The hottest POWERBOSS intelligent economizer and i

POWERBOSS intelligent economizer and its working principle

I. Introduction

motor is the largest power consumer in the world, using about 70% of industrial electricity. Electric motors are also the world's largest energy wasters. The failure of intelligent matching of motors can actually increase the annual production capacity of metallurgical grade alumina by 500000 tons, and the power consumed is wasted. At present, no matter which power-saving company claims to have which power-saving technology, its basic power-saving equipment is frequency converter

however, no one is perfect and no gold is pure! Frequency converters are powerless in some fields because of their short hands. They either lose their function or are greatly discounted! For example, for equipment such as concrete mixers, injection molding machines, pumping units, etc., where the load requires constant speed but the load weight is constantly changing, the frequency converter is useless! On escalators in shopping malls and transmission belts in factories, the output of frequency converters is greatly reduced! Moreover, because the frequency converter requires to change the circuit of some equipment, there is a fault source, which is very unpleasant to users! As well as the large volume of the frequency converter, requiring heat dissipation space, wiring trouble, etc., which also brings trouble for its installation in some occasions—— In response to the above situation, SOMAR International Ltd. of the UK launched the intelligent energy saver of poweross, also known as power saver. It complements the shortcomings of the frequency converter. In the process of using the electronic tension machine, our frequency converter is left-hand and right-hand, complementing each other's advantages, and jointly completing the power-saving mission of motor transformation around the world

powerboss products have passed CE certification and EU EMC certification. In addition, POWERBOSS has been tested to comply with UL 508c/2000, and has obtained the ETL mark of the United States and Canada

on August 7, 2007, at North China Electric Power Research Institute, the POWERBOSS intelligent economizer, which has been brewing for a long time, officially passed the certification of domestic authoritative technical experts. North China Electric Power Research Institute, electric machinery science research association, Beijing Electric Power Association, and power supply companies under North China Electric Power attended the meeting, and made speeches and statements on the two major technical points of POWERBOSS economizer (soft start and energy-saving optimization), fully recognized and affirmed that this new generation of power-saving and environmental protection products will have a further and longer development path, and POWERBOSS will supplement the shortcomings of frequency converters, It has become a basic equipment for motor power saving in China, and has brought motor power saving to a new level

at present, POWERBOSS intelligent energy-saving products have branches and agent centers in 105 countries and regions around the world, and are being sold, installed and used

in China, many successful cases have been completed in only one year

for example:

Shandong Shengli Oilfield, one of China's largest oilfields, has an average power saving rate of 25% after installing the POWERBOSS on its 45KW pumping unit

after installing POWERBOSS, the power saving rate of 8 9kw escalators in the famous Xidan shopping mall in Shunyi, Beijing is as high as 35%

Hubei provincial energy conservation monitoring center installed POWERBOSS for the 22KW concrete mixer of its subordinate enterprises, with a power saving rate of 17%

there are more than 20 15kw injection molding machines in a large electrical appliance factory in Shenzhen, with a power saving rate of 24% and a return period of 12 months. And the original setting parameters of injection molding have not changed at all

after installing POWERBOSS, more than 10 100 ton punches in an electric tool factory in Yongkang, Zhejiang province saved 26% of power consumption

six 7.5kW and nine 11kw compression condensers in the cold storage of Shenzhen Luohu edible fungus factory have been tested for a long time, and the power saving rate is as high as 25%

several 37KW circular saw stone cutting machines of Guangdong Zhongcheng stone company have an average power saving rate of 16.9%

II. The difference between the power saving principle of POWERBOSS and the frequency converter

(I) the power saving principle of POWERBOSS:

powerboss power saving controller can automatically monitor the load condition of the motor, supply the most appropriate voltage and current to the motor according to the actual load of the motor, effectively solve the power saving problem of the motor under no-load, light load and variable load conditions, and does not affect the anti overload ability of the motor, This is a new technology and equipment to ensure the reliable and stable operation of the equipment carried by the motor

like ordinary buffer start-up period, POWERBOSS uses thyristors to accurately control the input voltage. The characteristic of thyristor is that when it senses a pulse, it will quickly change from "off" state to "on" state until the coefficient is reduced to zero. This principle is also called self commutation. With the control of thyristor on and off at each power supply half chord wave (voltage close to 0), the current passing through the thyristor can be controlled. When the starting power is closer to the end of the power supply chord wave, the allowable current is less. When the starting power is closer to the beginning of the power supply chord wave, the allowable current is greater. Citing this principle, connect the two thyristors in an anti parallel way. Therefore, powe has the "opinions of the State Council on strengthening and improving fire protection" in the State Council document No. 46 on December 30, 2011 and the newly issued "Regulations on fire protection supervision and management of construction projects" on July 17, 2012. Rboss can control the opening and closing of thyristors and supply the most applicable voltage required by the motor at that time (see the figure below) For example, delaying the start point of each half chord wave within a specific time and then gradually decreasing the delay time will increase the voltage supplied to the motor from a small number to the maximum. Because the torque of the motor is proportional to the square of the power supply voltage, powerbus controls the starting torque of the motor by controlling the voltage to the motor through the thyristor, so that the motor can smoothly accelerate to the maximum torque within the preset time, so as to achieve the purpose of soft start of the motor

