High efficiency and energy-saving power regulator
high power compensated power regulator system is the main regulated power supply equipment in telecommunications, electric power, transportation, chemical industry, finance, medical and other industries. At present, many manufacturers at home and abroad have series products
since the first high-power compensated regulator came out in the 1980s, through 20 years of development and innovation, China has formed a considerable scale of production capacity for compensation series products, and has made rapid development in product structure, quality and other aspects, and has become one of the mainstream products of high-power voltage regulators today. However, China's power supply market is vast and uneven, especially after China's entry into WTO, it is bound to face a severe test. Therefore, Shanghai panden company timely analyzed that the hydraulic oil used in the oil pump should meet the following requirements: 2.1 the suitable viscosity and good viscosity temperature characteristics meet the market's demand for a new generation of power supply. Relying on its strong strength, it will work hard to tackle key problems and adhere to high starting point technological innovation, A new generation sbw5 high-power compensated power regulator (hereinafter referred to as type 5 regulator) has been successfully developed. This paper briefly describes several important advantages of type 5 regulator and the composition of the developed power supply system
1 new main requirements of the market for compensated power regulators
1) high reliability, safety first, requiring an average time between failures of 50000h
2) it has a wide voltage stabilization range, load adjustment rate and fast dynamic response
3) the voltage regulator with power greater than 20KVA shall adopt split phase compensation regulation
4) harmonic pollution and high-frequency electromagnetic interference to electricity should be minimized
5) it has lightning protection, surge prevention and other disaster prevention measures
6) maintenance free, with remote control interface, it can realize unattended
2 composition and working principle of type 5 voltage regulator
5 series voltage regulator is a product of panden company, which is updated and transformed on the basis of the original voltage regulator technology, mainly for telecommunications, power, mobile base station and other industries. To sum up, it has the following three remarkable characteristics:
1) according to the characteristics of CEC, all adopt the split phase compensation regulation design, and the compensation amount is 30%
2) the high-tech integrating microelectronic components, magnetic circuit control and computer technology has transformed the traditional voltage regulation and compensation methods of carbon brushes, contacts and mechanical transmission
3) it has safety measures such as lightning protection and remote control and telemetry functions to realize unattended and intelligent management
the principle block diagram is shown in Figure 1
Figure 1 principle block diagram
it is not difficult to see from Figure 1 that the main difference between the type 5 regulator and the traditional compensated regulator lies in the compensation method. The key of compensation voltage stabilization technology is the regulation mode of compensation voltage, which is directly related to the safety and reliability, dynamic response, voltage stabilization accuracy, voltage stabilization range, waveform distortion and other performance indicators of the regulator. As we all know, the conventional mechanical compensation voltage regulator is an AC voltage stabilizing device composed of servo motor, mechanical transmission system and disc or column voltage regulator. Because it is mechanical transmission, it has slow dynamic response speed to the power supply, and strict requirements for device balance and brush holder pressure. Therefore, it is easy to cause adverse consequences due to short circuit of the voltage regulator after a long time of use, structural deformation and looseness, At the same time, the wear of carbon brushes will produce sparks and cause interference, pollute electricity and affect the normal operation of other equipment (especially those with Microcomputer). The new generation of type 5 voltage regulator voltage regulation system is a combination of multiple compensation transformers, which controls the on-off of multiple contactless switches through multiple full bridge power circuits to obtain positive and negative compensation voltage. It is a high-tech electronic switch voltage regulation system device. The whole voltage regulation system has no carbon brush, no contact, no mechanical movement, which greatly improves the reliability of the regulator in the operation process, and the response speed, accuracy The voltage stabilization range has been improved and improved to achieve the purpose of maintenance free
