PSA- Laboratory 3 Luansing-merged PDF

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Republic of the PhilippinesBATANGAS STATE UNIVERSITYGPB Main II, Alangilan, Batangas CityCollege of Engineering, Architecture and Fine ArtsLaboratory Experiment No. 3Device Duty Check of the Protective DevicesEE 410- Power System AnalysisSubmitted by:Luansing, Angelica Nicole D.Submitted to:Engr. Ma...

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Republic of the Philippines BATANGAS STATE UNIVERSITY GPB Main II, Alangilan, Batangas City College of Engineering, Architecture and Fine Arts

Laboratory Experiment No. 3 Device Duty Check of the Protective Devices EE 410- Power System Analysis

Submitted by: Luansing, Angelica Nicole D.

Submitted to: Engr. Marjorie Marcaida Instructor

May 29, 2021

Laboratory Experiment No. 3 Device Duty Check of the Protective Devices

Introduction The Power System Network included laboratory number two is composed of 13.2 kV and 350 short circuit MVA incoming supply having a 60 Hz frequency which is the frequency generally used in the Philippines. It serves a local distribution network consisting of two power transformers. The transformers serve the feeder loads consisting of three-phase and single-phase loads and it is connected to a tie-breaker for contingency purposes. Under normal operation, the breaker is normally open. Moreover, the standby generator is connected to the transformer 2 feeder bus to be used for contingency situations. The IEC 60909 standard categorizes short-circuit currents by magnitude (maximum and minimum) and fault distances from generators, which ETAP Short Circuit Analysis follows. Protective device settings are based on minimum currents, while equipment ratings are based on maximum short-circuit currents. To calculate the magnitude of short circuit current that the system is capable of producing and to compare that magnitude to the overcurrent protective devices' interrupting rating, a short circuit analysis is performed (OCPD). One of the most significant protection devices is a circuit breaker, which is a current interruption (switching) device. If necessary, the circuit breaker can be manually actuated, but it is also designed to 'trip' automatically in the event of an overload or other type of system fault. It detects the problem and activates a protection relay before any damage is done. It helps to keep electrical appliances and devices safe. It disables the overloaded circuit while allowing current to flow via the unaffected circuits. It also isolates the system's circuitry and powered components. This safeguards the person who is repairing the electrical system or equipment.

Objectives After performing this simulation, the students should be able to: 1. Be familiar with Power System components and their representation in ETAP 2. Develop the power system network model through ETAP. 3. Simulate the network model and evaluate the system performance with different system configurations/scenarios. 4. Implement appropriate solutions to fix system problems

Materials ● ETAP Software ● Philippine Electrical Code 2017 ● Power System Network from Laboratory No. 1

Circuit Diagram Figure 1 below shows the power system network to be simulated using ETAP software. The specifications are chosen based on the appropriate values for the system network.

Figure 1. Power System Network

Procedure 1.

Pre-Lab Information A 2-hour pre-lab ETAP session will be conducted to explain the principles of equipment sizing, feeder sizing, protective device rating, and other relevant system settings. Building the entire network with complete system specification will also be part of the pre-lab sessions.

2. Power System Network As shown in Figure 1, an incoming 13.2kV, 3ϕ, 60 Hz, power supply with a short circuit MVA of 350 MVA serves a local distribution network consisting of two power transformers. Each transformer serves each respective feeder loads that consist of either 3- phase and 1-phase loads as indicated in Figure 1. A tier breaker connects the two transformers for some contingency situations. The breaker is normally open during normal operation. Also, a standby generator is connected to the 0.220 kV feeder bus that can use during contingency situations. 3.

System Specification Specify the rating of all system components based on Figure 1, using ETAP supplied specification data from various suppliers. Specification of system components should be based on actual loading condition plus some kind of safety factor as necessary.

4.

Power System Performance Evaluation 4.1. Printout the ETAP-built network showing component details that indicates input values from given components specifications. Use A4 size paper. 4.2. In the system configuration shown in Figure 1, specify the circuit breakers rating, Rating of circuit breakers include two most important rating - continuous current rating and interrupting rating. 4.3. With all circuit breakers closed, perform device duty check. If alerts exist, fix them. 4.4. Repeat item 4.3 for the scenarios created in lab sheet no. 2 4.5. Show all relevant activities and results of your analysis.

