| section Home
Production, Amateur Radio amateur Model aircraft, rocket- Useful, entertaining |
Stealth master
Electronics Physics Technologies invention |
space Mystery
Earth Mysteries Secrets of the Ocean Stealth section Map |
  |
| Use of material is permitted for reference (for websites - hyperlinks) | |||
Navigation: => |
Home / Products Patents / In the section of the catalog / back / |
|
INVENTION
Russian Federation Patent RU2046490
DEVICE IMPROVING THE QUALITY OF POWER In three wire ELECTRIC NETWORKS
Name of the inventor: Tanks Y.
The name of the patentee: Ivanovo State Power Engineering University named after VI Lenin
Address for correspondence:
Starting date of the patent: 1993.06.08
Use: to improve the quality of power supply through the use of multi-function devices, performing tasks limit short-circuit currents, compensating harmonics and reactive power, voltage regulation and balancing the load current and voltage. The inventive current-limiting device and the source of the reactive power formed on the basis of controlled reactors and capacitor batteries are controlled by the programmable controller, wherein controlled thyristor source reactive power valves connected in star and are connected to the phases of the electrical network through a reactor control winding in series with which includes capacitor banks connected to the phases of the uncontrolled rectifier, loaded on the winding of the reactor and the bias resistor.
DESCRIPTION OF THE INVENTION
The invention relates to electrical engineering and is intended to improve the quality of power supply of industrial plants in the three-wire power networks, which refers to improving the quality of electricity from power consumers and the reliability of their work by limiting the short-circuit current, reactive power compensation, voltage regulation, compensation of harmonics, load balancing currents and voltage balancing.
Known devices combined balancing and voltage three-phase current networks having up to six power elements having longitudinal and transverse inclusion.
Their main disadvantage is low efficiency and the inability to use the same time to limit the short-circuit current, harmonic compensation, reactive power compensation and voltage regulation. There is no possibility of smooth regulation of power quality.
A device for controlling the three-phase ac reactive power, comprising a three phase capacitor bank, each phase of which consists of two series-connected sections, by the number of chains of serially connected phase reactors and two anti-parallel connected thyristors. The device can simultaneously be used for reactive power compensation and balancing mode power supply.
Disadvantages of the device are the lack of limits short-circuit currents in low filtration properties and increased generation of higher harmonics.
The closest to the invention in the technical essence and achieved result is a device which comprises a thyristor reactive power source, formed as a thyristor bridge, in one diagonal of which two control windings included controlled reactor, and in the other diagonal is included a resistor, with the main winding controlled reactor introduced sequentially into the electricity network.
Disadvantages of the device: a small range of reactive power regulation and increased generation of higher harmonics.
The above drawbacks are eliminated in the proposed device to improve the quality of power supply in three-wire electrical networks by increasing the reactive power control range and reduce the generation of higher harmonics.
This is achieved by connecting the controlled rectifiers SCR source of reactive power, connected in star, to the phases of the electrical network through the control winding controlled reactor, is provided by connecting the series-connected control windings controlled reactor and capacitor banks to the phases of uncontrolled three-phase rectifier bridge, loaded on the winding bias controlled reactor and a resistor .
 |
 |
 |
FIG. 1 shows a diagram of the electrical connections to improve the quality of power supply device in the three-wire electrical networks; FIG. 2 design is one phase of the magnetic system controlled reactor with nonmagnetic gaps; FIG. 3 Control block diagram of triac controlled reactor. The device comprises three driven reactor, each of which consists of two main coils 1 and 2 connected in series, in accordance with the inclusion of a longitudinal electrical network (Fig. 1). By common connection point of the windings 1, 2, 3 connected capacitor banks connected in a triangle and connected in series windings 4, 5 control. Other findings of the windings 4, 5 are connected to the control valve (triac) 6, connected in star, and the phases of uncontrolled rectifier bridge 7 via the capacitor banks 8. The rectifier bridge is loaded on the winding 9, 10 and bias resistor 11. The magnetic system of each managed reactor 12 made from nonmagnetic chetyrehsterzhnevoy gaps in each terminal (FIG. 2). At secondary winding cores placed one core 2 and windings 4, 5 control. On the extreme rods are winding 9, 10 management. |
measurement and control system triac 6 (Fig. 3) consists of a sensor 15, current (current derivative), connected to the output transformer 13, a current filter 16 of higher harmonics and the filter 17 voltage negative and zero sequence connected to the secondary windings of the transformer 14, the voltage converter reactive power 18 having a connection to the outputs of current transformers 13 and voltage transformer 14 and the voltage measuring unit 19 connected to the secondary windings of the transformer 14 voltage. Outputs measuring units 15-19 through the switch 20 and the analog-to-digital converter (ADC) 21 connected to the input of triac 22. The programmable controller 6 is controlled by the output of block 24, a pulse-phase control via a digital to analog converter (DAC) 23 connected to the output of the programmable controller 22 in accordance with the laid down in the controller program.
