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Showing papers on "Flyback converter published in 1995"


Journal ArticleDOI
TL;DR: In this article, the authors introduce the family of quasi-direct converters, i.e., forced-commutated AC/DC/AC power converters including small energy storage devices in the DC link.
Abstract: The paper introduces the family of quasi-direct converters, i.e., forced-commutated AC/DC/AC power converters including small energy storage devices in the DC link. In particular, the case of the three-phase to three-phase quasi-direct power converter is considered. Since energy storage minimization calls for instantaneous input/output power balance, a proper control strategy is needed. The paper describes a simple and effective control technique which also provides high-power factor and small distortion of the supply currents. After a discussion of the general properties of quasi-direct power converters, design criteria of both power and control sections are given, and experimental results of a 2-kVA prototype are reported. >

212 citations


Patent
16 Aug 1995
TL;DR: In this paper, a DC to DC flyback converter topology with one or more transformers and a primary side resonant subcircuit is optimally controlled by providing independently derived duty cycles for driving the main transformer and resonant semiconductor switches to prevent cross-conduction thereof and minimize reverse recovery losses.
Abstract: Resonant DC to DC flyback converter topologies having one or more transformers and a primary side resonant subcircuit are optimally controlled by providing independently derived duty cycles for driving the main transformer and resonant semiconductor switches to prevent cross-conduction thereof and minimize reverse recovery losses.

155 citations


Proceedings ArticleDOI
18 Jun 1995
TL;DR: In this paper, a multilevel voltage-source converter system is proposed for high-voltage, high-power applications such as back-to-back interconnection of power systems, large induction motor drives, and electrical traction drives.
Abstract: In this paper, a multilevel voltage-source converter system is proposed for high-voltage, high-power applications such as back-to-back interconnection of power systems, large induction motor drives, and electrical traction drives. Multilevel voltage-source converters have a voltage unbalance problem in the DC capacitors. The problem may be solved by use of additional voltage regulators or separate DC sources. However, these solutions are found not to be practicable for most applications. The proposed converter system can solve the voltage unbalance problem of the conventional multilevel voltage-source converters, without using any additional voltage balance circuits or separate voltage sources. The mechanism of the voltage unbalance problem is analyzed theoretically in this paper. The voltage unbalance problem of multilevel converters in the DC capacitors has been solved by the proposed internal connections of the AC/DC and DC/AC converters. The validity of the new converter system is demonstrated by simulation and experiment. >

140 citations


Patent
22 Dec 1995
TL;DR: In this paper, a soft-switching DC to DC power converter which minimizes switching losses from a no load condition to a full load condition while operating at fixed frequency is proposed.
Abstract: A soft-switching DC to DC power converter which minimizes switching losses from a no load condition to a full load condition while operating at fixed frequency. Output voltage control is achieved by controlling the phase angle between the two switching networks. High frequency transformer primaries are always excited with a square wave input voltage equal to ##EQU1## The power converter can be implemented with a single transformer. Moreover, the switch voltage never increases the input DC voltage from no load to full load. The power converter can be used in both low voltage high current applications and high voltage low current applications.

120 citations


Proceedings ArticleDOI
05 Mar 1995
TL;DR: In this paper, a buck-boost bi-directional DC-DC power converter topology for electric vehicles with axial-flux PM motor drives is presented. But the experimental results taken from a 20 kW water-cooled prototype of the proposed power converter were evaluated.
Abstract: In brushless DC motor drives devoted to electric vehicles (EVs) a bi-directional DC-DC power converter can be used to control suitably both motoring and regenerative braking operations in order to improve the motor drive performance. In consideration of such an application, this paper deals with the experimental study of a buck-boost bi-directional DC-DC power converter topology which has been conceived for the use in EVs propelled by means of wheel-direct-coupling axial-flux PM motor drives. The paper discusses the power converter modes of operation and reports experimental results taken from a 20 kW water-cooled prototype of the proposed power converter topology. >

106 citations


Patent
21 Apr 1995
TL;DR: In this article, a flyback DC to DC converter is provided comprising a first and a second switching transistors controllable with 180° phase shift and a primary winding of each transformer is coupled in a series circuit with the corresponding switching transistor.
Abstract: Interleaved flyback DC to DC converters are provided comprising a first and a second switching transistors controllable with 180° phase shift and a first and a second flyback transformers. A primary winding of each transformer is coupled in a series circuit with the corresponding switching transistor. A secondary winding of the first transformer is coupled with the secondary winding of the second transformer via a first catch diode and both said secondary windings are coupled to an output filter capacitor via a second and a third catch diode, correspondingly. When discharging to the output filter capacitor, the transformers interlock each other. By interlocking, non-pulsating output current is generated and voltage across switching transistors is reduced. A secondary quasi-resonant snubber network relieves voltage spikes across the switching transistors. A common magnetic core of the transformers cuts the cost and the size of the interleaved flyback converters.

