Resonant Controller Research Articles

Toward Ultrasonic Wire Bonding for High Power Device: A Vector Based Resonant Frequency Tracking and Constant Amplitude Control

The electrical packaging for high power devices such as IGBT or MOSFET is achieved by heavy aluminum ultrasonic wire bonding. In this process, the amplitude stability of ultrasonic transducer determines the bonding quality, which demands more accuracy in resonant frequency tracking (RFT) and constant amplitude control (CAC). In this investigation, we proposed a vector based resonant frequency (VRFT) tracking and vector based constant amplitude control (VCAC) to control the ultrasonic transducer. The current of dynamic branch was conducted by calculating the voltage and current vector of ultrasonic transducer. Small signal model of ultrasonic transducer was established and applied into RFT and CAC. A control strategy of fuzzy self-tuning PID closed loop was utilized to RFT and CAC. The PID parameters was calculated by the linear control theories and modified by the fuzzy controller which improved the vibration stability of the transducer. A prototype of 100Watt/60kHz ultrasonic driver was self-developed to verify the VRFT and VCAC. It demonstrated that the locked frequency of VRFT can be controlled within less than 0.04 millisecond when staring from the swept frequency, and the vibration response is fast with the varying bonding pressure. The amplitude of fuzzy PID VCAC is more stable and robust compared to the classical PID control, which improved the bonded joint quality in heavy aluminum wire packaging. Note to Practitioners—This article was motivated by the reliability and efficiency of IGBT/ MOSFET device packaging through ultrasonic aluminum wire bonding. This bonding process requires more amplitude stability of the ultrasonic transducer to achieve acceptable bonded quality. Currently, the resonant frequency tracking (RFT) by classical PID control is in slow speed, and the amplitude of the transducer cannot be controlled constantly due to the inherent static capacitor of the transducer. These issues for the ultrasonic control are originated from the engineer’s experience or simple heuristic rule instead of advanced approaches. To improve the vibration performance, we proposed a vector based model consisting of the relationship the dynamic branch current and the total current of the transducer, to control the RFT and constant amplitude control (CAC). Moreover, the vector based is utilized into the fuzzy PID control, where the calculation is reduced by area coefficient defuzzy. The verification experiments prove that the response time of the proposed vector based RFT and CAC, and the bonded joint quality is optimized obviously. It is noted that in our control strategy, the RMS value, the phase of voltage and current of the transducer are acquired by DSP processor, and the calculation of fuzzy PID controller is not complicated, which is feasible to implement in application. This significantly benefits the demand of accurate control to the ultrasonic power in electronic packaging.

Research on Harmonic Mitigation Strategy of Static VAR Generator Based on Frequency Adaptation

Offshore wind farms are integrated into the power grid via AC submarine cables, which may cause severe harmonic problems and reduce the power quality of the grid. To address the problem of excessive harmonics in offshore wind power plants (WPPs), this paper proposes a method applying the static var generator (SVG) with frequency adaptive harmonic mitigation function to the offshore WPPs. Firstly, the SVG model and the mechanism of harmonic mitigation are investigated. Secondly, the proportional and resonant control strategy is proposed according to the internal model theorem and applied to the voltage control loop of SVG. The harmonic suppression performance of SVG is studied through the Bode diagram. Thirdly, to adapt to the uncertainty of harmonic frequencies, the recursive least-squares method is introduced to realize the real-time tracking of harmonic frequencies. And the harmonic compensation bandwidth of the SVG is broadened by adjusting the parameters of the controller. Finally, the offshore WPPs in Jiangsu are built based on the Matlab/Simulink platform to verify the effectiveness of the mitigation strategy. Compared with the LC filter, the improved method can effectively mitigate (inter-) harmonics and has strong robustness and adaptability.

PROPORTIONAL INTEGRAL QUASI RESONANT CONTROLLER FOR ZERO-SEQUENCE CIRCULATING CURRENT AND RIPPLES SUPPRESSION IN PARALLEL THREE-PHASE PWM RECTIFIERS

Parallel three-phase pulse with modulation (PWM) rectifiers with common sc and ac buses are widely used in power systems due to their many advantages such as flexibility, sinusoidal grid currents, lower switching frequency, and good reliability. However, this topology suffers from zero-sequence circulating current (ZSCC) generated by numerous reasons including filters inductors unbalanced, unequal dead time, and losses of synchronism between the control of each rectifier, which will distort the ac-side currents and increase power losses. This paper proposes both an adjusted space vector pulse width modulated (ASVPWM) method and proportional integral quasi resonant controller (PIQRC) method not only to force the ZSCC to be zero but also to reduce its ripples, which results in low frequency harmonic components in the ac side currents. This twofold objective can be achieved by adjusting the zero-vector duty ratios of ASVPWM to suppress the ZSCC and by using PIQRC to mitigate its predominant harmonics. Finally, the superiority and efficiency of the proposed control method in terms of ZSCC suppression and current ripple reduction are verified through comparative analysis with the conventional ZSCC-PI controller.

