Filter Control Algorithm Research Articles

High-precision servo control design and optimization for dicing semiconductor wafer

The dicing of semiconductor wafers is an essential component for fabricating electronic circuits. A servo control approach with high-precision and stability was designed to enhance the positioning accuracy and stability for dicing semiconductor wafers. The principal control and dicing processes were studied. The High Definition closed-loop control algorithm was designed, and the control parameters were optimized. The control performance was enhanced using the PID + Feedforward + NOTCH filter control algorithm. The error detection of linear and rotation axes was designed to compensate servo axis errors by using the laser interferometer and control card. After error compensation, the positioning accuracy and repeatability of the Y-axis were 2.031 μm and 1.889 μm. That of the C-axis were 0.00423°, and 0.00347°. The dicing experiment revealed the maximum chipping width was <10 μm and the dicing channel width was <42 μm. The designed servo control system ensured the high-precision and stable dicing of semiconductor chips.

Power Quality Improvement in SyRG-PV-BES-Based Standalone Microgrid Using ESOGI-FLL-WIF Control Algorithm

In this article, a resilient enhanced second-order generalized integrator with frequency locked loop and inner loop filter (ESOGI-FLL-WIF) control algorithm is implemented to enhance the power quality and to regulate the voltage/frequency of a microgrid. This control has a simple structure, fast convergence, and excellent dynamic and steady-state response. The ESOGI-FLL-WIF control algorithm is used for assessing the fundamental constituent from harmonics and dc bias infected current. ESOGI-FLL-WIF control strategy tracks the frequency and tunes to the frequency fluctuations in transient situations. To have a fair comparison, the performance of the ESOGI-FLL-WIF control algorithm is compared with already existing controls. This three-phase four-wire islanded system consists of a solar photovoltaic array and pico-hydro turbine-driven synchronous reluctance generator (SyRG). As an alternative to the conventional generators, SyRG is used because it is economical (no permanent magnets in the rotor) and has high efficiency (no electrical losses in the rotor). The four-leg converter compensates neutral current and controls the reactive power injection under unbalance load condition, whereas for active power management, battery energy storage is incorporated in the system. A prototype of the system is developed and tested under different situations of load unbalancing and solar insolation change to confirm the effectiveness and viability of the control strategy.

Two-Vehicle Coordination System for Omnidirectional Transportation Based on Image Processing and Deviation Prediction

Omnidirectional mobile platform is essential due to its excellent mobility and versatility. With the development of the manufacturing industry, how to transport oversized or overweight goods has become a new problem. Compared with manufacturing omnidirectional mobile platforms with different specifications, it is more cost-effective and flexible to coordinate two non-physically connected omnidirectional platforms to transport overweight and oversized cargo. The roughness of the actual deployment environment and the mechanical deflection between the two vehicles have a significant impact on the normal operation of the system. This paper combines mechanical wheels, image processing algorithms and collaboration algorithms to create a novel and practical split-type omnidirectional mobile platform based on image deviation prediction for transporting oversized or overweighted goods. The proposed system collects raw measurements from a distance sensor and an image sensor, transmits them to a central processing unit through a wireless communication module and calculates and predicts the relative deflection between the two vehicles based on our derived mathematical model. This information is then fed to a Kalman filter and PID control algorithm to coordinate the two vehicles. The effectiveness and performance of our system have been thoroughly tested, which has already been applied in a bullet train production line.

Large-scaled truss topology optimization with filter and iterative parameter control algorithm of Tikhonov regularization

There are recently some advances in solving numerically topology optimization problems for large-scaled trusses based on ground structure approach. A disadvantage of this approach is that the final design usually includes many bars, which is difficult to be produced in practice. One of efficient tools is a so-called filter scheme for the ground structure to reduce this difficulty and determine several distinct bars. In detail, this technique is valuable for practical uses because unnecessary bars are filtered out from the ground structure to obtain a well-defined structure during the topology optimization process, while it still guarantees the global equilibrium condition. This process, however, leads to a singular system of equilibrium equations. In this case, the minimization of least squares with Tikhonov regularization is adopted. In this paper, a proposed algorithm in controlling optimal Tikhonov parameter is considered in combination with the filter scheme due to its crucial role in obtaining solution to remove numerical singularity and saving computational time by using sparse matrix, which means that the discrete optimal topology solutions depend on choosing the Tikhonov parameter efficiently. Several numerical examples are investigated to demonstrate the efficiency of the filter parameter control algorithm in terms of the large-scaled optimal topology designs.

