3 phase voltage. Linear and phase voltages
Otrimannya triphasic struma.
A rich-phase system is called a system snake struma, which is made up of a few lances, in some e.f.s. Dzherela energії mayut the same frequency, but destruction between them in phase. Single-phase lanceug in such a system is called a phase. Skin e.r.s. you can work with your independent lancer and don’t be tied to other e.d.s. And here the electrical system is called unconnected. Widely zastosuvannya practical otrimali po'yazanі rich-phase systems, yakі okremi phasei elektrically connected between themselves.
Por_vnyano with a single-phase rich-phase strum may have a number of advantages. For the transmission of one and the same tension, less darts are needed. The robotic engines and fittings of the strum have a magnetic field, which wraps around, created by unruly coils or windings.
Rice. one
Three of the systems of the rich-phase struma became very wide, having practically eliminated the three-phase struma. The coloring of a three-phase struma can be explained as follows. Like in a uniform magnetic field (small 1) place three turns, ruffled under the hood 120° one to one, and wrapping them with a constant windshield, the coils will induct eds, as they will also be put in phase on 120°. In industry for the removal of a three-phase strum, three windings are wound on the stator of the generator of a strum, one is damaged 120°. These windings are called generator phases.
Rice. 2
Z'ednannya star. The last phase windings of the generator are either slowed down in such a way that the ends of the windings are closed at one central point, and the cob of the windings are connected to the linear drotiv, taking away the rank of a star (Fig. 2). In this rank, mi Bachimo, that with the adoption of three single-phase systems of a three-phase system, connected in a star, the replacement of six wires will require only a chotiri. Mentally z'ednannya with a star is signified by a sign Y . Krapki, at some of the ends of the phase windings, are called zero, and the conductor, which is connected to them, is called zero or neutral. Three darts, which connect the free ends of the generator phases with the ends of the slow phases, are called linear.
In case of equal navantage of three-phase symmetrical system zero wire not needed; all tension can be transmitted by three wires. However, when included in the electric lance single phase dampers it is not possible to reach equal phase entanglement. Therefore, in such situations, a zero wire is necessary, if you want to cut one half of the line cut.
Rice. 3
With such a connection, the end of the first phase is connected with the ear of another, the end of the other - with the ear of the third, and the end of the third - with the ear of the first phase, and before the point of the end of the phases, linear darts are connected (Fig. 3). Z'ednannya tricutnik mentally designate a sign Δ .
When the generator phase is connected by a tricot, a closed circuit is established with a small support. If the windings are connected incorrectly, e.r.s. you can get bigger. With a small support to the circuit, a mode close to a short flicker can be restored.
When connected with a tricot, the skin phase winding is created line voltage. The phase of the voltage in this mode is the same as the linear one. Z'ednannya zastosovuyt for illuminating and power navantazhen.
In the engines of a three-phase struma, it is necessary to make a sound of six windings of three windings;
In electrical installations of living quarters rich apartment houses, as well as in the private sector, three-phase single-phase lines. View of the cob electric chain exit the power plant with three phases, and most often up to living houses the connection of the lifeline is itself three-phase. Dali won't be cleared on the edge of the phase. This method is designed to achieve the most efficient transmission of an electric stream from a power plant to the point of recognition, as well as to reduce costs during transportation.
To determine the number of phases in your apartment, enough rose shield, roztashovaniya on the skhodny maidanchik, or right in the apartment, and marvel, skilki wires go to the apartment. If the mesh is single-phase, then there will be 2 -. Another possible third wire is grounding.
Three-phase lines in apartments are rarely blocked, at times the connection of old electric stoves with three phases, or pushing navantagen at the sight of a circular file or scorching accessories. The number of phases can also be determined by the magnitude of the input voltage. A 1-phase line has a voltage of 220 volts, a 3-phase line between phase and zero has 220 volts, between 2 phases - 380 volts.
Vіdminnostі
If you do not take into account the importance of the number of conductors and the connection scheme, then you can determine other features, such as three-phase and single-phase connections.
In times three-phase mesh vivlennya possible peroxide of phases through nerіvnomіrny podіl on phases of navantage. On one phase, there may be connections for an exhaust heater or pectin, and on another TV set cleaning machine. This is the cause of this negative effect, which is accompanied by asymmetry of voltages and streams in phases, which pulls along the faults of the butt fittings. In order to avoid such factors, it is necessary to separate the phases before laying the wires of the electric line.
For a 3-phase line, more cables, conductors and chemicals are needed, which means pennies do not spare.
