Showing papers on "Power module published in 1991"

Contactless power delivery system for mining applications

Abstract: The ability to transfer large amounts of electrical power (up to 1 MW) to a moving load has traditionally used means that are unreliable, inefficient, and potentially unsafe. These include sliding or rolling metal contacts, sliding carbon brushes, and trailing cables. More recently, flat inductively coupled coils have been used to help mitigate these problems. Except for the inductively coupled coils, these techniques have not been developed with the capabilities of power electronics in mind. This paper presents the first conceptual description of a power delivery system design unifying power electronics and a coaxial-winding transformer for devices that require a contactless connection and/or relative motion while delivering large amounts of power. The transformer's unique characteristics and how they might be used to advantage in combination with power electronics are emphasized. Potential applications are flexible power distribution, material handling, electric vehicle boost, and battery opportunity recharge. Test results of a small scale prototype are presented and verify these initial concepts.

Battery enhanced power generation for mobile X-ray machine

Abstract: A mobile X-ray machine utilizes batteries to provide electrical power to produce high-voltage necessary to generate X-rays during a X-ray exposure. A battery charger circuit is used to supplement the battery during the X-ray exposure and charges the batteries during non-exposure periods. By using batteries to power the X-ray generating device, the X-ray machine is capable of being operated from 110 volt AC power sources permitting the machine to be mobile due to its ability of being operated from ordinary house current.

A.c. power supply apparatus

Abstract: An a.c. power supply apparatus, such as an uninterruptible power supply apparatus or a fuel cell power generation apparatus, has first, second and third converting devices connected in star configuration with a common bus, whereby the number of power converting devices is reduced and a compact, light weight and efficient power supply apparatus is realized.

Semiconductor power module and method of making such a module

Abstract: A power semiconductor module has a plastic envelope and external connection leads. Instead of fixing the connecting leads in the housing by means of a casting compound which cures, as is usual in the prior art, the invention proposes to fix the connecting leads (3, 20) by means of plastic parts (25, 28) which are part of sections formed onto the plastic envelope (2) and are deformed in an ultrasonic welding process while the module is being made.

Power source circuit with a compact size and operating efficiently at low temperature

Abstract: A power source circuit converts direct: current (DC) power into alternating current (AC) power having a required frequency, and provides DC output power according to the AC power. The power source circuit comprises an oscillator for providing a control signal that determines a converting frequency of the AC power; an element provided for the oscillator, having temperature characteristics for increasing the converting frequency at a low temperature; and a device for determining the converting frequency of the AC power according to the control signal provided by the oscillator.

Systeme for protecting and restarting computers and peripherals at remote sites which are accessible by telephone communication

Abstract: An embodiment of the present invention comprises an intelligent power module (IPM) (81-84), a desktop on/off switch, a serial and parallel adapter, and a computer-implemented process on a diskette (90). The intelligent power module (81-84) has an electrical power input and an output to supply power via a user activated manual switch or programmatically using computer instructions to a surge outlet strip or general office equipment (66, 68). It further comprises control circuits (88) which can interpret remote instructions to the IPM to control the flow of AC power to unattended office equipment (66, 68). The IPM (81-84) can be remotely controlled by a user activated manual switch or by the computer (70) itself.

The market for distributed power systems

Abstract: Distributed power architectures replace central power sources with one bulk power supply that is converted to the required voltages by DC/DC power converters at the point of need. The benefits and disadvantages of distributed power systems are summarized. In the last ten years, the design advantages of distributed power systems has spread to a variety of applications, including industrial controls, automotive applications, computer systems, medical electronics, and telecommunications. The market for distributed power architecture is a niche within the switching power supply industry. Approximately two-thirds of respondents among power supply vendors perceive growth in applications for distributed power architectures, although they differ on the rate of acceptance of this technology. Though most of the DC/DC power converters of distributed power architectures are currently used in military/aerospace and communications applications, the real potential for distributed power systems lies within the computer industry. >

Radio-Frequency Transmission Systems: Design and Operation

Abstract: Applications of RF power technology solid state power devices power grid vacuum tubes kylstron vacuum tubes advance power tubes power amplifier support circuitry putting the elements together transmission lines and waveguide RF combiner systems antenna systems reference formulas and tables.

