Distributed Real-Time Power Balancing in Renewable-Integrated Power Grids With Storage and Flexible Loads

Abstract

Abstract-The large-scale integration of renewable generation directly affects the reliability of power grids. We investigate the problem of power balancing in a general renewable-integrated power grid with storage and flexible loads. We consider a power grid that is supplied by one conventional generator (CG) and multiple renewable generators (RGs) each co-located with storage, and is connected with external markets. An aggregator operates the power grid to maintain power balance between supply and demand. Aiming at minimizing the long-term system cost, we first propose a real-time centralized power balancing solution, taking into account the uncertainty of the renewable generation, loads, and energy prices. We then provide a distributed implementation algorithm, significantly reducing both computational burden and communication overhead. We demonstrate that our proposed algorithm is asymptotically optimal as the storage capacity increases and the CG ramping constraint loosens. Moreover, the distributed implementation enjoys a fast convergence rate, and enables each RG and the aggregator to make their own decisions. Simulation shows that our proposed algorithm outperforms alternatives and can achieve near-optimal performance for a wide range of storage capacity.

Understanding the CDSA of poly(lactide) containing triblock copolymers

“…In our previous studies, we have shown that PLLA-containing block copolymers can be fabricated using a combination of reversible addition-fragmentation chain transfer (RAFT) and ring-opening polymerisation (ROP), where we have been able to achieve tuneable cylindrical micelles with a range of coronal blocks by CDSA. [27][28][29] Further work was carried out to enrich the functionality of the PLLA-based cylinders 30,31 and successfully realize stereocomplexation-triggered morphological transitions, 32 indicating the promising future of these cylindrical particles in the biomedical realm. Similar to conventional phase separation-driven assembly, it can be expected that triblock copolymers will lead to an alternate morphology when undergoing CDSA as a consequence of the extra coil phase.…”

Residential Energy Storage Management With Bidirectional Energy Control

“…Energy storage has been considered at the power grid operator or aggregator to combat the fluctuation of renewable generation, with many works in literature on storage control and assessment of its role in renewable generation [2], for power balancing with fixed load [3], [4] or flexible load control [6], [7], and for phase balancing [5]. Residential energy storage systems to reduce electricity cost have been considered without renewable [17] and with renewable integration [10]- [13], [18]- [24].…”

“…To minimize the objective of P4 b , one possible solution is to minimize E w t and maximize F w s,t . Due to constraint (6), S w c,t · F w s,t = 0 must be satisfied. Thus, we have two conditions: i) If F w s,t ≥ 0 and S w c,t = 0, it means the remaining amount S t − S w,t , if any, will be only sold back to the grid.…”

Impacts of Ramping Inflexibility of Conventional Generators on Strategic Operation of Energy Storage Facilities

“…The work in [6] investigates the reduction in different conventional generators' ramping activity by increasing ramping capability of storage systems. In [7], it is concluded that larger storage facilities lead to less ramping constraints and thus, reduction of the total system cost. In [8], dispatching storage systems to mitigate forecast errors of wind power production is discussed considering the ramping capabilities of storage facilities.…”