The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We propose a ring-based quadrature LC-tank oscillator for Internet-of-Things (IoT) that can operate under a 350-mV supply voltage of energy harvesters. The oscillator is based on a series LC tank, with additional control circuitry to realize a nearly instantaneous start-up of one/two RF cycles to facilitate a deeply duty-cycled burst-mode operation of IoT. Fabricated in TSMC 28nm CMOS, the prototype...
A muti resonant controller for high-frequency-link single-phase inverter is proposed in this paper. An equivalent circuit, which behave just like conventional unipolar PWM inverter is proposed for the converter. The dynamic model of the inverter, which built in continuous domain, is built. The inverter has the advantages of high efficiency, high power density, low-cost, low noise, bidirectional power...
Both magnetic field and electric field can be used for transferring power wirelessly. But the up-to-date researches on wireless power transfer have been either inductive power transfer (magnetic field) or capacitive power transfer (electric field). An improved power transfer mode called hybrid wireless power transfer (HWPT) is proposed and evaluated in this paper. Power is transferred from primary...
This paper discusses the active and reactive power control method for a modular multilevel converter (MMC) based grid-connected PV system. The voltage vector space analysis is performed by using average value models for the feasibility analysis of reactive power compensation (RPC). The proposed double-loop control strategy enables the PV system to handle unidirectional active power flow and bidirectional...
A novel discrete sinusoidal signal integrator (DSSI) structure is proposed in this paper for single grid-tied inverters. The DSSI provides an adjustable gain and bandwidth at the expected frequency and a highly attenuated gain at other frequencies which make the DSSI based controllers obtain the zero steady-state error tracking performance of arbitrary frequencies. The performance of the conventional...
Harmonic resonance issues have been attracted more and more attention due to a large number of power electronic inverters being used in power systems. In this paper, in order to have a deep insight into resonances, the singular value sensitivities with respect to component parameters of the network and the control parameters of inverters are used for harmonic resonance analysis based on Singular Value...
A novel control strategy which enables proportional linear and nonlinear loads sharing among paralleled inverters and voltage harmonic suppression is proposed in this paper. The proposed method is based on the autonomous currents sharing controller (ACSC) instead of conventional power droop control to provide fast transient response, decoupling control and large stability margin. The current components...
Grid-connected Voltage Source Inverters (VSIs) equipped with LCL filters are attractive in utility applications for their better power quality features, while the inherent LCL resonance may limit the current control loop bandwidth or even threaten system stability. Simple but effective single-loop current control strategies have been studied for obtaining a stable system, where either the inverter-side...
In this paper, a three loop control strategy (TLCS) based on decoupled zero voltage switching angle (ZVSA) loop is proposed for a series-series (SS) compensated wireless power transmission (WPT) system. To realize constant current charging for EVs and ZVS operation of primary inverter, variable frequency and phase shift control strategy (VF-PSC) is adopted. However, the control variables that are...
The resonant stability problems of LCL filter have become big challenges for grid-connected inverter in weak grid. This paper takes the effect of non-minimum phase time delay on the ratio between resonance frequency and sampling frequency into account and use it to design the LCL filter. Both LCL resonance frequency and inverter-side inductor and filter capacitor related L1C resonance frequency are...
Current-controlled LCL-filtered inverters are usually paralleled together for interconnecting the renewable energy resources into the grid. When the inverter output impedance is not well designed, the harmonic circulating currents out of the control bandwidth may be easily aroused. To reveal this resonant phenomenon and to enhance the stability of the parallel system, this paper builds the parallel...
Applying RF circuit design techniques to dc-dc power conversion has pushed the switching frequency of power converters using discrete components beyond 100 MHz. This paper proposes a simple solution to implement synchronous rectification for resonant dc-dc power converters operating in the Very-High-Frequency (VHF) range, by using a symmetric bandpass matching network between the inverter and rectifier...
In this paper, reactive power variation based on positive feedback is proposed for improving islanding detection in the distributed generation. The proposed reactive power variation method consists of two parts, where the first part has a fundamental amplitude as +5%Pinv or −5%Pinv, and the second part has a positive feedback using a frequency deviation. Polarity and amplitude of RPV method are determined...
Capacitor-current-feedback active damping method is commonly used in LCL-filtered grid-connected inverters, which attenuates the resonance peak by emulating a virtual resistor in parallel with the filter capacitor. Taking the digital control delay into account, the emulation component becomes frequency-dependent, and it will turn negative when the filter resonance frequency becomes higher than one-sixth...
This paper presents a unified selective harmonic compensation strategy using DG-interfacing inverter with LCL filter in the presence of nonlinear local loads for both grid-connected and islanded microgrid. Compared with the existing harmonic compensation methods in the literature, the proposed strategy consists of a triple-control-loop in the grid-connected mode to compensate the grid current harmonics...
The increasing penetration of grid-connected RES systems, advanced control algorithms have been developed to operate under grid faults and fulfill strict requirements of the grid codes. In order to overcome this, the current controller performance is critical considering it as the inner control loop of any grid-connected RES system. Based on the resonant control concept, this paper presents a modified...
Harmonic resonances around the intersection frequency is triggered with the stability margin decreasing to zero and the system will be unstable with the stability margin reducing to be negative. For suppressing harmonics, the phase difference between the inverter admittance and grid admittance should be lower than 120° at their intersection. Based on this principle, a phase-reshaping strategy aiming...
Islanding detection is an essential function of distributed grid-connected power generation systems, and an islanding detection method based on adaptive reactive power disturbance is proposed in this article. Importing the reactive power disturbance can make RLC loads generate the frequency shift when the power grid is disconnected for fault and the islanding will be detected. The reactive power disturbance...
The active power filter (APF) has already established itself as a prominent means of addressing harmonic pollution and other power quality issues. Current control of an APF is a key in achieving a good compensation performance. Generally, PI control is used owing to its simplicity and ease of implementation. However, using a proportional resonant (PR) controller can give an added advantage in tracking...
In recent years, the wireless EV chargers have been spotlighted as convenient, safe, and clean apparatus. In this paper, proposed has been a newly developed large-gap wireless power transfer EV charger which can communicate control signal to a power feeding unit from a power receiving unit without any additional communication equipment. The wireless power transfer (WPT) system with a single-ended...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.