Toward a more resilient and flexible power grid

Toward a more resilient and flexible power grid
UW–Madison doctoral student Philip Hart (left), explains his research to visitors of the Wisconsin Energy Institute’s high bay lab (right). While much of Hart’s daily work requires only a powerful computer, he uses the lab to verify control algorithms for a dynamic distribution system (DDS).

"The biggest and most complex machine ever built by humankind." That is how University of Wisconsin–Madison doctoral student of electrical engineering Philip Hart describes the nation's power grid.

Hart and UW–Madison electrical and computer engineering professor Tom Jahns are part of a research team charged with the formidable task of transforming that big and complex machine from the inside out.

Hart says such a transformation will be necessary to allow for the seamless integration of renewable energy into the existing grid.

"Solar and wind technologies will be scaled up the most going forward," Hart says. "The main reason is economics, as the cost of solar photovoltaic (PV) rooftop panels has fallen precipitously during the past few years."

So why is it challenging to integrate many dispersed, or decentralized, small-scale power sources into the current grid? One reason is that solar PV generates a different type of electricity than traditional, utility-owned power plants whose generators connect to consumers by long transmission lines.

"This network of line-connected machines acts like a system of springs, masses, and dampers," Hart says. "When you disturb the springs, the masses will jump around, but usually reach their equilibrium again pretty quickly. Solar and energy storage technologies, however, are often interfaced by inverters that may react to disturbances in very different ways."

Inverters convert DC (direct current) electricity – the type generated by solar PV and batteries inside computers and cell phones – to AC (alternating current) electricity, the kind that forms the basis of today's .

To integrate more inverter-based distributed generation into the grid, the researchers are developing a dynamic distribution system (DDS) that supplements centralized power plants, instead of replacing them.

A DDS consists of many functional clusters of energy-generating sources and energy-consuming loads. Each functional cluster has its own controller, and may even be able to function autonomously, but all clusters communicate with a higher-level controller via interconnected computers.

The DDS has several benefits: it is more resilient, with a smaller likelihood of system-wide blackouts, and better suited to providing combined heat and power, which boosts its efficiency. "It is much easier to make use of waste heat when the energy source is right next to your house, compared to a fossil fuel-powered plant at a distant site," Hart says.

Distributed generation and control is also better than the traditional grid at managing the intermittent nature of . When the sun stops shining or the wind stops blowing, a small generator or energy storage source can ramp up electricity production much faster than a large plant, and ramp down again when renewable sources return.

"The great thing about the DDS is that it can be implemented incrementally," Hart says. "That minimizes required infrastructure changes and will help keep electricity affordable. Our long-term goal is for the DDS to be a more resilient system than the current grid that deliver benefits to both utilities and customers."

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Citation: Toward a more resilient and flexible power grid (2015, December 15) retrieved 21 July 2019 from
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Dec 15, 2015
One of the great cyber jobs in the near future will be working on this transition. If you code, go for it. It won't be easy at first.

Dec 15, 2015
Here is an entire city of SCARED Deniers, and you can discover their "reasons":


Typical conservative logic.

Dec 15, 2015
I see Ira still follows me around to award me "ones" because I beat him at his own game. He seems to be unable to debate technical issues.

This one is a serious opportunity for coders. The next revolution in energy systems is upon us, and it is being designed now. Those who do it should also be engineers with significant knowledge of the technical specifics of AC power distribution and transmission, plus the ability to integrate significant numbers of inputs. This (above) approach seems best.

Dec 15, 2015
I see Ira still follows me around to award me "ones" because I am the couyon and moron.

Oh yeah, that's why he does that.

Dec 16, 2015
With home storage and PV systems we can have an internally-supplied microgrid connected to the others just like we planned years ago. Nobody listened then, when folk designed neighborhood external combustion expanders driving generators.

Giving us neighborhood power makes us more independent, gives more reliability, and is more efficient, as well as efficacious. Read E.F. Schumacher's "Small is Beautiful".

Dec 16, 2015
neighborhood external combustion expanders

You might being trying to sound all Senior Engineer like with that. But to us it sounds like a little kid playing pretend to be the Engineer in the backyard. What I mean? Well I mean it is just a little too much.

Read E.F. Schumacher's "Small is Beautiful"

The library don't have that book and I am not buying him on your say-so Cher. Not that I don't trust your engineering judgement. I just don't trust you not to recommend something that is all new-agey and hippy-like and not very practical or useful. Is he who you got the "neighborhood external combustion expanders" thing from?

Dec 16, 2015
Gosh, if you just lo0oked it up, you would not sound so helpless. You will like it, I think.

A friend of mine with a PhD used a lot of computer time to design the expander, back in the late 1970's at Lawrence Livermore Labs. It was a flat, x-shaped horizontal engine with different size carbon pistons to balance out the loads on the four stages of expansion.

Dec 16, 2015
Gosh, if you just lo0oked it up, you would not sound so helpless.

Well gosh back to you Skippy. If you would look it up first before you postum you would look not sound so hopeless. Because unlike you do, I do look up the silly stuffs you post up sometimes.

Go right on ahead Cher. Try him. Google up: "neighborhood external combustion expanders". Google seems to think that is a rare silly thing too.

You will like it, I think..

Can't like him if I can not find him. But if you would like to double down I am not too busy. But if you are going to use something that is not "neighborhood external combustion expanders", then don't bother because you are still the moron.

Dec 16, 2015
Please stop playing dumb. I was referring to Small is Beautiful.

Is it an act? Or what?

Try this:


Dec 16, 2015
Please stop playing dumb. I was referring to Small is Beautiful.

Is it an act? Or what?

Skippy, why do you think I did not already look that up too? How you think I knew it was new-agey hippy stuffs when I said that?

That couyon has been dead for 40 years and if his ideas have not caught on by now, well it will probably only catch on with really old new-agey hippy types. His stuffs did not work, they still don't work except in little towns and communes. And they are not going to work where you have millions of peoples crowded into great big urban areas. It's sky-pie stuffs that only new-agey hippy types still see as being "just around the corner". Just around the corner for a 70 plus year old goober like you better a lot more quicker than it has been, eh?

40 years ago, and you are only about 1/10 the way there, so that means just around the corner is about 400 years from now. Smart money would be getting the world population down by half.

Dec 16, 2015
I guess you didn't read it.

Here is the entire thing, free, for anyone with a more open and educatable mind.


Dec 17, 2015
Here is another look at the future, already in the present:

It also proves Schumacher correct. Those who dismiss him without reading him are not intelligent, but prejudiced.

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