Master Economic Dispatch: Optimize Power System Operations for Efficiency

Question 1

In the context of power system operation, which method focuses on optimizing power generation schedules within a short-term horizon, typically one hour?

Accepted Answer

Economic dispatch

Answer

Unit commitment

Answer

Optimal power flow

Answer

Transmission congestion management

Question 2

Which constraint primarily limits the maximum power output of a generator in economic dispatch?

Accepted Answer

Thermal limits

Answer

Voltage stability limits

Answer

Transmission capacity limits

Answer

Fuel availability limits

Question 3

What is the primary objective of unit commitment in power system planning?

Accepted Answer

To determine the optimal combination of generators to meet demand

Answer

To schedule generator outputs to minimize operating costs

Answer

To prevent cascading outages

Answer

To maximize system reliability

Question 4

What is a key advantage of using Lagrangian relaxation in economic dispatch?

Accepted Answer

It can handle non-convex cost functions

Answer

It is computationally efficient

Answer

It provides a global optimum

Answer

It is simple to implement

Question 5

In the context of economic dispatch, what is the primary role of spinning reserve?

Accepted Answer

To provide backup power in case of generator outages

Answer

To regulate voltage

Answer

To balance supply and demand

Answer

To improve system reliability

Question 6

What is the fundamental distinction between economic dispatch and generation scheduling in power systems?

Accepted Answer

Economic dispatch optimizes generator outputs, while generation scheduling determines the operational status of generators

Answer

Economic dispatch considers short-term operations, while generation scheduling focuses on long-term planning

Answer

Economic dispatch minimizes operating costs, while generation scheduling maximizes system reliability

Answer

They are essentially interchangeable terms

Question 7

Which method for minimizing power system operating costs considers transmission losses?

Accepted Answer

Lagrangian relaxation based dispatch

Answer

Incremental cost based dispatch

Answer

Linear programming based dispatch

Answer

Dynamic programming based dispatch

Question 8

Primary goal of generation scheduling in power systems?

Accepted Answer

Minimizing generation cost

Answer

Maximizing system reliability

Answer

Optimizing reserve capacity

Answer

Minimizing environmental impact

Question 9

Significance of the lambda value in economic dispatch?

Accepted Answer

Marginal cost of generation

Answer

Generator output adjustment

Answer

Optimal power flow determination

Answer

Operational efficiency indication

Question 10

How do environmental regulations impact the economic dispatch process?

Accepted Answer

Environmental regulations make economic dispatch more complex by adding constraints.

Answer

Environmental regulations have no effect on economic dispatch.

Answer

Environmental regulations make economic dispatch simpler by reducing factors to consider.

Question 11

Which of the following unit commitment optimization techniques incorporates the variation of generation costs over time?

Accepted Answer

Dynamic programming

Answer

Lagrange relaxation

Answer

Mixed-integer linear programming

Answer

Genetic algorithms

Question 12

What is the primary objective of economic dispatch in power systems?

Accepted Answer

Minimizing total generation cost while adhering to system constraints

Answer

Maximizing system efficiency

Answer

Reducing environmental impact

Answer

Increasing renewable energy generation

Question 13

In economic dispatch, what aspect does the Lagrange multiplier represent?

Accepted Answer

The incremental cost of easing the power balance constraint

Answer

The optimal generation schedule

Answer

System losses

Answer

Fuel cost of generators

Question 14

Which advantage does mixed-integer linear programming offer in unit commitment optimization?

Accepted Answer

Ability to handle integer variables (on/off states of generators)

Answer

Computational efficiency

Answer

Wide availability in commercial software

Answer

Simultaneous optimization of both unit commitment and economic dispatch

Question 15

What is the function of the B-coefficient matrix in economic dispatch?

Accepted Answer

Representing the change in generation cost with respect to generation

Answer

Calculating the slack bus

Answer

Determining the optimal voltage profile

Answer

Solving power flow equations

Question 16

What is the correct order of steps to solve a unit commitment problem in power systems?

Accepted Answer

Define system parameters, predict demand, optimize unit dispatch, schedule unit on/off times.

Answer

Optimize unit dispatch, schedule unit on/off times, define system parameters, predict demand.

Answer

Predict demand, optimize unit dispatch, define system parameters, schedule unit on/off times.

Answer

Schedule unit on/off times, predict demand, define system parameters, optimize unit dispatch.

