Reset Control Research Articles

OPTIMALISASI HMI SCADA UNTUK MONITORING DAN KONTROL REPEATER RADIO KOMUNIKASI MENGGUNAKAN MODEM GPRS INTEK J65i-X

Al Anamila Nur Aufa, Teguh Yuwono, in paper SCADA HMI optimization for monitoring and control repeater using radio communication modem GPRS INTEK J65i–X explain that radio communications at PT PLN ( Persero ) APD Central Java and Yogyakarta is still a major communication medium for coordinating the work , both maintenance and handling of interference between units . Repeaters in this case an important role in the communication process between APD dispatcher JTY with Area - Area and officers in the field because of the presence of the communication range of the repeater spacing becomes wider . In operation repeaters can be susceptible to interference that can result in radio communications in the areas covered by the repeater to be disrupted so that the communication between the dispatcher APD JTY with Area - Area and field workers to be blocked. Handling repeater for this disorder is not maximized due to the lack of real time monitoring of the state of the repeater , so that when the repeater impaired in the device or on the supply , the clerk did not know in person and just waiting for a report from the repeater keeper at any time at the shelter is not a repeater . There needs to be a device that can monitor the state of the repeater , which if detected interference at the source , supply and radio , PPE JTY officer may direct monitoring , so that it can assist in the handling and analysis of causes of hearing disorders without having to come to the site . GPRS Modem Utilization Intek J65i - X allows retrieval status of the repeater equipment where it can not be done at this time . With facilities tapped digital inputs and digital outputs on the modem , any condition of equipments such as radio signal repeater RX , TX radio signal , battery , charger and 220V supply state of the supply voltage can be detected . From changes in the supply voltage available , can be detected by a GPRS modem Intek J65i - X so that when there is an interruption in the HMI SCADA can termonitoring in real time . With the monitoring and control of a radio repeater communications , personnel no longer need to go to the location (site ) only to find the cause of the disturbance . Interference analysis can also be performed before treatment is held further disruption . Reset control radio can also be done quickly if the radio have to hang in its operation , so that the future will be able to improve the performance of SCADA systems PT PLN ( Persero ) APD Central Java and DI Yogyakarta. Keywords : repeater , modem GPRS Intek J65i - X , auxiliary relays , monitoring and control , HMI SCADA

Development of a Real-Time Model-Prediction-Based Framework for Reset Controller Design

This paper addresses a real-time reset controller design based on the model prediction strategy for process control. Reset control design consists of two main steps: (1) base-system controller design and (2) reset law determination. The base system controller is designed according to the base (no reset) plant dynamics and the reset law is determined by an algebraic condition, which is checked throughout the time for controller state resetting. In this paper, based on the model prediction approach, a linear matrix inequalities (LMI)-based formulation is derived for designing the reset controller. When the reset condition is satisfied, the reset law is computed by solving an LMI optimization problem, and then base-system parameters and current controller states are suddenly changed to new values. This result is used in two examples; numerical simulations verify the efficiency of the proposed approach.

Stability analysis of reset positive systems with discrete-time triggering conditions

This paper discusses the problem of stability analysis of reset positive systems based on discrete-time triggering conditions. A reset control system is positive, if for any nonnegative initial condition and input, its states and outputs are nonnegative whenever the reset actions occur. First, the relationship between reset positive systems (RPSs) with discrete-time triggering conditions and discrete-time switched positive systems (SPSs) is established, by which the stability problem of RPSs is transformed to that of SPSs. Then, some sufficient and necessary conditions of stability and tracking problem for RPSs are given.

An optimal control strategy based on virtual flow measuring for variable flow primary pumping

A virtual flow measuring is integrated with the best efficiency staging and the loop differential pressure (DP) reset method to unleash pump power saving potentials from a variable flow primary pump system. Based on the measured pump head, speed, and power, the virtual measuring determines the pump operation condition in an accurate and fast way. The pump operation parameters are then used to realize the best efficiency staging and the loop DP reset control, which calculate the optimal number of operating pumps and each pump's speed respectively. Simulation shows that this control strategy is most energy efficient, and it saves on pump energy consumption by 74.8% compared with a constant flow pumping system. The experiment from a retrofitted two-pump system also shows that the control strategy provided 64.5% pump energy saving over the original constant flow system. In addition, this control strategy requires a lower initial cost, simplifies the implementation process, makes system operation more reliable and stable, and reduces maintenance demands.

