Internal resistance of a tree-based power source

Currently, various types of non-traditional and renewable sources of electrical energy are widely used. If the energy carrier of such sources is free, in the process of operation it is advisable to select the maximum possible power from them, regardless of the fact that the utilization factor of the source's electrical energy in this case may be relatively low. To obtain the maximum amount of electrical energy from the source, two conditions must be met: 1) the source must be brought to the maximum power point (МPP); 2) energy from the source must be taken continuously. As you know, to bring the source into the MPP, it is necessary that the load resistance be equal to the output resistance of the source. Otherwise, the power will be taken from the source, which is less than the maximum possible. Therefore, in cases where the load resistance differs from the output resistance of the source, a matching switching regulator is turned on between the source and the load to match the output resistance of the source with the load resistance. In this case, the input impedance of the switching regulator will be the load of the source. This resistance depends on the load resistance of the regulator, as well as on the relative time of the closed (open) state of the controlled switch S of the regulator t*. Thus, by adjusting the parameter t*, it is possible to ensure the fulfillment of the condition for removing the source into the MPP at various values of the load resistance. In this case, the maximum possible power of the source will be transferred to the load, regardless of the value of its resistance. The dependence of the output parameters of the switching regulator on the parameter t* describe its regulation characteristics. Since, when operating in the maximum power transmission mode, the internal resistance of the source and the load resistance are of the same order of magnitude, when determining the regulating characteristics of the regulator, the internal resistance of the source must be taken into account. The aim of the work is to analyze the control characteristics of the regulator, which operates in the mode of transferring maximum power from the source of electrical energy to the load, as well as to determine the conditions under which it is possible and advisable to operate in this mode. These issues were analyzed using the example of the two most common switching regulator circuits - step-down and step-up regulators. It is shown in the work that, in contrast to the up-type switching regulator, in the down-type regulator, the energy from the power source is taken in discrete portions. Therefore, it can ensure the selection of maximum power from the source only in the t* = 1 mode at a certain value of the load resistance. To ensure continuous extraction of energy from the source, at the input of the switching regulator of the step-down type, it is necessary to install a capacitance of sufficient value. In this case, the circuit can provide maximum power transfer from the source at different load resistances. The paper presents the adjusting characteristics of the analyzed circuits for the case of their operation in the mode of transferring maximum power from the power source to the load, which makes it possible to determine the parameter t* at which the power source is output to the MPP. It is shown that each of the considered circuits can provide the output of the power supply to the MPP only in a certain range of variation of the load resistance of the regulator. For each regulator, an appropriate range of variation of the t* parameter is indicated, depending on whether the power source is a voltage source or a current source.

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Automatic Measurement for Internal Resistance of Battery in Uninterruptible Power Source

Scientific Journal of Riga Technical University Power and Electrical Engineering ◽

10.2478/v10144-009-0030-2 ◽

2009 ◽

Vol 25 (25) ◽

pp. 141-144 ◽

Cited By ~ 1

Author(s):

Mareks Mezitis ◽

Vladimirs Karevs

Keyword(s):

Automatic Measurement ◽

Power Source ◽

Internal Resistance ◽

Differential Method ◽

Power Supplies ◽

Power Sources ◽

Analog Part ◽

Analog Machine ◽

Method Of Measurement ◽

Uninterruptible Power

Automatic Measurement for Internal Resistance of Battery in Uninterruptible Power SourceThis paper considers the approach to the measurement of internal resistance of the battery in the uninterruptible power sources (UPSs [1]). Advantages of the approach are the measurements in power supplies without switching-off the battery, simplicity in realization of algorithm.The basic expressions of the theory used in the method about internal resistance of the storage battery are considered.The function chart of construction of an analog part of the scheme, and also algorithm of action of the scheme of logic of decision-making are considered.Construction of the tracing generator of load, the important part in realization of the method is stated. The use of the analog machine for processing of the results of measurements and a differential method of measurement with the purpose of increase the accuracy of the method is offered.

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Output Characteristics and Circuit Modeling of Wiegand Sensor

Sensors ◽

10.3390/s19132991 ◽

2019 ◽

Vol 19 (13) ◽

pp. 2991 ◽

Cited By ~ 4

Author(s):

Xiaoya Sun ◽

Tsutomu Yamada ◽

Yasushi Takemura

Keyword(s):

Equivalent Circuit ◽

Circuit Simulation ◽

Output Pulse ◽

Power Source ◽

Internal Resistance ◽

Pulse Voltage ◽

Simulink Simulation ◽

Magnetic Wire ◽

Output Characteristics ◽

Significant Attention

A fast magnetization reversal in a twisted FeCoV wire induces a pulse voltage in a pick-up coil wound around a wire. The Wiegand sensor is composed of this magnetic wire and the pick-up coil. As the output pulse voltage does not depend on a changing ratio of the applied magnetic field to switch the magnetization of the wire, the Wiegand sensor is used for to perform rotation and other detections. Recently, the Wiegand sensor has attracted significant attention as a power supply for battery-less operation of electric devices and for energy harvesting. In this study, we propose a concept of obtaining an intrinsic pulse voltage from the Wiegand sensor as its power source, and demonstrate its effectiveness in circuit simulation. The equivalent circuit for the Wiegand sensor is expressed by the intrinsic pulse voltage, internal resistance, and inductance of the pick-up coil. This voltage as a power source and circuit parameters are determined by MATLAB/Simulink simulation. The output voltage calculated using the equivalent circuit of the Wiegand sensor agrees with the experimentally measured results.

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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