Robust Adaptive Resonant Controller for PMSM Speed Regulation Considering Uncertain Periodic and Aperiodic Disturbances

This paper studies a robust adaptive resonant controller (RARC) for the speed loop of permanent magnet synchronous motor (PMSM) drives to attenuate periodic speed fluctuation of uncertain frequency. The conventional adaptive resonant controller is susceptible to the aperiodic disturbances (e.g., load torque, parameter variation, and friction torque), so it has poor robustness to the aperiodic disturbance. To solve this problem, a linear extended state observer is applied to estimate the aperiodic disturbances, and then the estimated disturbances are adapted to the adaptive resonant controller to enhance its robustness. Thus, the proposed scheme can suppress the uncertain periodic and aperiodic disturbances simultaneously. Also, the stability of the closed-loop system with the proposed scheme is analyzed by the singular perturbation theory and the averaging theorem, which can guide the tuning of control parameters. Therefore, even if there exist aperiodic disturbances, the studied RARC can also stably operate to suppress the periodic disturbance of uncertain frequency. The effectiveness of the studied RARC is validated on a 2.2-kW PMSM drive platform.

Single-phase transformerless inverter topologies at different levels for a photovoltaic system, with proportional resonant controller

<span lang="EN-US">In this paper, we have studied the topologies of single-phase transformerless inverters with different levels using a <a name="_Hlk115945664"></a>proportional-integral-resonant (PIR) AC controller, and the multi-level cascade inverter topology with sinusoidal pulse with modulation (SPWM) control in an open and closed loop. To ensure that these photovoltaic inverters can inject a defined amount of reactive power into the grid according to international regulations. Therefore, precise monitoring of the mains voltage vector by a phase-locked loop (PLL) system is applied to ensure the proper functioning of this system. For inverter topologies with less than three levels, the simulation results show that the highly efficient and reliable inverter concept (HERIC) topology performance is better than that of H5 and H6. On the other hand, the performance of the topology H6 ameliorate is superior to those of H4, H5, and HERIC in currents of leakage. On the other hand, for the control of cascaded multi-level closed-loop inverters, we notice that there is an improvement in the spectra and the elimination of all frequency harmonics, close to that of the fundamental, and a reduction in the rate of harmonic current distortion.</span>

Static-Errorless Deadbeat Predictive Current Control for PMSM Current Harmonics Suppression Based on Vector Resonant Controller

The traditional deadbeat predictive current control (DPCC) is sensitive to the unmodeled disturbances in permanent magnet synchronous motor (PMSM) drives, including alternating current (AC) and direct current (DC) disturbances, which can lead to intolerable current deviations, especially the current harmonics caused by the AC disturbance. To address the problem, a static-errorless DPCC is proposed for the current loop of PMSM drives. In the studied scheme, a vector resonant controller is used in parallel with the control law of the DPCC to compensate for the AC disturbance, while an extended state observer is used to compensate for the DC disturbance. Thus, the studied scheme is robust to both the AC and DC disturbances. The stability of the proposed scheme is systematically analyzed by the Jury criterion, while the parameter tuning is discussed in detail based on the stability analysis. Compared with the traditional DPCC, the studied scheme can effectively eliminate the current deviations to achieve static-errorless current control in PMSM drives. Finally, the effectiveness of the proposed scheme is validated on a 2.2-kW PMSM platform.

MaRCoS, an open-source electronic control system for low-field MRI

Every magnetic resonance imaging (MRI) device requires an electronic control system that handles pulse sequences and signal detection and processing. Here we provide details on the architecture and performance of MaRCoS, a MAgnetic Resonance COntrol System developed by an open international community of low-field MRI researchers. MaRCoS is inexpensive and can handle cycle-accurate sequences without hard length limitations, rapid bursts of events, and arbitrary waveforms. It has also been readily adapted to meet the requirements of the various academic and private institutions participating in its development. We describe the MaRCoS hardware, firmware and software that enable all of the above, including a Python-based graphical user interface for pulse sequence implementation, data processing and image reconstruction.

