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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.

When an X-ray photon which is generated by the sample enters into the detector, pulses can be produced and recorded. The detector is unable to respond to another photon that enters at the same time when a photon is being detected. The time that the detector takes to respond to a photon is regarded as dead time. For the x-ray fluorescence detector, the recorded count is less than the real count impulse due to dead time. Hence, to correct x-ray intensity of samples whose element content is vastly different, determination of dead time is necessary. In this paper, a new and complete way to determine dead time is proposed, which can be summarized as “intensity pair method”. Three “intensity pairs” were used for determining dead time, which were “intensity pair” of collimators (S2 and S4), “intensity pair” of spectral lines (Kα and Kβ) and “intensity pair” of beads with different flux-sample ratio (higher SH and lower SL analyte content in the beads). It comes to a conclusion that dead time obtained from “intensity pair” of beads is the most practical method for correcting X-ray fluorescence intensity. As for routine analysis, the dead time of proportional counter can be accurate to 1×10-9s, which can make intensity correction error less than 0.1%.

This paper proposes a new dead time compensation method of independent six-phase permanent magnet synchronous motors (IS-PMSM). The current of the independent phase machines contains odd-numbered harmonics because of the dead time and the nonlinear characteristics of the switching devices. By using the d-q-n three-dimensional vector analysis, these harmonics can be extracted at the n-axis current. Thus, the current distortion can be compensated by controlling the n-axis current of the IS-PMSM to zero. The proposed method is simple and can be easily implemented without additional hardware setup. The validity of the proposed compensation method is verified with simulations and several experiments.

This paper presents a new dead-time compensator for stable and integrating processes when a reduced model of the process is considered. The output is estimated from a discrete time representation of the continuous time model and the tuning of the controllers can be made by any classical control design approach for systems without delay. The internal stability and the robust stability of the proposed scheme is proved and a deep analysis of the disturbance rejection performance is included. As a result, a tuning procedure is derived. An illustrative example shows that the robustness and performance of the proposed scheme are similar or better to those of the more recently proposed dead-time compensators for stable and integrating processes, its capability to reject ramp disturbances being also addressed. The proposed scheme has been tested in a real-time application to control the roll angle in a laboratory prototype of a quad-rotor helicopter.

Single-photon sensor technology is rapidly emerging as the optical sensor technology of choice in specialized low flux imaging applications such as long-range LiDAR, fluorescence microscopy and non-line-of-sight imaging. We ask the question: Can single-photon sensors be used more broadly as general-purpose image sensors for passive 2D intensity imaging? We derive a photon flux estimator using the number of photons detected in a fixed exposure time by a dead-time-limited single-photon avalanche diode (SPAD) sensor. Unlike a conventional image sensor pixel that has a hard saturation limit due to its full well capacity, our SPAD-based passive imaging method has a non-linear response that never saturates. This enables SPADs to operate not only at extremely low photon flux levels but also at extremely high flux levels, several orders of magnitude higher than the saturation limit of conventional image sensors. We present a comprehensive theoretical analysis of the effect of various design parameters on the signal-to-noise-ratio and dynamic range of a passively operated SPAD pixel, and also demonstrate the dynamic range improvement experimentally.

We propose a simple design method of filtered Smith predictor that belongs to a class of dead-time compensators. Simulation results show that disturbance rejection performs well for unstable and integrative plants with dead-time.

Dead-time is added into traditional pulse width modulation (PWM) control to avoid short circuit of DC link of inverters. The dead-time can cause problems such as voltage loss, increasing the value of total harmonic distortion of the current waveform (THDI) as well as output current distortion at the zero-crossing. To solve these problems, many studies have been made to deal with the dead-time issues. This paper presents a novel dead-time effect elimination method for H-bridge inverters based on three-level PWM strategy. In this paper, a new current polarity detection circuit has been used to remove dead-time between signals. This detection circuit is based on the conduction states of two low antiparallel diodes in IGBT modules. Here, only one power supply is needed for the diode states conduction detection. In this paper, the principle of the proposed method is detailed. Moreover, simulation and experimental results are presented to demonstrate the validity of the proposed method.

