Showing papers on "Rectifier published in 2005"
TL;DR: This work presents the state of the art in the field of regenerative rectifiers with reduced input harmonics and improved power factor, showing that PWM regenerativerectifiers are a highly developed and mature technology with a wide industrial acceptance.
Abstract: New regulations impose more stringent limits on current harmonics injected by power converters that are achieved with pulsewidth-modulated (PWM) rectifiers. In addition, several applications demand the capability of power regeneration to the power supply. This work presents the state of the art in the field of regenerative rectifiers with reduced input harmonics and improved power factor. Regenerative rectifiers are able to deliver energy back from the dc side to the ac power supply. Topologies for single- and three-phase power supplies are considered with their corresponding control strategies. Special attention is given to the application of voltage- and current-source PWM rectifiers in different processes with a power range from a few kilowatts up to several megawatts. This paper shows that PWM regenerative rectifiers are a highly developed and mature technology with a wide industrial acceptance.
831 citations
TL;DR: A rectifier based on a pentacene diode that can rectify an incoming a.c. signal at 50 MHz is reported, showing that even the ultra-high-frequency band at around 800 MHz is within reach.
Abstract: Amain focus of research on organic semiconductors is their potential application in passive organic radio-frequency identification (RF-ID) tags. First prototypes working at 125 kHz have been shown by industrial research groups1. However, to be commercially viable, the organic RF-ID tag would need to be compatible with the base-carrier frequency of 13.56 MHz (ref. 2). High-frequency operation has been out of reach for devices based on organic semiconducting material, because of the intrinsically low mobility of those materials. Here, we report on a rectifier based on a pentacene diode that can rectify an incoming a.c. signal at 50 MHz. At 14 MHz, a rectified voltage of 11 V for an a.c. voltage with a peak-to-peak amplitude of 36 V has been achieved. On the basis of those results, we estimate the frequency limits of an organic diode showing that even the ultra-high-frequency band at around 800 MHz is within reach.
250 citations
TL;DR: A novel extension of the 12-pulse rectifier system by turn-off power semiconductors is proposed which allows a control of the output voltage and, therefore, eliminates the dependency on the mains and load condition which constitutes a main drawback of the passive concept.
Abstract: A passive 12-pulse rectifier system, a two-level, and a three-level active three-phase pulsewidth-modulation (PWM) rectifier system are analyzed for supplying the dc-voltage link of a 5-kW variable-speed hydraulic pump drive of an electro-hydrostatic actuator to be employed in future More Electric Aircraft. Weight, volume, and efficiency of the concepts are compared for an input phase voltage range of 98-132 V and an input frequency range of 400-800 Hz. The 12-pulse system shows advantages concerning volume, efficiency, and complexity but is characterized by a high system weight. Accordingly, the three-level PWM rectifier is identified as the most advantageous solution. Finally, a novel extension of the 12-pulse rectifier system by turn-off power semiconductors is proposed which allows a control of the output voltage and, therefore, eliminates the dependency on the mains and load condition which constitutes a main drawback of the passive concept.
236 citations
TL;DR: The design procedure starts with the formation of equivalent circuits, followed by the analysis of the loss of the rectifier and coils and the H-field for induced voltage and current and an experimental power link is implemented with an overall efficiency of 67% at the optimal distance of 7 mm between the coils.
Abstract: This paper presents a design methodology of a highly efficient power link based on Class-E driven, inductively coupled coil pair. An optimal power link design for retinal prosthesis and/or other implants must take into consideration the allowable safety limits of magnetic fields, which in turn govern the inductances of the primary and secondary coils. In retinal prosthesis, the optimal coil inductances have to deal with the constraints of the coil sizes, the tradeoffs between the losses, H-field limitation and dc supply voltage required by the Class-E driver. Our design procedure starts with the formation of equivalent circuits, followed by the analysis of the loss of the rectifier and coils and the H-field for induced voltage and current. Both linear and nonlinear models for the analysis are presented. Based on the procedure, an experimental power link is implemented with an overall efficiency of 67% at the optimal distance of 7 mm between the coils. In addition to the coil design methodology, we are also presenting a closed-loop control of Class-E amplifier for any duty cycle and any value of the systemQ.
