Perkuliahan...dikit banget

Mau tahu berapa mata kuliah yang harus dipelajari untuk membuat seorang Master, untuk hal ini memang Indonesia jagonya, di Inggris selama setahun gak lebih dari 7 (tujuh) mata kuliah yang harus dipelajari. dari tujuh itupun ada dua atau tiga matakuliah yang dipelajari selama dua semester. Hanya saja setiap mata kuliah mempunyai bobot 15 sampai 45 kredit, buanyak banget. Hal ini berlawanan dengan program master di Indonesia yang menganut banyak mata kuliah dengan kredit sedikit-sedikit, apa itu yang membuat orang Indonesia banyak tahu dan cenderung sok tahu ya ??? dan membuat orang di Inggris kurang tahu banyak dan tidak sok tahu ?? Sebelum perkuliahan berlangsungpun, buku-buku sudah diberi tahu dan jadwal sudah disusun dengan pasti, sehingga tidak ada cerita dosen (kata orang singkatan dari "dosa kalo absen") gak tepat waktu, dan mahasiswapun sudah dapat merancang-rancang liburannya.

Puasa dan problem perjalanan

Memang benar apa kata Allah, bahwa jika kamu dalam perjalanan maka kamu dieprbolehkan untuk tidak berpuasa, kalaupun berpuasa lebih baik. Dalam perjalanan dari Cengkareng (bukan Sukarno Hatta karena singkatannya CGK bukannya SKH) diimulai jam 10 malam, sudah dengan perjuangan yang melelahkan, termasuk membawa segala macam barang-barang aneh yang tidak ada di Inggris, semacam pecel, goreng kering, belacan sampai baju batik, sampailah dengan selamat di atas kursi sempit (mungkin sebanding dengan harga tiket yang tergolong paling murah di kelasnya). Sambil terbang beberapa menu pun dihidangkan, dan terpaksa juga aku lahap, harap ini dimaklumi, bukannya karena di Indonesia gak ada makanan yang jauh lebih enak, tapi kan jarang-jarang bisa makan diatas kepala jutaan orang (di udara maksudnya). Bolak balik melihat posisi pesawat, eh seperti biasa, pesawat mampir dulu ke Singapura, padahal baru aja sejam terbang. Disini pun bukannya apa-apa cuma para penumpang dialirkan lagi ke pintu pemeriksaan yang ada di Changi, nampaknya orang luar gak percaya sama petugas bandara, sehingga harus juga di saring lagi di Singapura. Kita juga naik kepesawat itu lagi tentu dibangku yang sama dengan tetangga yang sama pula. Trus terbang lagi ke Dubai, yah kan yang punya Emirate orang Dubai, coba yang punya orang Yogya, pasti turun dulu di . Nah, turun di Dubai, kita dipersilahkan untuk melihat kekayaan yang ada di Dubai, dengan bandara yang luas dan nyaman, waktu itu jam menunjukkan pukul 9 pagi atau pukul 6 Dubai. Wah gawat juga ini, mana yang harus diikuti, puasa versi Dubai atau versi Glasgow. Kuputuskan puasa versi Glasgow, kalau jam 9.00 pagi biasanya di Glasgow masih pukul 3.00 , jadi rasanya masih sah buat sahur. Kucarilah penjual kopi dan snack, lumayan buat sahur puasa di Glasgow. Penerbangan lanjutanpun dimulai dan tiba di Glasgow pukul 2 siang dengan satu tas masih tidur di Dubai alias ketinggalan, petugas dengan sigap meminta maaf dan akan mengirimkan tasnya langsung ke Dundee. Ternyata puasa tidak sesederhana menahan lapar dan minum serta nafsu yang dapat membatalkannya.

Cheap Call Abroad From Indonesia

Bagi temen-temen yang lagi di luar negeri, hal ini mungkin dapat mengurangi kerinduan keluarga yang ada di Indonesia.

Jakarta, 1 Februari 2008 – PT. Excelcomindo Pratama Tbk. (XL) memperkuat posisinya sebagai operator yang fokus dalam menghadirkan layanan yang berkualitas dan tarif terjangkau, dengan mengeluarkan promo tarif telepon Rp 10/detik dan Rp 350/SMSuntuk menelponke 10 negara tujuan : Malaysia, Singapura, Taiwan, China, Hongkong, Korea Selatan, Australia, Amerika, India dan Inggris.Dan tarif Rp 50/detik dan Rp 499/SMS ke 41 negara lainnya. Tarif promo ini akan berlaku mulai 1 Februari – 31 Juli 2008 untuk seluruh pelanggan XL(XLbebas, XL Jempol dan XL Xplor). Direktur Marketing XL Nicanor V. Santiago mengatakan, ”Tarif baru ini merupakan salah satu wujud komitmen kami untuk memperkuat posisi kami sebagai penyedia jasa telekomunikasi yang menghadirkan tarif murah dan hemat.” Tarif promo yang ditawarkan tersebut sudah termasuk PPN, namun belum termasuk PPN untuk tarif SMS internasional bagi pelanggan XL Xplor. Cara menikmati tarif ini mudah, pelanggan cukup

tekan 01000+kode negara+nomor tujuan.

