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Based on the sequential batch reactor (SBR) simulation model of the wastewater treatment process for a secondary fiber paper mill that we have developed, two control strategies, a neural network (BP-PID controller) and a fuzzy logic system (Fuzzy-PID controller), were separately combined with PID to control the dissolved oxygen (DO) concentration in the SBR process of paper mill. Two cases, without and with the presence of noise, have been studied and evaluated using the criteria considered in BSM1. For the case without noise, both two-control strategies demonstrated better control indices than that of the traditional PID control; for the case with noise, the Fuzzy-PID controller possessed the good control indices at almost the same expense of aeration energy. The results under two cases showed that the Fuzzy-PID controller demonstrated better performance than that of BP-PID controller, in the DO control of SBR process in the paper mill, Fuzzy-PID controller improved the control performance without increasing the aeration energy consumption.

Total Pressure and Stock Level in the headbox of a paper machine control the quality of paper produced and cross directional flow at the slice. Thus, these are the important parameters to be controlled. With the advancement in artificial intelligence, mathematical approaches that demand high degree of precision has been avoided by using the best estimates in the research work. Soft computing technique i.e. fuzzy logic is used in this paper and the simulation results are compared with classical PID controller.

Paper Machine Dryer sections create challenges in tuning due to gear backlash. The problem is amplified when older Paper Machines are upgraded with newer higher performance drive systems. The newer drive systems can achieve a much higher degree of control that can fatigue the mechanical drive train. Most often, backlash is experienced during the speed regulator tune-up. [1] The speed regulator response is modified in an effort to improve stability while in backlash. However, there are other tune-up considerations that must be taken into account. A Dryer Section can be pulled from downstream sections which can cause the Dryer Section applied torque to be near zero causing speed instability of the Dryer Section. This paper will investigate the cause of this instability and present a novel solution.

Load shedding is critical for facilities that have cogeneration capability to prevent collapse of the cogeneration assets. Fast load shedding requires sub-cycle speed to manage thousands of distributed loads within a facility. This paper describes the experience of applying such a fast load shedding scheme across a wide array of relays provided by various vendors and potentially a large quantity. The system described in this paper utilizes a proven fast load shed system and makes it easy to configure larger and more complex load shed schemes. The paper proposes the architecture of a central fast load shed controller interfaced with local feeder protection relays over IEC 61850 GOOSE and additional fast load shed aggregators if total GOOSE is more than 64. One of the challenges with a large-scale load shed scheme deployment is the configuration of devices, and especially the IEC 61850 GOOSE engineering process which may add further complexity. This paper proposes a simple to configure IEC 61850 GOOSE scheme with high-speed performance requirements. Lessons learned from the fast load shed deployment are also discussed.

The paper mainly introduces the application of closed hood in process of paper produce. This closed hood control system bases on PLC and inverter. In this system, the data collection, calculation, loop control and the communication of PC are completed by PLC. This control system has been applied in medium and small automation transform paper machine. It is practically showed that the output of machine and the stability have been improved by the control system.

Different methods for coordinated motion of the paper or board machine sections were used, mainly depending on the production date. Present solutions are based on individual sectional AC or DC drives as parts of the network control system. The drives are integrated in the control and supervision system with the application of a high performance communication protocol, usually PROFIBUS, Ethernet or DeviceNet. Quality of control system of any paper machine is ensured and the software development procedure is kept straightforward with the use of the universal control block presented in this paper. The generalized structure of the proposed control block is suitable for application on different sections found in paper or board machines, with adequate parametrization. The performance of the block is tested on the dry-end of machine, where the definite amount of sheet tension is required by the technological process. The tension force saliently couples the adjacent drives, which can compromise the performance of the drives, and even lead to unstable operation. The proposed control system structure achieves stable operation of drives coupled through the material, with the possibility to control the sheet tension force.