The Conventional Sliding Mode Observer (SMO) collects the rotor position angle information by identifying rotor position angle and needs to introduce phase-locked loop (PLL) to realize the reverse control. It has certain limitations including massive calculation, slow dynamic response and complex methods and not taking the effect from the inverter dead-time on the estimation model into consideration during the identifying process. To solve the problems, a new sensorless control method for the adaptive SMO based on rotating coordinate system considering dead-time is proposed. In this method response speed is improved by adopting rotating speed as control variable and phase error between actual motor and model motor is removed by introducing dead-time compensation in model motor. Then adaptive law of the estimated rotation speed is acquired through the Lyapunov non-liner design. It significantly simplifies the algorithm and can achieve reverse control at the same time. The effectiveness and feasibility have been proved by the results of the simulation and experiment.

The input to the sugar factory is the sugarcane billets and the output is the crystal sugar. There are many subprocesses with significant multivariable interaction involved within this process which is cane preparation, juice extraction by crushing mill, heating, clarification and filtration, evaporation, and crystallization. In the present paper, the Smith predictor is designed using MATLAB in order to compensate the dead time present in heat exchanger system of the crystallization process and its performance is compared to that of a conventional PI controller with no dead time compensation.

An improved commutation technique for the ac-ac output converter circuit of a pulse width modulated high frequency link (HF-link) inverter is proposed in this paper. The high frequency link inverter converts a DC input voltage into line frequency AC output voltage using a high-frequency transformer for voltage step-up and galvanic isolation, without an intermediate rectification and dc bus. In this topology, there is a direct ac-ac converter which processes the HF-link square-wave voltage into the desired sinusoidal ac output voltage. To do this requires a commutation method to prevent shoot-through when output current changes direction or commutâtes from one switch to the next. Conventionally, dead time is used but this adds distortion to the output waveform. Previously a commutation technique without dead time was introduced but it required a number of assumptions on the inverter load impedance and link voltage characteristics that made it useful for a stand-alone R-L load but not practical for grid connection. The commutation method in this paper does not require dead time and does not impose any limitation on the output inductance and link voltage magnitude and frequency. Simulations were performed using MATLAB and Plexim, experimental verification used the dSpace 1007 HIL platform.

This work proposes an anti-windup dead-time compensator (DTC) based on a generalized predictive controller (GPC). At first, it is analysed the dead-time compensation properties of the GPC by its formulation in a DTC structure. Secondly, a saturation model is added in order to overcome windup problems. The proposed control structure does not use any extra tuning parameter due to the anti-windup characteristic. Simulation results are used to compare the proposed controller with others anti-windup DTCs proposed in literature.

This paper proposed a compensation method for reducing sampling delay through ADC(Analog-to-Digital Converter) module of MCU(Micro Controller Unit) using ZDPWM method. In case of conventional PWM method of 3-level NPC inverter, the switching devices which is composed of silicon compounds are conducted complementary operation by both reference and carrier waveform. And this operating method needs to contain dead time state to prevent short-circuit fault. However, the phase voltage distortion is caused by the dead time state in conventional method. As a results, THD of phase current is increased when inverter system is operating. ZDPWM method which is non-complementary operation is suggested to compensate the distortion through dead time in 3-level NPC inverter. The ZDPWM method has some advantages such as simple operation through carrier waveform as same as conventional method and low harmonic factor at phase current based on non-complementary operation. However, the unexpected distortion of phase current can occur by phase angle delay through sampling of ADC module when the ZDPWM is used in experiment by MCU. Therefore, this paper proposed simple method to compensate sampling delay based on the modeling of delayed phase angle. The proposed method is demonstrated by experiment, and the method compares with same conditions as both conventional PWM method and the ZDPWM due to uncompensated sampling delay.

In this paper control of multi-phase induction drives is discussed. Structure of six-phase frequency inverter is examined. The article deals with dead-time generation circuits in six-phase frequency inverter for transistor control signals. Computer models of dead-time circuits is created using LTspice software package. Simulation results are compared with experimental results of the tested dead-time circuits. Parameters obtained in simulation results are close to the parameters obtained in experimental results. Santrauka Šiame straipsnyje atskleistas daugiafazių asinchroninių pavarų valdymas, išnagrinėta šešiafazio dažnio keitiklio sandara. Straipsnyje nagrinėjama šešiafazio dažnio keitiklio inverterio tranzistorių valdymo signalų vėlinimo grandinės. Sudaryti jų kompiuteriniai modeliai, naudojant LTspice programinį paketą gauti grandinių imitaciniai rezultatai, kurie palyginti su eksperimentiniais šių grandinių tyrimo rezultatais. Gaunamos imitacinių rezultatų parametrų vertės yra artimos eksperimentinių tyrimų rezultatams. Reikšminiai žodžiai:daugiafazės pavaros, dažnio keitiklis, skaliarinis valdymas, šešiafazis asinchroninis varikli.

