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This section of the site contains small articles that I have written, "weblog" and "journal"-style links and entries, and other such miscellany.
Vacation Pictures
27 October 2004
My dad, my uncle, my cousin and myself took a little vacation to the Keweenaw over a long weekend in October since we didn't get a chance to go there this summer like we usually do. I had lots of fun as I always do when I visit the Keweenaw, but this time there were a few extra fun things going on, such as a big snowstorm blowing in, the region's power grid undergoing a cascading failure, and so on. I had borrowed a Canon SLR digital camera (an EOS 300D) and was testing it out over the vacation, so I took a ton of pictures. I have posted a few of these pictures here.
Power Quality
26 September 2004
I'm sure glad that I live in a house with a high quality electrical system. You can ascertain the quality of our electrical system from the following log file which has been generated by our main backup power supply over the course of yesterday and today:
Sat Sep 25 02:42:04 EDT 2004 Power failure.
Sat Sep 25 02:42:07 EDT 2004 Running on UPS batteries.
Sat Sep 25 02:43:57 EDT 2004 Mains returned. No longer on UPS batteries.
Sat Sep 25 02:43:57 EDT 2004 Power is back. UPS running on mains.
Sat Sep 25 23:35:03 EDT 2004 Power failure.
Sat Sep 25 23:35:06 EDT 2004 Power is back. UPS running on mains.
Sat Sep 25 23:46:44 EDT 2004 Power failure.
Sat Sep 25 23:46:47 EDT 2004 Power is back. UPS running on mains.
Sat Sep 25 23:54:44 EDT 2004 Power failure.
Sat Sep 25 23:54:47 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:04:06 EDT 2004 Power failure.
Sun Sep 26 00:04:08 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:12:36 EDT 2004 Power failure.
Sun Sep 26 00:12:39 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:17:53 EDT 2004 Power failure.
Sun Sep 26 00:17:55 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:25:41 EDT 2004 Power failure.
Sun Sep 26 00:25:43 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:26:54 EDT 2004 Power failure.
Sun Sep 26 00:26:56 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:40:41 EDT 2004 Power failure.
Sun Sep 26 00:40:43 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:47:19 EDT 2004 Power failure.
Sun Sep 26 00:47:21 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:56:14 EDT 2004 Power failure.
Sun Sep 26 00:56:17 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 00:57:21 EDT 2004 Power failure.
Sun Sep 26 00:57:23 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:06:27 EDT 2004 Power failure.
Sun Sep 26 01:06:30 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:12:09 EDT 2004 Power failure.
Sun Sep 26 01:12:12 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:21:41 EDT 2004 Power failure.
Sun Sep 26 01:21:43 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:43:17 EDT 2004 Power failure.
Sun Sep 26 01:43:20 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:48:44 EDT 2004 Power failure.
Sun Sep 26 01:48:46 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:57:34 EDT 2004 Power failure.
Sun Sep 26 01:57:36 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 01:59:31 EDT 2004 Power failure.
Sun Sep 26 01:59:34 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:07:46 EDT 2004 Power failure.
Sun Sep 26 02:07:48 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:08:18 EDT 2004 Power failure.
Sun Sep 26 02:08:21 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:11:12 EDT 2004 Power failure.
Sun Sep 26 02:11:15 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:15:49 EDT 2004 Power failure.
Sun Sep 26 02:15:51 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:20:33 EDT 2004 Power failure.
Sun Sep 26 02:20:36 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:23:47 EDT 2004 Power failure.
Sun Sep 26 02:23:49 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:26:20 EDT 2004 Power failure.
Sun Sep 26 02:26:23 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:43:59 EDT 2004 Power failure.
Sun Sep 26 02:44:01 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 02:50:13 EDT 2004 Power failure.
Sun Sep 26 02:50:16 EDT 2004 Power is back. UPS running on mains.
Sun Sep 26 15:19:42 EDT 2004 Power failure.
Sun Sep 26 15:19:44 EDT 2004 Power is back. UPS running on mains.
Yeah.
I was reading the CIA World Factbook today, comparing various aspects of India, Peru, Ecuador and the United States, when I noticed an interesting little fact (in other words, a probable misprint). The entry for the United States claims that in the year 2001, we produced an average of 8.054 million billion barrels of oil per day and consumed an average of 19.65 million billion barrels per day. Right below these figures, it says that we neither imported nor exported any oil at all during that year. And this is the CIA! Aren't they supposed to be able to get these things right?
The Synchroscope
4 August 2004
So today, I found out how you start up, synchronize and connect a generator in a power plant with an existing power grid. There's this device called a synchroscope which measures the phase angle(s) between two different AC power systems. (I say phase angle(s) instead of angle since most power grids are three-phase. But this is not a problem, because you simply use a three-phase synchroscope in this situation.) So you just look at the synchroscope and adjust your generator until it shows up on the synchroscope as being in phase with the utility or other grid. Then you connect your generator to the grid.
