. You can daisy chain up to 3 of these boards to the main controller to measure all the sources inside the controller. These would be AC input voltage and current, Power Factor Corrected DC voltage and current, and the only board that is required is DC output to batteries voltage and current. These boards can measure up to 400VDc or 264VAC RMS

Modular Driver: The driver outout section is designed to be customized to your needs. You can use a board that will output an analog referance voltage, you can use a MOSFET driver or you can use the HIGH popwer VLA500-01 IGBT driver, which can also drive mosfets.

Graphic Interface The main display of the unit is a decent size graphic LCD panel. It is backlit for easy viewing. This is where you can select what you want to use for charge profile.

Simple Interface: There is only 1 user interface to the charger. This is a rotary knob next to the LCD that you twist to move the selected item on the screen. You then push to select or set that item.

BMS Input: There is an input where you can connect a simple BMS signal that can be either 5 or 12 volts. (Jumper Selectable) This can be used for stop charging when a high cell condition occures, or could transfer the charger into the next stage of charge (Top Off)

Vehicle Interlock: There is an NO/NC relay included that will brovide charger interlock feature. You will be able to wire ignation or contactor coil through this relay to disable the vehicle as soon as power is applied to the charger. Once its removed, the vehicle will function properly.

Charger Contactor Control: This will be used to disconnect the battery pack from the charger when the charger is not charging. This is a 12-15V, depending on what the board is powered from.

Ethernet Connectivity: The control board includes a 10TBase ethernet connection for connecting the charger to a home network. With this you will be able to monitor the charger from the comforts of your house. This will also provide high speed networking communication to a BMS and other items.

Software Features:

The charger is designed for convinence. You will be able to program battery pack memory's for charging different vehicles with the same charger. So if you have a lawn mower with 48V Lead batteries you can set up a memory for that, then you can set another memory for you motorcycle and another for your car! All memories can be different chemistries also.

After that you can program different locations. Since the charger cannot detect the size of the circuit you have it plugged into, you have locations to limit current to pre determined levels. So you can have a home setting where you have a 30A 240V outlet in your garage, and the charger will limit input current (more accurately with AC sense board) to 30A. When you get to towk, you might have only a 15A 110V outlet that you can only effectively get 10A. Well you select the work location and the charger will limit current to 10A. You will be able to store up to 10 different locations as well.

Well thats all I can think of for now. I will add some more details as I remember them.

-Adam

[TheSGC]

That's a lot of features. Does your charger need any field testing?

[jackbauer]

Adam forgot to mention that this charger is also self aware

[Grimm]

The feature I would really like is a probe for hi-temp cutoff. I don't even use lithiums, but that's a big safety point for me. Also, more data for the ethernet connection (check whether you need to warm up the batteries in the winter before going outside)

[esoneson]

The BMS input, as noted by Adam, would satisfy this requirement.
Then you could have temp reading or voltage reading or whatever else the BMS supplies as info into the charger.

Eric

Originally Posted by Grimm

The feature I would really like is a probe for hi-temp cutoff. I don't even use lithiums, but that's a big safety point for me. Also, more data for the ethernet connection (check whether you need to warm up the batteries in the winter before going outside)

[Thalass]

Personally i'm not fussed about the UI. A multicoloured LED that goes green and blinky when the bike is charged will do me. Mostly because a bike has very little real estate for fancy screens and the like. Though perhaps if it sent a message (through wifi) when the charged was finished that would be neato.

My requirements are probably going to be different to most other people's because of the space restrictions a bike has. But i will eventually be going to north america so it'd have to accept 110v as well as 240v.

So for me it'd have to be flexible on the input power, simple to operate once set up, and physically small to fit on the bike. :P

[sawickm]

Originally Posted by adamj12b

I actually ordered the first prototype control board for the charger monday night. It should be here in a few weeks.
-Adam

Hi Adam,

It's been about a month since you ordered your Charger PCB, how's that project going ?

-Mark

[adamj12b]

Alright, Here is an update on the charger.

The boards that I ordered came in a few weeks ago. I had ordered the main control board, 2 different driver boards and a AC/DC digital isolated sense board. Heres a pic.