92 citations


Patent
24 Feb 1995
TL;DR: In this article, a high efficiency high power DC to DC power converter and controller system for a CD ignition system with a simple converter controller (8) for controlling a power switch (2) of a transformer (1) operated as a flyback which includes a lossless snubber (6) and simple current sensor (8a) for sensing and controlling the power converter current, and further including ignition trigger conditioner (9) and phase conditioner(10) for operating a trigger output circuit (11) based on an octal counter (67) for triggering ignition coil circuits
Abstract: A high efficiency high power DC to DC power converter and controller system for a CD ignition system with a simple converter controller (8) for controlling a power switch (2) of a transformer (1) operated as a flyback which includes a lossless snubber (6) and simple current sensor (8a) for sensing and controlling the power converter current, and further including ignition trigger conditioner (9) and phase conditioner (10) for operating a trigger output circuit (11) based on an octal counter (67) for triggering ignition coil circuits of a preferred distributorless ignition circuit of the hybrid ignition system type.

89 citations


Proceedings ArticleDOI
18 Jun 1995
TL;DR: In this paper, the half-bridge complementary control power converter has been proposed as a low-output voltage DC-to-DC power converter due to its excellent features (efficiency around 90% at as low an output voltage as 33 volts) and a study of the statics and dynamics of this power converter is proposed.
Abstract: The half-bridge complementary-control power converter has been recently proposed as a low-output voltage DC-to-DC power converter due to its excellent features (efficiency around 90% at as low an output voltage as 33 volts) A study of the statics and dynamics of this power converter is proposed in this paper Thus, DC voltage conversion ratio both in continuous and discontinuous conduction mode, the boundary between both modes, the DC current level in the transformer and a small-signal average model have all been obtained From the latter, transfer functions between duty cycle and output voltage and between input and output voltages have been also obtained, and some simplifications and design rules have been proposed to facilitate the design of the feedback loop >

78 citations


Patent
03 Feb 1995
TL;DR: In this article, a PWM-controlled flyback converter with a single transformer and a primary side resonant subcircuit is proposed to minimize reverse recovery losses, where the primary windings are connected in series, the first transformer having substantially greater inductance than the second transformer.
Abstract: Resonant DC to DC power converter topologies include a PWM-controlled flyback converter having a single transformer and a primary side resonant subcircuit that is optimally controlled to minimize reverse recovery losses. A second transformer may be added wherein the primary windings are connected in series, the first transformer having substantially greater inductance than the second transformer to more efficiently transfer energy over a wide range of output load conditions. A combined forward-flyback resonant converter utilizing a load-side buck loop for increased power delivery performance and start-up circuitry for initial power connection of the converter to a voltage source utilizing a hysteresis protection circuit are also disclosed.

75 citations


Patent
Walter Zeitler1, Ernst Gabriel1
18 Aug 1995
TL;DR: In this article, the authors present a control circuit for fluorescent lamps, which includes a pulse width modulator, a multivibrator and a start/stop controller, which varies the duty cycle of a control signal supplied to the DC-to-DC converter based on a feedback signal from the DC to DC converter and halts the operation of the power output stage if a failure is detected.
Abstract: A device for operating lamps, such as fluorescent lamps includes an input protection circuit, a filter, a DC to DC converter, a power output stage, a lamp connecting circuit and a control circuit. The control circuit includes a pulse width modulator, a multivibrator and a start/stop controller. The pulse width modulator varies the duty cycle of a control signal supplied to the DC to DC converter based on a feedback signal from the DC to DC converter. The multivibrator assists in the control of the DC to DC converter. The start/stop controller initiates the operation of the power output stage when an output of the DC to DC converter reaches a predetermined level and halts the operation of the power output stage if a failure is detected.