Results and Discussion This part will discuss how the data were collected and the results of the laboratory experiment simulated through ETAP software. The simulation results using ETAP software are shown below after conducting the procedures. The specifications of the various components that make up the device network are detailed in order to effectively run the simulation under various scenarios. The power system network was operated normally, with Gen 1 down and all loads active. Different issues with voltages and other components have been identified, and solutions have been proposed to address these issues. The ratings and sizes of the components are chosen according to the manual computation, Philippine Electrical Code 2017, and availability in the software. Figure 2 presents the power system network built through ETAP with complete ratings and specifications.

Figure 2. Power System Network Figure 2 shows the circuit diagram of the given Power System Network built in ETAP software. It has an incoming supply of 13.2 kV, three-phase, 60 Hz with 350 short circuit MVA that serves a local distribution network consisting of two power transformers serving three-phase and single-phase feeder loads. For contingency situations, a tier-breaker is connected to the two transformers and a standby generator is connected to the 0.240 kV feeder bus

The following tables show the specifications, ratings, and sizes of the components of the power system network. Table 1 presents the specifications of the incoming supply and the standby generator. The rating of the supply components is based on Figure 1 and the specification data provided from various suppliers in ETAP. Table 1. Supply Supply

Bus No.

Specifications

Incoming Supply

Bus 1

13.2 kV Swing Configuration 350 MVASC X/R = 40 Y-grounded

Standby Gen 1

T2 Feeder Bus

0.240 kV 3429 kW 3-phase PF = 85% EFF = 95%

The incoming supply has 13.2 kV, Swing configuration, and 350 short circuit MVA rating. Also, it is Y-grounded and has an X/R ratio of 40. The incoming supply is connected to Bus 2. The standby generator is rated based on manual computation and the data provided by ETAP suppliers. It is a three-phase generator having a power factor of 85 % and an efficiency of 95 %. It supplies 1000 kW to the T2 Feeder Bus.

Table 2 shows the specifications of the transformers of the local distribution network which supplies the respective feeder loads indicated in figure 2. Table 2. Transformer ID MVA Name

Rated Voltage (kV)

FLA (A)

%Z

X/R

Grounding Bus No.

T1

3

13.2/0.24

131.2/7217

5.75

10.67

D-Y

Bus 1/T1 Feeder Bus

T2

3

13.2/0.24

131.2/7217

5.75

10.67

D-Y

Bus 1/T2 Feeder Bus

Table 2 presents the specifications of the transformers. Both primary sides are connected to Bus 1 while the T1 Secondary is connected to the T1 Feeder bus and the T2 Secondary is connected to T2 Feeder Bus. The 13.2 kV is stepped down to 0.24 kV. Each

transformer has a full load current of 131.2 A (primary side) and 7217 A (secondary side). The percent impedance, X/R ratio, and grounding are provided by the ETAP suppliers. Table 3 shows the specifications of the cable including the configuration, manufacturer, insulation that supports the power system network. Table 3. Cable ID Name

Length (m)

T1 Cable

Size kV (AWG)

Manufacturer KIRETE

Insulation

Bus No.