In recent years, the three-phase pulse width modulation controlled voltage source converter (PWM-VSC) has found its way to wide range of applications, among which renewable energy sources and adjustable speed drives are the most common. In order to achieve low harmonic distortion of current at the point of common coupling (PCC), LCL filters are used for grid connection since they ensure higher damping of current harmonics than L-filters for the same volume. There are many different LCL filter design and optimization methods that are based on the assumption of an ideal converter. Since actual PWM-VSC includes many different sources of nonlinearities, their neglection can potentially lead to selection of inadequate LCL filter in terms of increased grid current harmonic distortion and decreased overall system performance. Research presented in this paper is part of ongoing effort to increase efficiency of adjustable speed drive for crane systems of which the PWM-VSC with LCL filter is a part. This paper focuses on influence of nonlinearities on voltage harmonic spectrum of PWM-VSC. Analysis is carried out by means of nonlinear models and it indicates that the dead time delay has the greatest impact on the system. Validation of simulation results by measurements suggest additional effects should be incorporated into the model. Such a model can then be used for development of more accurate non-iterative LCL filter design and optimization procedures as well as development of operating point optimization algorithms.

Thearticle presents Finite Control Set Model Predictive Control for an AC/DC converter with a LCL filter. The extended cost function J is responsible for the adjustment of controlled values. An important issue raised in the article is the impact of dead time on the prediction of controlled values. The negative impact of dead time results in an increased THD of the grid current. The article proposes an algorithm correcting the impact of dead time which was confirmed by the results of Matlab-Simulink simulations and laboratory tests.

An integrated synchronous buck converter with a high resolution dead time control for input voltages up to 48V and 10MHz switching frequency is presented. The benefit of an enhanced dead time control at light loads to enable zero voltage switching at both the high-side and low-side switch at low output load is studied. This way, compact multi-MHz DCDC converters can be implemented at high efficiency over a wide load current range. The concept also eliminates body diode forward conduction losses and minimizes reverse recovery losses. A dead time resolution of 125 ps is realized by an 8-bit differential delay chain. A further efficiency enhancement by soft switching at the high-side switch at light load is achieved with a voltage boost of the switching node by dead time control in forced continuous conduction mode. The monolithic converter is implemented in an 180nm high-voltage BiCMOS technology. At VIN = 48V, VOUT = 5V, 50mA load, 10MHz switching frequency and 500 nH output inductance, the efficiency is measured to be increased by 14.4% compared to a conventional predictive dead time control. A peak efficiency of 80.9% is achieved at 12V input.

This paper presents a novel approach to compensate the voltage error due to switching dead times in voltage-fed inverters using a field-programmable gate array (FPGA) and current oversampling. The FPGA controls an analog-to-digital (AD) converter which operates at a high conversion rate and processes numerous current samples taken at equidistant time steps within each pulse width modulation (PWM) period. The FPGA also generates the inverter's PWM modulation. As phase currents at an inductive load can be approximated by piecewise linear time functions during each switching state of the inverter, the FPGA interpolates the current slopes using a linear least mean squares regression. Based on this regression, a predictor structure in the FPGA predicts the phase current right at the beginning of the switching dead time. The predictor structure can be computed almost instantaneously due to parallel data processing. Based on the estimated phase current, the FPGA uses a lookup table, depending on current and DC link voltage, to correct an upcoming switching instant in order to compensate for the dead-time effect. Depending on current polarity and magnitude, the lookup table stores the respective compensation times for the upcoming switching instants. The lookup table is the result of an offline commissioning process.