I suppose that you can adjust a generator's frequency and phase angle by increasing or decreasing the strength of the magnetic field through which its coils spin. I believe that this is called the "excitation field."
The coils of wire rotated by a generator's shaft must be rotated through a pre-existing magnetic field in order to generate any electricity at all. The amount of electrical power generated is proportional to the rotational speed of the shaft and the strength of the magnetic field through which the coils are turning. The person (or machine) in charge of running the generator can easily vary the strength of the magnetic field through which the coils are turning, because this field is created by an electromagnet. This electromagnet runs off of power from a battery or from the power grid. The more power sent through the electromagnet, the harder to turn the coils on the generator shaft become. (The amount of additional power required to turn a generator's shaft increases much faster than linearly as the amount of power used to create its excitation field increases. If this were not the case, you would use up all of your extra generated power in establishing the excitation field.) When the shaft gets harder to turn, the turbine or engine driving the generator has to put more torque on the shaft (i.e. turn it harder) in order to keep it spinning at the same speed, and this mechanical energy is what the generator converts into electricity.
If more electricity needs to be generated, the steam supply to the turbine (or the fuel supply to the engine) will need to be increased, otherwise the rotational speed of the generator would decrease, causing its frequency to lag behind that of the grid and begin to pull power from the grid as if it were a big electric motor instead of a generator. If this were to actually happen, as it does from time to time in commercial power plants, protective circuitry on the generator should take the generator off of the grid and shut off the engine or turbine driving it to prevent the generator or elements of the grid from being damaged.
Incidentally, it is this type of protective circuit that caused the power grid problems that occurred in the summer of 2003 to cascade into most of the northeastern United States and southeastern Canada as they did. Had it not been for circuitry that automatically disconnects generators from the grid during adverse grid conditions, the outage would probably not have been as widespread, but it may have taken months or years to repair some of the damaged power plants, as their generators could easily have been physically destroyed (and quite possibly sent flying through the roofs of the buildings in which they were housed) if they had not been rapidly disconnected during the grid disturbance.
I research power systems from time to time, but I learned about this synchronization procedure completely by accident. I was reading peoples' reports of trips to some abandoned industrial sites on uer.ca and I happened to notice that one of the hydroelectric power plants on that site generates AC current at 25 Hz instead of 60Hz which is the standard for not only Canada, but also the United States and Mexico. I was wondering why on earth anyone would need 25Hz current these days, so I did some searching on Google, which led me to a web page created by Dr. Jim Patton at the University of Maine regarding synchroscopes, which in fact has a complete JAVA demo of the operaton of using a synchroscope to connect a generator to a power grid. I never knew just what a synchroscope was before this (although I have seen them in the control rooms of abandoned power plants), but once I saw on his website what a synchroscope does, the mystery of how the operator of a power plant connects his or her generators to the grid became pretty obvious.
I tried e-mailing Dr. Patton some follow-up questions about synchroscopes and AC power systems to his University of Maine e-mail address, but unfortunately for me, it appears that he is no longer working there and that his e-mail account there has been closed.
Despite all my rage, I am still just looking at stuff in the Powerhouse's electrical cage...
A Non-Optimal Night's Sleep
30 July 2004
So last night, Josh was going to be playing Nintendo games live on the radio during his show, which runs from three in the morning until six in the morning. This sounded like good entertainment, so I decided to head over to the studio to participate in the fun. It turned out that we didn't have the adapters with us that would have been necessary in order to connect the Nintendo to the transmitter system. It also turned out that I was an idiot when I left the house inasmuch as I forgot to take my keys with me. I remembered to bring my wallet, my cell phone, and change for the vending machine, but no keys. When the radio show finished at six o'clock, I went home planning to sleep for an hour and then to hit the snooze button for an additional half hour or so before going to work. Unfortunately, not being able to get into the house, I was unable to do that. It seemed a little selfish to wake 14 other people up just because I was dumb enough to lock myself out of the house, so I ended up snoozing on one of the couches on our porch (which the Ann Arbor City Council happens to be currently trying to ban). To make matters worse, the only alarm that I had with me was the one on my cell phone, which is not very loud. I was rather afraid that I would sleep through it and be (probably very) late for work, so I kept waking up every few minutes anyway in order to find out what time it was. All in all, it didn't really give me all the fun I expect from a night's sleep.
Our House Is Now on A Course Which Is Almost Completely Orthogonal to Destruction!
10 June 2004
That is to say that the house in which I and 14 other people now live has finally had a new fire alarm installed in it, since the old one stopped working in January, five months ago. The installation began earlier this week and was completed today. I guess the fact that another house owned by the same organization that owns my house burned to the ground a couple of weeks ago might have had something to do with this. Hooray for safety and compliance with the law!
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