Virtual power plants (VPPs) are becoming a cornerstone of future grids, aggregating distributed PV, wind, storage, and flexible loads for market participation and real-time balancing. As operations move to minute-- and second--level feedback, communication security shifts from a compliance item to an operational constraint: latency, reliability, and confidentiality jointly determine whether dispatch, protection, and settlement signals arrive on time. Conventional PKI and key-rotation schemes struggle with cross-domain, high-frequency messaging and face long-term quantum threats. Quantum key distribution (QKD) offers information-theoretic key freshness, but its key yield is scarce and stochastic, often misaligned with bursty VPP traffic. This paper proposes a key-aware priority and quota framework that treats quantum keys as first-class scheduling resources. The design combines (i) forecast-driven long-term quotas and short-term tokens, (ii) key-aware deficit-round-robin arbitration, (iii) a preemptive emergency key reserve, and (iv) graceful degradation via encryption-mode switching and controlled down-sampling for non-critical traffic. A drift-plus-penalty analysis establishes strong stability under average supply--demand balance with quantifiable bounds on backlog and tail latency, providing interpretable operating guarantees. We build a reproducible testbed on IEEE 33- and 123-bus VPP systems and evaluate normal, degraded, and outage regimes with industry-consistent message classes and TTLs. Against FIFO, fixed-priority, and static-quota baselines, the proposed scheme consistently reduces tail delay and passive timeouts for critical messages, improves per-bit key utility, and enhances power-tracking reliability during key scarcity and regime switches.
Virtual power plants (VPPs) are becoming a cornerstone of future grids, aggregating distributed PV, wind, storage, and flexible loads for market participation and real-time balancing. As operations move to minute-- and second--level feedback, communication security shifts from a compliance item to an operational constraint: latency, reliability, and confidentiality jointly determine whether dispatch, protection, and settlement signals arrive on time. Conventional PKI and key-rotation schemes struggle with cross-domain, high-frequency messaging and face long-term quantum threats. Quantum key distribution (QKD) offers information-theoretic key freshness, but its key yield is scarce and stochastic, often misaligned with bursty VPP traffic. This paper proposes a key-aware priority and quota framework that treats quantum keys as first-class scheduling resources. The design combines (i) forecast-driven long-term quotas and short-term tokens, (ii) key-aware deficit-round-robin arbitration, (iii) a preemptive emergency key reserve, and (iv) graceful degradation via encryption-mode switching and controlled down-sampling for non-critical traffic. A drift-plus-penalty analysis establishes strong stability under average supply--demand balance with quantifiable bounds on backlog and tail latency, providing interpretable operating guarantees. We build a reproducible testbed on IEEE 33- and 123-bus VPP systems and evaluate normal, degraded, and outage regimes with industry-consistent message classes and TTLs. Against FIFO, fixed-priority, and static-quota baselines, the proposed scheme consistently reduces tail delay and passive timeouts for critical messages, improves per-bit key utility, and enhances power-tracking reliability during key scarcity and regime switches.
The proliferation of distributed energy resources (DERs) and demand-side flexibility has made virtual power plants (VPPs) central to modern grid operation. Yet their end-to-end business pipeline, covering bidding, dispatch, metering, settlement, and archival, forms a tightly coupled cyber-physical-economic system where secure and timely communication is critical. Under the combined stress of sophisticated cyberattacks and extreme weather shocks, conventional cryptography offers limited long-term protection. Quantum key distribution (QKD), with information-theoretic guarantees, is viewed as a gold standard for securing critical infrastructures. However, limited key generation rates, routing capacity, and system overhead render key allocation a pressing challenge: scarce quantum keys must be scheduled across heterogeneous processes to minimize residual risk while maintaining latency guarantees. This paper introduces a quantum-authenticated aggregation and settlement framework for VPPs. We first develop a system-threat model that connects QKD key generation and routing with business-layer security strategies, authentication strength, refresh frequency, and delay constraints. Building on this, we formulate a key-budgeted risk minimization problem that jointly accounts for economic risk, service-level violations, and key-budget feasibility, and reveal a threshold property linking marginal security value to shadow prices. Case studies on a representative VPP system demonstrate that the proposed approach significantly reduces residual risk and SLA violations, enhances key efficiency and robustness, and aligns observed dynamics with the theoretical shadow price mechanism.
This study proposes a lightweight industrial control protocol based on quantum key distribution (QKD) to enhance security and optimize performance in resource-constrained industrial control systems (ICS). Unlike traditional QKD schemes, primarily optimized for long-distance communication in ideal IT environments, this work introduces a resource-aware QKD architecture tailored explicitly for short-range industrial control networks with constrained computing/storage/bandwidth. The protocol constructs a multi-layered stack—integrating the physical layer, quantum key management layer, data link layer, network layer, and application layer—to enable secure quantum key generation, efficient distribution, and dynamic utilization, while avoiding excessive resource overhead on embedded ICS devices. Furthermore, three key optimization strategies are introduced: (1) resource optimization adopts AES-128 with FPGA acceleration, reducing encryption overhead from 15% to 20% CPU utilization to 3%–5% (validated in Sec. V A); (2) real-time assurance implements deficit-round-robin frame scheduling, guaranteeing <2.5 ms latency for safety-critical commands; and (3) stability enhancement utilizes dual-QKD-link redundancy with 5–8 s failover, improving MTBF from 3000 to 10 000+ h. The security real-time trade-off is quantified via coefficient B = Slevel/(Ddelay × δ) (detailed in Sec. V B), where Slevel ∈ [1,10] represents encryption strength, Ddelay is measured latency, and δ is CPU load. Experimental results show that the balance coefficient B improves from 2.1 ± 0.4 (Modbus) to 5.2 ± 0.6, confirming superior balance. This work provides a feasible technical pathway for securing critical infrastructure in the quantum era. Experiments demonstrate a 75% reduction in computational overhead and a real-time-security balance coefficient of 4.5–6.0, which is higher than that of Modbus and PROFINET.