233 citations
TL;DR: A linear two-port model for an N-stage modified-Greinacher full-wave rectifier that predicts the overall conversion efficiency at low power levels where the diodes are operating near their threshold voltage is proposed.
Abstract: This paper proposes a linear two-port model for an N-stage modified-Greinacher full-wave rectifier. It predicts the overall conversion efficiency at low power levels where the diodes are operating near their threshold voltage. The output electrical behavior of the rectifier is calculated as a function of the received power and the antenna parameters. Moreover, the two-port parameter values are computed for particular input voltages and output currents for the complete N-stage rectifier circuit using only the measured I-V and C-V characteristics of a single diode. To validate the model a three-stage modified-Greinacher full-wave rectifier was realized in an silicon-on-sapphire (SOS) CMOS 0.5-/spl mu/m technology. The measurements are in excellent agreement with the values calculated using the presented model.
190 citations
TL;DR: In this article, an active damping control method is proposed for the reduction in line current THD of high-power current-source rectifiers operating at a switching frequency of only 540 Hz.
Abstract: The use of active damping to reduce the total harmonic distortion (THD) of the line current for medium-voltage (2.3-7.2 kV) high-power pulsewidth-modulation (PWM) current-source rectifiers is investigated. The rectifier requires an LC filter connected at its input terminals, which constitutes an LC resonant mode. The lightly damped LC filter is prone to series and parallel resonances when tuned to a system harmonic either from the utility or from the PWM rectifier. These issues are traditionally addressed at the design stage by properly choosing the filter resonant frequency. This approach may result in a limited performance since the LC resonant frequency is a function of the power system impedance, which usually varies with power system operating conditions. In this paper, an active damping control method is proposed for the reduction in line current THD of high-power current-source rectifiers operating at a switching frequency of only 540 Hz. Two types of LC resonances are investigated: the parallel resonance excited by harmonic currents drawn by the rectifier and the series resonance caused by harmonic pollution in the source voltage. It is demonstrated through simulation and experiments that the proposed active damping control can effectively reduce the line-current THD caused by both parallel and series resonances.
175 citations
Patent•
21 Jul 2005
TL;DR: In this article, a ripple percentage reducing circuit is proposed to reduce the ripple percentage of a ripple current that flows into a smoothing capacitor provided at the down-stream side of a rectifier circuit.
Abstract: PROBLEM TO BE SOLVED: To provide a switching power supply provided with what is called a ripple percentage reducing circuit that effectively reduces the ripple percentage of a ripple current that flows into a smoothing capacitor provided at the down-stream side of a rectifier circuit. SOLUTION: This switching power supply is of a DC indirect conversion type provided with the rectifier circuit and the smoothing capacitor positioned at the post-stage of the rectifier circuit at the secondary side of a transformer. A ripple reducing coil is connected in series to the pre-stage line of the smoothing capacitor, the line at a position where a current is inputted into or outputted from the rectifier circuit. COPYRIGHT: (C)2005,JPO&NCIPI
172 citations
Patent•
12 Sep 2005TL;DR: In this article, a synchronous full bridge rectifier with PFC is presented to provide a power factor near unity with respect to the AC input signal and currents within the circuit.
Abstract: A synchronous full bridge rectifier is controlled to provide a power factor near unity The full bridge rectifiers are transistors each with a controlling input The AC input signal and currents within the circuit are sensed and sent to a controller In response, the controller output control signals to turn on/off the rectifying MOSFETS on a timely basis to form a power factor of near one with respect to the AC input signal The full wave rectifier is made of N-channel MOSFET's, some with fast body diodes The MOSFET's are rectifiers and PFC control elements The result is a one stage synchronous rectifier with PFC A solid state precision analog differential amplifier senses the AC line waveform and high frequency current transformers sense the currents The controller accepts the inputs of the amplifier and the sensed currents and outputs control signals that turn on and off the four MOSFET's The timing of turning on/off is arranged so that the current drawn from the AC source is sinusoidal and matches the phase of the sinusoidal AC source
158 citations
TL;DR: A system comparison is developed between thyristor and chopper-rectifiers in terms of quality of control, harmonics, power factor, losses, and efficiency, and the most important requirements and specifications to be considered in the applications of these high-power units.
