“Research of the quality indicators of the simplified automatic regulation system of a mini-HPP”

Abstract

The article provides a study of regulation quality indicators for both complete and simplified
mathematical model of a mini-HPP hydro unit. The relevance of further optimizing the automation
schemes and structures of the mini-HPP under remote control conditions (without service
personnel) is demonstrated. A mathematical model of the automated control system has been
developed, reflecting the existing structure and based on the MATLAB system for engineering and
scientific calculations. The general structural diagram of the control system, without analysis of its
structural forms, was used as a basis for modeling transient processes and analyzing the operation of mini-HPP units. The model for studying the characteristics of the hydraulic unit is based on a circuit
with a reversible connection. Elements of the model are presented in the form of transfer functions.
A comparative simulation of a simplified system and a system containing all connections was
performed. For both schemes, parameters of transient processes in terms of rotation frequency and
torque were obtained. It is shown that the transient time is longer for the simplified system due to
the oscillating transient, but the frequency overshoot is the same for both types of models for any
type of transients (start-up, loading, and unloading). It is demonstrated that modeling without
restrictions does not have practical significance and is informative in nature, highlighting the need
for introducing restrictions. A comparative study of models with different values of the unit's time
constant was conducted, showing that overregulation increases for models with a smaller time
constant, but the duration of the transition process remains almost the same. It is proven that the
regulation system with a simplified model is generally stable but provides transient processes with
oscillations and can be used if high-quality regulation is not required.