ANALYSIS AND CONTROL OF MODES OF POWER SYSTEM FOR ENHANCING OPERATIONAL EFFECTIVENESS OF POWER MARKET

- Scope of study: congestion and voltage stability in power market operation of IEEE 39 bus and Vietnam power system in 2016... Design neural network for application of analysis and as

THE UNIVERSITY OF DANANG

TRAN PHUONG NAM

ANALYSIS AND CONTROL OF MODES

OF POWER SYSTEM FOR ENHANCING

The University of Danang

The supervisors 1: Ass Prof Dinh Thanh Viet

The supervisors 2: Prof La Van Ut

Reviewers 1: Prof Tran Dinh Long

Reviewers 2: Ass Prof Vo Ngoc Dieu

Reviewers 3: Prof Nguyen Hong Anh

The dissertation is protected before the council meeting marked

doctoral dissertation at the University of Danang in December 26,

2015 08:30am

Dissertation can be found at:

- National library of Viet Nam, Hanoi

- Learning & Information Resource Center, the University of Danang

INRODUCTION

1 Rationale

Nowadays, the operation of power systems in the power market

model has been researched and applied by many countries In

Vietnam, starting on July 1st, 2012 competitive source power market

has been operation Problem analysis and control of power system

mode to enhance the operational efficiency of the power market, it has

an important role and great significance In particular, assessement

and control of congestion as well as voltage stability power system

are not only safe operation of power system but also economic

operation of power market, it should be considered study

2 Aims of study

- Study and analysis of the power system congestion in power

market operation

- Study and analysis of voltage stability of power system in

power market operation

- Study of FACTS devices for congestion control, voltage

stability control and power market welfare

- Design website model for congestion as well as voltage

stability monitoring in spot market operation

- Study of design congestion as well as voltage stability

monitoring model in spot market operation

3 Subjects and scope of study

- Subjects: LUF factor, dV/dQ, LMP and social welfare; neural

network; SVC and TCSC; information technology infrastructure of

power market

- Scope of study: congestion and voltage stability in power

market operation of IEEE 39 bus and Vietnam power system in 2016

4 Methodology

From document, experiment study and mathematical model

CHAPTER 1: OVERVIEW OF POWER MARKET

AND POWER SYSTEM OPERATION

IN POWER MARKET MECHANISM

1.1 Deregulate electricity sector and towal competitive power

market

Electricity sector restructuring has been researched and applied

by many countries Depending on the characteristics of the power

system, political mode, the restructure purpose of each country is

different so that electricity sector restructuring is different

1.2 Introduction to competitive power markets

Power market models has been introduted as: competitive power

generation market with a single buyer, competitive wholesale power

market, competitive retail power market

1.3 Introduction to power market model in the world and

Vietnam

Power market models has been introduted as: Asia power market,

Australia power market, United states of america power market,

Europe power market, Vietnam power market

Fig 1.5: The levels of development of the Vietnam power market

Testing Full Testing Full Testing Full

1.4 Power market operation

1.4.1 Day ahead market and spot market

Fig 1.7: Day ahead market and spot market

1.4.2 Bid, auction and mobilization schedue in power market

The auction is arranged according to the capacity ranges from

low to high price for supply curves and vice versa for demand curves

Auction in the power market is operated by SMO, which is based on

the quotations of the buyer and the seller

1.4.3 Optimal power flow in the power market

The objective function is a minimum of social welfare in total:

1.4.4 Some economic criteria in the power market

Locational marginal price - LMP at Busi is three components

included in the marginal price at reference bus, marginal loss cost

from reference bus to Busi and marginal congestion price from

reference bus to Busi:

Spot market (Day D) Day ahead market

(Day D-1) Day D+1

GenCo/

DisCo

SMO

1.5.1 Analysis and control congestion

- Congestion analysis methods: Congestion analysis on line

utilization factor - LUF, congestion analysis on locational marginal

price - LMP

- Methods of congestion control and management: using

economics method such as locational marginal price - LMP, Financial

Transmission Right - FTR; using techniques such as building new

lines, upgrading and overload protection for the old line; adding

compensation devices to increase power system control (fixed

compensation and FACTS devices…)

