Testing AC Power with a Regenerative Grid Simulator

Zachary Mazur Uncategorized Leave a Comment

TBEIC can help you test PV inverters and other AC power and frequency products with its regenerative grid simulator located in the Energy Integration Lab. So, what’s all the hype about? Why are startups along with small and large companies interesting in the NH Research 9410 Regenerative Grid Simulator? We’re glad you asked. This machine will help companies of all scales validate their product with peace of mind. Newly released advanced output control features, improved manual control interface, and comprehensive drivers are among the most popular tweaks to the new model. The 9410 can simulate several abnormal AC-grad conditions including: sags and swells, full cycles, sub-cycles, multi-cycle disturbances, and voltage harmonics. Three programmable channels that allow for any combination of DC as well as 1, 2, and 3 phase AC outputs make it perfect for level 1 and level 2 EV chargers, V2G, UPS testing, grid-tied inverter testing, and EVSE systems. The modular design allows for power increase in 12kW increments to simplify compliance testing such as IEEE 1547, UL 1734, CA Rule-21, and LVRT through elite integration and programming adaptability. While the machine is in the regenerative (sink) mode it will send return power back to facility mains rather than being dissipated as heat. NH Research hit the nail on the head with their 4-quadrant, regenerative, rack-mountable grid simulator.

How to be the Smartest Person in the Room

Sara Daugherty Uncategorized Leave a Comment

Advice for Energy Storage Novices Energy storage is new to me. Occasionally when people ask about my interest and background in energy I can say a few quick anecdotes so that I’m not completely dismissed. I’ve taken more courses than what is godly reasonable on environmental land use law so I know a lot about power system placement, nuclear waste storage, and the most fun of cocktail chatter: eminent domain. I used to hang out with people from IEEE because they were in and out of the planning school I attended and were OBSESSED with grid modernization. I had a short stint as an intern for an international development organization identifying solutions to Europe’s dependence on Russia’s natural gas. That’s about it. So, when I started at TBEIC, I’ve done what I’ve always done to be able to hold a conversation. I downloaded some podcasts. I’ve been a podcast evangelist for over ten years. It started when I was living overseas and needed a way to passively hear my mother tongue. It deepened as a Peace Corps Volunteer in Ukraine, where I’d download a few hours from itunes on to my ipod (remember those days) for 12+ hour train rides to Kyiv, Lviv, Kharkiv and Simferopol. Back home, they became my entertainment when I didn’t feel like being social and have escalated to the point that I have to have one on in the background regardless of what I’m doing. Over the past six months, as I’m becoming more acclimated to the work of TBEIC and its potential, the downloads have further increased in numbers. I find that I have little time or energy to read something and fully absorb it (says I as I type a blog post). I’d like to share some of the podcasts that have helped me transition to a new career in energy storage, the Internet of Things, and entrepreneurship: Startup Culture: This Week in Startups Hosted by Jason Calacanis, a founder, angel investor, and LAUNCH accelerator partner among many other titles is like a Muppet movie. He has factoids that are for the kids (newbies just learning how to get their evaluation together) woven in to sage advice for serial entrepreneurs. This Week in Startups is about an hour per episode and typically goes into one or two areas in great detail. Sometimes, companies pitch to him and then he gives immediate feedback. Other times he just rips Facebook advertising. What I like about this show is how its inspiring but also realistic, providing tough lessons when metrics aren’t being met. Recode Decode Not really a startup podcast but it’s one of the first I press play on when a new episode drops. Kara Swisher, a Silicon Valley journalist of Vox with a rich history of documenting the emergence of tech over the last three or so decades is an incredible interviewer. On the show she’s interviewed Elon Musk, Mark Zuckerberg and Mark Cuban along with executives across corporations, philanthropy and politics. What I like about Kara is she always says that tech founders could benefit from a good liberal arts education and boy do I find that ever so to be true. I find that often founders are pigeon-holed to be both masters of one thing and everything and this show pushes towards what is most important as a society in how and who gets to control technology. Coaching for Leaders I call this podcast my fake MBA because of how much I’ve gotten out of it over the past few years. It’s so powerful that it is one of the reasons I left my old job to start at TBEIC. Dave Stachowiak is a consultant who works with top-level managers to build their leadership capabilities and amplify their strengths. His show is typically under forty minutes or so and provides a mixture of interviews and advice. Through this podcast I’ve learned to speak with radical candor, delegate, better read people’s emotions and in general continuously improve. Energy Storage: The Energy Gang Greentech Media hosts this weekly overview on all things energy from policy to founders. Recently, the Energy Gang had an incredible interview with CEO Gene Berdichevsky of Sila Nanotechnologies, the creator of a lithium-ion battery that really put into context how hard it is for tech-enabled energy startups to get a footing and have a win within the first decade (I’m learning you should get excited around Year 12). This podcast also drives my LinkedIn searches to connect with people I must get to know and follow in the cleantech field. Experts Only This …