Comparison of Control Techniques for Harmonic Isolation in Series VSC-Based Power Flow Controller in Distribution Grids

The application of power electronics equipment in medium voltage (MV) distribution grids can provide new management solutions for power flow control, load balancing and voltage problems. A series MV VSC-based power flow controller has recently been presented to interconnect two radial distribution feeders performing active and reactive power transfers to improve the flexibility and utilization of these circuits in a controlled and secure way. Although not previously explored, this power flow controller can integrate the functionality of a series power filter, accomplishing independent control of the fundamental power flow while isolating the harmonic content between the two interconnected feeders. This prevents harmonic pollution from one feeder from propagating to the other, improving the voltage quality. To implement the harmonic isolation, several control strategies can be used. Therefore, this paper provides a comparative analysis between two of the main harmonic control techniques found in the literature: the Synchronous Reference Frame (SRF) controller and the Proportional Resonant (PR) controller. Assessments are conducted both through simulations and experimental results in a meshed network at 13.8 kV with different types of non-linear loads. In the simulation cases, both algorithms showed similar results; however, in the experimental cases, the PR-based solution exhibited better performance in isolating the harmonics from one feeder to the other.

Research on complex vector quasi-resonant control methods for permanent magnet synchronous motor

A complex vector quasi-resonant controller is proposed to solve the current controller’s dynamic coupling problem and static harmonics. Although current feedforward decoupling has been widely used, the calculation relies on the motor parameters. When the motor works at high speed and high torque load, the parameters change greatly, failing to decouple. In the static conditions, due to the inverter nonlinearity, the PMSM stator current contains lots of high harmonics, which causes the motor produces a specific frequency torque ripple. Therefore, complex vector quasi-resonance is proposed. The complex vector transfer function contains a virtual axis zero point, which varies with speed so that the zero point of the controller and the pole of the controlled object are eliminated. The quasi-resonant controllers are connected in parallel with the main controller and suppress harmonics at fixed frequencies of the system. The method is based on the resonant controller with infinite gain at the resonant frequency point, which can achieve zero steady-state error tracking, achieving the purpose of torque pulsation suppression. In this paper, through theoretical derivation and algorithm structure design, the algorithm’s effectiveness is verified in the simulation. The proposed algorithm has a fast response in the dynamic state and smaller current harmonics in the steady state.

Precise Position Control Based on Resonant Controller and Second-Order Sliding Mode Observer for PMSM-Driven Feed Servo System

Precise position control and smooth feed speed are important research areas for permanent magnet synchronous motor (PMSM) driven computerized numerical control (CNC) servo feed systems, but it suffers from aperiodic disturbances caused by unmodeled dynamics, system parameter perturbations, variable cutting force and periodic disturbances caused by the current sampling error, aperiodic disturbances, and periodic disturbances that reduce the positional accuracy of the CNC feed servo. To address the problem, a control scheme is proposed for the position controller to suppress the disturbances. In the control scheme, the second-order sliding mode disturbance observer (SSMDO) is proposed to estimate and compensate for the aperiodic disturbances, and the resonant controller (RC) with phase adjustable is designed to suppress the periodic disturbances. The stability and antidisturbance capability of the studied scheme are analyzed systematically, and the flow of controller design and parameter tuning is presented considering the overall system. The proposed RC combined with SSMDO (RC-SSMDO) scheme can effectively alleviate the position tracking error and feed steady-state speed ripple, which is suitable for the actual working conditions of the CNC feed servo system. Experiment results confirm the validity of the proposed scheme.

Analysis of Grid-Connected VSCs Subject to Voltage Harmonic Disturbances: Prediction and Design Tool of Resonant Controllers

The influence of current and voltage harmonics in the power quality of electrical facilities is currently an important topic in discussion. Considering that in Voltage Source Converter (VSC) applications it is common to utilize resonant controllers to mitigate characteristic current harmonics, this work proposes a methodology to allow the tuning of resonant controllers through a power quality criterion during the design process, enabling the designer to select between harmonic content and stability. The disturbance rejection model that relates the output harmonic currents with the grid voltage harmonics is utilized as basis for the methodology, also providing an analytical calculation of the resonant controller gain according to the imposed harmonic limitations, both for VSCs with regular L as with LCL output filters. Simulations and experiments validate the proposal.