Actually in paper industry, a single paper machine is required to produce many different grades of paper. These grades are distinguished by various paper indicators. The main indicators are the dry content and water content. In a modern production environment, with paper being tailored to the customer's wishes, the frequency of these grade changes has increased up to the point of multiple changes in a single day. This pushes paper makers to reduce the grade transition time and the waste energy during these transitions. The goal of this research is to study and prototyping techniques able to perform these grade changes. The controller was designed based on Non-Linear Model Predictive Control. The difficulty of the controller design is due to the process to be MIMO with coupled variables and also variable time delay. Moreover the input variables are constrained between upper and lower bounds

Torsional oscillations bound the speed loop bandwidth (BW) of industrial drives and servo systems, deteriorating the transient response to commands and to disturbances. This is especially harmful in multi-drive systems, like paper machines, that need to run synchronized. This paper presents two methods to dynamically compensate the torsional oscillations produced by the compliant components between the motor and the load: either a notch filter or acceleration feedback based on the rigid-body Luenberger observer. The evaluation includes the effect of the reducer backlash, whereby both time and frequency domain responses are used to compare the benefits of each technique in a typical paper machine section. Results show that both methods, if properly tuned, are effective techniques to reduce torsional oscillations, and are robust to parameter variations

A single-inductor multiple positive- and negativeoutput (SIMPNO) converter provides a compact-size and high efficiency solution for electronic paper displays (EPDs) system. With the single inductor multiple output structure, an adaptive current control methodology with the proposed vector current control mode (VCCM) can wisely minimize the current tolerance to be smaller than 10 % between input and all outputs. Additionally, owing to the VCCM technique for adequate inductor current control, the cross regulation is smaller than 0.35 V/A. The test chip was fabricated by 0.25 μm BCD process with a peak value of 90 % at heavy loads.

As to the uncertainty of paper machine in practice, this paper develops multisensor robust H/sub /spl infin// state fusion estimation method to increase the estimation performance of paper basis weight based on LMI theory. The results of experiments show the application of information fusion theory can develops the estimation performance, especially, the performance of state estimation can keep well even when the sensor fails.

This paper studies the capacity, as well as the performance of dirty paper coding (DPC) for a point to point power constrained fading channel given two-sided mixed state information on additive and multiplicative interferences. We show the optimality of DPC when perfect channel state information about fading variable is available to both transmitter and receiver, and provide multiplexing/demultiplexing based strategies to achieve capacity. By employing an adaptation of Heegard's algorithm to this channel model, we also evaluate numerically both the achievable rate of the modified DPC strategy, as well as the actual channel capacity when transmitter has imperfect side information. Numerical results demonstrate significant improvements on channel capacity, as well as increased disparity between the achievable rate using DPC and channel capacity when only one-bit feedback on channel sate information of fading variable is available to encoder. The futility of knowing the additive interference at transmitter, when the multiplicative interference is only available to the receiver, is also shown numerically.

Proper operation of the dry end of a paper machine requires some type of sheet tension control. Present systems use either indirect-speed-control-based schemes, or sensor-based direct tension control utilizing load cells or swing rolls. The indirect schemes are inadequate for most newer machines, and both types of the commonly used sensor-based schemes are invasive, expensive, require either special, or extra rolls, and add complexity to the sheet runs. This paper proposes and evaluates sheet tension estimation using only conventional motor and control signals, present in all newer drive controllers, integrated into a process model observer. This observer-based approach eliminates the need for the invasive tension transducers, and may also be used to replace the inaccurate indirect speed control schemes.

In this paper, a methodology in developing a dynamic model for the pulp preparation in the head-box of paper machine is presented. The set of partial differential equations obtained from the mass balance is solved with respect of the boundary conditions in order to obtain the dynamic version of the model for control in the standard form of the state-space representation. A quantitative discussion on numerical control of multivariable systems with use the reference-model is also presented; it is illustrated how the internal model controller (IMC) can be designed and applied to multivariable systems. The application of the IMC to a head-box in pulp and paper industry is studied, and some simulation test results are presented and discussed in the numerical control manner. >

This paper investigates application of a multivariable control technique to the multi-input multi-output (MIMO) nonlinear model of the paper machine pressurized head box. The proposed controller design is based on a feedback linearization and LQ optimization method. The method can stabilize the system at operating point. In the last, we simulated the performance of pressurized head boxes with the new controller.

This paper considers the design of a controller and a constraint-enforcement scheme for application to dualmode, autonomous and manual steering systems. A tracking controller is designed to track a desired pinion angle during autonomous operation, and to provide assistive torque during manual operation. The tracking controller is designed using H ∞ synthesis with tracking made possible via the solution to a full-information output regulation problem. A reference governor scheme is implemented in order to enforce constraints. Numerical simulations are presented corresponding to an aggressive step-steer maneuver in autonomous mode and show strict constraint enforcement.

A decentralized control scheme is proposed to address a spatially distributed paper machine control problem under industrial investigation. The methodology is based on constrained optimal control and tackles the complexity of the problem by solving local problems of small size, which are coupled through their performance objectives and constraints. Properties of the decentralized scheme are analyzed in detail and compared to the existing centralized receding horizon controller currently used in industry. In terms of the simulated example the decentralized controller can achieve similar performance to the centralized controller but at a fraction of the computational cost.