MEASURED ENERGY CONSUMPTION ANALYSIS OF A DISTRICT HEATING SYSTEM UNDER DIFFERENT TEMPERATURE CONTROL STRATEGIES

In this study, the secondary side measured energy consumption of a district heating system (DHS) with different hot water supply temperature control methods was compared. Two control methods were evaluated: an outdoor temperature reset control (OTRC) and an outdoor temperature predictive control (OTPC). While the OTRC strategy has been widely used for energy savings in DHS, the results show that the OTPC strategy resulted in higher energy savings. In general, the OTPC strategy maintained lower supply water temperature, and thereby reduced standby losses and increased overall heat transfer rate to the heated spaces due to higher water mass flow rate to the spaces. During the actual energy consumption monitoring, the OTPC strategy saved about 6.6% more energy compared to that of OTRC strategy. Also, it was found that under partial load conditions, such as during the daytime, the fluctuations in hot water supply temperature with OTRC were more severe than OTPC strategy. Overall, the results showed that the OTPC strategy gave better control and was more stable under full load and partial load conditions.

Network-Based Reset Control Systems With Time-Varying Delays

Reset compensators have shown to have advantages over linear and time-invariant compensators, especially when used in control loops with time delays. In this work, the potentials of reset control in networked control systems are investigated. Specifically, stability conditions are developed for the case in which network-induced delays are time-varying. To this end, it is shown how a network-based reset control system may be represented as a discrete-time reset control system. In addition, both state-dependent and time-dependent discrete-time reset compensators are analyzed. Finally, a case study is developed and simulation results are discussed, showing the superior performance of reset compensation.

A General Form for Reset Control Including Fractional Order Dynamics

Currently, reset control focuses on using structures which allow new resetting rules in order to avoid limit cycle to be caused and improve the performance of the system. This paper investigates the properties of some reset strategies, of integer and fractional order, which reset controller states to fixed or variable non-zero values and are able to eliminate or reduce the overshoot in first and higher order systems, respectively. Based on them, a general reset control strategy with fractional order dynamics is proposed with both fixed and variable resetting to non-zero values. A comparative study is given to show its benefits in terms of prevention of limit cycle and reduction of the overshoot. As a result, some guidelines to be considered for the design of such controllers depending on the application are offered.

Improving ℒ2 Gain Performance of Linear Systems by Reset Control

In this paper, new Lyapunov-based reset rules are constructed to improve ℒ2 gain performance of linear-time-invariant (LTI) systems. By using the hybrid system framework, sufficient conditions for exponential and finite gain ℒ2 stability are presented. It is shown that the ℒ2 gain of the closed loop system with resets can be improved compared with the base system. Numerical example supports our results.

Reset law design based on robust model predictive strategy for uncertain systems

In a continuous time control system, if some of the controller states are reset, certain limitations on the system response can be removed. Moreover, the stability and performance of such a reset control system may be improved. Resetting action has two main characteristics which should be determined: (a) when the controller states are reset and (b) how the after reset values of the controller states are determined. By defining a reset set, when the system states enter this set, the instants for the controller states reset, can be determined. This paper addresses the second question on how to determine the after reset values. In order to design a reset law for real time applications, a model predictive strategy is proposed that specifies the after reset values by minimizing a quadratic performance index. The quadratic minimization problem is converted to a LMI formulation and the reset law is determined by solving this LMI optimization problem at certain reset times. This approach is applied to a typical CSTR system to demonstrate the effectiveness of the proposed method for industrial process control application.