1.5.2 Analysis and control voltage stability

- Voltage stability analysis methods: Continuation power flow -

CPF, V-Q sensitivity

- Voltage control methods: Excitation current adjusting of the

generator, output voltage adjusting of transformer by voltage fixel

divider or on load tap changer - OLTC, using compensation device for

change voltage loss on the line as synchronous compensator, fixed

capacitor, FACTS devices…

1.5.3 The impact of power system modes control on power market’s

criterias

Power system modes control will change power market’s

criterias in formulas 1.11, 1.12 and 1.17

CHƯƠNG 2: ANALYSIS AND ASSESSMENT

VOLTAGE STABILITY OF POWER SYSTEM IN

POWER MARKET OPERATION 2.1 Background

With analysis and control of power system’s modes in power

market condition, analysis and assessement voltage stability through

dV/dQ sensitivity will be implemented the lager number of calculation

to implement system of equations Power system in power market

condition is heavily influenced from the power market elements (bid,

auction, mobilization schedule…) Need to find a new analysis and

assessement voltage stability for power market

2.2 Voltage stability of power system

Voltage stability related to the ability to capacity balance of the

load buses, particularly reactive power balance

2.3 Analysis and assessement voltage stability of power system in

Types of error of neural network assessement between target

value ti and assessement value ai can be determined as:

i i

e MAPE

   (2.13) Mean Squared Error: 2

1

1( )

n

i i

n 

  (2.14) Where: ti is target value, ai is assessement value, n is the

number of text sample

2.3.3 Design neural network for application of analysis and

assessement voltage stability of power system in spot market

- For basic neural network structure:

Fig 2.6: MLP neural network model with basic structure

- For neural network structure of proposal dissertation:

P g T

Input Hidden Output

Fig 2.7: MLP neural network model with structure of proposal

dissertation (VSA-PM)

2.3.4 Algorithm flowchart of neural network training in voltage

stability assessement of power system in spot market

Algorithm flowchart is impletemented as: create neural

network; create learning text sample; create weight, bias, the number

of iterations; training by Levenberg - Marquardt algorithm; checking

stop condition; saving neural network structure with new weight and

bias; text neural network

2.3.5 Application of neural network in analysis and assessement

voltage stability of IEEE 39 bus power system in spot market

- Analysis neural network training perpormance:

Fig 2.11: Error MSE: (a) basic structure, (b) proposal structure

P g T

Input Hidden Output

- Text and analysis neural network with examined data:

Fig 2.14: Distribution of actual error, absolute error and MAE

with basic structure

Fig 2.17: Distribution of actual error, absolute error and MAE

with proposal structure

(b) Distribution of absolute error, MAE=0.0005

(c) Distribution of absolute percentage error, MAPE=0.038%

Absolute error MAE

Absolute percentage error MAPE

(a) Distribution of actual error

(b) Distribution of absolute error, MAE=0.0005

(c) Distribution of absolute percentage error, MAPE=0.038%

Absolute error MAE

Absolute percentage error MAPE

(a) Distribution of actual error

- Text and analysis neural network with mutations data:

(a) (b)

Fig 2.20: Basic structure: (a) MAE, (b) MAPE

(a) (b)

Fig 22: Proposal structure: (a) MAE, (b) MAPE

Therefore, proposal neural network structure shows

assessement performance through error of MSE, MAE, MAPE are

better than the basic neural network structrure for IEEE 39 bus power

system

2.3.6 Application of neural network for analysis and assessement

voltage stability of southern Vietnam power system in 2016 in spot

market

- Analysis neural network training perpormance:

Fig 2.23: Error MSE: (a) basic structure, (b) proposal structure

- Text and analysis neural network with examined data:

Fig 2.24: Distribution of absolute error, absolute percentage error

with basic structure

Fig 2.25: Distribution of absolute error, absolute percentage error

with proposal structure

(a) Distribution of absolute error, MAE=2.89e-07

(b) Distribution of absolute percentage error, MAPE=0.4370%

Absolute error MAE

Absolute percentage error MAPE

(a) Distribution of absolute error, MAE=4.13e-07

(b) Distribution of absolute percentage error, MAPE=0.5887%

Absolute error MAE

Absolute percentage error MAPE

Training Best

Epochs (b)

- Text and analysis neural network with mutations data:

Fig 2.28: Assessement dV/dQ, error MAE and error MAPE of

basic structure with disconnected branch 500KV

Tan Dinh - Song May

Fig 2.29: Assessement dV/dQ, error MAE and error MAPE of

proposal structure with disconnected branch 500KV

Tan Dinh - Song May

Sample value (PowerWorld)

ANN value (Matlab)

Sample value (PowerWorld)

ANN value (Matlab)