Question 17

The fundamental goal of economic dispatch in power systems is to:

Accepted Answer

Minimize the cost of power generation

Answer

Maximize the efficiency of power plants

Answer

Ensure the stability of the power grid

Answer

Reduce the environmental impact of power generation

Question 18

In a power system load-duration curve, the area under the curve signifies:

Accepted Answer

The total energy consumed over a specified time period

Answer

The average load demand throughout the time period

Answer

The maximum load demand experienced during the period

Answer

The optimal power plant capacity for meeting the demand

Question 19

The incremental cost of generation in economic dispatch represents:

Accepted Answer

The change in operating cost resulting from a small change in power output

Answer

The total cost of generating a specific amount of power

Answer

The minimum cost at which power can be generated

Answer

The cost of fuel used to generate power

Question 20

In economic dispatch, the merit order is used to:

Accepted Answer

Rank generators based on their operating costs, with lower-cost generators being dispatched first

Answer

Determine the maximum power output of each generator

Answer

Ensure equal utilization of all generators

Answer

Minimize transmission losses

Question 21

A key benefit of adopting a centralized approach to economic dispatch is:

Accepted Answer

Optimal coordination of generator operation, leading to reduced operating costs

Answer

Increased flexibility in responding to load variations

Answer

Improved system reliability and stability

Answer

Reduced environmental emissions

Question 22

A potential drawback associated with decentralized economic dispatch is:

Accepted Answer

Suboptimal system operation due to lack of coordination between generators

Answer

Higher operating costs resulting from independent decision-making

Answer

Increased risk of power outages

Answer

Difficulty in integrating renewable energy sources

Question 23

What is the definition of incremental cost of generation?

Accepted Answer

The cost associated with increasing generation output by one unit

Answer

The cost associated with decreasing generation output by one unit

Answer

The cost associated with maintaining constant generation output

Answer

The cost associated with repairing failed generators

Question 24

Which of the following factors does not affect the economic dispatch of renewable energy sources?

Accepted Answer

Fuel prices and availability

Answer

Intermittency and variability of renewable generation

Answer

Cost and availability of energy storage systems

Answer

Environmental regulations and policies

Question 25

What is a key advantage of using a probabilistic approach to economic dispatch?

Accepted Answer

It can account for the uncertainty and variability in renewable energy generation

Answer

It can improve the reliability of the power system

Answer

It can reduce the operating cost of the power system

Answer

It simplifies the optimization problem

Question 26

What is the primary objective of economic dispatch?

Accepted Answer

Minimize the total generation cost while meeting demand and maintaining system security

Answer

Reduce greenhouse gas emissions

Answer

Increase the power transmission capacity

Answer

Maximize the generation efficiency

Question 27

Which method is most commonly used for solving the economic dispatch problem?

Accepted Answer

Lambda-iteration method

Answer

Genetic algorithm

Answer

Dynamic programming

Answer

Gauss-Seidel method

Question 28

How does increasing the generation of a unit typically affect its marginal cost?

Accepted Answer

Increases

Answer

Varies randomly

Answer

Decreases

Answer

Remains constant

Question 29

Which of the following constraints is typically considered in economic dispatch?

Accepted Answer

Unit capacity limits and demand balance

Answer

Voltage stability only

Answer

Transmission line thermal limits only

Answer

Frequency deviations only

Question 30

What is the purpose of the cost curve in economic dispatch?

Accepted Answer

Represents the relationship between generation and marginal cost for each unit

Answer

Predicts future fuel prices

Answer

Shows the total generation cost for all units

Answer

Estimates the transmission losses

Question 31

Which of the following is a benefit of economic dispatch?

Accepted Answer

Reduces operating costs

Answer

Increases power transmission capacity

Answer

Guarantees reliable power supply

Answer

Improves voltage stability

Question 32

What is the primary responsibility of the system operator in economic dispatch?

Accepted Answer

Coordinates the operation of generation units to meet demand efficiently

Answer

Sets the electricity prices

Answer

Performs unit commitment

Answer

Maintains transmission lines

Question 33

In power systems, what is the main purpose of economic dispatch?