The device to improve the quality of power supply in three-wire electrical networks follows.
In the event of a short circuit in the electrical network is 15, current sensor operation (current derivative), under the influence of which the programmable controller 22 acts via the DAC 23 to the block 24, pulse-phase control. Provides full opening Triac 6. mag- with reactors that cause the flow of the rectified current through the windings 9, 10, is removed. The inductive reactance of reactors, depending on the main winding 1, 2 and included in accordance with the windings 1, 2 windings 4, 5 management increases dramatically, providing an effective limitation of short-circuit currents. After the disappearance (shutdown) Short circuit the unit returns to normal operation.
When fully closed symistors 6 ensures maximum magnetization of the magnetic system 12 reactors. Their inductive reactance bit. Condenser battery 8 outputs a maximum reactive power into the power grid. Condenser battery 3 provide the basic compensation of reactive power, which does not change over time. By varying the triac 6 a steering angle in dependence on transducer readings 18 and measuring unit 19, under the action of the block 24, managed by the controller 22, provide a change in the reactive power caused by the capacitor banks 8, the degree of magnetization of the magnetic system 12 controlled reactors and, hence, the voltage drop across the windings 1 2 reactor. Thus providing regulation of the load voltage and reactive power compensation.
Compensation voltage feedback and null sequences in the case of three-wire electric network asymmetry provides phase segregated controlled triac 6 under the influence of the block 24 according to the output signals of the controller 22 and the DAC 23 in accordance with the testimony of the filter 17, negative and zero-sequence voltage electrical network. Change subject to three longitudinal inductive element (coil 1, 2), three transverse inductive element (coil 4, 5), three capacitive transverse element (capacitor banks 8), inductive elements (windings 9, 10 bias) and an active element (resistor 11) , which have a cross through the inclusion of bridge rectifier 7.
Compensation harmonics provided by T-wideband filter, consisting of a main winding 1, 2 reactors and circuit comprising series-connected winding 4, 5 Control, capacitor banks 8, uncontrolled rectifier bridge 7 loaded to the resistor 11 and the winding 9, 10 bias. Adjusting the filter bandwidth is provided by changing the triac 6, the steering angle in accordance with the indications of the filter 16, acting through the switch 20 and the ADC 21 to the controller 22.
Changing the angle of the control triacs 6 under the influence of continuous output signal unit 24 through the DAC 23 in accordance with software algorithm embedded in the controller 22, depending on the sensor readings, and blocks 15-19 are connected through the switch 20 and the ADC 21 to the input of the controller 22.
Device to improve the quality of power supply in three-wire electrical networks made of well-known elements, produced by the domestic industry. It can find the most widely used for reliable and quality power supply of electricity consumers by carrying out reactive power compensation, harmonic compensation, voltage regulation, balancing current and load voltage and limit and short circuit currents.
The economic effect of the device can be achieved by improving the technical and economic indicators: reduction of electricity losses, improve service life of power consumers, reduce capital expenditures, reduce the damage caused by the unreliability of power supply by improving the quality of electricity and reduce the levels of short circuit currents.
CLAIM
DEVICE IMPROVING THE QUALITY OF POWER In three-wire electric networks, comprising a thyristor reactive power source with a controlled reactor core coil which longitudinally incorporated into the electricity grid, and the control winding cross included in the electrical network, characterized in that the thyristor source of reactive power controlled valves are connected in a "star "and connected to the phases of the electrical network control winding through the reactor, which are included in series with the capacitor banks connected to the phases of uncontrolled rectifier loaded to the reactor winding and the bias resistor.
print version
Publication date 15.02.2007gg
Comments
Commenting, keep in mind that the content and the tone of your messages can hurt the feelings of real people, show respect and tolerance to his interlocutors, even if you do not share their opinion, your behavior in terms of freedom of speech and anonymity offered by the Internet, is changing not only virtual, but real world. All comments are hidden from the index, spam control.