Batteries vs. Fuel Cells

Daniel Sylak Uncategorized Leave a Comment

Batteries and fuel cells are ever popular subjects in the ongoing conversation about how we power the world we live in. They are steadfast becoming important components of the energy chain to power things throughout our daily lives. Despite their rising popularity, many people are yet unaware of the differences between the two, their different use applications and why they are increasingly important in our lives. Batteries A battery is a cell or series of cells producing an electrical current through chemical reactions within the cells. Batteries are self-contained and will store a finite amount of energy that is depleted when the reaction reaches completion. Some batteries are intended for one-time use, while others may be recharged multiple times using an electrical source. Some common applications for batteries are consumer electronics like cellphones, car batteries and electric vehicles, pacemakers, emergency response radios, backup power supplies for servers and telephone exchanges and as a power source for off grid homes with inverters. Fuel Cells A fuel cell, like a battery, produces electrical current through a chemical reaction, but does so using a system in which a fuel (normally hydrogen, methanol, natural gas, and sometimes diesel fuel) is constantly supplied, and products (water vapor, sometimes CO2) are constantly removed. Therefore, fuel cells are direct converters of the energy derived from the fuels rather than a storage system for the energy like a battery is. Some typical uses for fuel cells are in vehicles as an alternative to combustion engines, backup power generators. Importance Despite the differences between batteries and fuel, they share one thing in common: they are both integral to the future of energy as we move away from fossil fuels. Both are gaining wider implementation in our daily lives, primarily when it comes to powering transportation, and are key to cleaner transportation. More Reading: Fuel Cells | Department of Energy How Do Batteries Work? | Northwestern Battery and Fuel Cell Technology | The Electrochemical Society References: https://opentextbc.ca/chemistry/chapter/17-5-batteries-and-fuel-cells/ https://chem.libretexts.org/Bookshelves/General_Chemistry/Map%3A_Chemistry_-_The_Central_Science_(Brown_et_al.)/20%3A_Electrochemistry/20.7%3A_Batteries_and_Fuel_Cells


Bill Whittenberger Uncategorized Leave a Comment

After spending considerable time trying various settings and operating strategies, I now have the inverter working, after a fashion.  Princeton Power has been only marginally helpful during the process, given that this is an old unit, out of warranty.  On thing they did tell me is that normally a 100kW inverter is connected to a battery bank of capacity around 200kW-hours.  My bank has capacity of only around 15kW-hours, or 7.5% of “normal”.  So I should expect some challenges. Knowing that my batteries were somewhat discharged, I decided to bring them to a full state of charge.  This would make my battery voltage as high as possible, and possibly avoid a low battery trip and allow the inverter to run.  Success!  The inverter locked into run mode!  Makes lots of interesting noises. Neither charging or discharging, the inverter claims a steady draw from the batteries of 4-5 amps.  Princeton says this is normal.  With my small battery bank, I will need to make sure I go to charge mode every hour or so to counteract this drain.  I also need to make sure that I charge before any shutdown, to make sure my inverter will re-start when needed. Now that the inverter is running, I need to interact with it.  So I need to get the LAN interface working.  This required many steps over several days, including locating the port on the inverter, running a cable to my laptop, purchasing a cross-over adapter, setting the IP address on my laptop LAN adapter, downloading and installing Java (needing to use IE, it doesn’t seem to work in Chrome??).  Thank goodness for Tyler, my IT helper.  Finally I can communicate.  It should be easier that this. The Princeton web interface works well, pretty much as described in the manual.  I can quickly change parameters.  More importantly, I can command a power flow to or from the battery bank.  From the panel interface, I was only able to command power to flow from battery to grid.  Not so handy when I have batteries that require frequent charging. When I command a 1kW flow from batteries to grid, I observe about 14 amps DC.  That’s more like 5kW.  When I command a 1kW charge, a see 14 amps the other way.  I also see in charge mode the battery box trip out after a minute or so because of a high voltage input. Clearly I have a calibration issue on the inverter on the DC side.  Amps reported by the inverter appear to contain a -0.4 amp offset compared to the amps reported by the battery box – easy to live with.  But voltage is quite wrong as measured and reported by the inverter.  Voltage as reported by the battery box is validated as correct by my hand meter in any operating mode.  In inverter idle mode, inverter reports a DC voltage about 6 volts lower that actual.  In run mode, regardless of amp flow, the inverter reports a DC voltage 40-50 volts below actual.  Yikes!  Princeton tells me that the box has gone out of calibration (no kidding) but I can’t persuade them to tell me how to fix it. I decide to work around the problem by adjusting the battery settings in the inverter control to much lower values – values that I would expect the inverter to observe in its un-calibrated form at max drain, hold, and max charge conditions.  Using these settings, I am now able to keep the inverter running for hours at a time. So far, I have been unable to have the inverter automatically switch to charge mode when battery voltage drops too low – I need to manually command a charge using the web interface.  When charging or discharging, I command only 1kW (and get much more) so that I do not exceed the amp rating of the system. Finally I have something that seems to work after a fashion, and might be used to conduct experiments, provided that one is respectful of system limits.  At one time I thought that I was going to need a different inverter, but it looks like we can work with this one.  A victory! One thing I notice about the inverter – the manual says that it should continue to power the critical AC load from the batteries if the grid power drops out, as long as the batteries hold up.  I should be able to get short time driving a 5kW load with my batteries.  However, when I …