Mitigation of Oscillations in Three Phase LCL-Filtered Grid Converters Based on Proportional Resonance and Improved Model Predictive Control

For three phase <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCL</i> -filtered gird converters, this paper designs a robust control strategy to reduce high frequency and subsynchronous or supersynchronous oscillations. Two components, namely the grid side inductor component and the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> filter component, constitute a three phase <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCL</i> -filtered grid converter. Model predictive control (MPC) with a disturbance observer is used to control the interconnection voltage of the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> filter. Proportional resonance (PR) control regulates the grid side current. It is possible to combine MPC with PR's advantages. The dynamic performance is enhanced by MPC's intrinsic ability to achieve active damping without extra control and reduce modulation latency. In addition to achieving zero steady state error, PR control greatly simplifies the control process when compared to the overall MPC of the entire grid converter. By analyzing the frequency response of the transfer function and output impedance, it is possible to determine that the proposed control has a sufficient phase margin and that, even when the system and control parameters change, the grid converters’ output impedance is always resistive or inductive at the entire frequency, suppressing subsynchronous and high frequency oscillations. To further reduce the oscillations and harmonics, an improved MPC control framework and a feedback compensation mechanism are proposed. The effectiveness and reliability of the proposed control in current tracking, harmonic suppression, and response to grid impedance variations are verified by comparative analysis of simulation results.

Resonance control method to suppress the self and mutual inductances of a 3-phase magnetic navigation system for fast drilling motion of micro helical robots

We developed a resonance control method to generate a high-speed rotating magnetic field in a three-phase magnetic navigation system composed of three electromagnets. The proposed resonance control method calculates the amplitudes and phases of voltages, while the capacitances suppressing the self and mutual inductances of the electromagnets to keep the currents and the magnitude of the rotating magnetic field constant, even if the frequency of the rotating magnetic field increases. Finally, we prototyped the three-phase magnetic navigation system and the variable capacitor module to validate the effectiveness of the proposed resonance control method experimentally.

Enhanced Protection Coordination for Inverter Interfaced Distributed Generation (IIDG) with a Robust Multi-Loop Controller

Increasing penetration of inverter interfaced distributed generation (IIDG) in distribution networks has severely impacted protection coordination. False tripping, sympathetic tripping, protection blinding, failure of reclosing, and increase in short circuit levels are the critical complications and consequently disturbed the protection setting of the distribution network. This paper presents a novel multiloop current control scheme based on single integrator backstepping with a proportional resonant (PR) controller assisted by the whale optimization algorithm (WOA) to integrate IIDG in the distribution network. This control approach is designed to mitigate the maloperation of the overcurrent protection, due to the IIDG's current contribution during various types of faults. Inner loop backstepping is utilized to track converter side current and in addition, the PR controller is designed to track grid current in an outer loop. Using the proposed methodology, the injected current to the grid is effectively controlled to the rated level during several types of faults or disturbances. The performance of the proposed control strategy is verified by time-domain results and through eigenvalues trajectory and results have been compared with a current state-of-the-art which corroborates the effective control capability of the present controller.

High Precision Sinusoidal Position Tracking of a Voice-Coil Linear Servomotor Using Resonant Control

This paper presents a new sinusoidal position-tracking control scheme with a resonant controller for linear motor drive systems. The sinusoidal tracking controller is designed without any added algorithm for system identification and requires only approximate values of the mechanical parameters. Therefore, the controller is simple and robust to parameter variations. The proposed sinusoidal tracking resonant-based controller (STRC) is designed to track reference positions using a cascade control structure with an inner current/force control with hysteresis current control followed by a speed control loop with a resonant controller, and an outer position loop with a proportional and velocity-feedforward controller. The stability of the cascade feedback scheme and its parameter tuning are analyzed using the Routh–Hurwitz criterion. The performance of the proposed control scheme is validated using simulations and experiments on a voice-coil linear stage. The proposed STRC strategy is characterized by ease of implementation and shows excellent performance with fast response and high accuracy at different frequencies with a maximum error of 0.58% at 0.25 Hz.

