Load Match-Oriented Coordinated Control for Modular High Temperature Gas-Cooled Reactor Based on Dynamic Matrix Control

To cope with the flexibility from both load side and supply side, nuclear power generation should provide flexible operation services to improve its economic competitiveness. The prerequisite of flexible operation is the real-time realization of the operation point which is usually achieved by unit coordinated control finding the setpoints of nuclear power, coolant flow and feedwater flow to meet various load demand and keep key parameters within reasonable limits. Modular high temperature gas-cooled reactor (MHTGR) is typically a small reactor and adopt adjustable helium flow, graphite and once through steam generator (OTSG) as coolant, moderator, heat exchanger, respectively. The thermal hydraulic characteristics of MHTGR are of significant difference compared with that of pressurized water reactor (PWR). As a result, the coordinated control design for MHTGR plant is quite different from the PWR. In this paper, the feedwater flow and control rods are solely used to regulate the steam temperature and nuclear power, respectively. Moreover, the so-called dynamic matrix control (DMC) then is utilized to realize the load match for MHTGR thermal power, where the setpoint of helium flow is regarded as manipulated variables and the modular thermal power is regarded as controlled variables to be optimized. The effectiveness of the proposed method is then tested and verified by a hardware-in-loop simulation through a commercial distributed control system (DCS).

Dynamic multi-objective matrix control for a class of switched systems

This article focuses on the tracking and stabilizing issues of a class of discrete switched systems. These systems are characterized by unknown switching sequences, a non-minimum phase, and time-varying or dead modes. In particular, for those governed by an indeterminate switching signal, it is very complicated to synthesize a control law able to systematically approach general reference-tracking difficulties. Taking into account the difficulty to express the dynamic of this class of systems, the present paper presents a new Dynamic matrix control method based on the multi-objective optimization and the truncated impulse response model. The formulation of the optimization problem aims to approach the general step-tracking issues under persistent and indeterminate mode changes and to overcome the stability problem along with retaining as many desirable features of the standard dynamic matrix control (DMC) method as possible. In addition, the formulated optimization problem integrates estimator variables able to manipulate the optimization procedure in favor of the active mode with an appropriate adjustment. It also provides a progressive and smooth multi-objective control law even in the presence of problems whether in subsystems or switching sequences. Finally, simulation examples and comparison tests are conducted to illustrate the potentiality and effectiveness of the developed method.

Controle Dinâmico de Matriz aplicado a Inversores Fonte de Tensão

O presente trabalho aborda a implementação do algoritmo de controle Dynamic Matrix Control (DMC) em um inversor fonte de tensão monofásico para a obtenção de uma corrente senoidal controlada na carga. A validação do controle é feita por meio do esquema Controller Hardware-In-the-Loop (CHIL), em que o sistema é modelado pelo simulador em tempo real Typhoon HIL e controlado pelo microcontrolador RCP dSPACE. Os resultados obtidos neste artigo validam o controle proposto.

Networked control system time-delay compensation based on PI-based dynamic matrix control

The network-induced time-delay caused by the introduction of the communication network in a networked control system has a great negative impact on the stability and performance of the system. In order to compensate for the performance degradation of the networked control system caused by time-delay, a time-delay compensation method based on PI-based dynamic matrix control for networked control system is proposed. In this study, autoregressive integrated moving average model is used to predict the future time-delay. The predictive time-delay replaces the actual time-delay as a parameter of the controller. In order to improve the compensation effect of dynamic matrix control, the feedback structure of the PI control and the predictive ability of dynamic matrix control are combined. The new objective function of dynamic matrix control is combined with PI structure to obtain the optimal control increment value. The PI controller can correct the output of dynamic matrix control and reduce the deviation between the actual output and the predicted output. The effect of the model mismatch and interference on the system is reduced. The robustness and anti-interference performance of the system is improved. The controller can select the appropriate control value to transmit to the actuator to compensate for the effect of the random time-delay in the networked control system. The stability of the compensation method is proved. Through the simulation results, the effectiveness of the proposed time-delay compensation method is verified.

Dynamic matrix control with input saturation constrained

It is proposed, in this paper a dynamic matrix control (DMC) with an anti-windup (AW) based on linear matrix inequalities (LMI). The DMC-AW control is applied in the ballbeam system, in which the main purpose is to control the ball position on a rotating beam. System modeling was performed, which presented two degrees of freedom. For the mechanical system implementation a microcontroller, an ultrasonic sensor, and a servo motor were used. Theproposed control was implemented both numerically with the software MATLAB and with the microcontroller ATmega328Pu. The simulation results validated the eciency of the proposed DMC-AW and showed that the approach improves the response of the system under input saturation.