Experiences with the setup of a micro-grid at TBEIC

Bill Whittenberger Uncategorized Leave a Comment

I have been engaged over the last 2 months with the setup of a small micro-grid at TBEIC, to be used for testing customer components that might be used in such grids. We have one customer who expects to test their intelligent breaker in a month or so using our setup. The three primary components that define our micro-grid are: – Powerhouse 25kW Load Bank, 480/3phase, load selectable in 5kW ranges, intended to represent a critical home or business power load that we do not wish to be disturbed when the utility grid fails. – Battery Bank for storage, includes safety, disconnect, and metering functions. Generously donated to us by a local firm who wishes to remain anonymous. The bank is made from 12 volt lead-acid batteries, 40 amp-hour rating, 32 total, about 1000 lbs of lead. Nominal bank voltage is 384 volts. Nominal storage is around 15 kW-hours. – Grid Tie Inverter, Princeton Power GTIB-480-100. This is an intelligent inverter rated at 100kW, meant to interface the 3 phase grid to DC storage, a PV array, and also a critical AC load. This 100kW box is very much over-rated for use with our 25kW devices. We use it because its what we have for now. Other equipment to be used in the micro-grid are: – Keysight PA2203A Power Analyzer, used for detailed characterization of 3 phase power – NHR 9410-24 Grid Simulator. This is a 24kW device that will manufacture any sort of power needed. Most importantly in this application, it can simulate interesting types of grid failures such as brown-outs, phase drops, line spikes, harmonics, voltage notches, and the like. – Keysight 34972A Data Acquisition System, used to capture data in real time. – NHR 9200 Battery Tester, used to charge/discharge/evaluate the battery bank off-line. All of the 3 phase AC equipment is fitted with what amounts to giant extension cords, which allows the equipment to be arranged in any electrical sequence. In the simplest arrangement, the inverter is plugged into and powered from the wall disconnect, and the load bank is plugged into the critical load connection on the inverter. And the battery bank is connected using a DC connector to the inverter as well. In a more complex connection arrangement, the following will be plugged together in order to power the inverter – wall disconnect, grid simulator, customer breaker, power analyzer, inverter. Commissioning of this micro-grid arrangement has provided a numbers of surprises and challenges that allow a good engineer to make a living: Powerhouse load bank – This was initially plugged right into the 480 wall disconnect to test its function. It also has a 110V cord that powers its logic and instruments that needs to be plugged in. As is happened, a wall plug with a GFCI was conveniently located. When both cords were plugged in (with nothing turned on) the GFCI tripped. The unit functioned as intended when plugged into a conventional 110 outlet. Hoping to avoid electrocution, I had some dialog with Powerhouse, which resulted in connecting the ground wire in the 3 phase cord to the ground stud on the box instead of the plug provided. Now everything plugs in without tripping the GFCI. But when you turn on the load bank, it still trips. Hmm. I decided to keep it plugged into the conventional 110 outlet and moved on, knowing that the case was grounded and that I would be safe. Grid simulator – Initially used this to power the load bank. Set up the control to provide 480 3 phase, turn it on. Turn on the load bank, it would draw power for a half second, then not. Hmm. Turns out that I needed low-side connections for each phase on the back of the simulator. Read the directions next time! After fixing this connection, the simulator has quickly and easily done everything I have asked of it. Power analyzer – next step splice this into the power supply chain to the load bank, and learn how to use it. This is a really nice unit, lots of buttons, touch screen, storage, graphics, and the like. After pushing buttons for an hour, the unit locked up. Very pretty screen, but no response to any of my inputs, including the USB from my computer. Off to Malaysia for repair, after extreme fun getting the connectors loose, and discovering that somebody has re-purposed my box. Grr. I hope to have this back in mid-Feb. Battery bank – This donated unit came with …