Abstract: This paper presents the different technologies used in the generation of large controlled currents, in the kiloamperes range. After a brief review of processes requiring large currents, the paper discusses the working principles of thyristor phase-controlled rectifiers commonly used in these applications. Chopper-rectifiers using high-current insulated gate bipolar transistors are introduced as an alternative being considered in recent projects. The pulsewidth-modulated current-source rectifier, currently used in medium-voltage motor drives, is also analyzed as a future alternative for rectification in industrial processes. In addition, this paper presents the most important requirements and specifications to be considered in the applications of these high-power units. A system comparison is developed between thyristor and chopper-rectifiers in terms of quality of control, harmonics, power factor, losses, and efficiency.
148 citations
TL;DR: Thanks to the idea of virtual flux, the direct power control space-vector-modulated (DPC-SVM) and new synchronous double reference frame phase-locked loop approach, the control system is resistant to a majority of line voltage disturbances.
Abstract: Slight hardware and algorithm modifications as well as a higher power ratio of a three-phase pulsewidth-modulation (PWM) rectifier make compensation of neighboring nonlinear power load possible. The active filtering function enlarges the functionality of PWM rectifiers, which decreases the cost of additional installation of compensating equipment. It gives a chance to fulfill both shunt active filter (SAF) and PWM rectifier tasks in a multidrive system by one advanced converter. Thanks to the idea of virtual flux, the direct power control space-vector-modulated (DPC-SVM) and new synchronous double reference frame phase-locked loop approach, the control system is resistant to a majority of line voltage disturbances. This assures proper operation of the system for abnormal and failure grid conditions. Simulation and experimental results have proven excellent performance and verify the validity of the proposed system.
145 citations
TL;DR: In this article, the authors proposed a novel control strategy and a protection circuit and showed the advantage of utilizing a newly developed reverse blocking insulated gate bipolar transistor (RB-IGBT) to solve several practical problems of the matrix converter.
Abstract: This paper proposes a novel control strategy and a protection circuit and shows the advantage of utilizing a newly developed reverse blocking insulated gate bipolar transistor (RB-IGBT), to solve several practical problems of the matrix converter. The proposed control strategy is based on a virtual indirect control method with a virtual rectifier and a virtual inverter. Pulse-width modulated (PWM) pulses for the matrix converter are obtained by combining PWM pulses for the virtual rectifier and inverter. As a result, the control part of the input current and output voltage can be clearly separated. Thus, the conventional inverter control algorithms can be applied to the virtual inverter control. The advantage of this method is confirmed by experimental results with a 22-kW induction motor drive system. Good sinusoidal waveforms are obtained for the input and output currents, and the total harmonic distortion (THD) of the input and output current are 5.1% and 1.4%, respectively. The conduction loss of the RB-IGBT is decreased to about two-thirds of the conventional ac switch with series connection diode. Thus, the converter loss is about a half to the conventional PWM rectifier-inverter system with the same capacity. Furthermore, the protection problem is solved by a dynamic clamp method without an electrolytic capacitor. This protection circuit directly dissipates reactive load energy by dynamic clamp operation of an IGBT.
TL;DR: In this paper, a family of inductor-less bus converters is proposed to overcome the limitations of current bus transformers, where magnetizing current is used to achieve zero-voltage-switching (ZVS) turn-on for all switches.
Abstract: This paper begins by reviewing current bus converters and exploring their limitations. Next, a family of inductor-less bus converters is proposed to overcome the limitations. In the new bus converters, magnetizing current is used to achieve zero-voltage-switching (ZVS) turn-on for all switches. The resonant concept is used to achieve nearly zero-current-switching (ZCS) turn-off for the primary switches and no body diode loss for the synchronous rectifiers (SRs). Meanwhile, the self-driven method can be easily applied to save drive loss of SRs. Based on these concepts, a full-bridge bus converter is built in the quarter-brick size to verify the analysis. The experimental results indicate that it can achieve 95.5% efficiency at 500-W, 12-V/45-A output. Compared with industry products, this topology can dramatically increase the power density. These concepts are also applied to nonisolated dc/dc converters. As an example, a resonant Buck converter is proposed and experimentally demonstrated.