Feedforward of a new signal based on surface temperature measurements is introduced for the paper machine drying section and its performance is evaluated. Control of the moisture content is conventionally accomplished by adjusting the steam pressure in the cylinders. By adding feedforward to a previously presented mid-ranging control system using two manipulated variables, the disturbance rejection of the moisture control can be significantly improved.

Discrete time orthogonal polynomials such as Gram polynomials have been used In the past to control shape on steel rolling mills. In this paper the authors extend that idea to paper machines and control the parameters of the polynomials, taking into account the maximum bending moment of the slice lip and the relative stiffness of the slice with respect to the actuators. >

This paper presents an improved dynamic matrix control (DMC) algorithm that is suitable for measurement failure and its application for the baseweight control of a paper machine. The main idea of the refined DMC algorithm is to replace the output of a plant with the model output of DMC when measurement failure happens, that is, to control the model by using DMC. To achieve the aim of accurate prediction of the plant output when measurement failure happened, the standard model based prediction in DMC algorithm is improved by replacing the open loop prediction with a close loop prediction. This proposed algorithm has been applied to baseweight control of a paper machine, and the results show that it can process the measurement failure caused by paper breakage in the production process. >

The paper-making process is very complex, there exists long delay time, grievous nonlinearities and time-varying parameters. The paper presents a neuron model-free control method in which the neuron gain is regulated adaptively for the paper-making process. This procedure can control the process with long delay time and great range of open-loop gain variation efficiently. The simulation results for a complex paper machine is satisfying, good performances in robustness and adaptability are obtained.

This paper considers /spl Hscr//sub /spl infin// robustification of an industrial paper machine cross-directional (CD) control system. The existing industrial controller is reinterpreted as a precompensator weight for shaping the open-loop response. The robustification is then achieved by performing a robust stabilization of the nominal plant model and industrial controller combination. The large scale (226 inputs and 226 outputs) /spl Hscr//sub /spl infin//. optimization problem is decoupled into 226 independent SISO systems by an application of recent results for spatially invariant systems. The robustified closed-loop is then implemented by augmenting the industrial controller with a low-order prefilter. It is then demonstrated that the robustness of the closed-loop system has been significantly improved while its performance remains well-preserved.

We propose to use noncausal transfer functions to model the spatial behavior of cross-directional (CD) processes so as to circumvent the high-dimensionality of a causal transfer function. This noncausal representation is shown to have a causal-equivalent form. We prove that the covariance of maximum likelihood estimate of the causal-equivalent model asymptotically converges to that of the noncausal model. This result is then used to design optimal inputs in closed-loop for the original noncausal model of the CD process. An illustrative example is provided to highlight the advantage of using optimally designed excitation signal for CD closed-loop identification over white noise excitation or the current industrial practice of spatial bump excitation.

The online measurement of basis weight in paper production is hampered by excessive noise, and the zig-zagging motion of the scanner transversing the sheet. Decoupling variations in the direction of production form variations across the sheet and visa-versa. An algorithm is presented that attempts to reconstruct this two-dimensional data from the single scanner.

Processing kraft pulp poses a set of difficult control problems, because of varying time delays in the process, an incomplete understanding of the bleaching process and lack of instrumentation. Improved control of the bleaching process increases pulp quality and reduces manufacturing costs. The bleaching process is reviewed, and its problems and existing control solutions are described. Field results from applying a new approach to bleach plant control are presented. The main result is a marked decrease in the standard deviation of pulp brightness, about 40 to 50%. This new approach involves an adaptive controller that models the process as a Laguerre polynomial. >

This article considers wet end modelling of a Fourdrinier table. Cross direction (CD) response to an actuator adjustment is the principal requirement for a good CD basis weight profile control. The physical basis of the model is a surface wave generated by the deflected slice on the surface of the slurry. The wave model combined with the drainage from the wire side establishes the mat formation process. This approach to modelling eliminates the need for estimating a large matrix when a purely time series parametrization of the CD response is considered.

This paper considers suitable disturbance models for use in web forming processes, it suggests a practical disturbance representation and using spectral factorisation presents a multivariable aggregated model. The paper compares Generalised Minimum Variance (GMV) controllers designed using uncorrelated and correlated disturbances. It demonstrates the improvement in performance of a multivariable GMV controller which is designed to accomodate the cross direction correlation in the disturbance, when compared with a scalar GMV controller which cannot take into account the effects of correlated disturbances.

