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Enhancement of the transient stability performance of power systems with high share of wind generators equipped by using power-angle modulation controllers

Dr.ir. José RuedaAssociate Professor Power System Stability, Control, and Optimization

7th September 2020

IV International Workshop on Dynamic Stability Challenges of the Future Power Grids

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OUTLINE

1. The future multi-energy system: stability concerns

2. Power-angle modulation

3. Numerical Simulations

4. Concluding remarks

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OUTLINE

1. The future multi-energy system: stability concerns

2. Power-angle modulation

3. Numerical Simulations

4. Concluding remarks

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1.1 THE FUTURE MULTI-ENERGY SYSTEM

New features:

High uncertainty

Changing system properties

Faster dynamic phenomena

Multi-controller interactions

MTDC

AC System

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1.2 STABILITY CONCERNS DUE TO ENERGY TRANSITION

Source: MIGRATE Deliverable D1.1 - Report on Systemic Issues (2016)

TSO: Transmission system operatorPE: Power electronic converter

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1.3 MIGRATE H2020: NEW CONTROL METHODS FOR HIGHER RES

Source: MIGRATE Brochure (2019)

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OUTLINE

1. The future multi-energy system: stability concerns

2. Power-angle modulation

3. Numerical Simulations

4. Concluding remarks

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2.1 POWER-ANGLE MODULATION - MOTIVATIONReduced size test system Synthetization of input signals for wide-area control

What kind of post-fault active power response by decoupled renewable generationcan effectively support power system transient stability?

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PAM controller superimposed on WG model of IEC 61400-27-1

2.2 POWER-ANGLE MODULATION – BASIC NOTIONS

Structre of the Power-Angle Modulation (PAM) controller

AP Controlsystems

Aerodynamics and Mechanical model

P choice and reduction

Measurements:

Frequency VoltagePower

Wind Speed

Currentcontrol

RP Controlsystems

Pitch control

HG

An

Figure 4

idre

f

iqre

f

PAMin HGAn

Example parameter values:

KPAM = 10 pu; TPAM = 10 ms;

Tdeactivation∈ [5s 15s] → Depending on the time response of primary frequency control.

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Reduced size test system

𝑥𝑥1 = 𝑥𝑥𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 + 𝑥𝑥𝑙𝑙𝑆𝑆𝑆𝑆𝑙𝑙1

𝑃𝑃𝑙𝑙𝑆𝑆𝑆𝑆 =𝐸𝐸𝑉𝑉2𝑥𝑥1

sin δ − θ2

𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁 =𝑉𝑉2𝑉𝑉3𝑥𝑥2

sin θ2 − θ3

𝑃𝑃𝑊𝑊𝑆𝑆𝑆𝑆𝑊𝑊 = 𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁 − 𝑃𝑃𝑙𝑙𝑆𝑆𝑆𝑆

2.2 POWER-ANGLE MODULATION – BASIC NOTIONSPower-angle curves of the SG1 under different ratios between 𝑥𝑥1 and 𝑥𝑥2

Without WG1 50% share of WG1

PWG1 causes a phase displacement and a modulation of the magnitude of the power-angle curve of SG1:

These effects depend on the different ratios between 𝑥𝑥1 and 𝑥𝑥2.

Control of PWG1 is an option to support the transient stability of SG1.

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Reduced size test system

𝑥𝑥1 = 𝑥𝑥𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 + 𝑥𝑥𝑙𝑙𝑆𝑆𝑆𝑆𝑙𝑙1

𝑃𝑃𝑙𝑙𝑆𝑆𝑆𝑆 =𝐸𝐸𝑉𝑉2𝑥𝑥1

sin δ − θ2

𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁 =𝑉𝑉2𝑉𝑉3𝑥𝑥2

sin θ2 − θ3

𝑃𝑃𝑊𝑊𝑆𝑆𝑆𝑆𝑊𝑊 = 𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁 − 𝑃𝑃𝑙𝑙𝑆𝑆𝑆𝑆

2.2 POWER-ANGLE MODULATION – BASIC NOTIONSRotor angle and P after a 200 ms three-phase fault (t = 1 s) at Bus 2

Limitation of current approach for post-fault active recovery:

Fast nullification and recovery of Pwind → negative collateral impact on SG1

→ Modulated P recovery is proposed as a solution.

