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Episode #104: 'Conditional Monitoring & Generator Maintenance Without Downtime' with Steven Turner, Senior Engineer at Arizona Public Service [an Energy Central Power Perspectives™ Podcast]

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The ‘Energy Central Power Perspectives™ Podcast’ features conversations with thought leaders in the utility sector. At least twice monthly, we connect with an Energy Central Power Industry...

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  • Dec 6, 2022

A main focus on note in the utility industry that's been gaining headlines more and more has been grid reliability and ensuring that no matter where and when energy is needed that the power sector is able to provide it. While some of the challenges in this arena come from unexpected events like extreme weather or equipment failure, another source that must not be overlooked is from planned maintenance. Equipment needs to be powered down regularly to perform fixes and upgrades, but taking those assets off the grid needs to be carefully timed so the aggregate flow of power can continue humming in the direction it's needed.

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Managing such planned outages is critical not just for the customer to get their power but also so utilities aren't losing too much money in the meantime. These needs combine to make the topic of this week's episode of the Energy Central Power Perspectives Podcast so exciting, and that is via conditional monitoring of assets and performance of necessary generator maintenance without needing to plan for wider outages. Steven Turner, a Senior Engineer at Arizona Public Service, has been advancing new techniques and technologies to advance this field, a topic he recently addressed at the IEEE Annual Conference. For those who were not able to attend live, Steven joins podcast host Jason Price and producer Matt Chester to share the crucial message and speculate on how these advancements can improve the utility sector in the coming years.

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Thanks to the sponsor of this episode of the Energy Central Power Perspectives Podcast: West Monroe.  


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Jason Price: 

Hello and welcome to the Energy Central Power Perspectives Podcast. This is the show that brings together leading minds and energy to discuss the latest challenges and trends, transforming and modernizing the utility industry of the future. And a quick thank you to West Monroe, our sponsor of today's show. Now let's talk energy.

My name's Jason Price, Energy Central podcast host and director with West Monroe. Coming to you from New York City. And always I'm joined by Matt Chester, Energy Central podcast producer and community manager dialing in from Orlando, Florida.

Matt, when it comes to advances in the generation side of energy, the focus has largely been on how to transition from one energy source to another. But from a utility business standpoint, a critical topic of importance is how to keep generators running at all times to maintain the high quality electron flow to the grid and overall performance. These utilities, scale generation systems are massive in size and the workhorse of utilities generation mix, they don't just operate from the click of a switch as we may like to think. So Matt, can you give us a bit of a background on this topic for our audience?


Matt Chester: 

Well, Jason, I don't know that I can give as good of a background as our guest will be able to do, but like you said, customers expect that they can flip the switch and there's no question that they'll have power coming from their systems. This instantaneous demand must be met every step of the way with supply.

And as the power mix continues to add intermittent renewables as well as dispatchable central power plants, as these assets stretch further across the globe and that as central generators experience outages, both expected ones for maintenance and unexpected ones from asset failure, the job of ensuring that the grid stays humming reliably and without question from the customer is what makes the utility sector so complex these days. But our guest today is one of the experts working on yet another solution that can help ease these challenges.


Jason Price: 

That's great. And yeah, you're absolutely right. Our next guest will have a lot more to add to it, and I'm sure you've generated a lot of interest that will power our discussion. Sorry Matt, I couldn't resist. As Matt described, maximizing both power reliability and utility profits is indeed top priority to making this whole system work. But unexpected events come up all the time that create disruptions and interruptions. But if those hiccups can be anticipated and ultimately prevented, then that becomes a huge win for the utilities. Our guests today has brought about a groundbreaking way to advance these principles through data collection and tracking. On the generation side, we more often hear about such practices on the T&D aspects of the power sector.

So, the possibilities he's opening up can indeed be quite valuable. So, joining us today is Steve Turner, a technical leader and protection pioneer at Arizona Public Service. And recently he shared the results of his pioneering work at the IEEE Power System Relay Committee. And we want to get a deep dive into operating and maintaining the health of a generator, a system that we so much depend on in our everyday lives. So, let's bring him into the podcast booth, Steve Turner of Arizona Public Service. Welcome to the Energy Central Power Perspectives podcast.


Steven Turner: 

Howdy and thanks for inviting me.


Jason Price: 

Absolutely. And we're thrilled to have you on. So Steve, before we dive into this topic, I'd love to hear more about your journey in the utility sector. How did you get started in energy and what does this role with EPS entail?