41 Negara Tujuan (di luar 10 negara) 1 Oman 12 Italia 23 Spanyol 34 Denmark 2 Qatar 13 Thailand 24 Selandia Baru 35 Portugal 3 Jordan 14 Jerman 25 Belgia 36 Kamerun 4 Kuwait 15 Jepang 26 Austria 37 Maroko 5 Syria 16 Perancis 27 Yunani 38 Afrika Selatan 6 Bahrain 17 Nigeria 28 Swiss 39 Uzbekistan 7 Brunei Darussalam 18 Pakistan 29 Kanada 40 Saudi Arabia 8 Belanda 19 Russia 30 Turki 41 Bangladesh 9 Mesir 20 Norwegia 31 Sri Lanka 10Emirat Arab 21 Vietnam 32 Hungaria 11 Filipina 22 Swedia 33 Finlandia Saat ini, selain meluncurkan tarif murah untuk berkomunikasi ke luar negeri, XL juga telah memberikan tarif murah untuk berkomunikasi ke lebih dari seratus juta nomor (sesama XL, operator lain dan PSTN) di seluruh Indonesia. Pelanggan XL Xplor dapat menikmati tarif telepon murah ke sesama XLXL (operator lain dan PSTN) Rp 23/detik di 3 menit pertama dan Rp 9/detik di menit berikutnya (tarif belum termasuk PPN 10%). Sementara penggun XL bebas dapat menikmati tarif telepon murah Rp 0,1/detik setelah 2,5 menit ke seluruh nomor, dan tarif khusus Rp 35/SMS ke sesama XL (untuk pengiriman SMS ke 11-25). Rp.9/detik di 3 menit pertama dan Rp.1/detik di menit berikutnya. Serta non Nicanor menambahkan bahwa tarif promo ini akan melengkapi berbagai manfaat yang dirasakan oleh pelangganXLberupa manfaat berkomunikasi hemat melalui jaringan berkualitas XL, yang dikenal dengan kejernihan suara dan jangkauan luasnya. Saat ini jaringan XL diperkuat oleh lebih dari 11.000 BTS (2G/3G) untuk memberikan kenyamanan berkomunikasi bagi lebih dari 15,5 juta pelanggannya di seluruh Indonesia. Tentang XL XL adalah salah satu perusahaan telekomunikasi terkemuka di Indonesia. XL beroperasi secara komersial sejak 8 Oktober 1996, dan bisnis XL saat ini terfokus ke dua sisi bisnis yaitu Consumer Solutions sebagai penyedia layanan dan jaringan berkualitas dengan harga terjangkau melalui produk-produk inovatif XL prabayar dan pascabayar, serta Business Solutions sebagai penyedia layanan solusi korporat berbasis sirkit sewa (leased line), broadband dan IP (Internet Protocol). Pada 21 September 2006, XL telah meluncurkan XL 3G, layanan telekomunikasi selular berbasis 3G pertama yang tercepat dan terluas di Indonesia.

Lewis Switches Endorsement to Obama

WASHINGTON (Feb. 27) - Civil rights leader John Lewis dropped his support for Hillary Rodham Clinton's presidential bid Wednesday in favor of Barack Obama. Lewis, a Democratic congressman from Atlanta, is the most prominent black leader to defect from Clinton's campaign in the face of near-unanimous black support for Obama in recent voting.

He also is a superdelegate who gets a vote at this summer's national convention in Denver.

In a written statement, Lewis said Obama's campaign "represents the beginning of a new movement in American political history" and that he wants "to be on the side of the people."

"After taking some time for serious reflection on this issue, I have decided that when I cast my vote as a superdelegate at the Democratic convention, it is my duty ... to express the will of the people," the statement said.

Lewis' endorsement had been a coveted prize among the Democratic candidates thanks to his standing as one of the most prominent civil rights leaders of the 1960s.

"John Lewis is an American hero and a giant of the civil rights movement, and I am deeply honored to have his support," Obama said in a statement.

Clinton, questioned about Lewis during a satellite interview with Houston television station KTRK, said: "I understand he's been under tremendous pressure. He's been my friend. He will always be my friend. At the end of the day it's not about who is supporting us, it's about what we're presenting, what our positions are, what our experiences and qualifications are and I think that voters are going to decide."

Lewis first announced his Clinton endorsement in October and has appeared on her behalf on television and at events across the country, at one point accusing Obama supporters of trying to fan the flames of race against her. Clinton has frequently cited his support in trying to establish her credentials among minority voters, saying she saw her campaign as a continuation of his work.

But Lewis came under intense pressure to get behind Obama after his constituents supported the Illinois senator roughly 3-to-1 in Georgia's Feb. 5 primary, and about 90 percent of black voters statewide voted for Obama, according to exit polls. The support among black voters nationwide to Obama's candidacy mirrors Lewis' Georgia district.

His change of heart follows a similar move by Rep. David Scott, a black Democrat who represents a neighboring district. It also comes a week after the Rev. Markel Hutchins, a young Atlanta minister, announced he would challenge Lewis in the Democratic congressional primary this summer.

