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Page | 1 King Faisal University College of Engineering Department of Electrical Engineering Summer Training at Saudi Electricity Company Report By Name: Hasan Saeed Al-Qadheeb ID#: 210003380 15/08/2013

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Summer Training Report

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King Faisal University

College of Engineering

Department of Electrical Engineering

Summer Training at Saudi Electricity Company Report

By

Name: Hasan Saeed Al-Qadheeb

ID#: 210003380

15/08/2013

Page | 2

Table of Contents: Page #

1. Introduction ………………………………………………………………………….4

2. Brief History of the Company ………………………………………………………4

3. Technical and practical information gained ……………………………………….5

3-1. Power Plant (Generating Station) ………………………………………...5

3-2. Power Transmission ……………………………………………………….5

3-3. Power Distribution ………………………………………………………...6

3-4. Electricity System in SEC …………………………………………………6

3-5. Substation …………………………………………………………………..7

3-6. Ring Main Units (RMU) …………………………………………………...8

3-7. Low Voltage Panel ………………………………………………………...10

3-8. Mini Pillar …………………………………………………………………11

4. Conclusion …………………………………………………………………………...12

5. Appendix ……………………………………………………………………………..13

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List of Figures Page #

Figure 1: Power Plant ………………………………………………………………….5

Figure 2: Simple Electricity System …………………………………………………...6

Figure 3 Electricity System of SEC ……………………………………………………7

Figure 4: Substation (Transformer + RMU) ………………………………………….8

Figure 5: Example for the substation location diagram ………………………….......8

Figure 6: oil switch (RMU) ……………………………………………………………..9

Figure 7: Two types of SF6 switch (SF6 RMU) ……………………………………….9

Figure 8: Open LVP ……………………………………………………………………10

Figure 9: Mini Pillar …………………………………………………………………...11

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1. Introduction:

College of Engineering in King Faisal University gives an opportunity to

Its senior students to do summer training course in one of the industrial companies.

Summer training offer students an opportunity to get some concrete work experience and

be able to try out what it's actually like working in a particular career. So, I did my

summer training in Saudi Electricity Company (SEC). Saudi Electricity Company is a

merger of all Saudi electricity companies in the central, eastern, western and southern

regions into a single joint stock company providing generation, transmission and

distribution of safe and reliable electric services to customers in the Kingdom of Saudi

Arabia.

I spend 8 weeks working in the company from 15/06/2013 to 07/08/2013. I

worked in 4 different departments in the company as the following:

Two weeks at: Department of Testing and Identification of Faults.

Two weeks at: Department of Independent Generating Stations.

Two weeks at: Department of Operation of High Voltage (HV) Networks.

Two weeks at: Department of Emergency and Network Failures.

**See “Appendix A” for more details.

During my summer training I learned a lot of information about the company and the

electricity networks in Saudi Arabia, so in this report am going to show some important

information and details that I learned.

2. Brief History of the Company:

The first Saudi Consolidated Electricity Companies (SCECO) was (SCECO-East)

which created in 1976 (1396/1397 AH). This was followed in 1979 (1399/1400 AH) by

SCECO-South. Electricity for the southwest is provided by another consolidated

company, and the central region is served by SCECO-Central.

The General Electricity Corporation (GEC) had overall responsibility for the

Kingdom's electricity system and had direct responsibility for the provision of electrical

supplies to rural areas not then covered by the consolidated companies. The GEC

represented the government equity holdings in all the independent electricity generating

companies and was a source of finance for those companies' capital requirements.

In 1998, the Government announced the reorganization of the electricity sector by

establishing a stock market company, named the Saudi Electric Company (SEC), through

the merger of all the electricity companies operating in the Kingdom.

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3. Technical and practical information gained:

In this section in going to present some information that I learned during the

summer training period.

3-1. Power Plant (Generating Station):

A power plant is an industrial facility for the generation of electric power.

At the center of nearly all power stations is a generator, a rotating machine that

converts mechanical power into electrical power by creating relative motion

between a magnetic field and a conductor. The energy source harnessed to turn

the generator varies widely. It depends chiefly on which fuels are easily

available, cheap enough and on the types of technology that the power company

has access to. Most power stations in the world burn fossil fuels such as coal, oil,

and natural gas to generate electricity. Figure 1, shows the component of a power

plant

Figure 1: Power Plant

3-2. Power Transmission:

Here in this part the generated electricity is transfers from the Power Plant

to the main supply points throughout the eastern province by using transmission

lines which are the connecting links between the generating stations and the

distribution systems. Electricity is transmitted at high voltages (115 kV or above)

to reduce the energy lost in long-distance transmission. Power is usually

transmitted through overhead power lines. Underground power transmission has a

significantly higher cost and greater operational limitations but is sometimes used

in urban areas or sensitive locations. The power system looks like what shown in

Figure 2.