Steven Turner: 

Okay, so when I was undergraduate, I went to Virginia Tech, which is a very good engineering school, and I decided to go into electrical engineering. And as an undergraduate I wanted to pay for as much of my education as I could. I was a co-op student with Dominion at the time, with Dominion it's a very good electric utility. So that got me exposed to the electric utility industry. And then, my junior and senior years, we had a professor come, his name's Dr. Aaron Phadke, and he became in charge of the power program there. And he is a amazing individual. He was a pioneer behind laser measurement units and all kinds of stuff. And I know the first class that I took with him my junior year was transmission line theory. And he just blew my mind and it was like I was undecided what I wanted to do with my career.

But taking that class with him really made me decide I wanted to go into the power industry. And then, he is an expert on protection, so he had a protection course. So, I took all those classes. So, it's a long road. I wanted to work for electric utility when I graduated, but I went back to graduate school and I got a master's in electrical engineering. And then, I studied steady state stability. And I did a project on that, where we were actually looking at the Florida at one time had stability problems with the rest of the country. So, we actually did a project where we installed some equipment at the northernmost border power and light 500 KD substation. And we were able to actually do a real-time assessment, say there was a fault on a 500 KD line, would Florida, would it remain stable or would it go unstable?

So, that was really fun. And then I got a job, I went to work for a British relay manufacturer, so I got to work with utilities all throughout the US. So, I started my career, I was really focused on transmission line protection, which is very exciting because that's very complicated and it's just very interesting protection. And I did that for a long time. And I ended up finally, I got an opportunity to work for a utility. I went to work for Duke later in my career and I started off in transmission and I was in the Carolinas and they had a position to come open, interested in Florida. So I went down to Florida again, I was working in their transmission department doing system protection. And by this time I had well, over 15 years experience under my belt, I was considered an expert on transmission line protection.

But this project came along. This is typical for most electric utilities. The generator protection is typically handled by the transmission department, by their system protection department. Most utilities in the US, the generation department, they don't handle the protection. It falls to transmission. But anyway, so a generation protection project came and there was another protection engineer there who he was very experienced, very smart guy, and they gave the project to him. And I could just see that he was very stressed out about that project because he had basically no knowledge on generator protection. And that was something that caught my attention. And I thought about that. And then, I knew that Beckwith Electric there in Florida, they make generator protection products. So anyway, I knew transmission really well and I thought to myself, "Maybe it's time to for AC change and maybe I need to try to learn more about generator protection."

So, I was able to get a job with them and I worked there for 15 years. And generator protection, there's not a lot of people that compared to like T&D, there's just a small number of people that are familiar with how generator protection works. So, being there 15 years, I learned it really well. And then segueing into Arizona public service, they actually contacted me and recruited me and they wanted me to be in charge of their system protection. They were had decided, their generation department had decided that they wanted to do the protection themselves and they wanted me to head that up. And it was just too good of an offer to pass by.

So, I went there and I've been there going on four to five years now. And I came at a really good time because we have a lot of projects where we're updating the generator protection equipment at a lot of our power plants. So, I was able to create a new standard and I've been very instrumental in that. And it's really been fun, a lot of fun. I really love working the job that I have now. I feel appreciated.


Jason Price: 

So perfect. Steve, I'm going to jump into, this is a great segue to my next question. So first of all, I think we need a quick definition from you on what is it meant by generator protection? And then second as a follow up is really share with us like a high level. What was the main message that came out of the presentation you gave at the IEEE? So go ahead.


Steven Turner: 

Okay. So for generators, we have these large generators. I'm sure you've seen generation plant when you're driving around, the bulk of our power comes from these generation plants. So you'll have these large generators, they could be a 100, 200, 500, even. We have Palo Verde, that's a nuclear power plant. I work with them too. And they have generators that are over a thousand megawatts. So, that's the bulk of our power system where we get our power sources. Renewables are really big thing, but it's not going to replace the plants anytime soon if ever. So these generators, you can have abnormal conditions occur, which I won't go into detail, but say a particular abnormal condition occurs, then you need to get the generator offline and shut that generator down to prevent damage coming from it, say a transmission line, say a lightning bolt strikes a transmission line.

Basically, what the protection does is it opens the circuit breakers at each end of the transmission line. That would be two substations, de-energize a line, the lightning strike is gone, and then they reclose in, they reclose the line back in and bam, everything you're right back to normal operation. It's not that way with the generator or for generator gets tripped offline, it's not going to be coming back on time. It's not going to be coming back online anytime soon. You have to find out what was the root cause, was there any potential that there was damage done to the generator. And then you have to get all that squared away and make sure that the generator is okay and then you can bring it back online. So, it's a much bigger deal whenever the generator protection operates. So, the protection is their relays, their computer relays, they are monitoring the health of the generator and they can quickly detect when something is wrong and they will trip breakers, take the turbine off and do whatever's necessary to isolate that generator.