73 citations


Journal ArticleDOI
TL;DR: In this paper, the state variables of the LC filter connected to the AC side of the converter are fed back to the PWM pattern generator, thereby eliminating a DC offset of the AC input currents as well as oscillations of the DC output current during transients.
Abstract: This paper presents a new state feedback based control strategy for a PWM AC to DC voltage type converter with phase and amplitude control. In this control strategy the state variables of the LC filter connected to the AC side of the converter are fed back to the PWM pattern generator, thereby eliminating a DC offset of the AC input currents as well as oscillations of the DC output current during transients. Computer simulation of the converter system with the proposed control strategy shows that the transient waveforms of AC input and DC output currents are improved greatly even if the damping effect of the AC side resistance can not be expected. The DC voltage regulation with good dynamic response is also achieved even if DC capacitance is substantially reduced. Experimental results from a low power laboratory model are also included to confirm the simulated results and to demonstrate the effectiveness of the proposed control strategy. >

Journal ArticleDOI
TL;DR: A physically-based power MOSFET model with continuous and accurate curves for all three interelectrode capacitances is presented in this article, which is used to design a snubber for a flyback converter.
Abstract: A fundamentally new, physically-based power MOSFET model features continuous and accurate curves for all three interelectrode capacitances. The model equations are derived from the charge stored on two internal nodes and the three external terminals. A straightforward parameter extraction technique uses the standard gate-charge plot or process data and is matched with interelectrode capacitance measurements. Simulations are in excellent agreement with measurements. The model is used to design a snubber for a flyback converter. >

Patent
19 Sep 1995
TL;DR: In this article, a transient over-voltage protection circuit is proposed to protect the DC to DC converter from input voltages that exceed the converter's operational limits by partially opening a switch connected between a rectifier circuit and a DC-to-DC converter.
Abstract: A transient over-voltage protection circuit includes a normally closed switch connected between a rectifier circuit and a DC to DC converter. This switch is caused to partially open when the voltage input to the DC to DC converter exceeds a predetermined value, thereby protecting the DC to DC converter from input voltages that exceed the converter's operational limits. The switch is returned to its normally closed state when the level of voltage input to the converter drops below a predetermined lower value. A capacitor connected across the input terminals of the converter is charged up when the switch is closed and functions to supply power to the DC to DC converter when the switch is in its partially opened or current limit state.

Proceedings ArticleDOI
05 Mar 1995
TL;DR: In this paper, a three-switch HV converter derived from the Cuk converter is presented, which offers simpler structure and control, higher efficiency, reduced EMI, size and weight savings than traditional switched-mode regulated voltage multipliers.
Abstract: A novel three-switch HV converter derived from the Cuk converter is presented. This converter can operate into a capacitor-diode voltage multiplier, which offers simpler structure and control, higher efficiency, reduced EMI, size and weight savings than traditional switched-mode regulated voltage multipliers. Two significant advantages are the continuous input current and easy isolation extension. The new converter is experimentally verified. Both the steady state and dynamic theoretical models are correlated well with the experimental data. >

Patent
Kyung-Sang Lee1
14 Jul 1995
TL;DR: In this paper, a power-supply controller of a computer can minimize power-consumption as shown in the following description, which is composed of a power supply, a power controller, and a powermode controller.
Abstract: The power-supply controller of a computer can minimize power-consumption as shown in the following description. The operation mode will convert to a sleep-mode reducing the power-consumption below a constant voltage if there is no input to operate a computer system for a predetermined period of time. If the condition of no input for operating a computer system persists, the power supply controller cuts off the power-supply once again. In order to achieve this object, this invention is composed of a power-supply, a power-controller, and a power-mode-controller. The power-supply includes a first rectifier that converts an AC voltage to a DC voltage, a DC/AC converter which converts a DC voltage into an AC voltage, a switching mechanism which outputs a pulse signal used to operate the DC/AC converter, a second rectifier which converts to a DC voltage from an AC voltage received from the DC/AC converter, and a driver which provides an operation voltage to operate the switching mechanism. The power-controller outputs a power-supply signal used to change from the sleep-mode into a power-off mode if there is no input for a predetermined period during the sleep-mode, and which outputs a power-supply signal to change from the power-off mode into a resume-mode if there is an input. The power-mode-controller also includes a power-mode control circuit that varies the output from the power-controller and varies an operation voltage to operate the switching mechanism and a charger which charges a battery with AC voltage and provides the power-controller with a power-supply.

