Showing papers on "Power optimizer published in 1980"

Multiple wind turbine tethered airfoil wind energy conversion system

Abstract: A generally toric lighter-than-air gas bag-type airfoil (12) is tethered by tethers (14) to the ground at a plurality of angularly widely distributed points at whinches (21) about the periphery of the gas bag. A wind turbine (WT) is mounted at the entrance to the axially central vent (16). The tether lines are entrained about individually operable power winches (21), preferably controlled by a micro-processor (TCS) which takes in wind direction and tether line tension data and operates the winches (21) and inflation gas inlet and outlet valves (40, 28) to orient the wind turbine into the wind for maximum power output. In other embodiments, a plurality of wind turbines (WT) are supported aloft on the same tethered airfoil (112) which is provided with apparatus (124, 130, 132, 134, 126, 140, TCS) for orienting the wind turbines (WT) into the wind. Various ways and devices, see Fig. 2, are described for converting the wind energy into electrical power and for connecting and providing the plural outputs to the same electrical power grid. The principles are applicable whether there are a small number of relatively large wind turbines, a large number of relatively small wind turbines or some of each.

Solar power system requiring no active control device

Abstract: A solar power system has a photovoltaic array having a locus of peak power points for various insolation levels, a voltage-dependent variable resistance load such as a water electrolysis unit electrically connected to the array, and a demand-dependent variable resistance load such as a DC to AC inverter connected in parallel with the electrolysis unit. The electrolysis unit or other voltage-dependent variable resistance load has a voltage-current characteristic in which the operating point is displaced from the array's peak power point for most insolation levels. The characteristic is displaced towards higher voltage-lower current operating points. The inverter may move the operating point of the photovoltaic array toward its peak power point when the load requires power. The system may be designed so that the array operates within about 5 percent of its peak power point over a wide range of inverter power demands. A fuel cell may be connected in parallel with the array to provide power to the inverter at low insolation levels, at night or in low sunlight. The fuel cell may use the hydrogen produced by the electrolysis unit for fuel. The total photovoltaic power made available by the system of this invention is generally greater than 95 percent and often greater than 98 percent of the maximum power which the photovoltaic array may produce for many insolation levels.

A New, Fast Technique for Load-Flow Solution of Integrated Multi-Terminal DC/AC Systems

Abstract: The paper describes a new technique for the load-flow calculations of integrated ac/dc systems. The technique is fast, efficient and reliable and is therefore an improvement over known procedures. The representation of dc system is such that it leads to simplifications in calculations and saving in storage requirement and yet it is so ; eneral that a multi-terminal dc system of anyconfiguration and control characteristics can be easily simulated. The procedure uses fast decoupled load flow method, handles all ac/ dc equations simultaneously, and fully exploits the sparsity techniques. The paper shows application of the technique on two systems, one with a point-to-point dc transmission and the other with a 3-terminal mesh HVDC sub-system.

Aircraft wind energy device

Abstract: A tornado-type wind energy system is provided which is suitable for aircraft in flight or emergency use. Wind energy propels a turbine to provide shaft power to drive an electrical generator or the like. A vortex flow regime is produced downstream of the ram air driven turbine. The creation of a low pressure core draws ram air by the turbine at an increased rate, thereby generating greater shaft power to a load.

High input voltage DC to DC power converter

Abstract: A modular arrangement of DC to DC Power conversion units which permits variation of power handling capability without changing the power control system. The conversion units of the stagger-mode type including two pulse width modulated converter sub-units are separated into two individually powered and controlled units. First units of all converters are connected in one series string across a power source and similarly the second units of all converters are connected in a second series string across the power source. Each unit has a capacitor connected across its power input terminals so that the source voltage is evenly divided between converters. With this configuration only one converter need have its current monitored in order to balance the current between the two strings of converter units. The system includes current and voltage protection features appropriate to a high current and high voltage environment.

Wind turbine for marine propulsion

Abstract: A wind turbine on an essentially vertical mast converting wind power to electric power for the propulsion motors of a screw propelled ship. The turbine is omnidirectional and capable of being reefed for speed control.

Wind energy conversion system with reaction torque for power control

Abstract: A wind energy conversion system for converting wind energy into controlled wind turbine torque comprising a wind turbine with an essentially horizontally disposed shaft, a means, rotatably mounted to a chassis, for sensing and reacting to wind turbine torque such that reaction torque acting on the means causes angular displacement of the means, a driven machine drivenly connected to the shaft of the wind turbine, and a means for adjusting wind turbine efficiency which is drivenly connected to the first mentioned means in such a way as to prevent continual angular speed thereof. Angular displacement of the first mentioned means provides the power for the last mentioned means to adjust wind turbine efficiency. Because the system can be designed so as to provide a substantially constant torque to the driven machine over a significant range of wind speeds, the system is particularly useful for generating electrical power suitable for transfer to an alternating current power network of an electrical utility company.

Transductor-regulators for switched-mode power supplies

Abstract: In switched-mode power supplies the problem of stabilizing two or more output voltages often arises. Since with pulse-width modulation of the switching power transistors only one output can be exactly regulated it is necessary to restabilize the other outputs with additional regulators. For this particular case, transductors have been developed with an efficiency of over 90 % at operating frequencies between 20 kHz and 50 kHz. They can be used in push-pull and forward converters.

Performance evaluation of wind turbines

Abstract: A relatively straightforward technique termed the method of bins has been developed that may be used in the determination of the average output characteristics of a particular wind turbine. The technique is applicable to any size or type wind turbine. The output power of a wind turbine as a function of wind speed is not an adequate measure of the power production of a wind turbine. However, the output power as a function of wind speed can be combined with either a knowledge or an estimate of the wind characteristics at a particular location to predict the annual power produced by the turbine. This approach of estimating the annual power production of a wind turbine in some assumed environment is a useful way of evaluating different machines or of evaluating the effects of locating a particular machine at different sites.

Wind powered generator

Abstract: A wind driven device capable of generating electrical power or performing other useful work by transforming wind energy into a rotational power source.