Patent•
24 Mar 2005
TL;DR: In this article, a three-stage power source for an electric arc welding process is presented, consisting of an input stage having an AC input and a first DC output signal; a second stage in the form of an unregulated DC to DC converter having an input connected to the first AC output signal, a network of switches switched at a high frequency with a given duty cycle to convert the input into a first internal AC signal, an isolation transformer with a primary winding driven by the first internal high frequency AC signal and a secondary winding for creating a second internal high-frequency AC signal of the second
Abstract: A three stage power source for an electric arc welding process comprising an input stage having an AC input and a first DC output signal; a second stage in the form of an unregulated DC to DC converter having an input connected to the first DC output signal, a network of switches switched at a high frequency with a given duty cycle to convert the input into a first internal AC signal, an isolation transformer with a primary winding driven by the first internal high frequency AC signal and a secondary winding for creating a second internal high frequency AC signal and a rectifier to convert the second internal AC signal into a second DC output signal of the second stage, with a magnitude related to the duty cycle of the switches; and, a third stage to convert the second DC output signal to a welding output for welding wherein the input stage has a regulated DC to DC converter with a boost power switch having an active soft switching circuit.
TL;DR: A current control method based on a sinusoidal internal model is employed, which uses a sine transfer function with a specified resonant frequency and a combination of a conventional proportional-integral (PI) regulator and an S regulator, called a PIS regulator.
Abstract: Three-phase voltage-source converters are used as utility interfaces. In such a case, the converter line currents are required to track sinusoidal references synchronized with the utility grid without a steady-state error. In this paper a current control method based on a sinusoidal internal model is employed. The method uses a sine transfer function with a specified resonant frequency, which is called an S regulator. The combination of a conventional proportional-integral (PI) regulator and an S regulator is called a PIS regulator. The PIS regulator ensures that the steady-state error in response to any step changes in a reference signal at the resonant frequency and 0 Hz reduces to zero. An experiment was carried out using a 1-kVA prototype of three utility-interface converters, a voltage-source rectifier, an active power filter, and static synchronous compensator. Almost perfect current-tracking performance could be observed.
Patent•
11 Jan 2005TL;DR: In this article, a complementary SCR-based structure enables a tunable holding voltage for robust and versatile ESD protection, which makes possible the use of this protection circuit in a broad range of ESD applications including protecting integrated circuits.
Abstract: A complementary SCR-based structure enables a tunable holding voltage for robust and versatile ESD protection. The structureare n-channel high-holding-voltage low-voltage -trigger silicon controller rectifier (N-HHLVTSCR) device and p-channel high-holding-voltage low-voltage -trigger silicon controller rectifier (P-HHLVTSCR) device. The regions of the N-HHLVTSCR and P-HHLVTSCR devices are formed during normal processing steps in a CMOS or BICMOS process. The spacing and dimensions of the doped regions of N-HHLVTSCR and P-HHLVTSCR devices are used to produce the desired characteristics. The tunable HHLVTSCRs makes possible the use of this protection circuit in a broad range of ESD applications including protecting integrated circuits where the I/O signal swing can be either within the range of the bias of the internal circuit or below/above the range of the bias of the internal circuit.
Patent•
19 Apr 2005TL;DR: An integrated torsional mode damping method for a current source converter, including a rectifier, an inverter and a DC link inductor coupled between the rectifier and the inverter, was proposed in this paper.
Abstract: An integrated torsional mode damping method for a current source converter, including a rectifier, an inverter, and a DC link inductor coupled between the rectifier and the inverter, includes sensing a signal representative of torque on a shaft coupled to the inverter or rectifier; using the sensed signal for detecting a presence of a torsional vibration on the shaft; and damping the torsional vibration by modulating active power through the respective inverter or rectifier.
TL;DR: The main evaluation aspects are input filter size, semiconductor losses, maximum switching frequency, part count, initial cost, and life cycle cost.
Abstract: This paper evaluates the benefits of three-level topologies as alternatives to two-level topologies in low-voltage converters primarily operated in rectifier mode. The main evaluation aspects are input filter size, semiconductor losses, maximum switching frequency, part count, initial cost, and life cycle cost. Semiconductor loss characteristics of various three-level topologies are discussed. A detailed converter comparison is based on a 100-kW 400-V/sub rms/ rectifier using commercially available Si insulated gate bipolar transistor modules.