Hutchins, 30, has seized on Lewis' waffling in the presidential contest as evidence that the 68-year-old congressman is out of touch.

"Today's announcement by Representative Lewis was clearly prompted by political expediency," Hutchins said Wednesday. "It is time for a change. It is time to send somebody to Congress who is actually willing to represent the district."

Earlier this month, Lewis' office disputed media reports that he said he would switch candidates, or was at least reconsidering. But until Wednesday. Lewis refused to answer questions clarifying his position.

He said Wednesday afternoon he had called former President Clinton and Sen. Clinton but had not reached them.

Lewis' announcement comes on the same day as another superdelegate, Sen. Byron Dorgan of North Dakota, endorsed Obama, citing the presidential hopeful's record on trade.

The Obama campaign also said more than 1 million people have contributed to the campaign — a threshold crossed on Wednesday. Many donors have given $25 or $50, he said. The average donation is a little more than $100.

"We have funded this campaign at the grass-roots level," campaign manager David Plouffe told reporters on a conference call. "It's really built on the backs of the American people who are getting involved in this campaign. Most of the people giving us money are also volunteering."

Dorgan said Obama has supported key trade issues. "He and I feel the same way. We both believe in trade and plenty of it. We just insist it that it be fair to our country — the rules be fair."

NAFTA, the free trade agreement with Canada and Mexico, is unpopular with blue-collar workers whose votes are critical in the Democratic primary Tuesday in Ohio.

Obama has won 11 straight primaries and caucuses since Super Tuesday, increased his advantage in the all-important delegate count and has attracted the support of his congressional colleagues. On Tuesday, he secured the endorsement of one-time presidential candidate Sen. Chris Dodd of Connecticut.

Clinton has been endorsed by 13 of her Senate colleagues, Obama 10.

Copyright 2008 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without the prior written authority of The Associated Press. All active hyperlinks have been inserted by AOL.

Duke Energy Orders 57,500 Smart Meters from Echelon

Jan 23, 2008 11:40 PM

Echelon will sell Duke Energy 57,500 advanced meters--Echelon's first U.S. utility contract. The company is one of Duke's strategic partners in the development of Duke's "Utility of the Future" and is committed to providing Duke solutions that continuously support open standards and evolving networks and technologies.

This announcement follows Echelon's Networked Energy Services (NES) overseas installation of the world's first smart metering infrastructures in Italy in the early part of this century. Today, more than 27 million meters in Italy are networked using the company's power line communications and data concentrator products. Additional NES customers include utilities around the globe in Australia, Austria, Denmark, the Netherlands, Russia and Sweden. Echelon has shipped nearly one million NES meters to utilities throughout the world. All of these meters are based on the same core networking and metering standards being used by Duke Energy.

Bloomberg News cited how smart meters cut power bills by 10 percent in a study of 112 households released Jan. 9 by the U.S. Energy Department. According to the researchers, widespread adoption of the systems would save $70 billion in costs for new power plants and lines over 20 years. Meanwhile, an analyst at ABI Research in Scottsdale, Arizona said that as many as 45 million smart meters may be ordered by 2011. In addition, he stated that the number of smart meters installed in North America rose 26 percent last year to 15.8 million. By 2013, this will surge to 61 million, according to the research firm.

THE VALUE OF POWER FACTOR TESTING

Nov 1, 2005 12:00 PM
by John Bleyer and Phillip Prout, National Grid

NATIONAL GRID DISCOVERED A HIGH POWER FACTOR DURING ACCEPTANCE TESTING of a new 40-MVA transformer in 2004. The unit was then returned to the factory for repairs, burdening both the utility and manufacturer with additional costs and delays. This article reviews the information gathered and lessons learned from this event, including testing and root-cause determination results from the teardown/repair process.

National Grid's electricity delivery companies in the United States serve 3.3 million electricity customers in New England and upstate New York through more than 1200 substations. As part of a substation expansion project, a 24/32/40-MVA, 115-kVD/13.2-kVY transformer was purchased and installed at a National Grid substation in New England.

The transformer was delivered to the substation. The radiators and bushings were installed. The unit was vacuum processed, filled under vacuum and tested by the transformer manufacturer's personnel. The following tests were performed at the substation after the unit was oil filled:

• Transformer turns ratio on all taps
• Insulation power factor of transformer and all bushings (C1 and C2)
• 10-kV excitation on all taps
• Core ground and winding resistance
• Oil quality and dissolved gas analysis (DGA).

The power factor of the high-voltage winding was elevated. The measured value of 0.58% did not meet industry-standard acceptable values or National Grid's required values. All other tests results were acceptable.

POWER FACTOR TESTING

 

Insulation power factor tests are used to measure dielectric losses, which relate the wetness, dryness or deterioration of transformer insulation. Both factory and field testing are performed to verify the insulation integrity of substation transformers. Power factor testing a two-winding transformer is conducted by energizing the winding at a known ac voltage (typically 10 kV for windings rated greater than 10 kV) with the common winding bushings shorted together.