Possibility of a single-phase butt line for tightness is significantly less than for a three-phase one. What is planned hard work and pobutovih outbuildings, power tools, it is important to bring to the booth or the apartment a three-phase line of living.
The main advantage of a 3-phase treadmill is a small drop in voltage equal to a 1-phase treadmill, for the sake of the same tightness. It is possible to explain, that in a 3-phase streak, the conductor has fewer phases, lower in a 1-phase streak, and there is no strum on the zero streak.
Advantages of 1-phase mesh
The main advantage is economy and victories. Three-wire cables are used in such tethers, whereas in 3-phase tethers there are five-wire cables. In order to set up protection in 1-phase lines, it is necessary for a mother to have one-pole protection, at that time, in 3-phase lines, one cannot do without tripoleic automatic devices.
At zv'yazku z tsim the dimensions of the zakhist are also significantly adjusted. Navit on one electric automatic already saves two modules. And for the dimensions, it should be close to 36 mm, which is signifi- cantly in line with the placement of automatic devices. And when installed, the economy of space becomes over 100 mm.
Three-phase and single-phase lines for a private booth
Vitrata electricity of the population is constantly moving up. In the middle of the last century, private booths were full of small butt outbuildings. Today, for each plan, we have another picture. Pobutovі spozhivachі energies in private huts do not multiply every day, but schogodini. That's why there is no need for food at your private volunteers, as you choose the means of living for connection. Most often, in private spores, life lines are built with three phases, and in single-phase lines they are built.
Ale chi varto is a three-phase measure of such an advantage in the installation? It’s important for someone who, having connected three phases, will be able to build up a great number of outbuildings. Ale, do not hesitate to come out. The most admissible tension is indicated in the minds of the connection. Call this parameter to set 15 kW for all private households. In the case of a single-phase mesh, the parameter is approximately the same. It is clear to him that there is no special benefit for the effort.
Ale, it is necessary to remember that although three-phase and single-phase lines can cause equal tension, then for a 3-phase line it is possible to stagnate, since tension and strum are spread over all phases, then, less navantage around the conductors of the phases. The nominal value of the strum of the machine for a 3-phase line will also be lower.
The value of the difference is great, which is much larger for a 3-phase measure. It is worth laying in a three-phase expansion, which may have dimensions larger than a single-phase one, and also the automatic introduction will take more space. Therefore, a rozpod_lny shield for a three-phase treadmill is folded into a few tiers, so that there is not a lot of tiara.
But the triphasic livelihood has its own advantages, which are manifested in the fact that it is possible to connect the triphasic intake of the struma. They can be and other potty extensions, which are the main three-phase fence. operating voltage 3-phase lines are more expensive than 380 V, which is higher, lower in a single-phase type, which means that the power supply of the electrical safety will have to add more respect. So on the right and with fire safety.
Small pieces of three-phase mesh for a private booth
As a result, it is possible to see a small amount of a three-phase fence for a private booth:
- It is necessary to take technical knowledge and allow for the connection of measures to energy supply.
- There is a danger of being wounded by a strum, as well as a danger of sleeping through an increased voltage.
- The values of the dimensions of the distribution board for the introduction of housing. For the rulers of the zamіsk houses, such a short time is not possible great significance, to the fact that they have a month.
- Necessary installation at the visible modules on the inlet shield. In triphasnіy merezhі tse especially important.
Benefits of a three-phase meal for private houses
- It is possible to expand the transition step by step in phases, in order to overcome the phase imbalance.
- You can connect to the measure of exhaustion three-phase calming energy. This is the most important advantage.
- Changes in the nominal value of devices on input and lower input.
- In the case of poor conditions, it is possible to reach the company's permission for energy supply to increase the allowable maximum pressure level of the electric power supply.
As a result, it is possible to build visnovoks, which is practically recommended for the introduction of a three-phase living system for private houses and houses with a living area of over 100 m2. Three-phase eating is especially suitable for these rulers, as they choose to install a circular saw, a scorching boiler, and variously drive mechanisms with three-phase electric motors.
For the rest of the rulers of private houses, go to the three-phase meal without obov'yazkovo, shards can create more than additional problems.
In the present hour, in the whole world of the widest nabeul, the so-called three-phase system of the strumu was found and broken up in 1888 by the Russian electrical engineer Dolivo-Dobrovolsky. Vіn first constructing and inducing a three-phase generator, three-phase asynchronous electric motor that three-phase power transmission line. This system ensures the most efficient transmission of electrical energy through wires and allows you to simply add a handy device to the robotic electric motor.