A Fast Time-Domain Current Harmonic Extraction Algorithm for Power Quality Improvement Using Three-Phase Active Power Filter

Harmonic current estimation is the key aspect of Active Power Filter (APF) control algorithms to generate a reference current for harmonic compensation. This paper proposes a novel structure for harmonic current estimation scheme based on Trigonometric Orthogonal Principle (TOP) and Self Tuning Filter (STF). The key advantages of the proposed method are its simplicity, low computational burden and faster execution time in comparison to the conventional harmonic current estimation approaches. The TOP method provides a simple and fast approach to extract the reference current, while STF provides a simplified structure to generate the required synchronization signal that eliminates the need of a Phase Locked Loop (PLL) algorithm for synchronization. As a result, it exhibits less complexity in implementation and less consumption of microcontroller`s resources; thus, the proposed method can be implemented using a low-cost microcontroller. It is shown in the paper that the proposed method provides 10 times gain in processing speed as compared to the conventional DQ method. The proposed approach is analyzed in detail, and its effectiveness and superior performance are verified using simulation and experimental results.

Fluorescent Lamp Effect Correction on Capacitive Touch Panel by Timely Update Predicted Covariance Matrix

This paper proposes an adaptive Kalman filter (AKF) control algorithm for capacitive touch panels under the radiation effect of a commercial fluorescent lamp. The predicted covariance matrix of the proposed algorithm is timely updated by two-dimensional gesture compensation. It adaptively adjusts the filter correction manner between fast tracking and smoothing modes. The trajectory area and velocity concept builds up the compensation method and proves in real-time practice by a microprocessor unit. The electromagnetic radiation effect is investigated to obtain the lamp emission noise level. A comprehensive system structure provides the flexibility and efficiency in competing with different algorithms for comparison. A microprocessor unit completed the AKF method calculation in 8.23 ms under fluorescent lamp lightening condition in real time. All Python environments are implemented in the merit of hardware peripheral support, rich programming environments, and open source modules.

Digital Signal Processing in Power Electronics Control Circuits, Second Edition [Book News

This textbook has been revised and extended for its second edition (the first edition was published in 2013). It discusses problems related to the design and implementation of digital control algorithms for power electronics systems using the digital signal processing (DSP) approach. The contents of the book are organized into seven chapters: 1) “Introduction” 2) “Analog Signals Conditioning and Discretization” 3) “Selected Methods of Signal Filtration and Separation and Their Implementation” 4) “Selected Simulation Methods and Programs for Power Electronic Circuits” 5) “Selected Active Power Filter Control Algorithms” 6) “Digital Signal Processing Circuits for Digital Class-D Power Amplifier” 7) “Conclusion and Future Work.” The book opens in Chapter 2 with a discussion on the processing of analog-to-digital (A/D) signals and the most common source of errors. The author presents an overview of A/D converters suitable for power electronics control. Digital filters, multirate circuits, digital filter banks, and microcontrollers for power electronics are discussed in Chapter 3. This second edition includes a new and useful Chapter 4 that presents problems pertaining to the simulation of digitally controlled power electronic systems and includes numerous program listings in MATLAB and PSIM. The next two chapters include descriptions of selected active power filter (Chapter 5) and class-D power amplifier control algorithms (Chapter 6) as well as their implementation, simulation, and experimental results. The book concludes with a summary and a midterm forecast for future research and developments. The contents of the book are easy to read and presented in an interesting way with good illustrations. Each chapter includes an extensive list of references. This book fills a gap between power electronics and digital signal processing. I strongly recommend it to engineering educators, graduate students, and industry engineers who are interested in understanding the design of modern DSP-controlled power electronic systems.

New Control Algorithm for Single-Phase Series Active Power Filter

This article presents a single-phase series active power filter for mitigation of the load voltage harmonic content while maintaining the voltage on the DC side regulated without the support of a voltage source. The proposed series active power filter control algorithm eliminates the additional voltage source to regulate the DC voltage, and with the adopted topology, a coupling transformer is not used to interface the series active power filter with the electrical power grid. The article describes the control strategy that encapsulates the grid synchronization scheme, compensation voltage calculation, damping algorithm, and dead-time compensation. The topology and control strategy of the series active power filter have been evaluated in simulation software, and simulations results are presented. Experimental results, obtained with a developed laboratorial prototype, validate the theoretical assumptions and are within the harmonic spectrum limits imposed by the international recommendations of IEEE Standard 519.

A Novel Active Damping Control of a Three-phase PWM Inverter with LC Filter

A novel control method of a three-phase PWM inverter with LC filter is proposed. The transfer function of LC filter is the same as that of 2nd order low pass filter(2nd LPF) which has a zero damping ratio. A simple method of implementing 2nd LPF with damping ratio is to add resistor to inductor or capacitor of LC filter. In an industrial application, it is not practical to adopt damping resistor because it results in losses being proportional to square of current flowing through resistor. Instead of using damping resistors, the proposed active damping control(ADC) utilizes all pass filter(APF) and considers inherent processing delay of digital controller. The overall transfer function of the proposed method is the same as a 2nd LPF and its damping ratio is also controllable via control variables. Detailed design and implementation of controller is also presented. Experiments are conducted with a 7.5kVA induction motor drive system controlled by PWM converter and inverter. Test waveforms are also presented to verify the proposed LC filter control algorithm.