Inverter dead-time, which is meant for safe commutation of devices is known to induce sub-harmonic oscillations in lightly-loaded induction motor drives operating in open-loop. This paper presents an experimental procedure to determine whether a given motor drive would exhibit such oscillations, and if yes, the region of such oscillatory behaviour. In particular, this paper presents case studies on oscillations on account of dead-time in inverter-fed 5-HP and 10-HP induction motor drives. Experimental measurements are made at different fundamental frequencies and different flux levels (or V/f ratios) to identify if the motor drive exhibits oscillatory behaviour at these various operating points. The regions of oscillatory behaviour of the two motors under no-load are identified experimentally in terms of applied voltage and modulating frequency. A simple dead-time compensation scheme is employed to mitigate these low-frequency oscillations. The experimental waveforms and corresponding Fast Fourier Transform (FFT) analysis of the motor currents demonstrate the sub-harmonic oscillations and their mitigation.

This paper describes the performance of PID controllers based on internal model control (IMC) technique for two input and two output (TITO) process with dead time. Centralized inverted decouplers are intended to minimize the interactions between the loops. With appropriate choice of decoupler each decoupled subsystem seems to be first order plus dead time (FOPDT) process in nature. Two separate IMC-PID controllers are designed for each decoupled subsystem. An overall improved response is found from both the loops by using first order filter and suitable choice of close-loop time constant. Performance based comparison with other IMC technique substantiates the competence of the proposed method.

The objective of this paper is to study the influence of inverter dead-time on steady as well as dynamic operation of an open-loop induction motor drive fed from a voltage source inverter (VSI). Towards this goal, this paper presents a systematic derivation of a dynamic model for an inverter-fed induction motor, incorporating the effect of inverter dead-time, in the synchronously revolving dq reference frame. Simulation results based on this dynamic model bring out the impact of inverter dead-time on both the transient response and steady-state operation of the motor drive. For the purpose of steady-state analysis, the dynamic model of the motor drive is used to derive a steady-state model, which is found to be non-linear. The steady-state model shows that the impact of dead-time can be seen as an additional resistance in the stator circuit, whose value depends on the stator current. Towards precise evaluation of this dead-time equivalent resistance, an analytical expression is proposed for the same in terms of inverter dead-time, switching frequency, modulation index and load impedance. The notion of dead-time equivalent resistance is shown to simplify the solution of the non-linear steady-state model. The analytically evaluated steady-state solutions are validated through numerical simulations and experiments.

This paper presents a new software-based on-line dead-time compensation technique for single-phase grid-connected photovoltaic (PV) inverter system. To improve the mitigation of dead-time effect around the zero-crossing point of phase current, a selective harmonic elimination of instantaneous feedback current is used as an additional part of conventional current control scheme. Simulation and experimental results are shown to verify the effectiveness of proposed compensation method in the gridconnected power distributed generation systems.

A simple on-line elimination strategy of the dead time and inverter nonlinearity using the current slope information is presented for a PWM inverter-fed IPMSM (Interior Permanent Magnet Synchronous Motor) drive. In a PWM inverter-fed IPMSM drive, a dead time is inserted to prevent a breakdown of switching device. This distorts the inverter output voltage, resulting in a current distortion and torque ripple. In addition to the dead time, inverter nonlinearity exists in switching devices of the PWM inverter, which is generally dependent on operating conditions such as the temperature, DC link voltage, and current. The proposed scheme is based on the fact that the d-axis current ripple is mainly caused by the dead time and inverter nonlinearity. To eliminate such an influence, the current slope information is determined. The obtained current slope information is processed by the PI controller to estimate the disturbance caused by the dead time and inverter nonlinearity. The overall system is implemented using DSP TMS320F28335 and the validity of the proposed algorithm is verified through the simulation and experiments. Without requiring any additional hardware, the proposed scheme can effectively eliminate the dead time and inverter nonlinearity even in the presence of the parameter uncertainty.

To deal with the problem that dead time is indispensable and that its compensation is difficult to implement especially when taking Space Vector Modulation method to modulate the inverter stage of Two-Stage Matrix Converter (TSMC), this paper presents a Carrier-based Modulation (CBM) strategy suitable for the TSMC and amplifies concerned the uniqueness of the proposed CBM. Based on this, the dead-time effect to TSMC is analyzed, formula for describing dead-time effect is induced, and two compensation methods are given, namely modulation voltage modification method and time compensation method. At last, the uncompensated and compensated experiments are carried out on the prototype, and the results prove that this strategy meets the satisfaction.