Compact radio-frequency power-generator system

Abstract: An RF power-generator system for the frequency range of 2 to 30 MHz and a programmable sinusoidal power output of 0 to 1000 W. The system is constructed of modules (10, 30, 50, 70 and 90) accommodated in a shallow parallelepipedal housing (1) with a capacity of 4.6 l. The housing essentially comprises two lateral lengths (4) of structural section, a sheet-metal front (6), a sheet-metal bottom (5), and a lid. A crystal-controlled power-oscillator module (10) communicates by way of an RF line (121) with an intermediate module (30). The intermediate-amplifier module communicates by way of still another RF line (122) with a terminal power-amplifier module (50). The terminal power-amplifier module communicates by way of still another RF line (123) with a high-power filter (70). The filter communicates by way of still another RF line (124) with a high-power directional coupler (90). The RF power output can be intercepted at an RF plug (2). A flat fan (120) generates a current of air to cool the power modules (30, 50, 70 and 90). Modules (10, 30, 50 and 90) with built-in electronics all have an integrated control-and-diagnostics unit that communicates by way of multiple cable (125, 126, 127 and 128) with a processor (110). Results are displayed on a display (111). Controls (112) make it possible to employ prescribed operating modes.

Optical power supply for fiber-optic hybrid sensors

Abstract: Systems for optical power supply are of central importance for the concept of fiber-optic hybrid sensors. We present our systems for optical power supply which are capable of giving up to 150 mW of electrical power to the sensor head. Such a system for optical power supply consists of a combination of optical and electronic modules, namely a suitable optical power source, an optical fiber as power link and an optical energy converter with voltage control unit. This concept of a fiber-optic power supply in combination with a fiber-optic hybrid sensor covers many of the advantages given by a pure optical sensor. The galvanic isolation between the measuring circuit and the electronic evaluation unit is notable and implies use at higher voltages with high immunity to interference (EMI) of the data transmission line. A key element for our fiber-optic power supply is a specially developed photo-element array (PEA) for optical–electrical power conversion. Conversion efficiencies of 10–15% ith silicon material and up to 30% with GaAs material have been achieved. The available voltage with our single photoelement array (SPEA) can be up to 8 V. With a multiple photoelement array (MPEA) the voltage is switchable between 8 and 32 V. An application example for a complete fiber-optic hybrid sensor is given. With the fast rate of development of electronic and optoelectronic components, further improvements and a broad range of practical applications can be expected. An outlook to possible future improvements is given.

A high-efficiency 30 W board mounted power supply module

Abstract: A high-efficiency low-profile 30 W power supply module suitable for telecommunications systems, such as the integrated services digital network (ISDN), has been developed This module has an efficiency of 90% and is only 72 mm high A simple MOSFET synchronous rectifier and a low-profile transformer with a flat E core and planar windings were used Its volume is 37 cm/sup 3/ and its power density is 08 W/cm/sup 3/ (13 W/in/sup 3/) It is half the size of a conventional module under natural convection cooling conditions >

Semiconductor power module having an integrated control plate and an error protection plate

Abstract: Known semiconductor power modules having an integrated board for drive and fault protection devices have the board arranged parallel to a base substrate of the module. The invention proposes a vertical arrangement of the board (6), preferably as part of an outside wall of the module, with respect to the baseplate (3), resulting in simpler manufacturing capability and improved cooling.

Comparison of standards limiting harmonic distortion in power systems

Abstract: Harmonic distortion in power systems is growing due to the popularity of switch-mode power electronic equipment. This electronic equipment has recognized advantages, including reducing weight and improving control and efficiency in power converters and supplies. A disadvantage of switch-mode power electronic equipment is that the low-cost utility interface design approach may burden the power system with harmonic loading. Methods to reduce this distortion exist but economic incentives do not. Standards are emerging as the most effective means to influence equipment design and control distortion in power systems. This work compares the major European and American harmonic limiting standards. >

Output power and efficiency tradeoff in full-bridged MOSFET power inverter for use at shortwave frequencies