Reset control systems with reset band: Well-posedness, limit cycles and stability analysis

Reset controllers provide a simple way to improve performance when controlling strongly traded-off plants. A reset controller operates most of the time as a linear system, but when some condition holds, it performs a zero resetting action on its state. Recently, some generalizations have been proposed, for example, the anticipation of the reset condition with the so-called reset band. There is a lack of analysis tools for reset systems with reset band. In this paper we address this problem by means of Poincaré maps (PM). It is shown how PM can predict the existence and stability of limit cycles, and give also information on pathologies such as Zenoness, and provide parameter ranges where the system is guarded against those behaviors and thus global asymptotical stability (GAS) is guaranteed.

Bio-inspired coupled oscillatory phase reset control system applied to movement in an underwater vehicle

The present hardware circuit was designed as a fast and energy efficient motor control system based on cerebellar oscillatory neuron activity and network dynamics. Specifically, a hardware model of the olivo-cerebellar dynamics controlling vertebrate motor coordination is used to control movement in an underwater robotic vehicle. Single shot oscillatory phase resetting is used for instantaneous motor plant reorganization based on incoming sensory information. Such a rapid feedback mode, which is rapid enough to prevent animals from falling when they stumble, has been previously described in biological and mathematical papers (Pellionisz and Llinas, 1979, Velarde et al., 2002, 2004). In the present control system, the direction of the vehicle displacement is captured by a camera, and transformed into a phase shift modulation of sets of oscillatory elements that embody internal dynamics. This design provides a novel real time control platform for robotic control in three dimensions.

Overheating in multifamily residential buildings in New York

In this article, we quantify overheating in a sample of hydronically and steam-heated apartment buildings located in New York City, NY. Data have been collected from the archives of companies that provide energy management systems (EMS) to multifamily buildings in the Northeast. Overheating was found in all 18 buildings: the overall average temperature of all buildings was well above 21.1 °C (70 °F) when the EMSs were not in operation, leaving the boilers operate on outdoor reset control, the dominant boiler control type for multifamily buildings. EMS operation is intended to depress overheating. In 15 of the 18 buildings, average temperatures in 100 % of the apartments when EMSs were not in operation were above 21.1 °C (70 °F) [ranging from 21.5 (70.7 °F) to 30.8 °C (87.4 °F)]. In the remaining three buildings, average temperatures in 88 % of apartments were also above 21.1 °C (70 °F) [ranging from 21.5 (70.3 °F) to 29.6 °C (85.2 °F)]. On the other hand, when the EMSs were activated, in seven of 18 buildings, average temperatures in 100 % of the apartments were above 21.1 °C (70 °F) [ranging from 21.5 °C (70.3 °F) to 27.3 °C (81.1 °F)]. In the remaining 11 buildings, average temperatures in 67 % of the apartments were above 21.1 °C (70 °F) [ranging from 21.1 °C (70 °F) to 27.3 °C (81.2 °F)]. Based on this analysis, the estimated average increase in annual space heating energy cost for these buildings due to overheating is approximately 18.6 % when the EMS is off, compared to a baseline average temperature of 21.1 °C (70 °F) all the time. In addition, we employed boiler control systems in three separate hydronically heated buildings that offer aggressive temperature setbacks and one that supplies heat based on apartment temperatures in addition to outdoor temperatures. Results show that after implementing control techniques, heating energy consumption in these three buildings was reduced by 12.7 % to 18.4 % and averaged 16.3 %.

All-Optical Directional Switching in Bistable Semiconductor-Ring Lasers

We investigate the operation of directionally bistable semiconductor-ring lasers as all-optical flip-flops. We demonstrate fast switching between the two lasing directions by injection of optical pulses acting as set and reset control signals with switching times as fast as 20 ps, delay times as short as 60 ps, and switching energy of 150 fJ.

건물 중앙냉방시스템의 에너지절감을 위한 최적운전 방안에 관한 실험적 연구

In this study, optimal operation strategies to save the electric energy and power price in the building central cooling system is researched by experiments. The optimal strategies of demand response control and outdoor temperature reset control algorithms are applied by consideration the electric energy and power price according to the energy consumption characteristics. The suggested optimal control method shows better responses in the power price and energy consumption in comparison with the conventional one and saves energy consumption by 9.5% and electronic price by 15.7%, respectively.

