Pos Method

Optimal Placement of Distributed Generation UsingParticle Swarm Optimization

Project Guide:Dr. J. Viswanatha Rao,Professor & HOD,EEE Dept.

V.V.K.Satyakar(10A21D4315)

Power loss in a distribution system is high because of low voltage and hence high current.

The loss minimization in distribution systems has assumed greater significance recently since the trend towards distribution automation will require the most efficient operating scenario for economic viability variations.

There are many methods of loss reduction techniques used like feeder reconfiguration, capacitor placement, high voltage distribution system, conductor grading, DG unit placement.

Distributed Generation (DG) is a promising solution to many Distribution problems such as voltage regulation, power loss, etc.

Optimal placement of DG (OPDG) in distribution network is an optimization problem with continuous and discrete variables.

In this project PSO method is going to be used to determine the optimal location of DG to minimize the total real power loss of the distribution systems.

MATLAB/simulink will be used for testing this methodology.

• Definition:That part of power system which distributes

electric power for local use is known as distribution system.

Distribution system provides a final link between the high voltage transmission system and the consumers.

A radial distribution system has main feeders and lateral distributors.

The main feeder originates from substation and passes through different consumer loads.

Laterals are connected to individual loads.

Generally radial distribution systems are used because of their simplicity.

Power loss in a distribution system is high because of low voltage and hence high current.

The loss minimization in distribution systems has assumed greater significance recently since the trend towards distribution automation will require the most efficient operating scenario for economic viability variations.

Studies have indicated that as much as 13% of total power generated is wasted in the form of losses at the distribution level.

The power losses in distribution systems correspond to about 70% of total losses in electric power systems.

These losses can be considerably reduced through the installation and control of reactive support equipments in distribution feeders.

Furthermore, voltage profiles, power-factor and feeder capability of distribution substations are also significantly improved.

There are many methods of loss reduction techniques used like

feeder reconfiguration capacitor placement high voltage distribution system conductor grading DG unit placement

All these methods are involved with passive element except DG unit placement.

Both DG units and capacitors reduce power loss and improve voltage regulation.

But with DG s loss reduction almost double that of Capacitors.

Distributed Generation (DG) is a promising solution to many Distribution problems such as voltage regulation, power loss, etc.

Distributed or dispersed generation may be defined as a generating resource, other than central generating station, that is placed close to load being served, usually at customer site.

It may be connected to the supply side or demand side of meter.

It can be renewable sources based micro hydro, wind turbines, photovoltaic, etc or fossil fuel based fuel cells, reciprocating engines, micro turbines, etc. In term of size, DG may range from few kilowatts to over 100 megawatts

DG Classifications

From a utility interconnection standpoint, DG systems can be classified

i)by type of electrical converter (or type of generator that interfaces the system to the distribution system)– Synchronous machines– Induction machines– Inverters and static power converters

ii) by type of control:--DG supplying real power only (Type 1):

like photovoltaic systems produce real power only.--DG supplying reactive power only (Type 2):

like synchronous condenser supply reactive power only.--DG supplying real power and consuming reactive power (Type 3):

DGs here will supply real power and in turn absorb reactive power In case of the wind turbines, the wind turbines use induction generators to generate electricity but they consume reactive power to produce real power

--DG regulating the bus voltage (Type 4): In this type, DG units produce real power injection by the

DG will require reactive power to regulate the bus voltage.

Analyzing DG ImpactsDistribution systems, whether they are radial

type systems found in rural or suburban areas, or network type systems found in urban areas are generally designed to operate without any generation on the distribution system or at customer loads.

The introduction of generation sources on the distribution system can significantly impact the flow of power and voltage conditions at customers and utility equipment.

System support benefits include:• Power Loss reduction• Voltage Regulation• Transmission and distribution capacity release• Deferments of new or upgraded T&D

infrastructure• Improved utility system reliability

Distributed generation is small-scale power generation that is usually connected to or embedded in the distribution system.

The problem of DG unit placement consists of determining the locations and sizes and number of DG units to install in a distribution system such that maximum benefits are achieved while operational constraints at different loading levels are satisfied.

Distributed Generation (DG) is a small generator spotted throughout a Distribution network, providing the electricity locally to load customers.

DG can be an alternative for industrial, commercial and residential applications.

DG makes use of the latest modern technology which is efficient, reliable, and simple enough so that it can compete with traditional large generators in some areas.

Placement of DGs is an interesting research area due to economical reason.

Distributed generation systems (such as fuel cells, combustion engines, microturbines, etc) can

reduce the system loss and defer investment on transmission and distribution expansion.

Appropriate size and optimal locations are the keys to achieve it.

Optimal placement of DG (OPDG) in distribution network is an optimization problem with continuous and discrete variables.

Many researchers have used evolutionary methods and algorithms for finding the optimal DG placement.

In this project PSO method is going to be used to determine the optimal location of DG to minimize the total real power loss of the distribution systems.

• Kennedy and Eberhart first introduced PSO in year 1995.• PSO is motivated from the simulation of the behavior of social systems such as fish schooling and birds flocking .

• Birds find food by flocking and not individually.

In a PSO system, particles fly around in a multidimensional search space.

During flight, each particle adjusts its position according to its own experience (This value is called Pbest), and according to the experience of a neighboring particle (This value is called Gbest),make use of the best position encountered by itself and its.

This modification can be represented by the concept of velocity.

The PSO-based approach for solving the OPDG problem to minimize the loss takes the following steps:

Step 1: Input line and bus data, and bus voltage limits.

Step 2: Calculate the loss using distribution load flow based on backward-forward sweep.

Step 3: Randomly generates an initial population (array) of particles with random positions and velocities on dimensions in the solution space. Set the iteration counter k = 0.

Step 4: For each particle if the bus voltage is within the limits, calculate the total loss. Otherwise, that particle is infeasible.

Step 5: For each particle, compare its objective value with the individual best. If the objective value is lower than Pbest, set this value as the current Pbest, and record the corresponding particle position.

Step 6: Choose the particle associated with the minimum individual best Pbest of all particles, and set the value of this Pbest as the current overall best Gbest.

Step 7: Update the velocity and position of particle using eqs. 1 and 2 given below.

Step 8: If the iteration number reaches the maximum limit, go to Step 9. Otherwise, set iteration index k = k + 1, and go back to Step 4.

Step 9: Print out the optimal solution to the target problem. The best position includes the optimal locations of DG or multi-DGs, and the corresponding fitness value representing the minimum total real power loss.

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The methodology is going to be tested in two radial distribution test systems.

The first one is the 33-bus radial system with a total load of 3.72 MW and 2.3 MVar.

The second test system is the 69-bus radial system with a total load of 3.80 MW and 2.69 MVar.

MATLAB/simulink will be used for testing this methodology.

Any Queries???

Thank you……