Distributionally Robust Multiperiod Dispatch Optimization with Uncertainty Modeling for Renewable Generation and Distributed Energy Resources

Core Concepts

The core message of this article is to propose a novel approximation method for multiple joint chance constraints (JCCs) to model the uncertainty in power system dispatch problems, which solves the conservativeness and potential infeasibility concerns of the conventional Conditional Value at Risk (CVaR) method. The proposed method is then extended to handle multiple data-driven distributionally robust joint chance constraints (DRJCCs) that fit the practical scenario of power system dispatch problems where the distribution of uncertain variables is often inaccessible.

Abstract

The article presents a multiperiod dispatch optimization model for integrated transmission and distribution networks, including uncertainties from both renewable generations and flexibilities provided by active distribution networks (ADNs). The key highlights and insights are:

The authors propose a novel approximation method for handling multiple joint chance constraints (JCCs) in the dispatch problem. This method solves the over-conservativeness and potential infeasibility issues of the conventional CVaR approximation by using an alternating optimization approach.

The proposed JCC approximation method is further extended to handle multiple data-driven distributionally robust joint chance constraints (DRJCCs), which is more suitable for practical power system applications where the true distribution of uncertain variables is unknown.

The dispatch model considers uncertainties in both renewable generation and the flexibilities of ADNs, which are modeled as multiple DRJCCs with different risk levels assigned to different system components (generators, ADNs, transmission lines).

The asymmetrical modeling of participation factors and reserves is proposed, where ADNs only provide up-reserves to enable a more economically efficient dispatch result.

Numerical simulations on small examples and IEEE test cases demonstrate the superiority and practicality of the proposed uncertainty modeling and approximation method compared to the conventional CVaR approach.

Stats

The article does not provide any explicit numerical data or statistics. The key figures and metrics are:

The number of time slots T in the multiperiod dispatch problem
The number of buses I, branches L, ADNs D, conventional generators G, and renewables W in the power system
The risk budgets ϵg, ϵd, ϵl for generators, ADNs, and transmission lines, respectively
The Wasserstein radii ρg, ρd, ρl for the DRJCC ambiguity sets of generators, ADNs, and transmission lines, respectively

Quotes

There are no direct quotes from the content that are particularly striking or support the key arguments.

Key Insights Distilled From

Multiple Joint Chance Constraints Approximation for Uncertainty Modeling in Dispatch Problems

by Yilin Wen,Yi... at arxiv.org 04-02-2024

https://arxiv.org/pdf/2404.01167.pdf

Deeper Inquiries

How can the proposed approximation method be extended to handle other types of uncertainty modeling, such as robust optimization or stochastic programming, beyond the chance-constrained programming framework

The proposed approximation method can be extended to handle other types of uncertainty modeling by adapting the formulation to fit the specific requirements of robust optimization or stochastic programming.
For robust optimization, the method can be modified to incorporate robust constraints that ensure the feasibility of the solution under a set of worst-case scenarios. This would involve adjusting the constraints to account for the uncertainty set and the level of robustness desired in the optimization problem. By formulating the constraints to account for a range of possible scenarios, the optimization model can provide solutions that are resilient to variations in the uncertain parameters.
In the case of stochastic programming, the method can be adapted to include probabilistic constraints that capture the uncertainty in the parameters. By introducing probabilistic constraints based on the probability distribution of the uncertain variables, the optimization model can account for the stochastic nature of the problem and provide solutions that are robust against variations in the uncertain parameters.
Overall, by tailoring the proposed approximation method to the specific requirements of robust optimization or stochastic programming, it can effectively handle different types of uncertainty modeling beyond the chance-constrained programming framework.

What are the potential drawbacks or limitations of the asymmetrical modeling of participation factors and reserves, and under what circumstances would a symmetrical modeling be more appropriate

The asymmetrical modeling of participation factors and reserves in the dispatch optimization model may have potential drawbacks or limitations in certain scenarios. One drawback is that it may lead to a suboptimal allocation of reserves between generators and ADNs. If the reserve requirements of the system are not adequately balanced between up-reserves and down-reserves, it could result in inefficiencies in the dispatch strategy.
Additionally, asymmetrical modeling may introduce complexity in the optimization model, especially when coordinating the actions of generators and ADNs to ensure system reliability and stability. The asymmetrical modeling approach may require additional coordination mechanisms to manage the interaction between different types of resources effectively.
Under circumstances where a symmetrical modeling approach would be more appropriate, it is when the reserve requirements of the system can be equally distributed between generators and ADNs. In cases where both types of resources have comparable capabilities to provide reserves, a symmetrical modeling approach can ensure a more balanced and efficient allocation of reserves across the system.
Ultimately, the choice between asymmetrical and symmetrical modeling of participation factors and reserves should be based on the specific characteristics of the power system, the capabilities of the resources, and the desired operational objectives.

How can the proposed dispatch optimization model be integrated with real-time market operations and control mechanisms to ensure reliable and economical power system operations in the presence of uncertainties

Integrating the proposed dispatch optimization model with real-time market operations and control mechanisms is crucial for ensuring reliable and economical power system operations in the presence of uncertainties. This integration can be achieved through a coordinated approach that leverages real-time data, market signals, and control signals to make informed decisions in response to changing system conditions.
One way to integrate the dispatch optimization model with real-time operations is through a closed-loop control system that continuously monitors the system state, updates the optimization model with real-time data, and adjusts the dispatch decisions based on the current conditions. By incorporating feedback mechanisms that capture the real-time performance of the system, the dispatch model can adapt to uncertainties and disturbances in the system, ensuring reliable and efficient operation.
Furthermore, the integration with real-time market operations involves considering market prices, demand response signals, and other market signals to optimize the dispatch decisions in a way that maximizes economic efficiency while meeting operational constraints. By incorporating market dynamics into the optimization model, the system can respond to price signals and market conditions to make cost-effective dispatch decisions.
Overall, the integration of the dispatch optimization model with real-time market operations and control mechanisms requires a holistic approach that considers the dynamic nature of the power system, the uncertainties present, and the need for reliable and economical operation. By leveraging real-time data and market signals, the system can optimize its dispatch decisions in a way that balances reliability, efficiency, and cost-effectiveness.