A three-phase system of electric lines is a system that consists of three lines, in which there are changes in the EPC of one and the same frequency, disruption in phase, one at a time, one for 1/3 of the period (j \u003d 120 °). The skin of the lancets of such a system is called a phase, and the system of three broken streams in phase in such lances is called a three-phase stream.
Maintenance of a constant phase noise between the output voltages of three independent generators can be completed by folding technical tasks. In fact, for the production of three streams, broken in phase, three-phase generators are vikorated. To serve as an inductor at the generator is an electromagnet, the winding of which is to live post-strum. The inductor is the rotor, and the yakir of the generator is the stator. Leather winding of the generator є independent strum generator. Having arrived the darts to the ends of the skin, as shown in the little one, we would take three independent lances, the skin for some time to revive the energy and other priymachi, for example, electric lamps. And here the transfers of all the energy six drotiv. It is possible, however, to connect the windings of a three-phase struma generator together in such a way that you can get around and wind three wires in order to protect the electrical wiring.
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At the same time, the equal ambition of all three phases The strum at the zero dart is equal to zero and it is possible not to beat it. At asymmetric ambition the strum at the zero dart is not equal to zero, and is signifi cantly weaker, the lower strum at the linear dart. Therefore, zero wire can be thinner, lower phase.
The windings of a three-phase generator can be connected with a tricotnik. With all the end of the skin windings, with the onset of the spadix, so the stinks make up the closed trikutnik, and the linear darts come to the tops
Zmist:One of the options for systems of rich-phase electric lances is a three-phase lance. In rich-phase electric lances, there are sounds of sinusoidal electric motors with the same frequency. The stench winds up one kind of one in phase and they are created in the form of a wild energy dzherel. In triphasic lancers important parametersє phase and line voltage, which are controlled by their electrical characteristics.
What is the phase
The skin part of the rich-phase system, which has the same characteristics of the struma, is called the phase. Therefore, the purpose of the phase can be twofold in electrical engineering. First, like a value that changes sinusoidally, but in a different way, like a small part of a system of rich-phase electric coils. The number of phases is determined by the name of the lances: two-phase, six-phase and in.
The widest lances in modern energy are three-phase. They have a number of advantages over other species of lancers, both single-phase and rich-phase. The stench is economical in the case of the generation and transmission of electricity. Trooch phase voltage wink afterward wrapping the magnet in the middle of the coil. With yoga help to do it just settle down in a circle, what to wrap around, what to take care of the robot asynchronous motors. Dane is a sight, like EPC or otherwise, electrical breaking force induction.
The magnet that wraps around is called the rotor, and the coils, spun around, make up the stator. Changed voltage to go through the way of transformation constant voltage, If a straight line takes on a sinusoidal configuration with positive and negative values that change.
The change of the magnetic flux is driven by the rotor wrapper, which causes the change in voltage to be adjusted. The stator has three coils; electric lanceug. The skin cat is pushed forward one by one at 120 degrees on the stake. Under the influence of the magnet, what wraps around, in all the cats, the blame is the same changing voltage between phases in a three-phase line.
Three-phase lances give the possibility to take off two operating voltages on one installation - phase and line.
Phase and line voltage in three-phase lances
The phase of the voltage vinikaє between the cob and the end of the phase. Otherwise, it is important to determine how the voltage is between one of the phase wires and the neutral wire.
Linear - it is defined as interphase or interphase - which is caused by two wires or by the same windings of different phases.
Looking at the phases and line voltages and streams, it should be noted that the indicator of the phase voltage becomes approximately 58% of the line parameters. In this order, for the normal minds of exploitation, the indications of linear however and shift phases by 1.73 times. Tobto, as a linear voltage of 380, why the phase can not be assigned for the help of this coefficient.
In a three-phase line, the voltage, as a rule, is estimated according to the data of the line voltage. For three-phase lines that enter the substations, a line voltage of 380 volts is installed. Tse vіdpovіdaє phase 220 volts. For three-phase wire lines, the nominal voltage is indicated by the values of both values \u200b\u200b- 380/220 V. Tse means that such a line is connected like a 380-volt wire, and single-phase - for 220 volts.
The most wide nabula three-phase system 380/220 volts is grounded with a zero wire. Single-phase electrical appliances for 220 volts are connected to a line voltage between a pair of phase rods. Three-phase electrical appliances are connected to three different phases. In the rest of the fall, there is no need for a zero dart, with which there is a risk of strum attack, if the insulation is destroyed.
