Electronic load simulating a battery

[Ross]

Hi All,

I have looked at a couple of bench top programmable electronic loads and can see that the would be useful to test power supply operation and limits, or characterize battery performance.

What I would like to use it for is simulating a battery when connected to a charger. I know I could simply use a battery for this task. A load would allow me to apply some protection (for over voltage or current). Also allow me to change to a different level of battery charge without having to use another battery or discharging the one I have.

So to my question, has anyone met an electronic load that can be configured this way?

Thanks

Ross

[xmo]

How about an Agilent Mobile Communications DC Source

"Simulate both Main Battery and Charger

Dual output models are recommended when you need to provide power as a replacement to your device’s main battery and when you need to simulate the battery charger power;

Use one output to connect in place of the main battery (which sinks current to simulate the main battery being charged) and use the second output to supply current to the battery charger input port."

[MosherIV]

This is a growing field since there is a lot of work around LiIon batteries.

Just search for battery simulator psu.

It may be possible to use an electronic load to to simulate a batter if the load can be controlled by a computer. The computer needs to read the current and provide a 'load' profile that simulates the battery charging profile.

The all in one solution provide this for you.

[H.O]

Are you trying to emulate a battery for a smartwatch or for an Audi e-Tron? In other words, what range of voltage/current are we talking about and what type of battery?

There are special battery simulators available but AFAIK they're for simulating/emulating the battery when it's discarging, ie powering your DUT - to test the DUT as it's being powered by the simulated battery. The Keithley 2281S springs to mind. Then there's the "DC communication source" that xmo mentions, or "Dynamic measurement source" like the 66312A etc, but I'm not sure if they can emulate a battery actually being charged or if they're only acting like a basic constant current sink.

While Goggling a bit I also stumbled across the ITech IT-M3400 but during my quick look around I wasn't able to find a manual to figure out what it can actually do.

Most loads have a list feature, have you looked into if that's something you can use?
Otherwise I suppose it would be possible to write a Python (or whatever) script to control the load based on a "model" of your battery.

I'll stop waffling now...

[Ross]

Thanks for your replies.

As I had my mind on charging only, I had not considered the other half of the process, discharge. So had not though to use the search term 'Battery simulator PSU'. Just fixated on load. This is what usually happens I don't think of the correct search term.

@xmo thanks, I will contact our Keysight rep.

@MosherIV, my backup plan was to use a computer to perform the logic, but the key thing I want is industry standard battery profiles. Otherwise if I do it then I could be testing against garbage.

@H.O Sorry I try to keep my post simple, but you are correct application size may would be useful. I am dealing with 7Ah SLA or lithium batteries.

[TheUnnamedNewbie]

R&S NGM series powersupplies could be ideal. A two channel model could model battery load and input source to the charger at the same time. They have specialized programs to model batteries with changing input impedances vs state-of-charge and all that.

[Ross]

@TheUnnamedNewbie, looks very cool, similar to the Keithley Series 2281S Battery Simulator

According to the following forum post the R&S  is ~US$4K. And a google search says the Kethley is about ~US$3.6K. Anyone know what to feed you goose to get golden eggs...

https://www.eevblog.com/forum/testgear/new-rs-2-quadrant-power-supply-ngm200-20aug2019/