| 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 RU2294044
HOW TO PROTECT CONSUMERS OF ELECTRICITY FROM EXPOSURE higher harmonic components
Name of the inventor: Shpiganovich Alexander (RU); Shpiganovich Alla (RU); Bosh Violetta losifovna (RU); Dovzhenko Sergei Viktorovich
The name of the patentee: Lipetsk State Technical University (Lipetsk State Technical University)
Address for correspondence: 398600, Lipetsk, st. Moscow, 30, NIS LSTU
Starting date of the patent: 2005.08.24
The invention relates to electrical engineering, namely to methods for providing improved quality parameters for the electricity consumers affected by negative factors of the higher harmonic components of electricity. The technical result is to increase the quality parameters of electric energy to consumers. For this method to generate higher harmonic components of the current network, operating in opposition with the main network by higher harmonics.
DESCRIPTION OF THE INVENTION
The invention relates to electrical engineering, namely to methods for providing improved quality parameters for the electricity consumers affected by negative factors of the higher harmonic components of electricity.
Known methods for reducing the level of higher harmonic components of the electrical energy, comprising a power resonant filters, notch filters simple or complex combined filter (bandpass) serving to filter multiple harmonics. Produced power resonant filters 5, 7, 11 and 13 harmonics (IV Zhezhelenko higher harmonics in power supply systems of industrial enterprises [Text] / I.V.Zhezhelenko -. M .: Energoatomisdat, 1984, p.109). The principle of operation of such plants is based on the occurrence of resonance in their own resonant circuit tuned to a specific frequency. The filters can be installed in the network for the separation of linear and nonlinear loads (protective filters) or to absorb (shunt) current harmonics. Increased power efficiency is provided by using the power and resonance of filters as part of fast-compensating devices. The main disadvantage of this method, as shown by many years of their operation, are:
- Partial compensation of higher harmonics;
- Filtering only the higher harmonic component of a certain frequency (number);
- The inability to compensate for the higher harmonics of the sudden change in their spectrum.
This leads to increased heating of current-carrying parts, protection operation of electrical installations and damage sensitive microprocessor-based process control equipment.
As a prototype accepted method of increasing the quality of electric energy, comprising the isolation of the mains voltage harmonics voltage, but also the first harmonic determined voltage asymmetry straightening selected voltage harmonics, converting the rectified voltage into an AC voltage with a frequency equal to the first network harmonics, and the return of the AC voltage in the electricity network (Patent RU №2237334 C2, H 02 J 3/01, H 02 J 3/26. A method for improving the quality of electricity // publ. 2004). The disadvantages of this method are:
- Providing partial compensation of higher harmonics, bounded by the characteristics of filters, included in its composition;
- Filtering only a specific frequency range of higher harmonic components;
- The inability to satisfactorily compensate for the higher harmonics of the sudden change in their spectrum.
The invention solves the problem of improving the quality parameters of electric energy for consumers using power converters and other electrical equipment, which is a source of higher harmonics by full compensation for the higher harmonics due to the generation of the network of higher harmonic power components operating in opposition to the higher harmonics of the fundamental network, using energy mains, in which compensation is made.
To achieve the above technical result the proposed method, which includes the allocation of the first and higher harmonics of the network, used generator harmonics, which is controlled by a thyristor converter powered from the network, which carried out the payment of the higher harmonics.
Distinctive features of the proposed method is the generation of higher harmonics in the AC network managed spectrum, operating out of phase with the harmonics of the basic network.
 |
The proposed method is explained in Figures 1 and 2, which show schematic of a harmonic compensation curves and the output currents of the current transformer and input harmonic analyzer. Scheme 1 shows the measuring current transformer 1, the analyzer harmonic filter 2 of the first 3 harmonics, harmonic filter 4, controlled thyristor rectifier 5 and 6 installation. The inventive method involves the use of a measuring current transformer 1 (1), which serves to bring the line current to the value of up to 5 A, which is suitable for further transformation. The current transformer is connected to any phase of the mains harmonics due to the symmetry in all phases. For current transformer 1 are requirements of the minimum current and tracking error (accuracy class 0.5) and the lack of current transformation distortion at higher frequencies (up to 3 kHz). output current curve 1 shown in Figure 2a. Analyzer harmonic 2 (1) is used for analysis of higher harmonic components of the current network, which is a high-speed analog-to-digital converter connected to the current transformer 1 and serves to convert the information from the one in a digital form suitable for further processing. Analyzer harmonics corrupts the whole spectrum at higher frequency harmonics that are multiples of 50 Hz, and determines their level and the initial phase. By analyzer 2 are requirements of work at a frequency of 3 kHz. Given that are analyzed only the higher harmonic components of the network current of the current waveform must be obtained at the output of the transformer 1, the primary curve eliminate harmonic current network. For this purpose, the first harmonic filter is 3, which is a resonant filter tuned to the line frequency (50 Hz) (Figure 1). The device 3 is connected to the input 2 or one of its members. current curve at the output of 3 is shown in Fig.2b. For power compensation devices of the higher harmonics is an electrical network, which carried out the payment. Harmonic filter 4 is used to eliminate the influence of the higher harmonic components of the rectifier unit current at the electrical network. For the generation of higher harmonics in the network is managed by a cascade of fast thyristor converters 5 (1), which are powered by the mains. Controlled thyristor converter is a device which acts on the principle of the frequency inverter. Power 5 is selected within 1.2% of rated power network. For the rectification of alternating current network is necessary for the power supply 5 to use the power rectifier unit 6. |
 |
Manage the initial phase and the level of higher harmonics generated by 5, is carried out on the basis of feedback from the 2 (1), carried out by means of an electric network in which the payment is made. Control criterion is minimizing the level of harmonics at a specific frequency.
Higher harmonics that occur in the network, carrying out food-managed thyristor converters and rectifiers, have a constant range and offset 4.
To install structural elements are presented stability requirements for high voltage and safety of staff at high voltage.
CLAIM
The method of protection of electricity consumers from the effects of the higher harmonic components, including the allocation of the first and higher power harmonics by using the energy of electrical network, which carried out the payment, characterized in that, in order to provide compensation for the higher harmonic power components, generate the higher harmonic components of the current network, acting in opposition to the higher harmonics of the basic network.
print version
Publication date 05.04.2007gg
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.