Proceedings ArticleDOI
05 Mar 1995
TL;DR: In this article, a small-signal model of soft-switched asymmetrical half-bridge DC/DC converter operating in a continuous inductor conduction mode is proposed.
Abstract: A small-signal model of soft-switched asymmetrical half-bridge DC/DC converter operating in a continuous inductor conduction mode is proposed. The analysis of this model is applicable to converters with any type of output rectifier (full-wave or half-wave). Based on the proposed model, the feedback compensation network for a prototype converter was designed. An open loop frequency response and voltage ripple attenuation of the converter with closed feedback loop were calculated. The experimental results validated all theoretical predictions. >

Patent
Ogawa Yoshio1
15 May 1995
TL;DR: In this paper, a control apparatus for controlling a motor of an air conditioner includes a converter (2), having switching means (2a) for improving an input power factor, for converting an AC power to a DC power and an inverter (4) for converting the DC power supplied from the converter to the AC power and supplying to a compressor.
Abstract: A control apparatus for controlling a motor of an air conditioner includes a converter (2), having switching means (2a) for improving an input power factor, for converting an AC power to a DC power and an inverter (4) for converting the DC power supplied from the converter to the AC power and supplying to a compressor (3). The output DC voltage of the converter is detected by a DC voltage detecting circuit. An input alternating current is detected by a current detecting circuit (11). A microcomputer (13) for controlling the inverter calculates a current command from data stored on the basis of the detected voltage. The detected current is compared with the current command, an ON percentage of a PWM signal to control the switching means is obtained, and the PWM signal is generated.

Proceedings ArticleDOI
05 Mar 1995
TL;DR: In this article, a general-purpose fuzzy controller for DC-DC converters is investigated, based on a qualitative description of the system to be controlled, and fuzzy controllers are capable of good performances even for those systems where linear control techniques fail, e.g. when a mathematical description is not available or in the presence of wide parameter variations.
Abstract: In this paper, a general-purpose fuzzy controller for DC-DC converters is investigated. Based on a qualitative description of the system to be controlled, fuzzy controllers are capable of good performances even for those systems where linear control techniques fail, e.g. when a mathematical description is not available or in the presence of wide parameter variations. The presented approach is general and can be applied to any DC-DC converter topologies. Controller implementation is relatively simple and can guarantee a small-signal response as fast and stable as for other standard regulators and an improved large-signal response. Simulation results of buck-boost and Sepic converters show control potentialities. >

Journal ArticleDOI
TL;DR: A coal mine power system and a DC electrified transit railway system with regenerative braking function, a part of Taipei Rapid Transit Systems under planning, have been analyzed to show the improved accuracy and good convergence characteristics of the developed Newton-Raphson power flow formulation with the proposed converter model.
Abstract: Because of lower voltage levels and smaller power ratings, the R/X ratio of commutation impedance in industrial AC/DC distribution systems is usually higher than that in HVDC transmission systems. Considerable discrepancies may therefore occur in industrial AC/DC power flow results, especially the reactive power consumption of converters, if the commutation resistances of the converters are neglected. To describe the effects of commutation impedance on converter operations and to precisely relate the fundamental line current and DC output current of the converter, a detailed model of the bridge converter with commutation impedance for use of Newton-Raphson power flow studies in industrial AC/DC power systems is derived in this paper. A coal mine power system and a DC electrified transit railway system with regenerative braking function, a part of Taipei Rapid Transit Systems under planning, have been analyzed to show the improved accuracy and good convergence characteristics of the developed Newton-Raphson power flow formulation with the proposed converter model. >

Journal ArticleDOI
08 Oct 1995
TL;DR: In this paper, a three-phase DC-to-DC series-parallel resonant converter is proposed and its operating modes for a 180/spl deg/ wide gating pulse scheme are explained.
Abstract: A three-phase DC-to-DC series-parallel resonant converter is proposed and its operating modes for a 180/spl deg/ wide gating pulse scheme are explained. A detailed analysis of the converter using a constant current model and the Fourier series approach is presented. Based on the analysis, design curves are obtained and a design example of a 1-kW converter is given. SPICE simulation results for the designed converter and experimental results for a 500-W converter are presented to verify the performance of the proposed converter for varying load conditions. The converter operates in lagging power factor (PF) mode for the entire load range and requires a narrow variation in switching frequency, to adequately regulate the output power.