powerboss does not need to change the original parameters of the device, and there is no constraint on the reference range. The installation of POWERBOSS will not affect all the original working states of the device

but the use of POWERBOSS brings other related benefits:

it reduces the mechanical strain of the motor, more effectively reduces the maintenance cost of the motor equipment, reduces the heating of the motor, and extends the service life of the motor

moreover, POWERBOSS can be connected with remote controller and microcomputer port, which can easily realize automatic remote control and improve the automation degree of equipment

powerboss adopts intelligent microprocessor control. Under light load, the voltage of the motor automatically drops to the minimum demand, while the speed remains constant. If the load increases, the voltage will rise automatically to prevent the motor from stalling

we know that the current that maintains the operation of the motor consists of two different parts: load or resistive current (IRI) and inductive or excitation current (IMI). When the load of the motor decreases, some parameters will change, and the phase angle synthesized by the resistive current (IR2) that produces the load torque and the relatively constant inductive current (im2) will increase, as shown in the figure below: the controller reduces the inductive current (IM3) by reducing the supply voltage of the motor, which plays the role of making the phase angle close to the original size, thereby reducing the hysteresis loss

under light load, the core loss caused by resistive current will also be reduced with the decrease of voltage, so the power consumption of the motor will be effectively reduced. In fact, the power savings obtained by reducing the voltage will be rapidly reduced with the increase of load

powerboss reduces the voltage of the motor by cutting the voltage waveform. When the voltage of the motor is reduced, the magnetic loss is correspondingly reduced, and the active and reactive losses are correspondingly reduced. At the same time, the power factor of the motor is increased, the stator current of the motor is reduced, the power supply line loss with the quadratic positive ratio of the current and the copper loss of the motor winding are significantly reduced, the iron loss of the motor is reduced, and the power of the motor is increased

(II) the difference between the working principle of POWERBOSS and frequency converter:

the working power-saving principle of POWERBOSS is mentioned above. Now let's see the difference between the working principle of POWERBOSS and frequency converter:

simply speaking, the frequency converter achieves the purpose of power saving by changing the frequency of power supply to the motor, while ensuring that the power supply changes in proportion to the frequency, so as to change the output torque of the motor. The POWERBOSS does not change the frequency of the power supply. It monitors the change of the phase angle between the voltage and current transmitted to the motor through the preset detection program in the chip. This phase angle changes constantly with the load change of the motor, that is, the power factor of the motor is constantly changing, so as to save the excitation current wasted by the motor due to load reduction to achieve the purpose of energy saving. At the same time, the power factor of the motor is improved. It is basically the same as the control elements used by the frequency converter, which are controlled by the characteristics of thyristors

in terms of application, the frequency converter may not be applied to some equipment because it changes the frequency of the motor, such as many equipment that cannot change the speed of the motor, such as escalators, belt conveyors, etc; Moreover, the frequency converter needs to change the equipment in many applications

powerboss is controlled by a closed-loop feedback system, and its induction circuit compares the voltage and current waveforms passing through the motor. Due to the induction circuit, there is a time difference between the voltage and current waveforms. The lighter the load, the greater the lag of the current waveform. The efficiency of the motor is the lowest at no-load, and the greater the gap between waveforms. The microprocessor will monitor the interval between waveforms and adjust the trigger pulse of thyristor accordingly, and its speed will change 100 times per second. This speed is much faster than the response speed of the motor, but it is very necessary to prevent the motor from stalling under any load condition

in principle, under light load conditions, if the excess excitation current can be reduced to match only the constant torque of the load, the operation efficiency of the motor can be improved

powerboss realizes control by changing the phase angle of the motor. In the figure below, voltage V and current I are expressed in phasor form, and the included angle between them is the phase angle. It can be determined as the amount of current leading or lagging voltage. For induction motors, the current usually lags behind the voltage, and the power factor (QPF) is a quantitative triangular relationship of current voltage lag

description of the relationship between motor power factor and phase angle

under different load conditions, the phase angle will change accordingly. The following figure is the description of motor voltage and current under different load conditions. Please note that under partial load conditions, the time lag between phase angle or voltage and current will increase. Generally, under load, the current of the motor lags behind the voltage by 30 °; Under no-load condition, the motor current lags behind the voltage by 80 °

powerboss continuously detects the phase angle between motor voltage and current, and changes the phase angle according to the change of load. POWERBOSS controls the voltage by using semiconductor switching elements such as three terminal bidirectional thyristors

the three terminal bidirectional thyristor only allows a part of the positive and negative half cycles of the power supply voltage to supply voltage, as shown in the figure below: such a result is to reduce the root mean square voltage supplied to the motor, minimize the hysteresis loss, return the phase angle to the original size, and improve the motor efficiency by further technological innovation. In order to better understand why the loss will be minimized, we must first analyze what factors will affect when the motor load changes

(III) differences in working characteristics between POWERBOSS and frequency converter:

frequency converter passed the inspection