The results of overall power factor tests on power transformers reflect the insulation condition of the windings, barriers, tap changers, bushings and oil. Modern oil-filled power transformers should have power factors of 0.5% or less, corrected to 20°C (68°F), for individual windings to ground (C_H and C_L) and interwinding insulations (C_HL). The National Grid transformer specification states that the power factor of the insulation system shall not exceed 0.5% at 20°C.

As part of the investigation into the high power factor, the transformer manufacturer retested the power factor with similar results. The high-voltage bushings were replaced and the unit was retested. The results did not change.

The unit was drained and an internal inspection was performed; nothing was found. The vendor performed a 24-hour hot oil and vacuum process to rule out the possibility of moisture in the insulation. The power factor was again retested and still had high C_H results. Both the seller and purchaser agreed that the unit should be returned to the factory for further investigation.

REVIEW OF INITIAL FACTORY TESTS PERFORMED

 

The results of the factory tests performed initially when the transformer was built were reviewed.

• Temperature rise tests were acceptable.
• Preliminary tests of resistance, polarity, phase relation, ratio, no-load loss and excitation current, impedance and load loss, excitation and power factor were all acceptable.
• Dielectric impulse, applied and induced potential tests were acceptable, following IEEE guidelines, although enhanced voltage test results were elevated.
• DGAs taken before tests and after OA and FA heat run tests were acceptable.
• DGA results after high-voltage tests indicated a problem.

Due to the gassing, the unit had been drained, reprocessed and vacuum filled. The induced voltage test and DGA tests were repeated with acceptable results. The unit was shipped.

INDUCED VOLTAGE TESTING

 

The purpose of the induced voltage test is to prove the insulation strength between parts of the same winding and insulation to ground that was not proved during the applied potential test. It also proves the condition of the insulation between windings and between phases. The voltage applied during the induced voltage testing is on the order of 1.5 to 2 times the rated voltage. Weaknesses in dielectric design, processing or manufacturing may cause partial-discharge (PD) activity during this test. PD is generally monitored on all line terminals rated 115 kV or higher during the induced voltage test. A special generator with a frequency greater than 60 Hz must be used so the core does not saturate due to the higher-than-normal voltage that is induced in the windings. For most power transformer testing, this generator is 120 Hz, 180 Hz or 240 Hz. The induced voltage test is the final dielectric test. All class II power transformers shall be induced voltage tested with the required test levels induced in the high-voltage winding. The taps shall be selected so that the test levels developed in the other windings are 1.5 times their maximum operating voltage. The voltage is raised to the one-hour level and held long enough to verify there are no PD problems. The voltage is then raised to the enhanced level and held for 7200 cycles. The voltage is then reduced to the one-hour level and held for one hour. During the one-hour period, PD measurements should be recorded at 5-minute intervals on each terminal 115 kV and above. The test is performed with the neutral terminals solidly grounded; this will stress the insulation at the same per unit of voltage.

The test frequency is increased relative to the operating frequency to avoid core saturation per IEEE standard C57.12.90.

EVALUATION OF INDUCED VOLTAGE TEST

 

Per IEEE C57.12-2000, the following criteria shall be met:

• Failure may be indicated by the presence of smoke and bubbles rising in the oil, an audible sound such as a thump or a sudden increase in test current. Any such indication should be carefully investigated by observation, by repeating the test or by other tests to determine whether a failure has occurred.
• In terms of interpretation of PD measurements, the results shall be considered acceptable and no further PD tests required under the following conditions:

  a. The magnitude of the PD level does not exceed 100 µV.

  b. The increase in PD levels during the 1-hour test does not exceed 30 µV.

  c. The PD levels during the 1-hour test do not exhibit any steadily rising trend, and no sudden, sustained increase in levels occurs during the last 20 minutes of the tests.

• Judgment should be used on the 5-minute readings so that momentary excursions of the radio-influence voltage (RIV) meter caused by cranes or other ambient sources are not recorded. Also, the test may be extended or repeated until acceptable results are obtained.
• Unless breakdown occurs or very high PDs are sustained for a long time, this test is considered as nondestructive. A failure to meet the PD acceptance criterion shall, therefore, not warrant immediate rejection, but lead to consultation between purchaser and manufacturer about further investigations.

DISSOLVED GAS ANALYSIS RESULTS

 

DGA of oil during factory testing will assist in determining if any arcing, corona discharge, low-energy sparking, overloading and overheating has occurred. The detection of gases greater than the allowable limits shall require further investigation. DGA samples should be taken before, during and after thermal performance and high-voltage tests to determine the amount of gas generated during testing. The limits listed in the table on page 58 are National Grid maximum allowable increases for gases from the beginning of any testing to the completion of all testing. Any results higher than those listed in the table would require further investigation.

BACK TO THE MANUFACTURER FOR RETESTING

 

As agreed upon by National Grid and the manufacturer, the transformer was returned to the manufacturer for inspection. The core and coils were removed from the tank, the high-voltage delta connection was broken, and single-phase winding power factor tests were performed with the unit on the drip pad.

DISCUSSION OF POWER FACTOR RESULTS

 

Treeing on the phase barrier board between H2 and H3 was found on the surface of barrier board at the base of the coils where the windings are the closest to one another.

