Quality electricity - a major problem in many regions of Russia. Fluctuations of voltage and current are so large that in some cases lead to failure of an expensive home and other equipment. Reasons for lowering the voltage a great many: the distance from the substation, the presence of feeders powerful consumers, outdated and not designed for modern electrical cable, just next to the ongoing welding and much more. Low voltage network is dangerous for refrigerators, pumps and any engines. Increasing the voltage - the situation is less common but more fatal in effect, as a danger to all electrical equipment, without exception. The first sign by which to judge the faults in the network - a flashing or frequent burnout of incandescent lamps. The main indicators of power quality are determined by GOST 13109-97, which provides that, subject to these regulations is provided "compatibility of electric networks of general purpose power and electric network electric power consumers (receivers of electric energy). The rules of the standard are mandatory in all modes of power supply systems of general use, except for modes associated with unforeseen situations. However, the reality is much more complicated. About any safeguards can not speak, for example, in rural areas where there is a massive building of cottages, and where the substation and yard is extremely worn. In a survey of more than 300 objects in various places like the Moscow region and other close lying areas, made some analysis of really existing network quality. Year period - 30% of surveyed facilities tension was overstated by 15% compared to 220 W. At 25% strain ranged from 180-190 in the low to normal. At the remaining sites ranged from voltage 140 V to 210 V. The winter period. This concerned mainly with year-round residence. 80% of the surveyed sites voltage ranged from 160 to 230 V. At 20% free power did not rise above 180-190 V. Moreover, in three-phase phase mismatch reaches 30-40 V and more. Thus, we can draw a simple conclusion - the current state of the mains characterized by a significant deviation of its basic parameters - the voltage from the normative value of 220 V +10%, -15%. At the same time, should take into account the fact that Russian consumers are largely used electrical equipment of foreign manufacture. This primarily refers to devices such as refrigerators, pumps, air conditioners, boilers with automatic washing machines, etc., ie Devices that do not have the opportunity to take the producers of special measures to ensure that their work in a wide range of supply voltages. Reliable protection against poor power supply in most cases, voltage regulators. Voltage regulators - devices to automatically maintain a network of consumer voltage of 220 V + 3 -7%: raise lower and lower over-voltage, disconnect the power supply in case of emergency increase or decrease the input voltage (emergency jump in power). In other words, the device protects equipment from voltage, high voltage pulse rise and fall of voltage. Voltage regulator automatically maintains the load voltage level of 220 V with deviations from the norm value of the input supply voltage. It protects any, even the most capricious of equipment (plasma panel, for example) from a sudden significant change in voltage sources. There are two ways of using stabilizers. In the first case, the stabilizer is installed on the entire load, which is in the house. In the second case, fed 3.2 weakest appliance. Naturally, the price of the stabilizers used in the first and second option would be significantly different. To make a decision, you simply calculate the total power protects the device and compare it with your financial capabilities. When calculating the total power of the protected electrical equipment must take into account simultaneity factor for their inclusion. Let us explain this with an example: you have summarized the entire load, which consists of 10 light bulbs of 100 W + washing machine - 2 kW + fridge and a kettle - 2,5 kW + iron - 2 kW + microwave oven, etc. and received as a result, we assume 10 kW. However, as a rule, at a time when the wash, iron is not used, so the calculation can not include both the consumer and only one - the washing machine. Or, for example, when the house party and lit the light in all rooms, as well as running the entire video and audio equipment, it is usually at this time no one washes. Therefore, the washing machine on a case of the calculations can be safely deleted. That such arguments allow you to enter into the calculations the coefficient of simultaneous operation. As a result, its introduction may well be that the total power of consumers in the home of 10 kW while the power is switched on no more than 5 kW. True, it does not mean that you have enough of the stabilizer 5 kW. Stabilizer should be chosen with a small margin, and therefore in this case, you should choose the nearest more powerful - 7,5 kW. Not least the next stage - the choice of stabilizer in terms of performance. Delivered stabilizers can be divided into three main types: electromechanical, step and ferroresonance. They each have their pros and cons. Electromechanical servo systems. The basis of the scheme is adjustable autotransformer, included in the primary winding of the booster transformer. Secondary winding turns in the gap phase of the network. This scheme allows you to smoothly adjust voltage without interruption and without phase distortion sine wave. Voltage sufficiently compact and suitable for any type of load. The benefits of voltage regulators on the basis of the electromechanical system are: - high precision holding the output voltage 220 (1%) - smooth adjustment speeds from 20 to 50 V / sec (light bulb flashes will not) - the absence of noise at work and distortions Waveform - a good load capacity - a wide range of 100-280 V. correction is used in power networks cottages, banks, industrial buildings, medical facilities. Some models are designed to work in conditions of very low voltage (100-130 V instead of 220, where no other voltage regulator does not work). Power voltage stabilizer 4 KVA to 150 KVA. Step-voltage regulators - the safest and most massive type of universal stabilizers. The scheme is based on switching tap autotransformer using electronic switches. Output voltage regulator varies in steps. Interrupting voltage switching among different models ranging from 2 to 12 ms (5.7 ms for the relay). Voltage correctors have a wide input voltage range, high accuracy of output voltage, not distort the external network and operate reliably under any load changes, provide effective protection against overload, short circuit and impulse noise. This type of voltage regulator is suitable for real Russian environment and can be used to stabilize power supply and protection of consumer and industrial equipment, including computers, communications equipment, etc., as well as for the integrated supply of industrial equipment, cottages, apartments and offices. Power of 10 VA to 100 kVA. Ferroresonance voltage regulators - with the redistribution of stress. They are reliable, able to stabilize the line and phase voltages and provide instant performance. Able to work outdoors. The drawbacks include increased noise at work. Power: 10 KVA to 100 KVA. Modern stabilizers are usually equipped with more and more protection, that is, if voltage does not allow the stabilizer to give the required load voltage, it will disable it and automatically turn only when the voltage is deemed safe for operation connected to it, electrical appliances.
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