This short communication analyzes the results recently presented in the paper “On a novel dead time compensator for stable processes with long dead times” published in the Journal of Process Control . In the mentioned paper it is argued that the proposed strategy, called modified Smith predictor (MSP), gives better performance than the filtered Smith predictor (FSP) dead-time compensator for stable processes with dead time. In fact MSP has the same structure as FSP and only some specific tuning rules of the filters are proposed. Therefore, in this work some aspects of the comparative analysis and tuning rules presented in the referred paper are discussed to show that MSP is a particular case of FSP and that for some particular cases its tuning rule does not allow for a good closed-loop response. Some simulation case studies are used to illustrate these aspects.

In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control strategy can eliminate the problems of the dead time effects. But the traditional non-dead-time control strategy heavily depends on the current zero-crossing detection, which may cause the output voltage distortion or even a short circuit. Based on the analysis of the reason for the distortion, a new optimized non-dead-time control method is proposed. Two methods for the detection of the overlapping area are enumerated. The conclusions are confirmed by the simulation results with MATLAB/ SIMULINK.

Dead-time effects result in a non-linear detector response in the common time-of-flight secondary-ion mass spectrometry instruments. This can result in image artifacts that can often be misinterpreted. Although the Poisson correction procedure has been shown to effectively eliminate this non-linearity in spectra, applying the correction to images presents difficulties because the low number of counts per pixel can create large statistical errors. The efficacy of three approaches to dead-time correction in images has been explored. These approaches include: pixel binning, image segmentation and a binomial statistical correction. When few pixels are fully saturated, all three approaches work satisfactorily. When a large number of pixels are fully saturated, the statistical approach fails to remove the dead-time artifacts revealed by multivariate analysis. Pixel binning is accurate at higher levels of saturation so long as the bin size is much smaller than the feature size. The segmentation approach works well independent of feature size or the number of fully saturated pixels but requires an accurate segmentation algorithm. It is recommended that images be collected under conditions that minimize the number of fully saturated pixels. When this is impractical and small features are present in the image, segmentation can provide an accurate way to correct for the detector saturation effect.

In a PWM inverter-fed IPMSM (Interior Permanent Magnet Synchronous Motor) drive, a dead time is inserted to prevent a breakdown of switching device caused by the short-circuit of DC link. This distorts the inverter output voltage resulting in a current distortion and torque ripple. In addition to the dead time, nonlinearity exists in switching devices of the PWM inverter, which is generally dependent on operating conditions such as the temperature, DC link voltage, and current. The voltage disturbance caused by the dead time and inverter nonlinearity directly influences on the inverter output performance, and it is known to be more severe at low speed. In this paper, a new compensation scheme for the dead time and inverter nonlinearity under the parameter variation is proposed for a PWM inverter-fed IPMSM drive. The overall system is implemented using DSP TMS320F28335 and the validity of the proposed algorithm is verified through the simulation and experiments.

The usability of current active personal dosemeters is compromised in pulsed radiation fields due to dead-time effects. This paper presents methods to quantitatively predict dead-time behaviour for a given dosemeter in arbitrary radiation fields, which are derived from simple theoretical models. For several pulse shapes, simple numerical parameterisations based on Monte Carlo simulations are given. The case of multichannel dose measurement is discussed separately. It is shown that the use of several independent detectors can significantly improve the dosemeter performance.

This paper presents a unified approach for tuning PID controllers for stable, integrative and unstable dead-time processes. The approach is based on a PID approximation of the Filtered Smith Predictor that allows to control this kind of processes looking for a trade-off between performance and robustness. The proposed control tuning method is simple to analyze and use. Cases studies are included to illustrate the advantages of the proposed tuning rules. Furthermore, comparisons with other existing methods are presented to show that the proposed unified method provides promising results.