The normal watts loss/power factor of H1 and higher watts loss/power factor on both H2 and H3 indicates the problem is common to H2 and H3 windings.

The barriers were then removed and retested, the H1 remained unchanged and the H2 and H3 watts loss/power factor lowered to the H1 values. This indicates that the contamination was related to H2-H3 barriers.

DISCUSSION OF INDUCED VOLTAGE TESTS BEFORE INITIAL SHIPMENT

 

The enhanced voltage test results indicated a normal level on H3 and higher level on H1 and H2. This appeared contradictory to what was visually found. Further analysis of the winding arrangement, location of the treeing and higher-than-expected micro-volt and pico-coulomb test results all indicated a problem at the base of #2 and #3 windings. This was because the H1 lead is connected to the bottom of the #2 winding and the H2 lead is connected to the bottom of the #3 winding stressing the bottom of the H2/H3 barrier board.

TEARDOWN, POWER FACTOR AND INDUCED VOLTAGE TESTS

 

The power factor testing during the teardown helped in identifying the location of the contamination. The winding design and location of the contamination accounted for the higher losses identified during the initial enhanced voltage test. We can assume the contamination caused arcing during the initial enhanced voltage test. The DGA results confirm that arcing occurred. The high voltage most likely burnt away the majority of the debris during the test and left a carbon tree. The subsequent oil processing and vacuum filling at the factory may have cleaned the area enough to partially cure the problem. Therefore, the second induced voltage test, prior to initial shipment, was acceptable and the DGA showed no arcing at that time.

LABORATORY ANALYSIS OF BARRIER BOARD

 

The transformer H2/H3 barrier pressboard was removed from the unit and brought to the Doble Materials Laboratory in Watertown, Massachusetts, U.S., for analysis. An initial visual examination of the pressboard showed that discharge treeing was quite distinct. An adjacent board was also inspected and there was no discharge treeing visible. The Doble Materials Laboratory was asked to aid in determining the cause of the discharge treeing in the pressboard. Unfortunately, the pressboards were not stored in a controlled environment at the transformer manufacturer after they were removed from the transformer, thus making it impossible to determine if moisture and metal particle contamination were present on the barrier board when the transformer was assembled.

FACTORY REPAIR

 

The top yoke was removed and the coils were un-nested. A complete visual inspection of the coils was performed. The barrier insulation, top and bottom insulation, and leads were replaced. The unit was reassembled and fully re-tested. All factory test results after the repair were acceptable and the unit was shipped. The unit was delivered to the substation, dressed, vacuum filled and tested by the vendor. All field test results were acceptable.

LESSONS LEARNED

 

• It is important to set power factor limit for acceptance testing.
• It is important to set DGA limits for factory testing.
• Require reporting of all factory test results in the final test report.
• Factory power factor testing should be performed before and after thermal/high-voltage tests.
• Specification should include limits for the induced voltage test during the enhanced voltage period.
• Specifications should include a statement similar to: "If the transformer fails any test, the purchaser shall be notified immediately. The purchaser shall be consulted about the failure, and based on the test results, the purchaser may require a complete retest of all tests."
• Preservation of removed parts in controlled environments is essential when performing root-cause analysis.

In conclusion, there is great value in analyzing all test results, as each test represents a different component that verifies the design and manufacturing process. All test results should be reviewed prior to releasing a transformer for shipment. National Grid believes there is value in performing a power factor test before and after factory testing. In this case, induced voltage testing was acceptable but power factor testing revealed a problem. Final power factor test results also will assist the purchaser when performing field acceptance testing. The manufacturer who supplied this transformer now performs power factor tests before and after high-voltage testing.

John Bleyer is a senior substation equipment maintenance engineer at National Grid. He graduated from Worcester Polytechnic Institute in 1986 with a BSEE degree. Bleyer provides technical support to substation field operations personnel in the New England area. He has more than 15 years of experience in substation maintenance and design. JOHN.BLEYER@us.ngrid.com

Phillip Prout is lead senior maintenance engineer at National Grid in the Substation O&M Services group located in Massachusetts. He is a 1986 graduate of Wentworth Institute of Technology from the mechanical engineering program. He has 15 years of field experience, including 10 years as a substation supervisor. He is currently the chairperson on the Doble Insulating Materials Committee. PHILLIP.PROUT@us.ngrid.com

Insulation Tested	% Power Factor Corrected to 20°C
CH	0.58
CL	0.21
CHL(UST)	0.15
Oil	0.02
Power factor acceptance test.

 

Insulation Tested	% Power Factor Corrected to 20°C
CH	0.21
CL	0.18
CHL(UST)	0.14
Initial factory power factor testing prior to high-voltage testing.