Abstract: Methods to increase the output power while keeping the power conversion efficiency high are discussed. Examples of the DC-RF MOSFET powers inverter operating at both 2.5 MHz and 3 MHz are presented. Despite the difficulties in designing the full-bridged MOSFET power inverter having the output power enhanced by parallel connection of the MOSFETs operating at shortwave frequencies, the experimental versions were operated with reliability and without any extraordinary temperature rise. >

Considerations about the Design of PV Modules for Central Power Plants

Abstract: PV power systems for utilities require the use of large area solar modules which must be able to operate with high array nominal voltage. The dimensions of the modules can be considerably increased using standard production technology but the necessity to reduce the installation costs force to introduce a new wiring method between modules. Using a suitable disposition of cells interconnection inside the module the electric strength of the component can increase over 10000 V.The paper indicates some rules for the design of large power modules to be used in central power stations by utilities.

Effects of high levels of harmonics from lighting equipment and systems

Abstract: Electronic-controlled gas discharge lighting systems offer efficiency and performance advantages, but to the electric grid they cause nonlinear loads that can cause power quality problems. The author analytically examines the two major concerns: power factor and harmonic distortion. He defines them, demonstrates their independence, and describes their effect on the power lines. It is pointed out that a low power factor results in overcapacity, heavier conductors, and lower efficiency. Problems surrounding harmonic distortion are very similar to those surrounding power factor. Essentially, harmonics contribute to lowering the power factor, resulting in many of the same problems as faced with displacement power factor. >

A 4.0 watt high efficiency 15-18 GHz power MMIC

Abstract: A two-stage Ku-band monolithic power amplifier is reported. The MMIC (monolithic microwave integrated circuit) incorporates a full interstage matching network and a partial input matching network on the chip. The amplifier delivers 4 W of power, 10 to 13 dB of gain, and more than 20% power added efficiency at 2 dB gain compression. This amplifier can be tuned for a 1 GHz instantaneous bandwidth anywhere in the 15-18 GHz band. A 10-W, 20-dB gain power module using five MMICs demonstrates the usefulness of the MMIC as a building block for higher-power amplifiers. >

Radiation-induced effects on special super large n-channel power MOSFETS for space applications

Abstract: Outlines the design, manufacture, and special processing techniques used to attain a solution to radiation-induced effects on super large N-channel power MOSFET dies, sizes 9 and 11, which are approximately 500*690 mils and 772*1022 mils, and still meet the critical and unique requirements of the remote power controller (RPC), the remote bus isolator (RBI), and, above all, the DC-to-DC converter (DDCU) for Space Station Freedom. >

TV-radio converter using a same power supply

Abstract: A TV/radio converter using the common power supply having remocon circuit including main power taking-out device in which applied AC power make main power be applied to the next stage through switching-mode power components and dc-converting components, the device includes; a constant voltage device coupled in the output stage of the switching-mode power components and DC-converting components, wherein the output of the switching mode power components drives the microcomputer (MICOM) and can apply the constant voltage to the next stage, a main power control device, wherein the output of the MICOM controls the input power of horizontal driver components through active components in company with the output of the constant voltage device, thereby controlling the driving power of the TV and radio, and a driving device of a radio, wherein the radio operation can be carried out by driving the switching components using the output of the main power control device and the static voltage device after the active components are driven by the output of the main power control stage. Grading the product up to high-qualified level may be attained.

Electrical system options for space exploration

Abstract: The need for a space power utility concept is discussed and the impact of this concept on the engineering of space power systems is examined. Experiences gained from Space Station Freedom and SEI systems studies are used to discuss the factors that may affect the choice of frequency standards on which to build such a space power utility. Emphasis is given to electrical power control, conditioning, and distribution subsystems.

Switch Mode Power Supply, New Concept

Abstract: A new power supply concept is described. Using the main transformer to transfer the secorrdary regulation signal on a primary winding, a new developed IC controls the primary and secondary voltages to provide more protection in case of disturbance.

Device and process for optimum operation of a power converter connected to a power supply.