Okay. And then going into IEEE, that's the Institute of Electronic and Electrical Engineers, they have a group called the Power System Relay Committee. You have to be invited to be a member of the group. So, that's something I'm very proud of that I was invited. But they have to have committees. One subcommittee is rotating machinery that obviously covers generation. So anyway, I had said earlier that the protection that we use for the generators, they're basically computers. So, you have all of this digital information inside of these devices. And I just feel like if you're familiar with condition monitoring that by taking this data from the relay and mining it, it's possible that we can do trending and determine if a problem is developing.

And that means that you don't wait until the problem occurs, but that you're seeing that a problem is slowly developing over time. So then like generators, they typically run most of the year and then they'll be, say a month, they take the generator offline and do maintenance. So, if we have these type of monitoring algorithms, then what we can do is if we see a problem is coming when the maintenance is scheduled, we can examine the generator at that time to see if yes, there is something that going to happen and we can take steps to mitigate that. And again, accreditation at the last committee meeting and it was very well received.


Jason Price: 

That great to hear. So I want to ask you, there's a term, some terminology here that's new to me and maybe you can help define it for our audience, assuming that it's maybe new to them as well. But I also want you to take it a step further and basically translate what does this all mean for the health of the system and the term I'm referring to is, and you told me this in the prep call that we had that tracking of capacitance. So, what exactly is the art of tracking capacitance? And again, how does that translate to monitoring the health of the generation system?


Steven Turner: 

Yeah, okay. So I mean to really know what capacitance is, it helps to be an electrical engineer. But anyway, it's an attribute of the generator. Think the best way to think of it is when you have a generator, you have a stator winding. So that winding could have hundreds and hundreds of turns. You have the rotor spinning that induces the voltage on the stator, which then makes power. The power flows out of the generator into the transmission system. So, there's a certain amount of capacitance associated with that stator winding. So the stator has two ends. One end is the neutral end, and that's where it's grounded. And then the other end is that that's where you connect it to the power system. So basically, that capacitance is a parameter that is from the winding to ground. So, it's a distributed parameter, so you have so much capacitance per turn.

So anyway, what you can do is to mathematically model it, you could split the total capacitance, you could put one half of the total capacitance at the terminal side of the generator, and you could put the other half at the neutral side of the generator. And now, so what happens is over time the capacitance, it has a fixed value, but that value can change based on things such as contamination. So, if the capacitance starts to get contaminated, that could be say water possibly. Then, the magnitude of the capacitance will increase over time. So, we recently installed a new computer relay for one of our generators at a local plant here in Phoenix. And it takes measurement voltage measurements that by looking at those voltage measurements, you can actually determine what is the value of total capacitance at any particular time. So you have, what you do is you have a database, so say day one is the first time you do that measurement.

So, you take that measurement and then you just do it periodically over time and you just look to see is that value of capacitance increasing over time? If it is starting to increase that, you probably have a problem developing. So that's basically, that's how it works. Without getting into the nuts and bolts and all the theory, that's like a very high level way of explaining how it works and what the beauty of this is, you can take these measurements at any time when the generator's operating, whereas otherwise, the only time you would be able to do it is during maintenance is when the generator is offline, which is, that could be... Utilities have different periods or between times when they take a generator at a service to do maintenance. So, being able to do it continuously on a day-by-day basis if you wanted to versus one time per year. I think you could see the advantages of being able to do it on a continuous basis versus once every one or two years.


Jason Price: 

Yeah, I understood that. So, let's just put it this way, not having those signals, you run the risk of it breaking down when you least expected it. So, it sounds like the strategy you've created has helped with some of the monitoring and you're reporting on the health of the generation system long before it breaks down, which is just so critical and so key to keeping things, keeping lights on basically. So, given all this, why aren't more utilities adopting these kinds of practices that you've helped develop?


Steven Turner: 

Well, let's say we have the generation department. I'm in the protection group. There is monitoring equipment that's installed on generators, but that could be unlike other people. And anyway, so this is just another tool that we have our disposal. And what's nice about it is that we can remotely communicate with that relay so that we have access to this information at any time. So it's just, like I said, measuring the capacitance is something that they can't really do until now. It's when the generator is in a maintenance mode. So this is something, it's a new tool that people will have that they can use that they didn't have before.

Most problems that happen with generators, there's all kinds of things that can happen, but the most common problems that you have are related to the stator. This is a really good thing to measure because so many times when there is a problem that is related to the stator.


