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  • Writer's pictureForsspac Team

DDRUPS System. A Q&A with our Technical Director, Phil Thoburn.

In this Q&A, Robert and Phil Thoburn discuss the DDRUPS system alongside the types of business and industries where installation can be highly beneficial compared to other UPS systems.


Rob: Hello, my name is Robert Thoburn of Forsspac, today I'll be talking to my brother Phil who is our Technical Director.

Rob: What does DDRUPS stand for?

Phil: Diesel Dynamic Rotary UPS or uninterruptible power supply.

Rob: And what are the key components within that device?

Phil: Well it starts with a large mass which is the inertia, an alternator and a generator. The mass sits generally between the alternator and the generator, and it provides continuous rotating force.

So, the alternator is always rotating under its own power from the other power supply, and when the power fails the inertia of the mass keeps the alternator running while the generator is running up. Typically a generator starts in five to 10 seconds. So the mass has got to be able to carry the generators of the alternator itself at enough speed, enough velocity, to keep the output going during the time the engine is starting up. So, those are the three basic components.

And beyond that, there are some fairly fancy controls that keep it working properly.

Rob: Yes, well we would certainly have to have control systems in life, there wouldn’t be life without them.

Phil: You couldn't do without good high quality control systems.

Rob: This is true.

Phil: There is there is an alternative version of this where the mass and the alternator is separate from the actual generator itself. We've seen this, and that tends to be a slightly quieter unit which is interesting, but the majority of the units we've seen are inline, engine, mass and alternator.

Rob: Ok, so do these devices, DDRUPS do the same as a battery pack UPS?

Phil: They do slightly more, that is what I would describe it as. Typically if you're feeding say a data centre within a building, you have a small scale static UPS system, which is a battery based system.

You have the electronic inverter, typically it's online, so you have the power coming in passing through the batteries, back out through an inverter and powering up the equipment. So that's a static ups system. It's usually limited in size and capacity, to handle just the data centre you're feeding the power too.

With a DDRUPS, the key difference is that you've got a fuel source so you can keep it going essentially indefinitely as long as the fuel lasts. The other key difference is you have a rotating component, the alternator. This rotating component is really important in that you can use this to clean up the power supply. So what you're doing is using it as an active filtration and power factor correction device.

So, you actually do end up saving money as compared to the static UPS, all the UPS can do is take the incoming power and create an outgoing waveform. So that does clean it up, but doesn't actively suppress noise further down the line.

Rob: But in by clean up I'm assuming you mean harmonics to manage cable sizing and stuff?

Phil: That's correct, and obviously losses on the neutral return.

Rob: And, what’s the typical life comparison between the battery backed up UPS and a DDRUPS.

Phil: That's actually really good question.

Batteries have a life for three to five years essentially, they are usually lithium iron batteries that need replacing periodically.

The DDRUPS system has a very significant life, it probably needs some renovation every 10 to 15 years so your bearing changes to be done, but in essence it should last the life of the building.

Rob: That's pretty good news I mean, that certainly seems to making a good case for investing in DDRUPS rather than battery backed up UPS’.

Phil: It certainly does, but I think what's interesting on the comparative side of this, in certain building types particularly in casinos where you want to give the clients who are actually the occupants of the space, a better feel for the space or a better experience.

Putting DDRUPS in allows you to expand the capacity significantly, so where you might only otherwise supply the data centre and perhaps the gaming machines, in this case you can keep the entire gaming floor live because the incremental cost per kilowatt of a DDRUPS system vs UPS is lower. So, you can actually end up with much bigger UPS system for the development, giving your guests a much better working experience, if there is a chance of power outage, they never see that.

Rob: Well that's pretty cool, that's pretty cool.

Rob: So is the DDRUPS applicable to other environments like an industrial environment maybe a chip fab manufacturer or something like that?

Phil: Yes, in fact the current usage of DDRUPS in the Philippines is in industrial, and Texas Instruments in Clark have DDRUPS supplying their production floor.

Rob: Okay, one final question. Can DDRUPS be retrofitted into buildings?

Phil: There will be challenges in doing that but it's not impossible.

First of all they are larger in size than a generator, so if you wanted to replace your generator with DDRUPS you can but need a bigger plant room, they're quite a lot longer because of the extra componentry involved. If you wanted to break a building into say two sections, one part with DDRUPS, one part with generators­. You've then got to have an adequately separated electrical distribution system on the low voltage side to allow you to break it up in that fashion. So, that could cause you some difficulties in doing it. You know obviously nothing is impossible, but certainly there will be challenges involved.

Rob: Okay, well Phil thanks very much indeed for answering my questions I really enjoyed the answer so thank you for your time.

Phil: No problem at all, thank you.

If you wish to find out more regarding the DDRUPS system, feel free to get in touch to arrange a chat with our expert team.


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