 

Kv P-P	% of Enhancement	Time (min)	H1		H2		H3
			pC	uV	pC	uV	pC	uV
0	0		0	9	0	12	0	11
52	25		0	9	0	12	0	11
104	50		5	9	5	12	0	11
156	75		19	13	20	17	0	11
208	100		478	250	581	700	34	35
182	87.5	0-60	5-20	16-50	0-8	23-40	0-5	20-35
Factory-induced voltage testing dated April 26, 2004, prior to shipment. (Enhanced 120L-G/208P-P — One Hour 105L-G/182P-P)

 

Date	4/24/04	4/25/04	4/26/04	4/26/04	Test Limits
Note	Before all tests	After OA Heat Run	After FA Heat Run	After all Tests
Hydrogen	1	8	8	16	10
Methane	0	0	0	0	5
Ethane	0	0	0	0	2
Ethylene	0	0	0	1	2
Acetylene	0	0	0	5	0
Carbon Monoxide	4	20	48	67	30
Carbon Dioxide	25	62	149	153	300
Initial factory DGA test results.

 

Gas name	Gas symbol	ppm limit
Hydrogen	H2	10
Methane	CH4	5
Ethane	C2H6	2
Ethylene	C2H4	2
Acetylene	C2H2	0
Carbon Monoxide	CO	30
Carbon Dioxide	CO2	300
National Grid maximum gas limits.

 

Test #	Insulation	Test Connection			Mode	kV	% PF	Cap.
		Energize	Ground	Guard
1	CH1	H1	-	LV, H2, H3	GST	2.5	0.44	267.39
2	CH2	H2	-	LV, H1, H3	GST	2.5	1.95	227.30
3	CH3	H3	-	LV, H1, H2	GST	2.5	1.92	237.29
Power factor (PF) testing of transformer (115kV delta connection cut — on drip pad).

 

Test #	Insulation	Test Connection			Mode	kV	mA	Watts	% PF	Cap.
		Energize	Ground	Guard
4	CH1	H1	-	LV, H2, H3	GST	2.5	0.253	2.4	0.39	268.79
5	CH2	H2	-	LV, H1, H3	GST	2.5	0.212	2.4	0.45	220.90
6	CH3	H3	-	LV, H1, H2	GST	2.5	0.219	2.0	0.35	230.26

Executive: Regulatory Obstacles to Smart Grids Prevent Reliable Power

Feb 25, 2008 1:40 PM
Galvin Electricity Initiative

To meet future power demand and provide quality, reliable electricity to American homes and businesses, policymakers and state regulators need to change the way electric power utilities do business now, Kurt Yeager, executive director of the Galvin Electricity Initiative, said last week.

Speaking before an audience of federal and state regulators, utilities and other industry players as part of a keynote panel during the National Electricity Delivery Forum in Washington, D.C., Yeager said that the future of the U.S. electric power system rests on our ability to take advantage of the technology available today and prioritizing the modernization of our unreliable, inefficient and insecure grid infrastructure.

"Our electric power system has been in a subprime mortgage-like era for decades," Yeager said. "There are no technological or economical obstacles to modernizing the U.S. electric grid, only policy and regulatory barriers that must be eliminated," said Yeager. "If states open up the electricity market and offer utilities incentives for integrating smart grid technology and giving consumers control of their own energy use, everyone will win. Consumers gain better service and a smaller carbon footprint while utilities gain much-needed upgrades and a system that is less vulnerable to cyber-attack."

During the panel discussion, Yeager shared some of the Initiative's key proposals that will pave the way for a more intelligent electricity grid:

The technology exists today to transform the 1950s-era grid into a smarter, reliable and efficient power system. To secure this future, state leadership is needed to remove the regulatory policy obstacles to smart grid development and implementation.

Utilities need incentives to drive grid modernization efforts. Utilities are compensated for selling more electricity, not for providing quality service or efficiency programs. States need to support "decoupling," or separating utilities' profits from their energy sales. Only then will utilities become motivated to offer consumers tools such as time-of-use pricing and smart meters that can reduce the escalating demand that is taxing our aging grid infrastructure, increasing emissions of dangerous pollutants. Consumers should be treated as individuals with individual needs. As with other industries that have been opened to competition and choice, given the option, most consumers will take control and reduce their energy use.

Renewable resources are an important part of our electricity generation mix, but they will not eliminate coal-generated or nuclear power. States should examine their available renewable resources for electricity generation -- solar, wind, geothermal, biomass, etc. -- and add them to their electricity generation portfolio. While the industry is addressing their greenhouse gas, waste and security issues, in order to meet our huge demand for electricity economically, coal and nuclear sources of electricity will remain the primary part of the generation mix. Carbon capture and sequestration has promise for yielding cleaner electricity from coal, but as a long-term goal, not a short-term solution. Since the volume of CO2 emitted by coal-fired plants that could be captured equals the amount of oil that is consumed in the United States yearly, finding a practical way to transport and store it is a complicated undertaking which is not receiving enough attention.

New transmission lines should be the last option. Technology currently exists to increase the capacity of the wires we have today. With the addition of "smart" electronic controls, transmission lines can run closer to their limits without risking overload. This will also minimize the major security and vulnerability risks that these extensive transmission networks pose to the nation today.

The National Electricity Delivery Forum is the preeminent national forum that examines and addresses the inherent infrastructure challenges and issues that impact electricity delivery. Sponsored annually by the National Association of Regulatory Utilities Commission (NARUC) and the U.S. Department of Energy Office of Electricity Delivery and Energy Reliability (DOE), this forum addressed the role of U.S. electric power delivery in addressing the challenges of climate change, demand growth and energy security.