Bus Bus

Therefore, proposal neural network structure shows

assessement performance through error of MSE, MAE, MAPE are

better than the basic neural network structrure for Southern Vietnam

bus power system in 2016

CHAPTER 3: STUDY AND APPLICATION OF FACTS

DEVICE CONTROL OF MODES OF POWER SYSTEM FOR

ENHANCING EFFECTIVENESS OF POWER MARKET

3.1 Background

With premium features and benefits of FACTS devices,

research and installation of FACTS will be expected the effective

operation of the power system and power market

3.2 Overview of FACTS device

With specifications, SVC, STATCOM, UPFC devices can be

utilized to enhance voltage stability as well as TCSC, UPFC devices

can be utilized to control power flow

With economic criteria, cost of SVC and TCSC following

KVAr are cheaper than other FACTS devices

Dissertation choose SVC and TCSC to calculate and connect

operational power system in conditional power market

3.3 Application of choice placement of FACTS device for modes

control of power system in power market operation

3.3.1 The impact of FACTS device to modes control of power system

to power market’s criterias

Application of FACTS device will change power flow in power

system, so criterias of GenCos, DisCos and market will change as

formulas from 1.13 to 1.17

3.3.2 Methodology of choice placement of FACTS device into power

system in power market operation

With methodology of choice placement of TCSC as well as SVC

into power system in power market operation, it will be analyzed the

technology first, and then it will analyze the economic after

3.3.3 Assessment FACTS device efficiency to enhance benefit of

electricity losses

Dissertation proposes choice of placement of FACTS device

following criteria for benefit of electricity losses fall:

( ) ( )

FACTS L

B D A c $ (3.20) Criteria for benefit of electricity losses fall with scenarios:

_ 1

( )

n FACTS FACTS scenarioi

3.4 Analysis and choice of placement of FACTS device in IEEE

39 bus power market

3.4.1 Analysis and choice of placement of SVC

SVC is located alternate weak buses of voltage stability, and P-V

is analyzed next, effectiveness achieves positive effects The slope of

the P-V curves are reduce, voltage Vmin of curves are improved with

the connection cases of SVC

Tab 3.3: Change criterias of P-V cuver with connection cases of SVC

Without SVC Bus 26 Bus 27 Bus 28 Bus 29

V min (pu) 1,015 1,016 1,016 1,028 1,053

With two SVC effective cases, case of SVC connection at bus

29 shows the highest economic efficiency through BL SVC value

Fig 3.14: Annual BL SVC criteria in connection cases of SVC with

control V=1,02pu and V=1,03pu

3.4.2 Analysis and choice of placement of TCSC

With two TCSC effective cases, case of TCSC connection at

branch 4-14 shows the highest economic efficiency through BTCSC L

value

Fig 3.19: Annual BL TCSC criteria in connection cases of TCSC with

control X TCSC = 0,5X L and X TCSC = 0,7X L

3.5 Analysis and choice of placement of FACTS device in

Vietnam power market in 2016

3.5.1 Analysis and choice of placement of SVC

Control value Average value Control value Average value

With three SVC effective cases, case of SVC connection at bus

Tan Dinh shows the highest economic efficiency through BL SVC value

Fig 3.26: Annual BL SVC criteria in connection cases of SVC with

control V=1,02pu and V=1,03pu

3.5.2 Analysis and choice of placement of TCSC

With two TCSC effective cases, case of TCSC connection at

branch Di Linh - Tan Dinh shows the highest economic efficiency

Control value Average value

CHAPTER 4: STUDY AND DESIGN OF MONITORING AND

CONTROL MODES OF POWER SYSTEM IN

POWER MARKET OPERATION 4.1 Background

Nowadays, the information technology infrastructure of

electrical sector in many countries around the world are upgrading

development However, when the power market operation, the

completion of hardware and software of the information technology

infrastructure is an important issue of power market

4.2 Overview of SCADA/EMS system

SCADA/EMS is supervisory control and data acquisition/Energy

Management System This system is the optimal control center

solution to enable a secure and efficient operation of the electric

power system

4.3 Introduction of SCADA/EMS system of Vietnam power

system

According to overall assessment, SCADA/EMS should be further

upgraded to meet the high operation requirements as well as

mechanism power system

4.4 Connection of SCADA/EMS with operational system of power

market

In mechanism power market, SCADA/EMS system is connected

directly to power market operational system SCADA/EMS system

focus to collect, monitor and control power system, operational

system of power market focus to operate transaction of the members

participating in the power market