Multidimensional Parallel Dynamic Programming Algorithm Based on Spark for Large-Scale Hydropower Systems
- PDF / 2,734,986 Bytes
- 18 Pages / 439.37 x 666.142 pts Page_size
- 36 Downloads / 201 Views
Multidimensional Parallel Dynamic Programming Algorithm Based on Spark for Large-Scale Hydropower Systems Yufei Ma 1 & Ping-an Zhong 1 & Bin Xu 1,2
1
1
& Feilin Zhu & Yao Xiao & Qingwen Lu
1
Received: 21 November 2019 / Accepted: 17 May 2020/ # Springer Nature B.V. 2020
Abstract
The “curse of dimensionality” is a major problem in dynamic programming (DP) algorithms for large-scale hydropower systems. This study proposes a parallel DP algorithm based on Spark (PDPoS) to alleviate the “curse of dimensionality”. Parallel computing experiments are formulated by varying the number of reservoirs, the number of discrete water levels and the number of CPU cores to analyze the quality and efficiency of PDPoS. The methodologies were applied to a cascade reservoir system made up of eight reservoirs in the Yuanshui River Basin in China. The results are as follows. (1) The number of discrete water levels is the dominant factor in the solution quality, while the number of reservoirs is the dominant factor in the solving efficiency. (2) The runtime of PDPoS is markedly affected by the calculational scale (determined by the number of reservoirs and discrete water levels), and the relationship between the number of CPU cores and the runtime is triphasic with increasing calculational scale. (3) The larger the calculational scale is, the better the parallel performance (i.e., the parallel speedup and parallel efficiency). The proposed PDPoS method has strong generality, high parallel performance, and high practical value. Keywords Hydropower operation . Curse of dimensionality . Multidimensional dynamic programming . Parallel computing . Spark
* Ping-an Zhong [email protected] * Bin Xu [email protected]
1
College of Hydrology and Water Resources, Hohai University, NO 1, Xikang Road, Nanjing 210098, China
2
State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, No. 223, Guangzhou Road, Nanjing 210029, China
Ma Y. et al.
1 Introduction With the rapid growth of reservoir operations in China over the past several decades, the optimal operation of a high-dimensional cascade hydropower system has become a main way to efficiently utilize water energy resources (Xu et al. 2019). However, the operation of a highdimensional hydropower system is an optimization problem of multivariable coupling and complex systems. This problem has the characteristics of high dimensionality, complex associations and multiple objectives (Labadie 2004). It is necessary to consider the hydrological, hydraulic and electric connections between upstream and downstream reservoirs as well as the large number of constraints. With the expansion of hydropower scales, the need for refined management is constantly increasing. Therefore, hydropower management faces intensified challenges from improving the solution quality and solving efficiency of the medium- and long-term optimal operation of a hydropower system (Ehteram et al. 2018; Xu et al. 2015). At present, dynamic programming (DP), its imp
Data Loading...