Jason Price: 

Yep, okay. So there's got to be a change management component of this. So it's really just sort of changing some of the work processes that have been established for a long time. So I'm curious, what's been the general feedback from the audience when you gave this presentation? They still deliberating on it. Is it been now being worked into the plans of utilities? I mean, just what's the general feedback you've heard from your peers in this space?


Steven Turner: 

Well, what I would say is this is something that when we release a report, the utilities will have the opportunity to read the report. It will outline how the technique or the algorithm works and other utilities that they wanted to adopt that they could do it themselves.


Jason Price: 

Got you. All right. So then I guess it sounds like the next steps of all this is really just letting the industry of absorb it and see how best to integrate into their processes in one form or another. Is that the general idea?


Steven Turner: 

Yes. And also I was at Western Protective Relay Conference, October of this year, and I gave a presentation. It wasn't just on this, there was other things I talked about as well, but that was kind of one of the main topics. It was very well received there as well. And you have electrical engineers, protection engineers from all over the US and outside of the US attending. So, it was very well received there as well.


Jason Price: 

That's great. Well, congratulations on developing this bit of pioneering innovation for the industry. It's no doubt even going to be more critical, especially as weather events, bad actors and other sort of outside forces, including internally to raise potential risks and create potential risks on our generation system. So congratulations on the accomplishment that you've made. Sure it's going to continue to be well received in the industry and something that I would expect would be adopted wide scale at as the technology continues to mature in the marketplace. Okay. So with that said, Steve, congratulations there and congratulations for making it this far in the podcast. At this point, we were going to pivot to what we call the lightning round, which gives us an opportunity to learn more about Steve Turner, the person rather than Steve Turner, the professional. We have a series of questions, five questions we're going to ask you, and we ask you to either give a one word or one phrase response. So are you ready?


Steven Turner: 

Yes, sir.


Jason Price: 

Okay. What is your all-time favorite movie?


Steven Turner: 

Probably Immortal Beloved


Jason Price: 

Best way to unwind after a long day,


Steven Turner: 

I like to go out and have a beer and watch a football game.


Jason Price: 

What's your best tip for giving presentations to an intimidating group like those at the IEEE?


Steven Turner: 

Okay. It's more than just a phrase. Basically, you have to know your subject very well, and you have to be confident. And if you know your subject very well, then you don't really have anything to worry about. Nobody's going to be able to ask you a question that stumps you or they find some hole in your logic. So, it's all about being well prepared. And I'm very lucky that throughout my career I had mentors that were excellent at giving presentations and they shared their presentation skills with me. So, putting together the presentation, what you're going to present and how you present it, that's a big part in being giving a successful presentation.


Jason Price: 

Who are your role models?


Steven Turner: 

Dr. Aaron Phadke was my first role model and he was my professor when I was at Virginia Tech. The next mentor I had, I only had it for a week, but his name is J Lewis Blackburn. He, at one time was the chief application engineer for ABB in Westing College. Before that, I took a course with him when I was very early in my career. And the people in the course were young, I was like, say 25, 26 at that time. And a lot of the other students were protection engineers that worked for other utilities. And we just had himself and I had a lot of amazing conversations, technical conversations, and I just realized that I could do a lot more with my career at that time. And it changed me. When I came back from that training, I was a different person and I wanted to do a lot more with my career, after that.

I said I worked for a British relay manufacturer. I had three mentors there. One was the person that was in charge of, we had an office in New York City, so we would service our service territory was the US and he is excellent protection engineer. And also, he has excellent presentation skills and I learned a lot about how to present from him. And then the factory that was located in England, the chief development engineer and the chief application engineer, I mean these guys, I say they were genius level between the two of them, there was no question, question that I could ask that I would not get an amazing answer. And they would give very thorough answers so that if you asked them a question and you phrased it well, they would answer it in such a way as that you would understand. And then after that, I'm just thinking then when I worked for Beckwith Electric, Dr. Murty Yalla, he's a fellow in the IEEE.

He's another amazing person. And I just learned so much about generator protection from him. He was another mentor that I had. And I would say those gentlemen were the ones that really had a very strong influence on my career and being successful in getting to where I am today. This is one thing I'll just say for young people, it's really important to know what you want to do with your career. And the best training you could get is on the job. And anywhere I ever worked, I would always try to find out who is the most knowledgeable, and I would ask lots of questions. You just can't wait for people to come to you and they're going to explain everything. And it really doesn't work that way. You have to be active in seeking out mentors.


Jason Price: 

Very true. And finally, in the question we ask most of our guests, if not all of them, is what are you most passionate about?


