Dominion Energy®

Rebecca Rye

1 November 20171

Real-Time Testing of STATCOM and

SVC Controllers

Acknowledgements

1 November 20172

Kyle ThomasDr. Hung-Ming Chou

Murat SezerArnold Rischer

Hezi TouafAdam Sparacino

Chathura Patabandi

Power Electronic Devices in Power Systems

1 November 20173

Solar farm

SVC & STATCOM (for voltage regulation)

Wind farm

High Voltage Direct Current

(HVDC)

Types of Shunt Devices for Voltage Regulation

1 November 20174

Fixed Cap/Fixed Reactor

SVC STATCOM

Switch mechanism Mechanical Power Electronics Power Electronics

Reactive power (Q) control method Manual / Automatic Automatic Automatic

Q change step size Large Small Small

Both capacitive & inductive? No Yes Yes

Need harmonic filter? No Large filter Small filter

V & I Signals

GTAO

RTDSHardware-in-the-Loop (HIL) Experiments on RTDS

1 November 20175

STATCOM or SVC controller

GTFPIGTDI

Breaker Signals

GTAI Converter States

Circuit model

Introduction to the STATCOM

1 November 20176

Static Synchronous CompensatorA regulating device that can act as either a source or sink of reactive power using IGBTs

DC/AC Multilevel converter

2-level converter 3-level converter

Introduction to the STATCOM

1 November 20177

Static Synchronous CompensatorA regulating device that can act as either a source or sink of reactive power

Reactive power control

Current control

Switch control

Current reference

Dutyratio

Reactive power control(1) Fixed Q mode / Manual mode (2) Voltage Control Mode

STATCOM RTDS Tests

1 November 20178

Functional Performance Tests (FPT)- Operational behavior

Start up and shut down V/Q characteristic Gain controller test Stability controller Redundancy switchover

System diagram

DC/AC converter

Voltage source

STATCOM RTDS Tests

1 November 20179

Mode transfer from fixed Q (FQM) to voltage control (VCM)

(1) In fixed Q (FQM) Q reference = 0

(2) Mode transfer

(4) Operation point in voltage control (VCM)

𝑉𝑉

𝑄𝑄CapacitiveInductive

Q >0

(3) Gain of VCM controller is adjusted

Q

STATCOM RTDS Tests

1 November 201710

System diagram

Dynamic Performance Tests (DPT)- Transient behavior

Faults Load switching External transformer energization

STATCOM RTDS Tests

1 November 201711

Dynamic performance of STATCOM in phase to phase fault

t1

t1 : Line to line fault

t2

t2 : STATCOM blockedbecause of undervoltage

t3

t3 : Fault is clearSTATCOM is unblocked

Digital Signals

Introduction to the SVC

1 November 201712

Static VAR CompensatorA device which regulates voltage by injecting or removing reactive power using:

• TCR: Thyristor Controlled Reactor• TSC: Thyristor Switched Capacitor

IV①

②

V

I ① fires

② fires

GATE

GATE

Light Triggered Thyristor:

Introduction to the SVC

1 November 201713

Reactive power control

Susceptance control

Valve control

Susceptancereference

Firing Angle

Reactive power control(1) Susceptance Control (Q-Mode) (2) Voltage Regulator (AVR)

Static VAR CompensatorA device which regulates voltage by injecting or removing reactive power

SVC RTDS Tests

1 November 201714

System Verification Tests- Operation and static/dynamic characteristics

Start up & shut down Protection V-I characteristics Faults

System diagramVoltage source w/ impedance

TCR-200 to 0 Mvar

TSC+200 or 0 Mvar

5th & 7th

Harmonic Filter+50 Mvar

Spare 5th & 7th

Harmonic Filter+50 Mvar

3rd

Harmonic Filter+72 Mvar

250 MVA500 kV : 25 kV

500 kV

25 kV bus

SVC – VC Mode

1 November 201715

Vsys1

B

InductiveCapacitiveI (pu)

V (pu)

VrefA

Linear Control Range

SVC DynamicCharacteristic

USED WITH EXPRESS AND SPECIFIC PERMISSION FROM MITSUBISHI ELECTRIC CORPORATION

SVC RTDS Tests

1 November 201716

Performance of SVC in phase to ground fault under voltage-control mode

0.80.85

0.90.95

11.05

V (p

u)

V

-2

-1

0

1

2

Cur

rent

(kA

) Transformer Current ATransformer Current BTransformer Current C

-100

0

100

200

300

Q (M

var)