This paper presents an application of a customized linear programming (LP) based model predictive control strategy to the paper machine cross direction (CD) control problem. The objective of CD control is to maintain flat profiles of variables of interest by minimizing worst case deviations from setpoints (defects). These control problems can have as many as 200 actuators (inputs) and 400 sensor measurements (outputs). This large size coupled with the stringent real-time requirement of computing a control move in a few seconds poses a very challenging control problem. Computational results that demonstrate the effectiveness of this strategy are presented. For typical disturbances this algorithm can compute provably optimal control moves for a 400 input/spl times/400 output control problem in approximately 5 seconds versus approximately 90 seconds for a generic LP algorithm on a HP 9000/770 workstation.

Multilevel inverters are highly capable of achieving higher quality output voltage waveforms and higher power ratings with the help of their multilevel structure. They have been of great interest in the field of power industry and are best suited for reactive power compensation. Multilevel voltage source inverters are capable of operating at high voltage with less electromagnetic interference and results in higher efficiency. The harmonic elimination in a multilevel voltage source inverter is of atmost importance and different types of modulation strategies can be applied to the inverters to eliminate these harmonics. Among these modulation techniques, Selective harmonic elimination PWM is a significant switching strategy that can be applied to the output voltage waveform of multilevel inverters for lower order harmonic elimination. This paper gives a review on the various optimization algorithms that is been used for the SHEPWM technique. Performance comparisons of these optimization algorithms in SHEPWM are discussed.

This paper is to design an intelligent traffic light controller using Spartan 3E FPGA (Field Programmable Gate Array) with five-phase traffic control. It adapts to the traffic How for the peak and off-peak traffic time of a day, as well as the traffic patterns during the vacation time.

This paper presents a predictive control system of stepping motor to realize the high speed positioning, and the residual vibration suppression by changing pulse input timing suitably. For the only four pulse input, high speed positioning without residual vibration is strongly required in the high-speed mounting and transferring process of semiconductor tip. In this process, it was made clear from our present experiments that the angular variation response is related to the frictional load between the transferred tape and the guide rail part. The load torque for stepping motor is then added to driving system and the influence of load torqe variation on the angular response variation is studied. Here, we investigate the relationship between angular response characteristics, the load torque and the pulse timing, and propose the predictive control system of stepping motor by feedback of one data in the transient states.

The detection and control of the dry line machine direction position on a fourdrinier paper machine are considered. The dry line position is detected using a digital image processing system consisting of a CCD camera, a frame grabber and a standard PC. The system was installed on a kraft liner machine and both open loop and closed loop experiments were performed with encouraging results. The introduction of automatic control of the dry line position reduces the time for grade changes and it also reduces the machine operators work load. The reduced time leads to smaller production losses and hence to economical benefits. Godkänd; 1998; 20061029 (ysko)

Since the minimum variance controller (MVC) provides the smallest achievable output variance, performance indices based on minimum variance benchmarking have been applied extensively to both univariate and multivariate systems. This paper extends the idea of minimum variance benchmarking to the performance monitoring of cross-directional (CD) processes in paper machines. A performance index is proposed based on the spatial and temporal minimum variance benchmark for the CD process. Computational complexity of the high dimensional time series estimation is reduced by taking advantage of the special structure in the coefficient matrices. Illustrative examples from a paper machine simulator and industrial data sets are provided to show the effectiveness of the techniques as well as the insensitivity of the performance index to high frequency spatial disturbances.

This paper presents the application of two GPC strategies, multiple model GPC and adaptive GPC, to the SIMULINK model of a paper machine. The plant features a rather large dead-time and severe filler retention variations at the wire section. In multiple model GPC an extra sensor measuring the retention level is used to select between a set of linear models identified at various fixed retention levels. At each sampling instant the selected model is employed in a normal GPC scheme. Simulation results show that the performance is much improved when compared to the fixed GPC case. The adaptive GPC method considered in this paper updates the gains of the plant transfer matrix using two 2-input-1-output least-squares estimators. Results indicate that the control is noticeably tighter than the fixed GPC case, at a price of more oscillatory responses. >

The paper machine cross-directional (CD) process is an industrial spatially distributed system. Paper properties are controlled by a set of different actuator arrays acting in the cross direction (CD) as the paper sheet moves along the machine direction (MD). The industrial custom is to identify CD models from bump tests that are run in open-loop. This article presents a technique for CD response shape, alignment and dynamics model identification. The spatial response is identified by a no causal spatial FIR model that accounts for the actuator response in the cross-direction (CD). A novel technique for CD alignment detection is presented through disconsolation of the measurement profile. The spatial model identification is followed by estimating the CD process dynamics. The CD model identification technique is extended to feedback loops running under model predictive control (MPC). CD process models are identified in closed-loop from short identification experiments in a low signal-to-noise ratio (SNR). The proposed technique is validated by conducting identification experiments on an industrial paper machine model running under MPC.