EPR

Bus 1

4/0

15

4/0

15

KIRETE

EPR

Bus 1

Gen. Cable

4/0

15

KIRETE

EPR

T2 Feeder Bus

Chiller Cable 1

4/0

0.6

NEC

THHN

T1 Feeder Bus

Chiller Cable 2

4/0

0.6

NEC

THHN

T1 Feeder Bus

Feeder Cable 1

4/0

0.6

NEC

THHN

T2 Feeder Bus

4/0

0.6

NEC

THHN

T2 Feeder Bus

Feeder Cable 3

4/0

0.6

NEC

THHN

T2 Feeder Bus

Feeder Cable 4

4/0

0.6

NEC

THHN

T2 Feeder Bus

4/0

0.6

NEC

THHN

T2 Feeder Bus

T2 Cable

20

50

Feeder Cable 2

75

150 Feeder Cable 5

Feeder Cable 6

4/0

0.6

NEC

THHN

Bus_2

Feeder Cable 7

4/0

0.6

NEC

THHN

Bus_2

Feeder Cable 8

4/0

0.6

NEC

THHN

Bus_2

4/0

0.6

NEC

THHN

Bus_2

4/0

0.6

NEC

THHN

Bus_2

Feeder Cable 11

4/0

0.6

NEC

THHN

Bus_3

Feeder Cable 12

4/0

0.6

NEC

THHN

Bus_3

Feeder Cable 13

4/0

0.6

NEC

THHN

Bus_3

Feeder Cable 9 Feeder Cable 10

25

The cables presented in Table 3 were selected from NEC and KIRETE manufacturers having insulation of EPR and THHN. Ethylene Propylene Rubber (EPR) is resistant to heat, oxidation, ozone, and different weather conditions. THHN cables can also withstand dry and damp locations because of their flame-retardant, heat-resistant thermoplastic insulation. The size of the cables is chosen based on their full load ampacity and the necessary demand factor of each component.

Table 4 below shows the necessary specifications of the circuit breakers used in this laboratory experiment. Table 4. Circuit Breaker ID Name

MFR Model

& Max. kV

Tie-Breaker

Hyundai HAT50

B1

ITE-Gould 15-HK-750

Continuous Rated Amp (A trip) Interrupting Current (kA)

Bus No.

0.69

20 000

250

T1 Feeder Bus to T2 Feeder Bus

15

2000

28.9

Bus 1

B2

ITE-Gould 15 15-VHK-100 0

1000

37

Bus 1

B3

ITE-Gould 15 15-VHK-100 0

1000

37

Bus 1

B4

Hyundai HAT50

0.24

10 000

250

T1 Bus

Feeder

B5

Hyundai HAT50

0.24

10 000

250

T2 Bus

Feeder

B6

Hyundai HAT50

0.24

10 000

250

T2 Bus

Feeder

CB_1

Hyundai HAT50

0.24

8000

100

T1 Bus

Feeder

CB_2

Hyundai HAT50

0.24

800

100

T1 Bus

Feeder

CB_3

General Electric THKM12

0.24

700

65

T2 Bus

Feeder

CB_4

Hyundai HAT20

0.24

1200

65

T2 Bus

Feeder

CB_5

Hyundai HAT20

0.24

1200

65

T2 Bus

Feeder

CB_6

Hyundai HAT20

0.24

1500

50

T2 Bus

Feeder

CB_7

Hyundai HAT20

0.24

1100

50

T2 Bus

Feeder

CB_8

General Electric THJK6

0.24

300

65

Bus_2

CB_9

General Electric THJK6

0.24

400

35

Bus_2

CB_10

General Electric

0.24

200

35

Bus_2

THJK4 CB_11

General Electric THJK6

0.24

250

35

Bus_2

CB_12

General Electric THJK6

0.24

300

35

Bus_2

CB_13

General Electric THJK6

0.24

400

35

Bus_3

CB_14

General Electric THJK6

0.24

400

35

Bus_3

CB_15

General Electric THJK6

0.24

300

65

Bus_3

The circuit breakers are chosen based on their availability in ETAP and the results of the manual computation. The continuous ampacity is computed by the full-load ampacity plus the demand factor of the components connected to the circuit breakers. B1-B5 are high-voltage circuit breakers connected at the local distribution network consisting of two power transformers. The low-voltage circuit breakers, CB1-CB15, are connected to the secondary side of the power transformers wherein the voltage is stepped down to 0.24 kV. Also, the tie-breaker is used for contingency situations.

Table 5 shows the specification of the load connected to the feeder bus of the system. The 13.2 kV from the incoming supply is stepped down to 0.24 kV to be compatible with the loads. Table 5. Load ID Name Chiller 1

Chiller 2

Specification

Bus No.