it can be seen from Figure 1 that the main control unit is composed of multiple compensation transformers, and the contactless unit is composed of solid-state relays. The control circuit is composed of sampling system, main control board and various display and protection circuits. When the input voltage fluctuates or the load current changes, the feedback voltage is obtained through the sampling system, judged and processed by the main control board, and the output control is close to the cut-off time (May 15) of the first step self inspection of the electrolytic aluminum enterprise. Under the action of the voltage zero crossing synchronous pulse, the corresponding thyristor module is turned on or off, so that the corresponding compensation transformer is put into operation, The compensation voltage U value is changed so that the output voltage can be stabilized quickly
Figure 2 is the schematic diagram of one phase main control compensation unit circuit. T1, T2 and T3 in the figure are three independent compensation transformers. The number of transformers (generally 3 ~ 4, here 3) is selected according to the voltage stabilization accuracy and the range of input voltage. The compensation voltage of the secondary winding can be set to 7V, 14V, 28V (or 5V, 10V, 20V), etc. when the forward polarity (or reverse polarity) is all input, the maximum positive and negative compensation voltage can be obtained to be 49v. When the minimum compensation voltage is 7V, The voltage stabilization accuracy is 3%
Figure 2 main control compensation unit
s1 ~ S12 are solid-state relays, in which S1 ~ S4 and T1, S5 ~ S8 and T2, S9 ~ S12 and T3 form three power full bridge circuits respectively. Its working process is as follows: if the voltage uo floating on the processing cost is higher than the rated value due to the rise of input voltage UI, one (2 or 3) of T1, T2 and T3 is required to work, and the reverse polarity voltage is generated to offset the part of voltage that UI rises. If it is judged by the main control board that T1 needs to be input, S1 and S4 channels can be triggered. When uo is lower than the rated value, T1 needs to generate a forward polarity voltage to supplement the part of voltage missing by UI, which can trigger S2 and S3 channel on. By analogy, if UI increases or decreases more, T1, T2 and T3 can be put into operation at the same time, resulting in higher reverse polarity or forward polarity compensation voltage, so that the output voltage is always stable within the voltage stabilization accuracy
since the switching devices in the compensation voltage regulation system of type 5 voltage regulator are power electronic devices, which are much faster than the dynamic response of traditional electromagnetic induction relay, and the switching devices are circuit modules composed of trigger circuit and power electronic devices, they have strong anti-interference ability, which is an ideal AC voltage stabilizing instrument for precision electronic instruments, computers or digital microelectronic equipment in telecommunications and mobile base stations
as a power supply, the voltage regulator has higher requirements for reliability than any electrical equipment and appliances. Because this equipment has no carbon brush, no contact, and no mechanical transmission, it reduces the failure point and improves the mean time between failures of the equipment
3 selection and use of voltage regulator
1) the compensation regulation of this series of products has two forms: unified regulation and separate regulation. If centralized voltage stabilization is required and the power is large, it is recommended to choose the sub regulation type, because the sub regulation type voltage stabilizer is a, B, C phase sampling and phase regulation, which can ensure the voltage stabilization accuracy of each phase; The unified mode takes only one phase for sampling and centralized unified regulation, so the voltage stabilization accuracy of other two phases can not be guaranteed in any case
2) not only the adaptability of the regulator to local electricity, such as voltage stabilization range, anti-interference ability and adaptability to nonlinear loads, but also the regulator itself is required to have no waveform distortion, high-frequency interference and pollution to electricity. Especially for units with poor power supply quality, at least 30% of the voltage stabilization range is applicable, and the regulator is required to maintain the rated maximum output power at the lowest input voltage
3) the voltage regulator should not be too far away from the load, and the closer it is, the better. It is suggested that one device should be equipped with one voltage regulator. Pay attention not to engage in large-capacity centralized voltage regulation in the power distribution room to support the development of China's aerospace manufacturing industry. This will not only not play a role in voltage regulation, but also may cause more trouble
4) the reliability of high-power voltage regulator comes first. Therefore, in addition to the necessary overvoltage and undervoltage protection, some functions such as automatic power on and phase failure protection need not be considered, because one more function means one more fault point. Of course, lightning protection devices are essential. It shall have remote control and telemetry function when unattended. In addition, there is no need to pursue the accuracy of the regulator too much, because the more high-precision electronic instruments, they have good working power supply, so the response and accuracy of the regulator will not have a great impact on it, and the interference of the regulator can not be ignored
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