The accelerating digitalization and decentralization of modern power systems expose critical communication infrastructures to escalating cyber risks, particularly under emerging quantum computing threats. This paper presents an integrated techno-economic framework to evaluate the feasibility of Quantum Key Distribution (QKD) for secure power-system communications. A stochastic system model is developed to jointly capture time-varying key demand, QKD supply under optical-loss constraints, station-side buffering, and post-quantum cryptography (PQC) fallback mechanisms. Analytical conditions are derived for service-level assurance, including buffer stability, outage probability, and availability bounds. Building on this, two quantitative metrics, including the Levelized Cost of Security (LCoSec) and Cost of Incremental Security (CIS), are formulated to unify capital, operational, and risk-related expenditures within a discounted net-present-value framework. Using IEEE 118-bus, 123-node, and 39-bus test systems, we conduct discrete-event simulations comparing PQC-only, QKD-only, and Hybrid architectures across multiple topologies and service profiles. Results show that Hybrid architectures dominated by QKD significantly reduce key-outage probability and SLA shortfalls, achieving near-unit availability for real-time and confidentiality-critical services. Economic analyses reveal clear breakeven zones where QKD-enhanced deployments become cost-effective, primarily in metropolitan and distribution-level networks under moderate optical loss and buffer sizing. The proposed framework provides a reproducible, risk-aware decision tool for guiding large-scale, economically justified QKD adoption in future resilient power-system infrastructures.
To address growing cybersecurity challenges in modern power dispatch systems, this paper proposes a multi-layer modeling and optimization framework for SCADA systems enhanced with quantum key distribution (QKD). While most existing applications of QKD in the power sector focus on building secure point-to-point communication tunnels, they rarely consider the system-level coupling between key dynamics and control scheduling. In contrast, our approach integrates quantum key generation, consumption, inventory prediction, and control latency into a unified model, enabling key-aware reconfiguration of SCADA control chains based on task security demands and real-time resource constraints. To resolve conflicts in key resource allocation between transmission system operators (TSOs) and distribution system operators (DSOs), we formulate a bi-level Stackelberg game and transform it into a mathematical program with complementarity constraints (MPCC). We further develop an efficient Level Decomposition-Complementarity Pruning (LD-CP) algorithm to solve the problem. To support reproducible evaluation, we build an end-to-end co-simulation platform that integrates physical-layer disruptions via OpenQKD-Sim, Q3P/IEC-104 protocol stack binding, and real-time control-chain monitoring through Grafana. Experimental results on the IEEE 39- and 118-bus systems show that our method increases task success rate by 25%, reduces peak frequency deviation by 70%, and improves key utilization to 83%. This work lays the foundation for future quantum-secure control systems in power grid operations.
Low-voltage communication systems in next-generation data transmission networks connect smart meters, feeder controllers, EV chargers, and distributed energy resources; however, the dense topological structure they have and the limited abilities of their endpoints make the direct deployment on quantum hardware be not practical. In order to solve this restriction, this article puts forward a Hybrid Quantum Encryption Scheme for Low-Voltage Systems (HQES-LV), which keeps quantum key distribution on backbone and gateway layers, uses a post-quantum authenticated control plane, and gives lightweight session protection to edge devices by means of risk-adaptive key renewal. A literature-calibrated digital twin is constructed to simulate mixed control, telemetry, and maintenance traffic, along with replay attacks, man-in-the-middle probing, quantum channel degradation, and gateway outages. Result data indicate that in the pressure condition, the HQES-LV can cut control waiting time down to 6.1 ms, hold the possibility of secret information leakage to 0.4%, and make the time of getting back to normal shorter to 6.7 s. Under a 1.2 p.u. load, it maintains 7.3 ms latency and 98.4% session establishment success. When QBER rises to 5.5%, the proposed scheme still preserves 58.9% effective key availability and 96.7% packet delivery. These findings indicate that practical quantum security for low-voltage systems should be realized through hierarchical orchestration rather than endpoint quantumization, and that the combination of QKD backbone supply, post-quantum fallback, and the adaptive session arrangement can provide a path that is more ready for deployment for future electric power communication networks.
Power-system operations generate large volumes of sensitive operational data - including real-time telemetry, protection control signals, metering and settlement records, and maintenance logs - which are subject to strict confidentiality, integrity, and availability requirements. Highly sensitive data must be retained long term for regulatory compliance and dispute forensics, imposing elevated requirements on cryptographic strength, key management, and auditability. This paper presents an end-to-end, quantum-key-based data protection framework tailored for power-grid operations. The design leverages QKD as a high-entropy root key source and integrates a lifecycleaware Key Management System (KMS), controlled offline key injection with tamper-resistant secure media, hardware-backed cryptographic modules at terminals and gateways, a rule-driven field-level encryption engine with triggerable re-encryption, and an immutable audit chain for verifiable logging. The architecture enforces strong authentication, integrity verification, and comprehensive auditability across the full key and data lifecy-cle-generation, injection, loading, use, backup, re-encryption and destruction-while enabling transparent gateway-mediated access for legacy applications. Practical deployment trade-offs, alternatives (TEE/MPC, PQC hybrids), and anchoring strategies for long-term forensic evidence are discussed, yielding a modular, scalable, and quantum-resistant solution for protecting highsensitivity power-system data.