Showing papers on "Buck converter published in 1980"

Continuous power source with bi-directional converter

Abstract: A power source provides continuous AC power by employing a bi-directional converter (10) which interfaces a rechargable DC power storage device (30) with AC mains power and AC loads. The bi-directional converter (10) includes a transformer (75) having first and second windings (72, 74) coupled in reverse polarity through dual switching means (52, 54) in parallel with one another. The switching means (52, 54) are coupled to a state controller (20) responsive to conditions at the AC mains terminal, the AC load terminal and the DC power terminal. There are two general operating conditions, an active condition wherein DC power is provided to the AC load, and a standby condition wherein power is recovered by the DC storage device (30). In the standby condition, the converter (10) operates in a so-called flyback mode to recover power and to direct it to the DC storage device (30). In the active condition, the converter (10) is pulse-width modulated according to a predetermined duty cycle to produce an AC sine wave output at the AC load terminals. Where the AC load includes reactive components, the converter (10) operates to recover unused power from the load and to transfer power back to the DC power source (30) whenever the polarity of the output voltage differs from the polarity of the output current.

Solid state regulated power transformer with waveform conditioning capability

Abstract: Apparatus for providing the voltage transformation functions of a conventional electrical power transformer. An AC input signal is chopped in a solid state switching converter at a frequency very much larger than the frequency of the input signal and then filtered to attenuate the high frequency component while passing the frequency of the AC input signal. The switching converter includes a pair of bidirectional solid state switches, an inductor and a capacitor connected in a buck converter, boost converter or buck-boost converter arrangement to provide a step up, step down, or step up/step down capability, respectively. A feedback signal modulates the duty cycle of the switching converter to provide automatic voltage regulation under varying loads and leading and lagging power factors.

Control device for the maximum power output of a photovoltaic converter

Abstract: The converter supplies an application circuit (8) and the device is characterised in that it comprises control means (12, 13 ... 18, 20) connected between output terminals (9, 10) of the converter and the application circuit (8), to obtain the derivative of the power P delivered by the converter, with respect to the voltage V at its terminals, and to minimise the value of this derivative. Application to the expedient utilisation of photovoltaic power.

Pulse burst regulated d.c. power supply apparatus and method

Abstract: A power supply which serves as a power converter from a relatively low primary direct current energy source, to a generally higher value of secondary direct current power for application to an electric load element. The secondary power is voltage regulated. Regulation is provided by limiting the number of electric pulses of primary power produced by the converter to not more than the least total number of such pulses necessary to maintain the secondary voltage at its preferred average d.c. voltage level.

An Adaptive-Control Switching Buck Regulator-Implementation, Analysis, and Design

Abstract: Describing-function techniques and averaging methods have been employed to characterize a multiloop switching buck regulator by three functionsl blocks: power stage, analog signal processor, and pulse modulator. The model is employed. to explore possible forms of pole-zero cancellation and the adaptive nature of the control to filter parameter changes. Analysis-based design guide lines are provided including a suggested additional RC-compensation loop to optimize regulator performances such as stability, audiosusceptibility, output impedance, and load transient response.

Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1

Abstract: The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.

Bias Voltage Controlled Three-Phase Converter with High Power Factor

Abstract: In rectifier systems, the compensation of reactive power accompanied with conventional line commutation is a significant problem. The most desirable and effective technique for realizing reactive power compensation is not the addition of more reactive compensators but the improvement of the converter circuit in itself. The new three-phase converter using the latter technique is proposed and discussed. It consists of a combination of the bias voltage control and the conventional phase control. The original scheme of this was presented in [1] for the single-phase type. The new three-phase converter scheme, its operation, characteristics such as power factor, harmonic contents of line current, design indexes, and experimental results are described. The new converter proposed will be suitable for large power systems.

Method and apparatus for enhancing the output of an RMS converter

Abstract: A method and apparatus for enhancing the output of a log-antilog type root-mean-square (RMS) converter by correcting the RMS converter output for nonlinearities in the AC/DC transfer characteristic of the converter are disclosed. First, preselected positive and negative DC voltages near the upper and lower ends of the range of the RMS converter are applied to the RMS converter and the output of the converter is measured by a voltage measuring instrument for each applied voltage. The applied and measured voltage values are used to determine the positive and negative gain (G) and offset voltage (V 0 ) characteristics of the RMS converter. The characteristic information is used to correct (e.g., enhance) the output of the RMS converter when AC voltages falling within the range of the converter are later applied. The same procedure is followed for each range of the RMS converter, if the RMS converter has multiple ranges. Further enhancement is provided by correcting for gain errors resulting from crest factor variations. Crest factor variation enhancement is provided by applying preselected square waves to the converter and measuring the output of the converter. The measured output voltages are utilized to determine the positive and negative gain crest factor correction constants, which are used to correct the positive and negative gain characteristics of the RMS converter.