SVC_Q

-40

-20

0

20

40

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5

Cur

rent

(kA

)

t (s)

Fault Current

t1

t1 : L-G fault applied

t2

t2 : SVC injects Q to increase V

t3

t3 : Fault is clear; SVC’s Q brifelyincreases to regulate voltage to 1 pu

t4 : SVC injects less Q as voltage is boosted to reference value

t4

SVC – SC Mode

1 November 201717

QA

A

InductiveCapacitiveI (pu)

V (pu)

ref

Qref

Linear Control Range

SVC DynamicCharacteristic SVC Steady-State Characteristic

USED WITH EXPRESS AND SPECIFIC PERMISSION FROM MITSUBISHI ELECTRIC CORPORATION

020406080

100120140

0 20 40 60 80 100 120

Q (M

var)

t (s)

SVC_Q

SVC RTDS Tests

1 November 201718

t1

t1 : System voltage change; SVC responds dynamically

t2

t2 : System voltage settles; SVC’s reactive powerbegins to move toreference value

1

1.005

1.01

1.015

1.02

1.025

V (p

u)

V_Actual

0

0.03

0.06

0.09

0.12

0.15

I (kA

)

I_Actual

t3

t3 : SVC’s reactive power returns to Qref value

Qref = 50 Mvar

Performance of SVC in phase to ground fault under susceptance-control mode

RTDS Tests – Conclusions

1 November 201719

1) Real STATCOM & SVC controllers can be tested using hardware-in-the-loop technologyon RTDS racks.

2) Verified the functionality and operation of Dominion Energy’s new controllers per the manufacturers’ specifications.

3) Understand the controllers and able to predict the response of the controllers in various scenarios.

4) Further tested the functionality of the controllers by performing more protection sequences and various kinds of faults in the simple model.

Interaction of the STATCOM and SVC

1 November 201720

Interaction Assessment of the STATCOM and SVC

1 November 201721

Dynamic interaction - voltage recovery time during faults

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Reco

ver t

ime

(ms)

Location of recovery time measurement

No STATCOM nor SVC Only STATCOM Only SVC Both STATCOM & SVC

Bus 4 Bus 3 Bus 11 Bus 1 Bus 17

Progress

1 November 201722

Individual simulations of the real SVC and STATCOM controllers are completed using the RTDS simulation equipment and hardware-in-the-loop functionality.

Operational and dynamic performances of the STATCOM and the SVC are tested and meet the criteria from vendor reports.

Using an equivalent system model of an urban area, the STATCOM and the SVC controllers are successfully included in the same simulation. No negative interactions are found between the SVC and STATCOM when in close proximity.

All tests procedures & results obtained are documented; documentation can be used for training purposes

Future work(1) Build virtual STATCOM or SVC models in RTDS that emulate the real controller.(2) Use the virtual models to study the interactions of multiple devices in the same network.

Thank you!

1 November 201723

Appendicies

1 November 201724

Dominion Energy’s SVC - Hardware

1 November 201725

TCR-200 to 0 Mvar

TSC+200 or 0 Mvar

5th & 7th HF+50 Mvar

3rd HF+72 Mvar

250 MVA500 kV : 25 kV

500 kV bus

25 kV bus

Inductive Capacitive

QCOMPONENT

(Mvar)

QSVC

(Mvar)

0+50

+250

-200

-100

-150 00

-50

+200

-50

-150 +250

0

Using Reactive Power for Voltage Regulation

1 November 201726

InductorCapacitorResistor

𝑉𝑉𝐼𝐼

𝑉𝑉𝐼𝐼

𝐼𝐼𝑉𝑉

Reactive Power for Voltage Regulation

November 1, 201727

Original

𝑉𝑉𝑔𝑔 𝑉𝑉𝐿𝐿

𝐼𝐼𝐿𝐿

𝑉𝑉𝑔𝑔

𝐼𝐼𝐿𝐿

∆𝑉𝑉

Capacitive compensation𝐼𝐼𝐿𝐿

∆𝑉𝑉

Inductive compensation𝐼𝐼𝐿𝐿

∆𝑉𝑉

𝑉𝑉𝐿𝐿∆𝑉𝑉

𝐼𝐼𝐿𝐿

𝑉𝑉𝑔𝑔

∆𝑉𝑉

𝑉𝑉𝑔𝑔

𝐼𝐼𝐿𝐿

𝑉𝑉𝐿𝐿 ∆𝑉𝑉𝑉𝑉𝐿𝐿