Journal ArticleDOI
TL;DR: This paper introduces, analyzes, and experimentally verifies a novel DC/DC converter called the current-source parallel-resonant converter, which consists of a large choke inductor, two switches, and a parallel- Resonant circuit.
Abstract: This paper introduces, analyzes, and experimentally verifies a novel DC/DC converter called the current-source parallel-resonant converter. The converter consists of a large choke inductor, two switches, and a parallel-resonant circuit. Each switch consists of a MOSFET in series with a diode. It has a nonpulsating input current with a very low AC ripple. The MOSFETs are driven with respect to ground and, therefore, have a simple gate-drive circuit. The analysis of the converter is carried out in the frequency domain using Fourier series techniques. Analytical expressions are derived for performance parameters of the converter. A prototype of the converter circuit was designed, built, and tested. The theoretical results were in good agreement with the experimental results. >

Patent
21 Apr 1995
TL;DR: In this paper, a control circuit for an inductive load, such as a phase winding of a reluctance motor, includes a boost flyback converter and a suppressor switch for controlling the application of rectified current to the dc link capacitor.
Abstract: A control circuit for an inductive load, such as a phase winding of a reluctance motor, includes a boost flyback converter. The controller includes a dc link capacitor switchable across the load by means of a control switch and a suppressor switch for controlling the application of rectified current to the dc link capacitor. The suppressor switch is operated independently of the control switch in order to control the rectified current so that it follows the sinusoidal input voltage waveform. By this technique, the harmonics generated by switching the rectified input current are substantially suppressed.

Patent
13 Feb 1995
TL;DR: In this paper, a continuous mode full wave power converter topology which integrates the buck-boost (flyback) and buck converter properties is presented. But the voltage transfer function is not characterized.
Abstract: A continuous mode full wave power converter topology which integrates the buck-boost (flyback) and buck converter properties. The voltage transfer function is M = (D/(1-D)), characteristic of the buck-boost (flyback) converter. Characteristic of the full wave buck converter, the inductor current is source continuous during the alternate D intervals, source discontinuous during the simultaneous (1-D) intervals, and load continuous during both the D and (1-D) intervals. A continuous mode full wave power converter topology which integrates the buck-boost (flyback) and buck converter properties. The voltage transfer function is Eout = Ein (D/(1-D)), characteristic of the buck-boost (flyback) converter. Characteristic of the buck converter, the inductor current is source continuous during the alternate D intervals, source discontinuous during the simultaneous (1-D) intervals, and load continuous during both the D and (1-D) intervals.

Patent
05 Jun 1995
TL;DR: In this article, a flyback charger for an energy-storage capacitor has a controller for causing the energy storage pulses of current in the transformer primary winding and the energy delivery pulses in the secondary winding to be nearly flat-topped.
Abstract: A flyback charger for an energy-storage capacitor has a controller for causing the energy-storage pulses of current in the transformer primary winding and the energy-delivery pulses of current in the transformer secondary winding to be nearly flat-topped. The controller includes a peak-current-commanding current-mode control or a valley-current-commanding current-mode control which controls the duration of a switching circuit on and off interval, respectively, responsive to the current flowing in the transformer primary winding and secondary winding, respectively. A feed-forward controller controls the duration of the switching circuit off and on interval, respectively, in response to the voltage provided by the secondary winding and D-C supply voltage, respectively. When using the valley-current-commanding current-mode controller, there may be a fixed duration of the switching circuit on interval.

Patent
27 Apr 1995
TL;DR: In this paper, an analog-to-digital converter calibration method for a charge redistribution analog to digital converter is presented, that includes adjusting an input offset of an input of the analog to the digital converter and adjusting a gain offset of the ADC.
Abstract: A charge redistribution analog-to-digital converter. This converter includes an offset correcting circuit operatively connected in parallel with a capacitor array and responsive to a sampling input of the analog-to-digital converter, and a gain correcting circuit operatively connected in parallel with a sampling capacitor and responsive to the sampling input of the analog-to-digital converter. In another general aspect, an analog-to-digital converter calibration method for a charge redistribution analog-to-digital converter, that includes adjusting an input offset of an input of the analog-to-digital converter and adjusting a gain offset of the analog-to-digital converter. The steps of adjusting are then repeated until a predetermined level of error is achieved for the analog-to-digital converter.