TL;DR: In this article, a comprehensive control strategy that addresses all three control objectives in a wind generation system, i.e., control of the local bus voltage to avoid voltage rise, capture of the maximum power in the wind and minimization of the power loss in the induction generator is proposed.
Abstract: A comprehensive control strategy, that addresses all three control objectives in a wind generation system, i.e. control of the local bus voltage to avoid voltage rise, capture of the maximum power in the wind and minimization of the power loss in the induction generator is proposed. The control signals are the desired current wave shapes (instantaneous three-phase currents) of the rectifier and the inverter in a double-sided PWM converter system connected between the wind generating unit and the grid. Studies performed on a complete model for a variable speed cage machine wind generation unit, including wind profile, wind turbine, induction generator, PWM converter, local load and transmission line, show that even as the wind speed changes randomly, the proposed control strategy leads the system to the optimum operating conditions.
TL;DR: A new single-phase high power factor rectifier, which features regulation by conventional PWM, soft commutation and instantaneous average line current control is proposed, which uses a single converter instead of the conventional configuration composed of a four-diode front-end rectifier followed by a boost converter.
Abstract: This paper proposes a new single-phase high-power-factor rectifier, which features regulation by conventional pulsewidth modulation (PWM), soft commutation, and instantaneous average line current control. A new zero-voltage-switching PWM (ZVS-PWM) auxiliary circuit is configured in the presented ZVS-PWM rectifier to perform ZVS in the main switches and the passive switches, and zero-current switching in the auxiliary switch. Furthermore, soft commutation of the main switch is achieved without additional current stress by the presented ZVS-PWM auxiliary circuit. A significant reduction in the conduction losses is achieved, since the circulating current for the soft switching flows only through the auxiliary circuit and a minimum number of switching devices are involved in the circulating current path, and the proposed rectifier uses a single converter instead of the conventional configuration composed of a four-diode front-end rectifier followed by a boost converter. Nine transition states for describing the behavior of the ZVS-PWM rectifier in one switching period are described. A prototype rated at 1 kW, operating 80 kHz, with an input ac voltage of 220 V/sub rms/ and an output voltage of 400 V/sub dc/ has been implemented in the laboratory. An efficiency of 96.7% and power factor over 0.99 has been measured. Analysis, design, and the control circuitry are also presented in this paper.
01 Jan 2005
TL;DR: A bi-directional power converter used on one hand as a battery charger and on the otherHand as a motor speed controller is presented and a comparison of these structures is carried out.
Abstract: This paper presents a bi-directional power converter used on one hand as a battery charger and on the other hand as a motor speed controller. Different possibilities are presented and a comparison of these structures is carried out. In battery charger mode, the power converter has to absorb a sinusoidal current with a unit power factor. According to the power range, two possibilities are presented: the isolated CUK converter with a 1.5 kW DC motor and a pulse width modulation (P.W.M.) inverter/rectifier to supply a 6 kW induction machine
TL;DR: An improvement of the well-known conventional three-phase diode bridge rectifier with dc output capacitor with capacitive smoothing which increases the power factor at the ac input and reduces the ripple current stress on the smoothing capacitor.
Abstract: This paper presents an improvement of the well-known conventional three-phase diode bridge rectifier with dc output capacitor. The proposed circuit increases the power factor (PF) at the ac input and reduces the ripple current stress on the smoothing capacitor. The basic concept is the arrangement of an active voltage source between the output of the diode bridge and the smoothing capacitor which is controlled in a way that it emulates an ideal smoothing inductor. With this the input currents of the diode bridge which usually show high peak amplitudes are converted into a 120/spl deg/ rectangular shape which ideally results in a total PF of 0.955. The active voltage source mentioned before is realized by a low-voltage switch-mode converter stage of small power rating as compared to the output power of the rectifier. Starting with a brief discussion of basic three-phase rectifier techniques and of the drawbacks of three-phase diode bridge rectifiers with capacitive smoothing, the concept of the proposed active smoothing is described and the stationary operation is analyzed. Furthermore, control concepts as well as design considerations and analyses of the dynamic systems behavior are given. Finally, measurements taken from a laboratory model are presented.
