IEEE Power & Energy Magazine - September/October 2019 - 83

Arc
Lights

Incandescent
Lights

1881

6,000

5,000

1886

140,000

550,000

1902

390,000

18,000,000

Lighting," which was issued 22 March
1881 as U.S. patent number 239,147.
This invention relates to a system
of laying the conductors conveying the current from a central station or source of electric energy
throughout a system of electric
lighting or translation.
This is the first time the railway term
"central station" was adopted to designate an electric-power central station.
Edison's short-lived Holborn Viaduct
central station in London began operating on 24 April 1882 with a capacity of
2,200 16-candlepower lights. The famous
Pearl Street station and distribution system of the Edison Electric Illuminating
Co. of New York in lower Manhattan
began operation on 4 September 1882.
Within a month, the company had 59
customers with 1,284 lights, and on 1 December 1883, 513 customers with 10,297
lights, according to a bulletin of the Edison Electric Light Company. (This was
Edison's first electric company, incorporated in New York on 15 November
1878. It funded Edison's electric light
experiments and controlled his patents.)
In 1887, Edison had 103 dc central stations in the United States, with 311,400
lights in use.

The ac System of Lucien
Gaulard and John Dixon Gibbs
Practical transformers for the downconversion of high-voltage dc power
did not exist in the 19th century. In the
United States and many other countries,
high-voltage, long-distance transmission
began with ac systems, for which practical down-conversion transformers were
developed. However, an early high-voltage dc transmission system, invented by
Swiss engineer René Thury, competed
september/october 2019

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Data

Component
Type
Bus
Bus
Bus
Bus

100

0.08

90

80

0.07

70
0.06

PANEL

PANEL

0.09

60
0.05
50
0.04
40
0.03

Cumulative Percent

Year

On 18 April 1883, The Times of London published a detailed description of
the first system of ac power distribution.
An important advance in electrical
science, as regards the distribution
of the electrical current, has been
affected by Messrs. Gaulard and

with ac systems in some European countries for more than 30 years, starting in
1889. In the absence of dc down-converting transformers, this system used
dc dynamos in series at the generating
station and dc motors in series at the receiving stations as voltage dividers.

Unavailability (hrs/year)

table 1. The number of arc lights
and incandescent electric lights
in the United States (1881-1902).

30

Name

Failure
Contirbution (%)

Failure Rate
(per year)

Avg Repair
Time (hrs)

Unavailability
(hrs/year)

Uptime (%)

0.02

MAIN BUS A
MAIN BUS B
MECH BUS A
MECH BUS B

12.4003
12.4003
12.4001
12.4001

0.00949048
0.00949048
0.009490247
0.009490247

7.289839
7.289839
7.2899071
7.2899071

0.06918407
0.06918407
0.069183016
0.069183016

0.9999921
0.9999921
0.9999921
0.9999921

0.01

Breaker
Branch
Branch
Breaker
Breaker
Breaker
Breaker
Branch
Branch
Breaker
Breaker

BL-7
C-1_A
C-1_B
BL-6
BL-6_A
BL-17
BL-17_A
C-1_C
C-1
BL-10
BL-10_A

5.76386
5.30718
5.30718
4.12983
4.12983
2.70288
2.70288
2.65359
2.12287
1.35144
1.35144

0.00085777
0.00282
0.00282
0.002400276
0.002400276
0.0026
0.0026
0.00141
0.001128
0.0013
0.0013

37.490168
10.5
10.5
9.599442
9.599442
5.8
5.8
10.5
10.5
5.8
5.8

0.032157953
0.02961
0.02961
0.023041312
0.023041312
0.01508
0.01508
0.014805
0.011844
0.00754
0.00754

0.99999633
0.99999662
0.99999662
0.99999737
0.99999737
0.99999828
0.99999828
0.99999831
0.99999865
0.99999914
0.99999914

Breaker
Breaker
Breaker
Breaker
Breaker
Breaker
Breaker
Breaker
Breaker
Breaker
Breaker

Breaker

BL-8
BL-8_A
BL-9
BL-9_A
BL-14
BL-14_A
BL-15
BL-15_A
BL-7_A
BL-16
BL-16_A

1.35144
1.35144
1.35144
1.35144
0.991175
0.991175
0.991175
0.991175
0.991175
0.496484
0.496484

0.0013
0.0013
0.0013
0.0013
0.002765
0.002765
0.002765
0.002765
0.002765
0.001385
0.001385

5.8
5.8
5.8
5.8
2
2
2
2
2
2
2

0.00754
0.00754
0.00754
0.00754
0.00553
0.00553
0.00553
0.00553
0.00553
0.00277
0.00277

0.99999914
0.99999914
0.99999914
0.99999914
0.99999937
0.99999937
0.99999937
0.99999937
0.99999937
0.99999968
0.99999968

Breaker
Breaker
Breaker
Breaker

BL-16_B
BL-16_C
BL-2
BL-2_A

0.496484
0.496484
0.0833447
0.0833447

0.001385
0.001385
0.00093
0.00093

2
2
0.5
0.5

0.00277
0.00277
0.000465
0.000465

0.99999968
0.99999968
0.99999995
0.99999995

20

10

0.00

M

ain

Bu

s

Bu

s2

Bu

s3
B

S
us

W

BL

-1

1
C_

-A

1
C_

-B

BL

-6

BL

-4

0

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