Patent
09 Nov 1995
TL;DR: In this article, a bi-directional converter for transferring electrical energy between a high voltage AC power grid and a DC energy storage/supply (such as a battery or a series of photovoltaic or fuel cells) is presented.
Abstract: A bi-directional converter (i.e., AC- > DC or DC- > AC) for transferring electrical energy between a high voltage AC power grid (12) and a DC energy storage/supply (22) (such as a battery or a series of photovoltaic or fuel cells). The converter includes a PWM inverter (20) coupled to the grid (12), and a DC-DC chopper (21) coupled between the PWM inverter (20) and a DC energy storage/supply (22). The PWM inverter (20) includes a switching circuit (26) having high speed electrical switches arranged in pairs coupled between the AC grid phase voltage rails and DC-DC chopper voltage rails. An inverter control unit (24) includes a DC bus voltage regulator (40) to regulate the voltage on the DC side of the PWM inverter (20), and a reactive power controller (42). A DC control unit (23) includes a real power controller (41) that controls the real power flow by controlling the current flow of the DC energy storage/supply (22). By modulating the DC switches (25) in the DC-DC chopper (21), the DC current to the DC energy storage/supply (22) is controlled to provide a desired real power flow through the DC-DC chopper (21), independent of the voltage (VDC) of the energy storage/supply (22).

Patent
30 Oct 1995
TL;DR: In this article, a multi-channel single-stage high power factor AC to DC converter comprising a pair of input terminals for connecting to an a.c. supply voltage, a bridge rectifier connected across the input terminal, and a D.C. output voltage thereacross.
Abstract: A multi-channel single stage high power factor AC to DC converter comprising a pair of input terminals for connecting to an a.c. supply voltage, a bridge rectifier connected across the input terminal, for converting the a.c. supply voltage to a d.c. voltage, and a D.C. to D.C. converter connected to the bridge rectifier and including a high frequency switch for converting the d.c. voltage to high frequency intermittent pulses, a transformer having a primary winding connected to the high frequency switch and having at least two secondary windings each connected to a respective rectifier for producing a d.c. output voltage thereacross. A pair of capacitors are connected in the input of the DC to DC converter so that when the switch is OPEN a first one of the capacitors receives energy from the a.c. supply and a second one of the capacitors receives energy from the transformer, whilst when the switch is CLOSED the first capacitor restores energy to the transformer and the second capacitor restores charge to the a.c. supply. Such a configuration avoids the need to split the energy transfer capacitor between the input and output of the DC to DC converter and thus avoids duplication of part of the energy transfer capacitor in each output channel when multiple outputs are provided.

Journal ArticleDOI
18 Jun 1995
TL;DR: In this article, the use of several zero-current-switched (ZCS) quasi-resonant converters (QRCs) with a half-wave switch, working as power factor preregulators with voltage-follower control, was investigated.
Abstract: In this paper, we propose to study the use of several zero-current-switched (ZCS) quasi-resonant converters (QRCs) (buck-boost, flyback, SEPIC, Cuk, boost, and buck) with a half-wave switch, working as power factor preregulators (PFPs) with voltage-follower control. The analysis carried out demonstrates that these converters show excellent characteristics to obtain a high power factor (PF) without using any input-current feedback loop, and they also allow high switching frequency to operate because they integrate transformer and rectifier diode parasitics into the power topology.

Journal ArticleDOI
TL;DR: How the necessity of using a Tri-Level PWM strategy in the current source inverter can be turned into an advantage by producing a voltage boost so that transformers are no longer required is described.
Abstract: The peak line-to-line inverter AC voltage, in general, cannot exceed the supply DC voltage and transformers have to be used when voltage step-up is required. This paper describes how the necessity of using a Tri-Level PWM strategy in the current source inverter can be turned into an advantage by producing a voltage boost so that transformers are no longer required. During the frequent occurrence of the "shoot-through" states, which is the characteristic of the Tri-Level PWM-controlled inverter, magnetic energy builds up in the DC link inductor. At the end of these periods, the L/sub dc/dI/sub dc//dt voltage across the inductor augments the inverter output voltage in the same way as in the basic boost type DC/DC power converter. The paper describes the circuitry required to ensure linear control. Analytical, simulation, and experimental results are given. Applications are found in all instances where the AC voltage is higher than the available supply DC voltage. >

Journal ArticleDOI
TL;DR: In this article, a frequency domain analysis is applied to a controlled HVDC power converter interconnecting AC and DC power networks, and the converter is considered as a three-port network, and described using transfer functions.
Abstract: A frequency domain analysis is applied to a controlled HVDC power converter interconnecting AC and DC power networks. The converter is considered as a three-port network, and described using transfer functions. Using AC and DC power system frequency dependent impedances, an equivalent electrical circuit is constructed. The concept of composite resonance is introduced to emphasise the interaction between the AC and DC systems, and a simplified damping factor derived to predict the dynamics of waveform distortion during transient recovery. The frequency domain analysis is verified by dynamic simulation. >