800 kW 1139.4 kVA 0.24 kV 2741 A PF= 75% 3-phase EFF= 93.62

T1 Feeder Bus

101.3 kW 89.29 kVAR 135 kVA 0.24 kV 562.5 A PF= 75% 1-phase (AB) Motor Load: 80%

T2 Feeder Bus

167.2 kW 143 kVAR 220 kVA 0.24 kV 916.7 A PF= 76% 1-phase (BC) Motor Load: 80%

T2 Feeder Bus

Load 1

41.6 kW 31.2 kVAR 52 kVA 0.24 kV 216.7 A PF= 80 % 1-phase (AB)

Bus_2

Load 2

47.12 kW 40.3 kVAR 62 kVA 0.24 kV 258.3 A PF= 76 % 1-phase (BC)

Bus_2

Load 3

32 kW 24 kVAR 40 kVA 0.24 kV 166.7 A PF= 80 % 1-phase (CA)

Bus_2

Load 4

36 kW 27 kVAR 45 kVA 0.24 kV 187.5 A

Bus_2

Lumped Load_1

Lumped Load_2

Lumped Load_3

PF= 80 % 1-phase (AB) Motor Load: 80%

Load 5

Lift #1

Lift #2

Load 6

42.64 kW 29.76 kVAR 52 kVA 0.24 kV 216.7 A PF= 82 % 1-phase (BC)

Bus_2

30 HP 35.51 kVA 0.24 kV 148 A EFF= 90 % PF= 70 % 1-phase (AB)

Bus_3

41.6 kW 29.76 kVAR 52 kVA 0.24 kV 216.7 A PF= 80 % 1-phase (CA)

Bus_3

The specifications such as power rating, power factor, full-load ampacity, and efficiency used in Table 5 were provided by the suppliers in ETAP. The T1 feeder bus supplies the three-phase loads such as Chiller 1 and Chiller 2. While the single-phase loads are connected to T2 Feeder Bus. Bus 2 and Bus 3 are supplied by the T2 Feeder bus and it contains the Load 1 to Load 6 and Lift 1 & 2 single-phase static motors. The full-load ampacity of the load components are validated using manual computation.

Figure 3 presents the short circuit analysis diagram of the power system network simulated through ETAP software. The short circuit analysis determines the fault conditions of the system network.

Figure 3. Short Circuit Analysis of the Power System Network Figure 3 shows the result of the short circuit analysis done in ETAP software. The system network is tested under run device duty calculation where all buses are in fault condition. Bu1 has the symmetrical amperage of 15.584 kA while T1 and T2 Feeder Bus are running at 227.86 kA. The load buses such as Bus 2 and Bus 3 have different amperage because of the variation of loads connected to it.

The table below shows the data results from ANSI Short Circuit Duty Analyzer. Table 6 presents the general results of short circuit duty analyzer conducted in ETAP software. ANSI 3-phase fault study is used as the study type of the system network. It calculates the momentary symmetrical and asymmetrical rms, momentary asymmetrical crest, interrupting symmetrical rms, and interrupting adjusted symmetrical rms short-circuit currents at faulted buses. Table 6. General Result from ANSI Short Circuit Duty Analyzer

Table 6 shows the study type done through ETAP software to check the short circuit analysis of the power system network. The buses connected to the supply are 21 which is the same as the branches. While there is only one power grid and generator that supplies the system.

Table 7 presents the device duty result from ANSI short circuit data analyzer. The critical level alert used is 100% while the marginal level is 95%. Table 7. Device Duty result from ANSI Short Circuit Data Analyzer

Table 7 shows the different types of amperage involved in the short circuit analysis. The symmetrical kA of the buses are ranging from 2 kA to 227 kA wherein buses connected to the transformer have the highest amperage value. The asymmetrical kA of the buses are ranging from 2 kA to 330 kA. The peak kA of the buses are ranging from 4 kA to 561 kA which also indicates the maximum current that flows through the system.

Contingency Situations The figures below show the short-circuit analysis of the power system network under various contingency conditions.

Figure 4. T1, T2 and Standby Generator 1 are out of service Figure 4 shows the short circuit analysis of the power system network wherein T1, T2 and Standby Generator 1 are out of service. There is no current that flows through the system aside from the bus 1 which has 15.309 kA.

Figure 5 shows the short circuit analysis of the power system network wherein T1 and T2 are in-service while Standby Generator is out-of-service. The current flow does not vary in spite of the generator being standby disconnected.

Figure 5. Standby Generator is out-of-service

Figure 6 shows the short circuit analysis of the power system network wherein T1 and T2 are out of service while Standby Generator is in-service. The incoming supply and standby generator are capable of supplying the loads connected in the power system.

Figure 6. T1 and T2 ...