Steven Turner: 

I'm very passionate about my career. It is a job, but it's also, it's almost like getting paid to do a hobby. I love protection. That's fascinating. And it's, you can always keep learning more. And I'm in a position now where I'm starting to be a mentor to young engineers here at APS, which is a fantastic situation to be in. So, my job is one of the things that I really love. I also have another hobby. The game that I play, it's a table cup game, but I think it's really important. For a long time, I was just really focused on my career. I did mountain climbing for a while. That was a big thing, but I finally got out of it to this very dangerous, but that was something that was really a big thing in my life. But it's important to have something outside of your job that is really important to you and you get a lot out it, you just don't want to be, if you know "All work and no play makes Jack a dull boy," is a very true statement.


Jason Price: 

That's right. And everyone needs some balance in their life, no doubt. So, congratulations again on the recognition in the industry and congratulations on getting through the lightning round. And so now at this point, we want to give you the final say. So, knowing that you've got peers in the industry listening, what are some of the takeaway messages you'd like them to take away and resonate with?


Steven Turner: 

I would just say that I follow a technical path and I always want to keep learning how to do new things and not just rest on my morals. I want to keep learning new things. I think that's really important. And one thing I've done recently is I've enrolled in an online graduate program and artificial intelligence. I think that's the next big thing that's coming to the electric utility industry. So, if I'm successful, then I think that I'll have another skill set. And this goes back to that project that I worked on where we were measuring the capacitance of the generator data winding.

So, always look for new things to gravitate towards and learn new things. And if you do that, it never gets stale. And I would also like to say, it's like I've seen some engineers, it's like they get in a comfort zone. This is what I've seen for a lot of utility engineers is, you just kind of get in your protection zone. You don't get in the zone of this is what I'm responsible for and you know, kind of get cubby hold and I don't think that's a good way to... If you want to keep making advancements and reaching new plateaus, if you've just defined what your responsibilities are and you don't want to learn new things, you're never going to advance. So, it's really important and look for new ways to do things and even get involved in new technology.


Jason Price: 

Never stop learning. Well stated there. All right. So Steve, this is a great conversation and we really appreciate your insight and by the way, taking complex engineering language and methods and you did a nice job turning it into everyday language for commoners like myself to understand. So, I want to thank you for that. It's not an easy skill to have and you clearly mastered it. So, I want to thank you again for joining the podcast and speaking to our audience, your peers, and we hope you consider coming back maybe a year from now to see how things are developed and see how your innovation has adopted in the industry. So, thank you again for this fascinating discussion. We appreciate it immensely.


Steven Turner: 

Well, you're welcome and thank you for inviting me to participate in this.


Jason Price: 

And you can always reach Steve Turner through the Energy Central platform where he welcomes your questions and comments. And we also want to give a shout out of thanks to the podcast sponsors that made today's episode possible. Thanks to West Monroe. West Monroe works with the nation's largest electric, gas, and water utilities in their telecommunication, grid modernization, and digital and workforce transformations. West Monroe brings a multidisciplinary team that blends utility, operations, and technology expertise to address modernizing aging infrastructure advisory on transportation, electrification, ADMs deployments, data and analytics, and cybersecurity. And once again, I'm your host Jason Price. So, plug in and stay fully charged in the discussion by hopping into the community at energycentral.com. And we'll see you next time at the Energy Central Power Perspectives Podcast.


About Energy Central Podcasts

The ‘Energy Central Power Perspectives™ Podcast’ features conversations with thought leaders in the utility sector. At least twice monthly, we connect with an Energy Central Power Industry Network community member to discuss compelling topics that impact professionals who work in the power industry. Some podcasts may be a continuation of thought-provoking posts or discussions started in the community or with an industry leader that is interested in sharing their expertise and doing a deeper dive into hot topics or issues relevant to the industry.

The ‘Energy Central Power Perspectives™ Podcast’ is the premiere podcast series from Energy Central, a Power Industry Network of Communities built specifically for professionals in the electric power industry and a place where professionals can share, learn, and connect in a collaborative environment. Supported by leading industry organizations, our mission is to help global power industry professionals work better. Since 1995, we’ve been a trusted news and information source for professionals working in the power industry, and today our managed communities are a place for lively discussions, debates, and analysis to take place. If you’re not yet a member, visit www.EnergyCentral.com to register for free and join over 200,000 of your peers working in the power industry.

The Energy Central Power Perspectives™ Podcast is hosted by Jason PriceCommunity Ambassador of Energy Central. Jason is a Business Development Executive at West Monroe, working in the East Coast Energy and Utilities Group. Jason is joined in the podcast booth by the producer of the podcast, Matt Chester, who is also the Community Manager of Energy Central and energy analyst/independent consultant in energy policy, markets, and technology.  

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