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Figure 2: Simple Electricity System.

3-3. Power Distribution:

The objective of Power Distribution System is to deliver the Electrical

power to Customers in safe, reliable and most economical way. This means that a

Customer receives a supply of Electrical power required by him at the time and

place at which he can use it. Several parameters of an Electricity supply such as

frequency, continuity of supply, voltage level, etc. should be within allowable

limits to ensure that the Customer obtains satisfactory performance for his

electrical equipment while ensuring that the demands of the Customers continue

to be met, the capital and operating costs of doing so should be reduced minimum

as possible.

3-4. Electricity System in SEC:

The power plants generate a standard voltage of 13.8 kV. Then the 13.8

kV amplified to be 230/380 kV using a step up transformer in the bulk supply

point. The 230 kV is used in the near cities whereas the 380 kV is provided if

necessary to be transmitted to far cities. This means that the 230 kV most exist in

each bulk supply point. After the transmission, the 230 kV is then converted to 69

kV using step down transformers. In the grid station, the 69 kV is converted to

13.8 kV and in turn it is transmitted to substations through Breakers. The

substation has a transformer which converts the 13.8 kV to low voltages of

220V/380V or 127V/220V. The low voltage is distributed from the low voltage

panel. Finally, the low voltage is delivered to the customer by using a mini pillar.

See Figure 3.

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Figure 3 Electricity System of SEC

3-5. Substation:

The substation is a medium voltage (MV) unit. The medium voltage is

13.8 kV coming from the grid station. This 13.8 kV is distributed to substations in which

they have step down transformers. The low voltage starts just after the transformer in the

substation. The substation uses a step down transformer that transforms the 13.8 kV to

low voltages (127 V/ 220 V). Substation is formed by the ring main unit (RMU),

transformer, and the low voltage panel. See figure 4 for example for the substation. SEC

has a complete maps and location diagram of the substations in alhasa see figure 5 as an

example. The substation name is taking the transformer name. In the next section I will

talk about the RMU.

Customer

Meter

Mini Pillar

Low Voltage Panel

Substation

13.8 kV to 127 V / 220 V

Breaker

Grid Station

69 kV to 13.8 kV

Step Down Transformer

230/380 kV to 69 kV

Bulk Supply Point

13.8 kV to 230 kV and 380 kV

Power Plant

13.8 kV

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Figure 4: Substation (Transformer + RMU)

Figure 5: Example for the substation location diagram

3-6. Ring Main Units (RMU):

The ring main unit (RMU) is a switchgear that takes the 13.8 KV cable,

links it to the transformer in the substation, and also links the 13.8 KV cable to another

substation. This means that the ring main unit has an incoming 13.8 KV cable, an

outgoing 13.8 KV cable, and a local cable. The incoming cable is a cable linked to the

substation by another substation whereas the outgoing cable is a cable linked from the

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substation to another substation. The local cable is used by the substation from the

incoming cable. There are two types of switchgears used at the company network. They

differ in the used insulation substances which are the oil switch, and the Sulfur

Hexafluoride (SF6) switch. See figure 6 for the oil switch and figure 7 for the SF6

switches.

Figure 6: oil switch (RMU)

Figure 7: Two types of SF6 switch (SF6 RMU)

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3-7. Low Voltage Panel:

The low voltage panel (LVP) is a panel that distributes the output

cables/circuits of the transformer. Each circuit from the low voltage panel contains the

red phase, yellow, and the blue phase in addition to the neutral cable which is black. The

low voltage panel output number of circuits depends on the transformer used in the

substation. The transformer output cables are connected to the bus bar of the low voltage

panel and from the bus bar, the low voltage circuits are provided such that each circuit

has a circuit breaker of 400A for each phase in the circuit. See figure 8 for opened LVP.

Figure 8: Open LVP.

3-8. Mini Pillar:

The mini pillar is a panel that takes one cable/circuit from the low voltage

panel and provides at most six circuits to divide them among at most six customers.

Figure 9 shows a mini pillar which has four connected circuits. The circuit breakers of the

mini pillars are of 200 A for each phase in a circuit. Sometimes one customer needs two

circuits from the mini pillar also when customers need higher ampere, a circuit from the

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low voltage panel is provided without using the mini pillar. There are at most two mini

pillars that can be connected together and there is two phase and one neutral cables in

each circuit, that are connected from the mini pillar to a meter because each customer

needs this specification to be energized in the low voltage.

Figure 9: Mini Pillar

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4. Conclusion:

Finally, my summer training was very interesting and very efficient. I learned a

lot of practical things that I described previously in this report. Also I apply the theorem

that I studied in the college. The employees was so friendly with me, they help me to

understand everything that I need. So I took good knowledge about power plant,

transmission lines, and substations, which are the most important sections for any electric

company.

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Appendix A: My Schedule in the company.

---------------------------------------------------------------------------------The End