Synergetic Control Strategy for Water Hammer Wave and Mass Wave in Hydropower Station With Downstream Channel

Abstract

This paper investigates the synergetic control strategy for water hammer wave and mass wave in hydropower station with downstream channel. Firstly, the mathematical model of hydropower station with downstream channel (HSDC) and hydropower station with downstream channel and surge tank (HSDCST) are established. Then, the controller formula of HSDC and HSDCST are derived on the basis of the synergetic theory. Furthermore, it is parsed that the dynamic characteristics of HSDC and HSDCST to various disturbances under synergetic control strategy. Finally, the robustness and applicability of synergetic control strategy for HSDC and HSDCST are analyzed. The results indicate that the macro variable is the linear combination of state variables and their derivatives based on feedback linearization of the state equation. For the hydropower station under the synergetic control strategy, it has excellent dynamic characteristics employing sensitive response, small overshoot, fast attenuation speed and no static error. The synergetic control strategy is superior to the PID control strategy under various disturbances in controlling the amplitude of water hammer wave in HSDC, which is down 12.5%. The attenuation of mass wave in HSDCST under synergetic control strategy is faster, and the settling time is 6.16s less than that of PID control strategy. The synergetic control strategy is superior to the PID control strategy under various disturbances in controlling the amplitude of water hammer wave in HSDC and the attenuation of mass wave in HSDCST. Compared with PID control strategy, it is the robustness of synergetic control strategy that are much more advantageous for HSDC and HSDCST. Specifically, RI value is about 1.65, 0.18 for HSDC and 2.21, 0.25 for HSDCST under synergetic control strategy, while it is about 3.05, 1.20 and 3.32, 1.30 under PID control strategy. Moreover, the synergetic control strategy has a wide applicability in controlling the water hammer wave in HSDC and mass wave in HSDCST.

Models for a hydropower plant: a review

“…Ardul Munoz, M. Petrous and J. Dewi Ieuan, 2013;Li et al, 2016;K. Nabd and A. Jesus Fraile, 2017;Guo and Yang, 2018;Cassano et al, 2021;Reigstad Tor Inge, 2021;Zhang et al, 2022). Also, multiple penstocks supplied from a common water column are modelled just based on the flow in the upper manifold to be equal to the flow in each penstock and the governing principles remain the same (de Mello et al, 1992;H.…”

“…Ardul Munoz, M. Petrous and J. Dewi Ieuan, 2013). Based on water hammer consideration in penstock modelling as described in (de Mello et al, 1992; P. Kundur, 2009; H. Ardul Munoz, M. Petrous and J. Dewi Ieuan, 2013; K. Nabd and A. Jesus Fraile, 2017;Cassano et al, 2021;Zhang et al, 2022), the hydropower models are classified as the ones with 'elastic water column models' and 'inelastic water column models' which have significant differences in dynamic the response of hydropower plants. One more significant component in the upstream flow region is the surge tank which is proven to be of utmost importance while studying the dynamic behaviour of hydropower plants.…”

“…The models implementing robust control, most preferably the ones with time-domain dynamic representation have been worked upon very less. Though some time-domain models for synergetic control studies and state space models of hydropower and (Pump Storage Hydropower) PSH have been explored in (Zhang et al, 2022) and (Dong et al, 2020), transient studies for grid side have been studied more than for the generator side. With the concern for reliable and resilient power system, the control for hydropower must be adequate from all the possible aspects.…”