Fractional-order reset control: Application to a servomotor

This paper deals with fractional-order reset control systems and their stability. The possibilities of use of a new fractional-order proportional-Clegg integrator (FPCI) in reset applications are investigated. The key feature of this controller is to tune its order α to achieve an optimized system performance, especially referred to avoid the Zeno solution. The stability of reset control systems is generalized for such fractional-order systems. Fractional- and integer-order reset controllers are designed and compared for the velocity control of a servomotor. Simulated and experimental results are given to show the benefits of using FPCI on the servomotor performance.

Towards [formula omitted]-stability of discrete-time reset control systems via dissipativity theory

This paper proposes conditions on input–output stability of discrete-time reset systems by using some key dissipativity properties. In the continuous-time setting, dissipativity of the base linear system is preserved under reset actions if the storage function is decreasing at reset times. Indeed, when the reset system is a full reset system, the dissipativity of the base linear system ensures the dissipativity of the reset system. However, in the discrete-time setting, this condition on the storage function is not enough to ensure the dissipativity of the base linear system. We define some dissipativity properties of discrete-time reset systems and give an appropriate definition of the reset system in order to preserve the (Q,S,R)−dissipativity of the base linear system under reset actions. As a result, ℓ2-stability of feedback interconnected dissipative control reset systems is obtained.

Frequency domain properties of reset systems with multiple reset anticipations

A reset controller is a controller that operates most of the time as a linear system, except when some condition holds. The typical reset condition is the zero crossing of the tracking error signal, e ( t ) = 0. At this moment, the controller performs a zero resetting action on its state. It has been shown that reset control is able to overcome fundamental linear limitations. This article studies, within a frequency-domain framework, the generalisation of reset control systems based on including some anticipation on the reset condition.This has a favourable phase lead effect. The paper discusses different reset anticipations schemes, including multiple reset actions in the same period, computes Fourier harmonics and describing function of general reset controllers and shows explicitly the overcoming of frequency-domain limitations (Bode's gain-phase relation).

A combined FSP and reset control approach to improve the set-point tracking task of dead-time processes

This paper presents a non-linear control scheme to deal with dead-time processes, specially for systems where fast closed-loop responses are required. The control scheme is based on the combination of two control strategies appeared in the literature to deal with dead-time processes, the Filtered Smith Predictor (FSP), which is a Smith Predictor (SP) including a filter to improve the robustness; and the PI+CI, a PI with a partial reset action on the control signal when the process output reaches the reference input. In the proposed strategy, the reset action allows to achieve very small rise times with small overshoots, improving the results from FSP. On the other hand, the use of the robust predictor allows to deal with the dead-time in a better and systematic way than the existing PI+CI solutions. The improvements of the proposed control scheme are evaluated through simulations and real experiments on an industrial heat exchanger.

A Virtual and Remote Control Laboratory in Moodle: The Ball and Beam System

This paper presents a web-based control laboratory for a ball and beam system that was adapted to be used within an online course of a Learning Management System platform. The experimentation web environment is presented in the context of the UNEDLabs project, a Spanish network of web-based laboratories for science and engineering education. LabView and data acquisition boards are used in the server-side for the remote laboratory application, Easy Java Simulations for the client-side interface of both the virtual and the remote laboratory, and Moodle for the web environment. The integration between the virtual and remote labs and Moodle is achieved thanks to the use of the EJSApp plugins. Recipients of the resulting application are graduate students who can use the advanced control techniques implemented in this web-lab: robust, fuzzy, and reset control.

공동주택 바닥복사 난방시스템의 GRNN 제어 적용에 관한 연구

In this study, the effects of heating control methods on heating control performance and energy consumption in the floor radiant heating control system of residential apartments were research by computer simulation. A general regression neural network(GRNN) control method for reducing indoor temperature overshoot and saving energy in floor radiant heating system is suggested. The GRNN control method shows good responses in comparison with the conventional and outdoor reset control methods for improving indoor thermal environment and reducing energy consumption.