Vіdminnіst іnіynoї napruzі vіd phase
First of all, to consider the practical values of these parameters, it is necessary to know exactly how the linear voltage is distinguished between itself. Pevna interfacial voltage in triphasic lanceug can be connected either between two phases or between one phase and a neutral wire. Similar interrelation becomes possible through the choice of the scheme of a chotiriprovid triphasic lancet. Її main characteristics є strain and frequency.
The voltage, which is due to two phase conductors, is considered linear, and between the phase and zero phase conductors. The linear voltage is adjusted for the flow of air and other parameters of the three-phase stake. Before such circuits, it is possible to connect not only three-phase contacts, but also single-phase, for example, various butt fittings. The nominal value of the line voltage becomes 380 U. Sometimes it changes under the influence of various officials, which are at the local line. In this way, all the main differences between both types of voltage are related to the methods of winding windings.
The greatest breadth of the nabula of the linear voltage, through the safe vikoristannya and the handy division of the line. For this purpose, a multimeter is sufficient, as well as the design of the characteristics of the phase voltage, it can also be used to vary the voltage of voltmeters, sensors in the stream and other special accessories.
The control of that virіvnyuvannya tsgogo parameter zdіysnyuєtsya for help. This attachment ensures the improvement of this indicator on the normative level, in addition to the number of wines, it normalizes and increases the voltage.
Variable line and phase voltages
The classical butt of the variation of the linear and phase voltages is taken into account by the voltage that the variation occurs at startup three-phase generator. Yogo construction includes the first secondary windings, yakі can be z'єdnuvatsya zіrkoy or trikutnik.
The "trikutnik" scheme transfers the beginning of the first phase with the cob of the other. In addition, the leather phasnian guide traverses with the line darts of the jerel strum. As a result, the strums are vibrated, and the phase voltage becomes equal to the linear one. For such a scheme, electric motors and transformers are connected.
The second option is the "zirka" scheme. In this case, the cob of all windings is connected to one line for an additional jumper. In this way, in the windings there is a stream with the characteristics of the lines, and the interphase voltage is to enter into the interaction with the active contacts.
Mіzh two phase wires, іnоdі yogo zgaduyut yak міzhазне or міжазне. The phase is affected by the voltage between the zero wire and one of the phase wires. In normal operating minds, the line voltages are the same and reverse the phases by 1.73 times.
Operating voltage of a three-phase lance
Three-phase lances have a number of advantages in parallel with rich-phase and single-phase ones, with their help, you can easily take away the wraparound circular magnetic field, as if ensuring the operation of asynchronous motors. Napruga triphasic lantsyuga otsіnyuyut by її lіnіynomu napruzі for vіdhodyat od pіdstantsіy lіnіy Yogo vstanovlyuyut 380 scho vіdpovіdaє napruzі the phase 220 V. For poznachennya nomіnalnoї naprugi trifaznoї chotiriprovіdnoї MEREZHI vikoristovuyut obidvі quantities - 380/220 V, pіdkreslyuyuchi CIM scho not to pіdklyuchatisya only three-phase extensions, rated for a nominal voltage of 380 V, and single-phase - for 220 V.
A phase is called a part of a rich-phase system, which has the same characteristic of the struma. Depending on the method of joining the phases, there are three similar dignified three-phase stake voltage. The stench zsunutі vіdnosno one one in phase per cut, which becomes 2/3. A choti-piped lansyug, crim has three linear voltages, and also three phases.
Rated voltage
The widest rated voltage Priymachiv zminny struma є 220, 127 і 380 V. Voltages 220 і 380 In most cases they are used for living industrial outbuildings, and 127 і 220 - for butovih. All fumes (127, 220 and 380 V) are charged by the nominal voltages of the three-phase line. Їх availability at chotiriprovidnіy merezhі gives the possibility of connecting single-phase receivers, like insurance for 220 and 127 V or 380 and 220 V.
Power supply
The largest extension of the three-phase system 380/220 V from a grounded neutral, prosthetics are being developed for other ways to distribute electricity. For example, in a row settlements you know three-phase system from ungrounded insulated neutral that line voltage 220 V.
In this case, zero wire is not needed, but the damage electric jet in case of damaged insulation, it is lowered for the account of an ungrounded neutral. Triphasic adopters connect up to three phase darts, and single-phase - to the line voltage between any pair of phase darts.