Consensus-Based Intelligent Distributed Secondary Control for Multiagent Islanded Microgrid

Isolated microgrids (MGs) face challenges in performance stability and active/reactive power sharing as a result of frequency/voltage deviations and mismatched line impedance issues. In this paper, a consensus-based multiagent system (MAS) is proposed as a solution to restore voltage/frequency deviations and enable true power sharing. The invention of an Intelligent Distributed Secondary Control Scheme (IDSCS) can efficiently achieve hoped-for outcomes. The proposed IDSCS features estimation and compensation sublayers. For the estimation sublayer, discrete dynamic consensus algorithm-based state estimators are presented to collect average information of frequency, voltage, and reactive power. Each DG is viewed as an agent sharing information with its immediate neighbors through a sparse cyber communication network. In the compensation sublayer, online tuned proportional integral (PI) controllers using artificial neural networks (ANNs) are proposed as an intelligent voltage and frequency compensators. This combination uses the simplicity of the PI controller mathematical formula and ANN’s ability to deal with parameter variations and nonlinearity. Due to the global nature of the frequency parameter, the active power-sharing compensator is unnecessary. For compensating reactive power deviations, ANNs-based reactive power controllers are proposed. Furthermore, at the primary control level, the proposed strategy employs discrete-time proportional resonant (PR) controllers in a stationary reference frame, eliminating the need for any α β / d q or d q / α β transformations. Distributed implementation of the proposed method guarantees system scalability without MG topology or demand pattern expertise. The control scheme was validated using hypothetical MAS in MATLAB Simulink platform. The simulation findings indicate the proposed MG system can effectively distribute power among the DGs while maintaining voltage and frequency stable.

Backstepping-Based Direct Power Control for Dual-Cage Rotor Brushless Doubly Fed Induction Generator

In this article, we propose a backstepping (BS)-based direct power control (DPC) strategy for the dual-cage rotor brushless doubly fed induction generator (DCR-BDFIG). The relationship between the power winding (PW) output power and the control winding (CW) voltage is derived according to the complete mathematical model of DCR-BDFIG. Based on that, a BS-based DPC controller, also known as a nonlinear controller, is designed with the global asymptotic stability analyzed for the grid-connected DCR-BDFIG. Compared with the dual-closed-loop control in the advanced vector control method, only single-closed-loop is required for the PW power in the proposed BS-based control scheme, and thus it has more simple structure and faster responses. The global stability of the proposed control scheme can be easily guaranteed with a Lyapunov function properly selected. In addition, in order to improve the performance of the proposed BS-based DPC strategy under unbalanced network, the resonant controller is introduced to suppress the oscillating components in the PW power, PW current, and CW current, whose harmonic order is twice of the grid frequency referring to the synchronous reference frame. Finally, the detailed experimental results demonstrate the effectiveness of the proposed control strategy.

Adaptive quasi-proportional resonant control with parameter estimation for PMSM sensorless control

Conventional sliding mode control (SMO) utilizes a sign function and a low-pass filter (LPF) to achieve sensorless control of a permanent magnet synchronous motor (PMSM). However, the introduction of the sign function generates a large number of high harmonics, resulting in a significant system output chattering, whereas the addition of the LPF generates control delays and phase shifts. These degrade the PMSM speed and the position estimation accuracy and reduce the system control performance. To improve the performance of the PMSM, adaptive quasi-proportional resonant sensorless control with parameter estimation (AQPR_PE) is proposed. In this control model, an adaptive quasi-proportional resonance controller is used reduce the system output error and to weaken the chattering phenomenon. Meanwhile, the system PMSM parameters are estimated online and fed back to the control model to improve the system parameter robustness and the control accuracy. The Bode diagram, Popov theory, and root trajectory are used to analyze the stability of AQPR, parameter estimation, and AQPR_PE, respectively. Finally, the effectiveness of the proposed method is demonstrated by experimental validation.

Investigation on self-sensing monitoring and resonant control of ultrasonic vibration–assisted cutting

Investigation on self-sensing monitoring and resonant control of ultrasonic vibration–assisted cutting

Sliding Mode Control for Single-Phase Grid-Connected Voltage Source Inverter with L and LCL Filters

This paper presents an analysis of the sliding mode control (SMC) method applied to a single-phase grid-connected voltage source inverter (VSI) with L and LCL filters. First, simulation results were presented for the L filter, and then, after some adjustments, the same theory was applied to the LCL VSI with active damping. To improve the obtained results for the SMC control, we adopted the hyperbolic tangent function and the explicit establishment of the modulation index m in the mathematical procedure to help reduce the chattering phenomena; later on, the same function was replaced by the usage of a proportional plus resonant controller to continuously improve the control system responses.