정현파 출력 필터를 가지는 3상 PWM 인버터 제어 기법

A novel control method of a three-phase PWM inverter with LC filter is proposed. The transfer function of LC filter is the same as that of second-order low pass filter(LPF) , which has a zero damping ratio. A simple method of implementing second-order LPF with damping ratio is to add a resistor in an LC circuit. However, in a real power system, adopting damping resistors is impractical because it results in losses proportional to the square of the current flowing through the resistors. Instead of inserting resistors, the proposed control strategy utilizes the measured capacitor voltages to control the oscillation of LC circuit. The overall transfer function of the proposed method is the same as a second-order LPF, and its damping ratio is controllable via control variables. The current controller can have overshoots caused by LC filter. Improved current controller is implemented by an equivalent second-order of LC filter. A 7.5 kVA PWM converter and a PWM inverter with a 5.5 ㎾ induction motor are set up to verify the proposed control algorithm. Test waveforms are also presented to verify the proposed LC filter control algorithm.

A PREDICTIVE CONTROL ALGORITHM FOR AN ACTIVE THREE-PHASE POWER FILTER

The paper deals with grid connection circuits for active filters, structures of active power filter control systems, and methods based on full capacity components determination. The existing structures of active power filter control and control algorithm adjustment for valve commutation loss reduction are analyzed. A predictive control algorithm for an active three-phase power filter is introduced.

Robotic Fish’s Movement Based on Kalman Filter and PID Control

Environmental disturbances lead to the reaction lag and precision drop of robotic fish in Chinese under-water robotic fish game. To resolve the problem, this paper proposes a new method combined Kalman filter and PID control algorithm for controlling robotic fish. The proposed approach was applied into the synchronized swimming competition of robotic fish. Simulation on two dimensional underwater robot game simulation platform shows that the method enhances the accuracy of the movement, shortens the time to the target, and improves the anti-interference ability of robotic fish. It is effective and reliable.

High-Performance Harmonic Isolation and Load Voltage Regulation of the Three-Phase Series Active Filter Utilizing the Waveform Reconstruction Method

This paper develops a waveform reconstruction method (WRM) for high accuracy and bandwidth signal decomposition of voltage-harmonic-type three-phase diode rectifier load voltage into its harmonic and fundamental components, which are utilized in the series active filter (SAF) control algorithms. The SAF-compensated system utilizing WRM provides high-performance load harmonic voltage isolation and load voltage regulation at steady-state and during transients compared to the system utilizing the synchronous reference-frame-based signal decomposition. In addition, reducing the line current sampling delay in the discrete-time implementation enhances the stability of the SAF. The simulations and experimental studies of a 10-kW three-phase SAF-compensated system prove the theory.

Instantaneous Reactive Power Theory: A Comparative Evaluation of Different Formulations

This paper analyses the behavior of different active power filter (APF) control algorithms resulting from five formulations of the instantaneous power theory: p-q original theory, d-q transformation, modified or cross product formulation, p-q-r reference frame and vectorial theory are analyzed. A simulation platform with control + APF + load is built to test the different algorithms. The results obtained in an unbalanced and nonsinusoidal three-phase four-wire system are compared. The final analysis shows that from the five formulations, only the vectorial one allows balanced and sinusoidal source currents after compensation

A DSP controlled resonant active filter for power conditioning in three-phase industrial power systems

This paper presents a DSP controlled resonant active filter for power conditioning in three-phase industrial or commercial power systems. The active filter is designed to cancel lower-order harmonics generated by nonlinear loads using a series resonant LC tank tuned to a high frequency along with a pulse-width modulated (PWM) rectifier topology. The PWM control of the active filter allows for independent control of lower-order harmonics to efficiently cancel load-generated harmonics for power quality improvement. The active filter control algorithm is simulated in MATLAB and the real-time harmonic cancellation process is implemented on a DSP and verified through experimental results.

Adaptive inverse control algorithm for shock testing

An adaptive inverse control algorithm is proposed for shock testing an arbitrary specimen using an electrodynamic actuator. The purpose is to ascertain whether the specimen can survive and continue to function under severe shock conditions. The main difficulty in shock control is that the specimen dynamics vary significantly and a control algorithm is required that adapts to the characteristics of a new specimen. The control algorithm used is the adaptive inverse control method which approximates an inverse model of the loaded shaker with a finite impulse response adaptive filter, such that the reference input is reproduced at the shaker output. The standard filtered-x least mean square control structure used in the adaptive inverse control algorithm is modified to a block-processing structure, with the frequency-domain adaptive filter as the adaptation algorithm. Practical results show that the filtered-x frequency-domain adaptive filter control algorithm allows convergence of the shaker output to the assigned reference shock pulse.