Accepted Answer

Minimizing the overall operating costs of the system

Answer

Maximizing the power output of each power plant

Answer

Balancing the load demand across different regions of the grid

Answer

Reducing greenhouse gas emissions from power generation

Question 34

The objective of economic dispatch is to:

Accepted Answer

Minimize the total generation cost

Answer

Maintain constant system frequency

Answer

Maximize the system power output

Question 35

Which of the following is NOT a factor influencing economic dispatch calculations?

Accepted Answer

Transmission line voltage

Answer

Fuel cost

Answer

System power demand

Answer

Generator capacity limits

Question 36

A benefit of using a stochastic approach for economic dispatch is:

Accepted Answer

Accounts for uncertainties in system conditions and load demand

Answer

Is less computationally intensive than deterministic methods

Answer

Always finds the globally optimal solution

Question 37

Which of the following is NOT a type of reserve margin used in power system operation?

Accepted Answer

Demand reserve

Answer

Regulation reserve

Answer

Non-spinning reserve

Answer

Spinning reserve

Question 38

The primary purpose of unit commitment in power system operation is:

Accepted Answer

Scheduling the operation of generating units to meet system demand at minimum cost

Answer

Determining the optimal locations for new power plants

Answer

Ensuring compliance with environmental regulations

Question 39

Which of the following is a constraint considered in the unit commitment problem?

Accepted Answer

Minimum up and down times of generators

Answer

Line losses

Answer

Harmonic distortion

Answer

Voltage stability

Question 40

A benefit of centralized economic dispatch is:

Accepted Answer

Improved system-wide efficiency and reliability

Answer

Lower operating costs for individual generators

Answer

Reduced need for transmission infrastructure

Question 41

**Objective Function of Economic Dispatch (ED):** What is the primary goal of ED?

Accepted Answer

Minimize the total cost of fuel required for power generation

Answer

Maximize the power output of individual generators

Answer

Ensure reliable and stable power supply

Question 42

**Meaning of Incremental Fuel Cost:** What does incremental fuel cost represent?

Accepted Answer

The change in fuel cost resulting from a change in power output

Answer

The cost of fuel per unit of energy produced

Answer

The fixed cost of operating a power plant

Question 43

**Unit Commitment Problem:** What is the essence of the unit commitment problem in ED?

Accepted Answer

Determining which generators to operate and at what power levels to meet demand while considering start-up and shut-down costs

Answer

Calculating the optimal fuel mix for power generation

Answer

Scheduling the power flow through transmission lines

Question 44

**Role of Coordination Equations:** What is the purpose of coordination equations in ED?

Accepted Answer

To ensure that the scheduled power outputs of generators collectively meet the total system demand

Answer

To minimize power losses in the system

Answer

To prevent overloading of transmission lines

Question 45

**Advantages of ED:** Which of the following is a primary benefit of implementing ED?

Accepted Answer

Reduced operating costs through optimized fuel consumption

Answer

Enhanced power system stability

Answer

Reduced environmental impact

Answer

Improved voltage regulation

Question 46

What is the primary objective of economic dispatch in power systems?

Accepted Answer

To achieve minimum operating costs while meeting electricity demand

Answer

To maximize power generation output

Answer

To improve system reliability

Question 47

At what time frame is economic dispatch typically performed?

Accepted Answer

Hourly or sub-hourly

Answer

Daily

Answer

Monthly

Answer

Weekly

Question 48

Which of the following costs is NOT included in the economic dispatch formulation?

Accepted Answer

Capital investments

Answer

Maintenance costs

Answer

Fuel expenses

Answer

Emission penalties

Question 49

What is the role of the incremental cost curve in economic dispatch?

Accepted Answer

It determines the optimal operating point of each generator

Answer

It forecasts future electricity demand

Answer

It represents the total generation cost

Question 50

What is the purpose of load forecasting in economic dispatch?

Accepted Answer

To predict electricity demand for optimal scheduling

Answer

To calculate transmission losses

Answer

To mitigate environmental concerns

Answer

To determine transmission capacity

Question 51

Which of the following optimization methods is suitable for solving the economic dispatch problem?

Accepted Answer

Lagrange Multipliers or Linear Programming

Answer

Dynamic Programming only

Answer

None of the above

Answer

Genetic Algorithms only

Question 52

What is the economic significance of optimizing power flow in economic dispatch?

Accepted Answer

It minimizes the cost of supplying electricity while meeting demand

Answer

It reduces power losses in the grid

Answer

It enhances voltage stability