Transmission Line Conductor Design Comes of Age

Jun 1, 2003 12:00 PM
By Art J. Peterson Jr. and Sven Hoffmann, National Grid

Deregulation and competition have changed power flows across transmission networks significantly. Meanwhile, demand for electricity continues to grow, as do the increasing challenges of building new transmission circuits. As a result, utilities need innovative ways to increase circuit capacities to reduce congestion and maintain reliability.

National Grid is monitoring transmission conductor technologies with the intent of testing and deploying innovative conductor technologies within the United States over the next few years. In the UK, National Grid has been using conductor replacement as a means of increasing circuit capacity since the mid 1980s, most recently involving the high-temperature, low-sag "Gap-type" conductor. As a first step in developing a global conductor deployment strategy, National Grid embarked on an overall assessment of overhead transmission line conductor technologies, examining innovative and emerging technologies.

Conventional Conductors

 

The reality is that there is no single "wonder material." As such, the vast majority of overhead line conductors are nonhomogeneous (made up of more than one material). Typically, this involves a high-strength core material surrounded by a high-conductivity material. The most common conductor type is the aluminum conductor steel reinforced (ACSR), which has been in use for more than 80 years. By varying the relative cross-sectional areas of steel and aluminum, the conductor can be made stronger at the expense of conductivity (for areas with high ice loads, for example), or it can be made more conductive at the expense of strength where it's not required.

More recently, in the last 15 to 20 years, the homogeneous all-aluminum alloy conductor (AAAC) has become quite popular, especially for National Grid in the UK where it is now the standard conductor type employed for new and refurbished lines. Conductors made up of this alloy (a heat treatable aluminum-magnesium-silicon alloy) are, for the same diameter as an ACSR, stronger, lighter and more conductive, although they are a little more expensive and have a higher expansion coefficient. However, their high strength-to-weight ratio allows them to be strung to much lower initial sags, which allows higher operating temperatures. The resulting tension levels are relatively high, which could result in increased vibration and early fatigue of the conductors. In the UK, with favorable terrain, wind conditions and dampers, these tensions are acceptable and have allowed National Grid to increase the capacities of some lines by up to 50%.

For the purpose of this article, the three materials mentioned so far — steel, aluminum and aluminum alloy — are considered to be the materials from which conventional conductors are made. The ACSR and AAAC are two examples of such conductors. Other combinations available include aluminum conductor alloy reinforced (ACAR), aluminum alloy conductor steel reinforced (AACSR) and the less common all-aluminum conductor (AAC).

Conductors of these materials also are available in other forms, such as compacted conductors, where the strands are shaped so as not to leave any voids within the conductor's cross section (a standard conductor uses round strands), increasing the amount of conducting material without increasing the diameter. These conductors are designated trapezoidal-wire (TW) or, for example, ACSR/TW and AACSR/TW. Other shaped conductors are available that have noncircular cross sections designed to minimize the effects of wind-induced motions and vibrations.

High-Temperature Conductors

 

Research in Japan in the 1960s produced a series of aluminum-zirconium alloys that resisted the annealing effects of high temperatures. These alloys can retain their strength at temperatures up to 230°C (446°F). The most common of these alloys — TAl, ZTAl and XTAl — are the basis of a variety of high-temperature conductors.

The thermal expansion coefficients of all the conventional steel-cored conductors are governed by both materials together, resulting in a value between that of the steel and that of the aluminum. This behavior relies on the fact that both components are carrying mechanical stress.

However, because the expansion coefficient of aluminum is twice that of steel, stress will be increasingly transferred to the steel core as the conductor's temperature rises. Eventually the core bears all the stress in the conductor. From this point on, the conductor as a whole essentially takes on the expansion coefficient of the core. For a typical 54/7 ACSR (54 aluminum strands, 7 steel) this transition point (also known as the "knee-point") occurs around 100°C (212°F).

For lines built to accommodate relatively large sags, the T-aluminum conductor, steel reinforced (TACSR) conductor was developed. (This is essentially identical to ACSR but uses the heat-resistant aluminum alloy designated TAl). Because this conductor can be used at high temperatures with no strength loss, advantage can be taken of the low-sag behavior above the knee-point.

If a conductor could be designed with a core that exhibited a lower expansion coefficient than steel, or that exhibited a lower knee-point temperature, more advantage could be taken of the high-temperature alloys. A conductor that exhibits both of these properties uses Invar, an alloy of iron and nickel. Invar has an expansion coefficient about one-third of steel (2.8 microstrain per Kelvin up to 100°C, and 3.6 over 100°C, as opposed to 11.5 for steel). T-aluminum conductor Invar reinforced (TACIR) is capable of operation up to 150°C (302°F), with ZTACIR and XTACIR capable of 210°C (410°F) and 230°C (446°F), respectively.