Rotary press tension control works as a key control section in affecting the quality of printing products. Particularly, it plays a major role to overprint precision. This paper analysed several factors affecting rotary press tension control and difficult problems regarding setting parameters of conventional PID control in tension control. On the basis of fuzzy self-adaptive PID tension control device, the paper attempted to adjust real-time parameters Kp, Ki, and Kd according to deviation and deviation rate. The paper further analysed principles of fuzzy self-adaptive PID control and sectional functions. Then the paper designed a solution to tension control applying fuzzy self-adaptive PID. Practice indicated that fuzzy self-adaptive PID has better control characteristics than conventional PID controller in tension control. Exogenous interference has no effect on the basic tension control way, making paper tension control performance to be fast, accurate and stable.

The performance of a model-based controller depends inextricably on the quality of the corresponding model. The performance of such a controller is optimal with respect to the model. Therefore any model-plant mismatch can be expected to result in poor performance. The objective of this work is to study the sensitivity of commonly used performance indices to model-plant mismatch. A sensitivity measure is defined and a frequency domain expression for quantifying the sensitivity is derived. It is shown that the sensitivity of the performance indices varies for different types of model mismatch, e.g., gain mismatch, etc. Furthermore, model mismatch has different effects on the performance of the system when it is operating in steady state or in a transitional mode. These differences can reveal the type of plant-model mismatch. The results are illustrated on industrial paper machine data.

In order to find an effective control measure for paper cutting machine of papermaking plant, a novel motor feedforward and fuzzy PID control strategy was proposed in is paper. Feedforward controller transfer function was obtained according to the dynamic mathematical model of DC motor. The speed closed-loop control was realized based on fuzzy control algorithm. According to comparison of industrial application results, the control strategy can accurately restrain the load disturbance and improve the control effect of synchronization for the cutter speed.

Paper tension is the most important control parameter in roll material production that directly impacts the printing quality of the web offset. Based on the closed-loop paper tension control theory, by conducting a research into the simulation of paper tension control system with MATLAB/SIMULINK, presented the closed-loop control diagram about the paper tension control system. Under different control parameter, the value of the overshoot, respond speed and residual of the system varies. As a result, the quantitative research on the simulation of the system offers a valid means in improving the control accuracy.

It is very difficult to accurately control the speed of paper roller and sword roller of the paper cutting machine, and the proportions of two paces control have greater randomness. Alterable fuzzy-PI control arithmetic is put forward based on PLC. The alterable fuzzy controller and the PI adjustor are realized by PLC. This system has solved the problem that grain flow equilibrium, not stably does not kind. The practical results show that this system can restrain the effect of time relaying effectively and good stability and strong robustness.

This paper describes plain paper copier (PPC) paper manipulation using electrostatic induction. The principle of electrostatic induction has been known for many years, but it has not been extensively studied due to its low output performance. In this study, the principle is applied to paper sheet manipulation that does not require high output. A possible application of the paper sheet manipulation is, for example, tangible desktop interfaces. In our previous work, a tangible desktop interface using electrostatic actuator was proposed, which utilized surface actuator called Image Charge Stepping Actuator. The actuator can directly handle sheet materials on it. However, it has a limitation that the actuated sheet needs to have surface resistance of around 1013Ω. Typical PPC paper has smaller surface resistance and thus an alternative actuation technology is required. In this paper, electrostatic induction was utilized as an alternative to handle PPC paper. The paper investigates the basic performance of induction actuator in terms of PPC paper handling. The frequency response is characterized using a 1-DOF prototype which found the optimum driving frequency of around 1 kHz. Then, a planar 3-DOF manipulation system is prototyped using four 1-DOF electrode panels. The system demonstrated planar 3-DOF motions, which are X translation, Y translation, and rotation around the center. Although the motion stroke is limited, the motion speed reached 150 mm/s for translational motion and 15 rad/s for rotational motion.