TL;DR: The use of a passivity-based control (PBC) designed via energy considerations and without small-signal linearization properly fits stability problems related to this type of converter and the system dc buses are independent and stable as experimental results demonstrate.
Abstract: This paper deals with the control of a multilevel n-H-bridges front-end rectifier. This topology allows n distinct dc buses to be fed by the same ac source offering a high loading flexibility suitable for traction applications as well as for industrial automation plants. However, this flexibility can lead the system to instability if the dc buses operate at different voltage levels and with unbalanced loads. Thus, linear controllers, designed on the basis of the small-signal linearization, are not effective any longer and stability can not be ensured as large-signal disturbances occur. The use of a passivity-based control (PBC) designed via energy considerations and without small-signal linearization properly fits stability problems related to this type of converter. The system has been split into n subsystems via energy considerations in order to achieve the separate control of each dc bus and its stability in case of load changes or disturbances generated by other buses. Then, a set of n passivity-based controllers (one for each subsystem) is adopted: the controllers are linked using dynamical parameters computed through energy balance equations. Hence, the system dc buses are independent and stable as experimental results demonstrate.
TL;DR: In this paper, a self-driven zero-voltage switching (ZVS) full-bridge converter is proposed, which makes use of the input capacitor of the secondary side synchronous rectifier (SR) as the snubber capacitor of primary side switches.
Abstract: In this paper, a self-driven zero-voltage-switching (ZVS) full-bridge converter is proposed. With the proposed self-driven scheme, the combination of the ZVS technique and Self-driven technique recycles the gate driving energy by making use of the input capacitor of the secondary side synchronous rectifier (SR) as the snubber capacitor of the primary side switches. Compared with the external driver, the proposed converter can save driving loss and synchronous rectifier body diode conduction loss. Additionally, compared with the existed level-shifted self-driven scheme for bridge-type symmetrical topologies, its gate signal is very clean and suitable for high-frequency applications. A 1-MHz, 1.2-V/70-A prototype is built to verify the analysis. Experimental results show that it can achieve 81.7% efficiency. And there is an efficiency improvement of 4.7% over conventional phase-shifted full-bridge converter with an external driver.
TL;DR: In this article, a dual stator-winding induction generator (DWIG) system is built, where two sets of windings are embedded in the stator slots to reduce inductance of rectifier loads and help to reduce capacitance of the SER.
Abstract: On the basis of the new idea of electric power integration, a novel stand-alone dual stator-winding induction generator (DWIG) system is built. In this generator, there are two sets of windings to be embedded in the stator slots. One, referred to as the 12-phase power winding, supplies power to the dc load via a 12-phase bridge rectifier, and the other, called the 3-phase excitation winding, is connected to a pulsewidth modulation (PWM) voltage source static excitation regulator (SER). A solid iron squirrel cage rotor is suitable for high speed generation. Experiments and simulations show the ac capacitors can reduce the inductance of rectifier loads and help to reduce the capacitance of the SER. A simple control methodology based on stator voltage orientation (SVO) is presented to regulate the output voltage of the 12-phase bridge rectifier in this paper. Moreover, the electric energy quality and the relative influence factors are studied by detailed experiments and analyses. The proposed system is especially suitable for self contained electrical systems, such as those found on electric vehicles, ships, and aircraft, where high performance and compact size are essential.
24 Oct 2005
TL;DR: In this paper, a new control scheme for a regenerative AC/DC/AC converter using model based predictive control is presented, which minimizes quality functions, which represent the desired behavior of the converter.
Abstract: This paper presents a new control scheme for a regenerative AC/DC/AC converter using model based predictive control. The control strategy minimizes quality functions, which represent the desired behavior of the converter. At the inverter side, the load current error is minimized, while at the input side, the active and reactive powers are controlled directly. The main advantages of this method are: no need of linear current controllers, coordinates transformations or modulators for converter and inverter. The rectifier operates with sinusoidal input currents and unity power factor, while sinusoidal currents are generated out at the inverter load.
TL;DR: An active front-end rectifier allows the topology to regenerate and the control strategy handles the reactive input power and reduces the large second current harmonic from the dc-link capacitor, thus reducing its size.