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OUTLINE

1. The future multi-energy system: stability concerns

2. Need of enhanced assessment tools

3. Numerical Simulations

4. Concluding remarks

13The fault location influences the level of support provided by WGs equipped with PAM

Without PAM With PAM Without PAM With PAM

3.1 MODIFIED IEEE 9 BUS SYSTEM (52 % WIND POWER SHARE)Pre-disturbance condition

Simulated three phase faults. FCT = 120ms.

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Pre-disturbance condition

3.1 MODIFIED IEEE 9 BUS SYSTEM (52 % WIND POWER SHARE)

PAM outperforms FRT and Voltage Dependent Active Current (VDAC) reduction Increase from 52% to 75% feasible due to WGs equipped with PAM.

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3.2 POWER HARDWARE-IN-THE-LOOP (P-HIL) TEST-SETUPRTDS

REAL TIME TARGET (RTT)

Grid Side Converter

Grid Connection3-Phase, 400 V,

50 Hz

Grid Emulator

Through Aurora protocol

Control Signals

Grid Voltage, Frequencyand Current

Control Signals

Measured Current/Power

Grid Voltage, Frequency

Measured Current/Power

Applications: Grid code compliance testing

of control functions of powerelectronic converters

HIL testing of new controlstrategies for mitigation oftransient stability threats

HIL testing of new controlstrategies for fast activepower-frequency control

HIL testing of new controlmethods for delivery of ancillaryservices by Electrolysers

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Fault Duration: 6 cycles3.3 P-HIL BASED TEST OF PAM

Rotor Angle Deviation

PAM acting on grid side converter

• Mock-up grid side converter is capable of fastmodulating active and reactive power according to PAMcontrol during a short circuit.

• Improvement in transient stability performancebrought by PAM was verified by HIL.

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3.4 66% SHARE OF WIND GENERATION IN THE GB SYSTEM

Three-phase fault at Line 6-9. FCT = 120ms

0 2 4 6 8 10

Time (Seconds)

-80

-60

-40

-20

0

20

SG

RA

(D

eg

ree

s)

Scotland

G3G5G7G8

0 2 4 6 8 10

Time (Seconds)

-80

-60

-40

-20

0

20

SG

RA

(D

eg

ree

s)

North EnglandG11G16

0 2 4 6 8 10

Time (Seconds)

-80

-60

-40

-20

0

20

SG

RA

(D

eg

ree

s)

East EnglandG19G20

0 2 4 6 8 10

Time (Seconds)

-80

-60

-40

-20

0

20

SG

RA

(D

eg

ree

s)

West EnglandG13G15

WGs of Scotland & East zones equipped with PAM

Similar responses obtained when: The WGs of all GB zones are equipped with PAM. Only WGs of the zones prone to transient instability

(Scottish & Eastern England) are equipped with PAM.

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3.4 66% SHARE OF WIND GENERATION IN THE GB SYSTEM

Influence of time delays.

Performance with different input signals (remote vs local measurements).

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OUTLINE

1. The future multi-energy system: stability concerns

2. Need of enhanced assessment tools

3. Numerical Simulations

4. Concluding remarks

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4 CONCLUDING REMARKS

With studied systems, transient stability ensured until 75% share of PEIG. WGs in weakareas (prone to instability) candidates for PAM.

Effective support if WGs with PAM are electrically close to vulnerable SGs. Improvement incase of larger distance to reference machine

WGs with PAM are more effective when remote inputs are considered.

Lower performance of PAM if time delay is higher than 170ms.

Future work: Application of the PAM controller to other power electronic interfaced devices

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4 CONCLUDING REMARKS

Further reading:

Arcadio Perilla ,José Luis Rueda Torres, Stelios Papadakis, Elyas Rakhshani, Mart van der Meijden, andFrancisco Gonzalez-Longatt, “Power-Angle Modulation Controller to Support Transient Stability of PowerSystems Dominated by Power Electronic Interfaced Wind Generation,” Energies 2020, 13(12), 3178; 19 Jun2020, https://doi.org/10.3390/en13123178.

Arcadio Perilla, Stelios Papadakis, Jose Luis Rueda Torres, Mart van der Meijden, Peter Palensky, andFrancisco Gonzalez-Longatt, “Transient Stability Performance of Power Systems with High Share of WindGenerators Equipped with Power-Angle Modulation Controllers or Fast Local Voltage Controllers,”Energies 2020, 13(16), 4205; 14 Aug 2020, https://doi.org/10.3390/en13164205.

Thanks for your attention!