Abstract: The invention concerns the avoidance of resonance effects in a power supply of unknown impedance when a power converter connected to the power supply is in operation. In order that, in the case of a locomotive powered by a power converter for instance, standing waves which change uncontrollably as the locomotive travels do not form in the power supply, a characteristic transfer function (e.g. the power-supply input impedance) is first continuously identified by electrical measurement and the use of Fourier transforms and this function simulated at least in the region of the maxima of the function by means of a virtual power supply made up of discrete resonant circuits. The variables of the power-supply model, e.g. the currents flowing in each of the resonant circuits, can be calculated from the identified power-supply parameters as a function of the power-converter switching times. By virtual variation of the switching times, the optimum pulse pattern for power-converter operation can be calculated, this pattern causing no resonance in the true power supply.

Diode laser power module for beamed power transmission

Abstract: Recent progress with powerful, efficient, and coherent monolithic diode master-oscillator/power-amplifier (M-MOPA) systems is promising for the development of a space-based diode laser power station. A conceptual design of a 50-kW diode laser power module was made for space-based power stations capable of beaming coherent power to the moon, Martian rovers, or other satellites. The laser diode power module consists of a solar photovoltaic array or nuclear power source, diode laser arrays (LDAs), a phase controller, beam-steering optics, a thermal management unit, and a radiator. Thermal load management and other relevant aspects of the system (such as power requirements and system mass) are considered. The 50-kW power module described includes the highest available efficiency of LD M-MOPA system to date. However, the overall efficiency of three amplifier stages, including the coupling efficiency, turns out to be 55.5 percent. Though a chain of PA stages generates a high-power coherent beam, there is a penalty due to the coupling loss between stages. The specific power of the 50-kW module using solar power is 6.58 W/kg.

Thermal optimization in a power electronic supply

Abstract: With every-increasing requirements for higher frequency and higher power electronic converters, thermal management considerations and means for thermal analysis have become of great importance. A thermal optimization algorithm of the power devices's positions on the heat sink by means of the NISA II-PC application program is proposed. This algorithm is based on an elaborate thermal and electrical converter model and the three-dimensional finite element method. >

Smart-power devices seek wiser CAE tools

Abstract: The difficulties in developing generalized computer design tools for smart-power semiconductor electronics, a highly specialized field requiring a mix of analog and digital integrated-circuit design, unique semiconductor-device-fabrication technology, and knowledge of application-specific power systems, are examined. These include the problem of dealing with the double-diffused MOS (DMOS) transistor, as well as the simulation of trench refill processes, 2D oxidation phenomena and their stress-induced effects on avalanche breakdown, and the 3D diffusion of the spherical junctions encountered in high-voltage termination. The complexities associated with 2D simulations are discussed in some detail. Dealing with asymmetric devices and with structures consisting of circles, arcs, and 45 degrees angles is also considered. >

The operation of a aluminium-air reserve power systems

Abstract: Alupower-Chloride have developed a practical aluminium-air reserve battery which will provide over 150 Wh/dm/sup 3/ and 250 Wh/kg on discharge. The author describes both the principles and practicalities of operation of the reserve battery and techniques for incorporating them into power systems. The battery is intended to be used in conjunction with conventional, rechargeable, standby batteries and DC/DC power conversion equipment to provide cost-effective short- and long-term regulated power backup to key electrical installations. Two designs of the product are available capable of meeting electrical load requirements from 200 W to 2 kW for periods up to 72 h. >

Low-profile 60 W power pack for telecommunications systems

Abstract: A low-profile 60 W power pack has been developed for use in telecommunications systems under natural convection cooling conditions. This power pack consists of four newly developed 15 W onboard power supply modules (OBPs). An OBP volume of 25 cm/sup 3/ and an efficiency of 86% are achieved using a 500 kHz resonant reset single-ended forward converter with low loss diodes and Ag thick-film paste for high current conducting. To achieve the smallest possible OBP temperature increase, four OBPs are placed in parallel on the lower side of a card. Using these techniques yields a power pack only 9.2 mm wide, i.e., half the conventional width. Thus, this power pack can be assembled within a 15.24 mm pitch in a bookshelf unit. The circuit and physical design technologies used in this low-profile power pack are described, with special emphasis on the OBP circuit design and natural convection cooling design. >