Non-fragile robust control problem of a paper basis weight is studied. It is pointed out that this problem is really a non-fragile robust performance problem, the problem with both non-fragile robust stability and performance requirements(bandwidth and disturbance attenuation). It is also suggested that the design of the non-fragile robust performance can be formulated as a μ-synthesis problem, if the uncertainty weighting function and the performance weighting function to system bandwidth and disturbance attenuation are revised appropriately. The μ-synthesis non-fragile robust PI controllers of the paper basis weight control system are solved. The results show that the proposed method is efficient and feasible.

The purpose of this paper is to present a state variable model for the drying section of a paper-making machine. This model is based on the mass and energy balance relationships written for steam, paper, cylindrical heater wall, and moisture. These relationships give a set of six nonlinear partial derivative equations. The form of these equations changes somewhat from one cylindrical heater to another. The solution for this model yields the operating parameters needed to achieve the desired steam temperature while obtaining good paper drying. Boundary conditions are specified by a stochastic generator, and initial conditions are obtained by solving the static model. In this paper, the authors present only the state variable model for the paper drying, as well as comparing the obtained results with dynamic model results. Solving the set of differential equations with respect to the boundary conditions, they obtain the standard form of the state representation, which represents the dynamic version of the model used for process control. In conclusion, it can be said that the consistency of the model with experimental results seems to be reasonably good and can be used for process control.

The problem that paper breaking can be caused by many factors in papermaking process, the dynamic transition of paper breaking must be reflected to the change of some random variables including speed of paper machines, consistency of pulp, quantitative and moisture of paper, which is called paper breaking parameters, by way of non-stationary random signals. The non-stationarity of these random signals will boost up rapidly with paper breaking process. According to the phenomenon a new method predicting paper breaking based on analyzing con-stationary property of random signals of paper breaking parameters is presented here. During the prediction process, the non-stationarizing amplitude of these random signals are estimated by the distance of 1.5 dimension cepstrum, and a paper breaking predictor is formed by proportional-integral-derivative algorithm of 1.5 dimension cepstrum of paper breaking random signals on line so that paper breaking can be judged in time from variation of 1.5 dimension cepstrum. The correctness and the practicality of this method are shown by application results.

Torsional oscillations greatly affect performance and determine the bandwidth (BW) and damping of speed loops. Backlash due to gear reducers can also contribute to the triggering of oscillations, especially when the drive runs at very low load torque. This paper presents a detailed evaluation of these effects in typical electro-mechanical drive trains applied to paper machine sections. The cases evaluated consider torsional oscillations in two-mass and three-mass systems, and the effect of shaft diameter and length on the resonance frequencies of three typical paper machine sections. Time domain response plots are evaluated to show the effect of speed response overshoot, reducer backlash, and step or ramp speed commands. Based on these results, mechanical design guidelines are given for the most significant drive train components in order to minimize torsional oscillations of the speed controlled drive system.

The presence of condensate inside the dryer cylinders of paper machines produces an important increase of the required torque and power during the startup. A condensate load over 1% accumulated can produce a drive overload and eventually an overload trip.

Large penetration of photovoltaic systems at the distribution network level can be one of the causes of high fluctuating voltage. In this study the authors present a voltage control method based on the modulation of the reactive power production of the power conditioning system (PCS) of the PV. The study evaluate the efficiency of constant voltage control, proportional voltage control and constant power factor control in a test facility with a single PCS and 4 PCS connected in parallel. The test results confirm that the constant and proportional voltage control methods are the most effective solution to control the voltage in the distribution network.

Aimed at the strong coupling between basis weight and moisture content in papermaking, this paper put forward a decoupling method based on neural network, which is realized by designing a computing network to offset coupling in the process, and makes generalized object's transfer function matrix become diagonal. By decoupling control, we used slurry flow to control basis weight and steam flow to control moisture content successfully, and achieved good control effect. The actual operating results showed that this control algorithm can improve the profits of enterprises greatly and has some practical value.

Paper making and processing applications require several drives that need to deliver high performance, in particular considering the high speed operation of the newer machines. Electronic synchronization is now used instead of mechanical transmissions to assure the quality of the produced paper rolls. The resulting increased complexity of the controls is offset by the simplification of the mechanics. A five-drive paper system is studied using Energetic Macroscopic Representation. A control scheme is deduced from this graphical model. The modeling and control development methods lead to a structured control scheme composed of many simple and easily tuned controllers, which ensure a natural decoupling of each drive despite their non-linear coupling induced by the elastic band sections.