Further, the transition temperature, although dependent on many factors, is typically lower than that for an ACSR, allowing use of the high temperatures within lower sag limits than required for the TACSR conductors. One disadvantage of this conductor is that Invar is considerably weaker than steel. Therefore, for high-strength applications (to resist ice loading, for example), the core needs to make up a greater proportion of the conductor's area, reducing or even negating the high-temperature benefits. As a result, the ACIR-type conductors are used in favorable areas in Japan and Asia, but are not commonly used in the United States or Europe.

There will still be instances, however, where insufficient clearance is available to take full advantage of the transitional behavior of the ACIR conductors. A conductor more suitable for uprating purposes would exhibit a knee-point at much lower temperatures. Two conductors are available that exhibit this behavior: the Gap-type conductor and a variant of the ACSR that uses fully annealed aluminum.

Developed in Japan during the 1970s, Gap-type ZT-aluminum conductor steel reinforced (GZTACSR) uses heat-resistant aluminum over a steel core. It has been used in Japan, Saudi Arabia and Malaysia, and is being extensively implemented by National Grid in the UK. The principle of the Gap-type conductor is that it can be tensioned on the steel core alone during erection. A small annular Gap exists between a high-strength steel core and the first layer of trapezoidal-shaped aluminum strands, which allows this to be achieved. The result is a conductor with a knee-point at the erection temperature. Above this, thermal expansion is that of steel (11.5 microstrain per Kelvin), while below it is that of a comparable ACSR (approximately 18). This construction allows for low-sag properties above the erection temperature and good strength below it as the aluminum alloy can take up significant load.

For example, the application of GZTACSR by National Grid in the UK allowed a 90°C (194°F) rated 570 mm2 AAAC to be replaced with a 620 mm2 GZTACSR (Matthew). The Gap-type conductor, being of compacted construction, actually had a smaller diameter than the AAAC, despite having a larger nominal area. The low-sag properties allowed a rated temperature of 170°C (338°F) and gave a 30% increase in rating for the same sag.

The principal drawback of the Gap-type conductor is its complex installation procedure, which requires destranding the aluminum alloy to properly install on the joints. There is also the need for "semi-strain" assemblies for long line sections (typically every five spans). Experience in the UK has shown that a Gap-type conductor requires about 25% more time to install than an ACSR.

A semi-strain assembly is, in essence, a pair of back-to-back compression anchors at the bottom of a suspension insulator set. It is needed to avoid potential problems caused by the friction that developes between the steel core and the aluminum layers when using running blocks. This helps to prevent the steel core from hanging up within the conductor.

During 1999 and 2000, in the UK, National Grid installed 8 km (single circuit) of Matthew GZTACSR. Later this year and continuing through to next year, National Grid will be refurbishing a 60 km (37-mile) double-circuit (120 circuit-km) route in the UK with Matthew.

Westar Energy Publishes Comprehensive Energy Plan

Feb 25, 2008 2:03 PM
Westar Energy, Inc.

Westar Energy, Inc., Topeka, Kansas, has published a comprehensive energy plan that outlines the company's plans to meet growing customer needs while operating in rapidly changing financial, environmental and political climates.

The plan is entitled "Meeting Our Customers' Energy Needs: A Strategic Plan for Uncertain Times." As outlined in the plan, Westar's strategy embraces state and federal policies encouraging greater reliance on energy efficiency and the development of more transmission and renewable energy sources. It also calls for deferring as long as possible constructing a new conventional coal plant, but maintaining existing coal plants and making substantial investments in them to improve their environmental performance. During this period of deferral, Westar will be vigilant regarding the development and costs of emerging generation technologies that are not yet commercially feasible. The strategy also would extend the operating life of existing nuclear generation.

"We are staying true to our mission as an electric-only utility with this strategy," said Bill Moore, Westar president and CEO. "We recognize and respect that there will be differences as to how best we should proceed. Nevertheless, we offer our plan as an invitation to engage in a constructive discussion with policy-makers and interested customers on the challenges we face together. It is intended to be an open, transparent disclosure of how we see our future. We hope it will be viewed as a useful contribution to broader policy forums where energy and environmental issues are considered and thoughtfully discussed."

Warga Sibolga Protes Pembangunan Menara SUTET

27/02/2008 00:12 SUTET
Liputan6.com, Sibolga: Pembangunan tower jaringan listrik tegangan tinggi atau SUTET kembali menuai protes. Kali ini terjadi di Sibolga, Sumatra Utara, Selasa (26/2). Warga menuntut SUTET di kawasan mereka segera dipindahkan karena dinilai mengganggu keselamatan warga sekitar.

Warga yang memprotes pembangunan menara SUTET berunjuk rasa ke Kantor DPRD Sumut. Mereka meminta SUTE segera dirobohkan atau dipindahkan. Jika tuntutan tidak dipenuhi, warga berencana merubuhkan SUTET sendiri.

Wakil Ketua DPRD Sibolga Yusran Tanjung berjanji memanggil Pemerintah Kotamadya dan PLN untuk memindahkan tower SUTET. Namun warga belum puas. Mereka melanjutkan aksi ke Kantor Walikota Sibolga karena diduga pembangunan SUTET belum ada izin Pemkot Sibolga.(JUM/Chaerul Dharma dan Cuk Arbianto)