Untitled by AdamBrunette, on Flickr

The main control board has a graphic LCD panel that is 128x64 pixels. The user interface is super simple design. A rotary knob with push to select. You will just turn the knob to scroll to the option you want or increase or decrease values and then push the knob to select or set a value. Its very user friendly. The board is powered from a wide range of voltages. A switching power supply has been included to regulate from 9 to 24V down to 5V for logic. The input to the main board is traced over to the modular driver section. The driver requires an isolated dc-dc if isolation is required. The isolated dc-dc converter was not included on the main board because power requirements is dependent on the driver used. To have a universal dc-dc onboard would only increase costs. Also included on the main board is a 10-TBASE ethernet connection for remote monitoring and control of the charger. A real time clock (RTC) which will allow the charger to keep track of what day and time it is. This way you can set up charge schedules to limit the charging power or charge at all to times where power isnt so expensive or whatever reason you want. I also included the features I listed before. BMS input od 5V or 12V, Vehicle interlock relay featuring NO and NC terminals. Also a MOSFET circuit to control a contactor on the DC bus common to the dc supply to the main board.

The driver boards are modular in this design. I thought this could be good for people that want flexibility in power and price. You will be able to choose a high power driver, which uses the VLA-502-01 Powerex driver module. This is a 12A high frequency (30-70khz) driver module with built in dc-dc converter and Vsat detection. This is mainly for IGBT's.

The other driver board I designed and ordered is one just for prototyping. I will use this one to break out the signals for PWM, +5v, +VIN, GND, and an adc pin that can be used for feedback. I will use this board to design a driver based on what the cougar uses. It will be good for simple and smaller MOSFET based power sections.

The last board I ordered is the AC/DC sense board. My plan for this board was to use an energy metering IC for accurate measurement of current and voltage. Current is measured using a 0.001R shunt resistor while voltage is measured with a voltage divider and filter circuit. The board has an on board AVR to talk to the metering IC over SPI. It then converts this data and sends it over serial to the main board over an isolated connection. It is a very accurate method for measuring these sources, but it is not as fast as hall sensors. Due to the cost of this one and its speed, I will not be using this board as planed to monitor DC output from the charger. It will be an optional input for monitoring AC power only. The chip is more suited to this anyways. it can measure Power Factor, apparent power, reactive power active power and much much more.

Alright time for some pics.

Untitled by AdamBrunette, on Flickr


Untitled by AdamBrunette, on Flickr

Here is the back of the main board with the unpopulated vla-502-01 driver board.


Untitled by AdamBrunette, on Flickr

Here is a pic of the GLCD showing a map of the earth.

So I have tested all hardware functions of the main board. I have found a bunch of design charges that need to be made. Some are my mistakes in layout, others are things I would like to operate differently. Such as contrast adjustment. I will be changing to a different digital pot.

I am currently saving up to order the Alpha PCB's. Hopefully in the next few weeks I will have enough to order the boards and the new parts.

On the side of this project, I am working on a PFC power section. I wil post more on that when Ive made some progress.

[sawickm]

Originally Posted by adamj12b

The driver boards are modular in this design. I thought this could be good for people that want flexibility in power and price. You will be able to choose a high power driver, which uses the VLA-502-01 Powerex driver module. This is a 12A high frequency (30-70khz) driver module with built in dc-dc converter and Vsat detection. This is mainly for IGBT's.

The other driver board I designed and ordered is one just for prototyping. I will use this one to break out the signals for PWM, +5v, +VIN, GND, and an adc pin that can be used for feedback. I will use this board to design a driver based on what the cougar uses. It will be good for simple and smaller MOSFET based power sections.

Here is the back of the main board with the unpopulated vla-502-01 driver board.

Hi Adam,

Did you reverse engineer the VLA-502-01 Powerex driver module?

Is that your own DC/DC, or is the Driver PCB you have shown in your pictures based on the cougar driver power supply ???

Same pinouts as the Powerex VLA-502-01 PCB ???

Looking good !!!

-Mark

[adamj12b]

Originally Posted by sawickm

Hi Adam,

Did you reverse engineer the VLA-502-01 Powerex driver module? or is the Driver PCB you have shown in your pictures based on what the cougar driver power supply ??? Same pinouts as the Powerex VLA-502-01 PCB ???

Looking good !!!

-Mark

Hello Mark,

The driver module for the VLA-500 is basically the same circuit that they offer in the BG2A dev kit. http://www.pwrx.com/pwrx/docs/bg2a_application_note.pdf
It has some modifications to the board but not too many. I do plan to add hardware overcurrent protection like in the cougar as well. This will be good for those mishaps.

This will be directly on the main board so it can serve to protect the entire output. it wont matter what driver board is connected, because the pwm will stop before it gets to the driver.

-Adam