Kaipeng Xu

Kaipeng Xu, Zhuo Zhi, Keyue Jiang

Coordinating large-scale, heterogeneous building aggregations for demand response (DR) is impeded by a dual challenge: the computational intractability of centralized Model Predictive Control (MPC) and the inadequacy of conventional feature selection methods, which fail to address the error-compounding nature of multi-step forecasting required by MPC. This paper proposes a comprehensive, data-driven framework that first employs a systematic, MPC-aware feature selection methodology to ensure robust multi-step prediction, then models the complex building dynamics using a novel Input-Convex Encoder-Only Transformer (IC-EoT) to guarantee a convex optimization problem, and finally solves the resulting constraint-coupled problem (CCP) in a fully distributed manner using the Tracking Alternating Direction Method of Multipliers (ADMM) algorithm. The framework is validated in a high-fidelity co-simulation environment, controlling a heterogeneous aggregation of consumer and prosumer buildings based on the EnergyPlus under a dynamic time-of-use (TOU) tariff. Results demonstrate that the proposed distributed approach achieves near-identical economic optimality and superior thermal comfort compared to a theoretical centralized controller, while exhibiting exceptional computational scalability that overcomes the real-time infeasibility of the centralized approach for large aggregations.

Kaipeng Xu, Zhuo Zhi, Keyue Jiang

Learning-based Model Predictive Control (MPC) has emerged as a powerful strategy for building demand response. However, its practical deployment is often hindered by the non-convex optimization problems induced by standard neural network models. These problems lead to long solver times and suboptimal solutions, making real-time control over long horizons challenging. While Input Convex Neural Networks (ICNNs), such as Input-Convex Long Short-Term Memorys (IC-LSTMs), are developed to address the convexity issue, their recurrent architectures suffer from high computational cost and gradient instability as the prediction horizon increases. To overcome these limitations, this paper introduces the Input-Convex Encoder-only Transformer (IC-EoT), a novel architecture that synergizes the parallel processing capabilities of the Transformer with the guaranteed tractability of input convexity. The IC-EoT was developed and evaluated in a high-fidelity co-simulation framework using the Energym Python library to interface with the EnergyPlus building simulator, and compared against its recurrent convex counterpart (IC-LSTM) and standard non-convex models. The results demonstrate that the IC-EoT is structurally immune to the gradient instability that affects recurrent ICNNs while maintaining comparable predictive accuracy. More critically, it substantially reduces MPC solver times; this speed advantage grows with the prediction horizon, with the IC-EoT proving 2.7 to 8.3 times faster than the IC-LSTM across horizons spanning from one to eight hours. This leap in computational efficiency makes the IC-EoT a robust and practical solution, enabling effective, real-time MPC for building energy management under realistic horizon decision-making scenarios.

Kaipeng Xu, Zhuo Zhi, Ruixuan Zhao et al.

The high energy consumption of buildings presents a critical need for advanced control strategies like Demand Response (DR). Differentiable Predictive Control (DPC) has emerged as a promising method for learning explicit control policies, yet conventional DPC frameworks are hindered by three key limitations: the use of simplistic dynamics models with limited expressiveness, a decoupled training paradigm that fails to optimize for closed-loop performance, and a lack of practical safety guarantees under realistic assumptions. To address these shortcomings, this paper proposes a novel End-to-End Differentiable Predictive Control (E2E-DPC) framework. Our approach utilizes an Encoder-Only Transformer to model the complex system dynamics and employs a unified, performance-oriented loss to jointly train the model and the control policy. Crucially, we introduce an online tube-based constraint tightening method that provides theoretical guarantees for recursive feasibility and constraint satisfaction without requiring complex offline computation of terminal sets. The framework is validated in a high-fidelity EnergyPlus simulation, controlling a multi-zone building for a DR task. The results demonstrate that the proposed method with guarantees achieves near-perfect constraint satisfaction - a reduction of over 99% in violations compared to the baseline - at the cost of only a minor increase in electricity expenditure. This work provides a deployable, performance-driven control solution for building energy management and establishes a new pathway for developing verifiable learning-based control systems under milder assumptions.