This paper discusses the voltage error caused by the dead time in voltage-source PWM converters. The theoretical analysis in this paper derives the nonlinear voltage error paying attention to the parasitic output capacitance in each switching device. The analytical result reveals that the turn-off current or the switching current ripple strongly affects the voltage error. In addition, it is clarified that the conventional compensation methods based on linear and three-level approximation are suitable under small and large current ripple conditions, respectively. A simple calculation method of current ripples in three-phase PWM converters are also developed to estimate the turn-off currents. A new compensation method based on the analysis is developed and compared with three different conventional methods in experiments using a 200-V, 5-kW three-phase grid-connection converter. The analysis-based method exhibits a good compensation performance having a lower current THD than the conventional methods in allover the operating range.

Model predictive control (MPC) is an effective control strategy in the presence of system constraints. The successful implementation of MPC in practical applications requires appropriate tuning of the controller parameters. An analytical tuning strategy for MPC of first-order plus dead time (FOPDT) systems is presented when the constraints are inactive. The available tuning methods are generally based on the user's experience and experimental results. Some tuning methods lead to a complex optimisation problem that provides numerical results for the controller parameters. On the other hand, many industrial plants can be effectively described by FOPDT models, and this model is therefore used to derive analytical results for the MPC tuning in a pole placement framework. Then, the issues of closed-loop stability and possible achievable performance are addressed. In the case of no active constraints, it is shown that for the FOPDT models, control horizons subsequent to two do not improve the achievable performance and control horizon of two provides the maximum achievable performance. Then, MPC tuning for higher order plants approximated by FOPDT models is considered. Finally, simulation results are employed to show the effectiveness of the proposed tuning formulas.

This paper introduces a method for dead time optimization in variable speed motor drive systems. The aim of this method is to reduce the conduction time of the freewheeling diode to a minimum without generation of cross conduction. This results in lower losses, improved EMC, and less overshooting of the phase voltage. The principle of the method is to detect beginning cross currents without adding additional components in the half bridge like resistors or inductances. Only the wave shape of the phase voltage needs to be monitored during switching. This is illustrated by an application of the method to a real power converter.

The most common technique used in pulse electron paramagnetic resonance spectroscopy to determine interspin distances in the nanometer range is pulse electron double resonance, while relaxation-induced dipolar modulation enhancement (RIDME) is a promising alternative to this method. In this article we introduced a selective hole-burning technique for RIDME experiment, which allows dead-time free measurement of dipolar modulation without the use of the second microwave frequency or a magnetic field jump. This technique was tested on a short, stable biradical in a frozen solution, and the optimal experimental conditions for the measurement of dipolar modulation were found. Interspin distances in the range of 13 A ≤ r ≤ 25 A can be measured by the proposed method.

Recent developments in the field of fluorescence lifetime imaging microscopy (FLIM) techniques allow the use of high repetition rate light sources in live cell experiments. For light sources with a repetition rate of 20-100 MHz, the time-correlated single photon counting (TCSPC) FLIM systems suffer serious dead time related distortions, known as "inter-pulse pile-up". The objective of this paper is to present a new method to quantify the level of signal distortion in TCSPC FLIM experiments, in order to determine the most efficient laser repetition rate for different FLT ranges. Optimization of the F -value, which is the relation between the relative standard deviation (RSD) in the measured FLT to the RSD in the measured fluorescence intensity (FI), allows quantification of the level of FI signal distortion, as well as determination of the correct FLT of the measurement. It is shown that by using a very high repetition rate (80 MHz) for samples characterized by high real FLT's (4-5 ns), virtual short FLT components are added to the FLT histogram while a F -value that is higher than 1 is obtained. For samples characterized with short real FLT's, virtual long FLT components are added to the FLT histogram with the lower repetition rate (20-50 MHz), while by using a higher repetition rate (80 MHz) the "inter-pulse pile-up" is eliminated as the F -value is close to 1.

This article presents a method to control and stabilise systems with pure input lag. The approach is based on a new state predictor which estimates the future of states and guarantees that the prediction error converges asymptotically to zero. The state feedback controller is then designed based on this predictor. Furthermore, a sequential structure of sub-predictors is presented for unstable systems with a long time-delay and accordingly the controller is designed for asymptotic stability. The core idea is to design a series of coupled predictors, each of which is responsible for the prediction of one small portion of the delay, such that the predictors collectively predict the states for a long time-delay. Moreover, sequential sub-predictor method is used for robust control of dead time systems in presence of uncertainty. Simulation examples are presented to verify the proposed method.