Abstract: Multicell power circuit topologies have proved to be an effective alternative to medium-voltage ac drives. The main advantage is the improved power quality at both the ac system and the motor sides. However, several drawbacks are present in these configurations, such as a lack of sustained regenerative operating mode, uncontrolled input reactive power, and a large second current harmonic that is injected by the load into the dc link of each cell, which leads to a bulky electrolytic capacitor. This paper proposes to replace the input diode-based front-end rectifier with an active front-end rectifier in all cells of the topology and a novel control strategy in order to overcome the aforementioned drawbacks. In fact, the active front-end rectifier allows the topology to regenerate and the control strategy handles the reactive input power and reduces the large second current harmonic from the dc-link capacitor, thus reducing its size. These features are achieved without any penalties in the quality of both the ac input current and the motor voltage waveforms. Experimental results confirm the theoretical considerations.
TL;DR: In this article, the interharmonic generation process is addressed with reference to high power adjustable speed drives based on double stage conversion systems using line commutated or pulse width modulated inverters.
Abstract: The interharmonic generation process is addressed with reference to high power adjustable speed drives based on double stage conversion systems using line commutated or pulse width modulated inverters. Reference is made to ideal supply conditions. Formulas to forecast the interharmonic frequencies due to the interaction between the rectifier and the inverter are developed and a proper symbolism is proposed to recognize the interharmonic origins. Comprehensive analyses are performed for both the considered adjustable speed drives in a wide range of output frequencies and with reference to supply system side, output side, and dc link.
TL;DR: A novel mains voltage proportional input current control concept eliminating the multiplication of the output voltage controller output and the mains ac phase voltages for the derivation of mains phase current reference values of a three-phase/level/switch pulsewidth-modulated (VIENNA) rectifier system is proposed.
Abstract: This paper proposes a novel mains voltage proportional input current control concept eliminating the multiplication of the output voltage controller output and the mains ac phase voltages for the derivation of mains phase current reference values of a three-phase/level/switch pulsewidth-modulated (VIENNA) rectifier system. Furthermore, the concept features low input current ripple amplitude as, e.g., achieved for space-vector modulation, a low amplitude of the third harmonic of the current flowing into the output voltage center point, and a wide range of modulation. The practical realization of the analog control concept as well as experimental results for application with a 5-kW prototype of the pulsewidth-modulated rectifier are presented. Furthermore, a control scheme which relies only on the absolute values of the input phase currents and a modified control scheme which does not require information about the mains phase voltages are presented.
TL;DR: In this article, a current control method based on a sinusoidal internal model is employed, which uses a sine transfer function with a specified resonant frequency, which is called an S compensator.
Abstract: Three-phase voltage-source converters are used as a utility interface. In such a case, the converter line currents are required to track sinusoidal references synchronized with the utility grid without steady-state error. In this paper a current control method based on a sinusoidal internal model is employed. The method uses a sine transfer function with a specified resonant frequency, which is called an S compensator. The combination of a conventional PI compensator and an S compensator is called a PIS compensator. The PIS compensator ensures that the steady-state error in response to any step changes in a reference signal at the resonant frequency and zero hertz reduces to zero. An experiment was carried out using a 1-kVA prototype of three utility interface converters, a voltage-source rectifier, an active power filter, and STATCOM. Almost perfect current tracking performance can be observed. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(3): 54–61, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20064
TL;DR: In this article, a zero-voltage and zero-current-switching (ZVZCS) full-bridge pulse-width modulation converter is proposed, where the auxiliary circuit's capacitance is charged by the center tape of the secondary through a diode, and the capacitor's voltage is clamped through another diode to output capacitor.
Abstract: A novel zero-voltage and zero-current-switching (ZVZCS) full-bridge pulse-width modulation converter is proposed. The ZCS condition of the lagging-leg is obtained by a simple secondary auxiliary circuit resetting the primary current during the freewheeling stage. The auxiliary circuit's capacitor is charged by the center tape of the secondary through a diode, and the capacitor's voltage is clamped through another diode to output capacitor, thus, the voltage stress on the rectifier is clamped. There are neither additional active switches nor resistances in the auxiliary circuit, which makes the proposed converter efficient.