While providing convenience to production and daily life, electrical energy also brings power quality problems. The amplitude, frequency and waveform distortion of power supply are all power quality related factors. Amplitude, frequency are controlled mainly by the power plant, while distortion of current or voltage waveform are mainly caused by electrical equipment and load. The harmonics of public grid is especially affected by electrical equipment.
With the rapid development of industrialization and automation, nonlinear devices and impact loads in use increased a lot. Power electronic devices such as switching power supply (computer, office automation equipment, home appliances...), motor speed control equipment (frequency converter), uninterruptible power supply, rectifier equipment (electric locomotive, electrolysis, electroplating...), arc heating equipment (electric arc furnace,...), lighting control system, etc. are applied in many occasions. Nonlinear electrical equipment are widely used in industries such as metallurgy, petrochemical, automobile, shipbuilding, machinery manufacturing, paper making, tobacco, electric railway, subway, tram etc., and in people’s daily life as electrical applicants. Excessive use of nonlinear equipment and impact loads causes voltage quality decline and the harm of harmonics.
And on the other hand, the automation and intellectualization of production process, the wide application of computer system and automatic control system are all making higher requirements for electric energy quality. For example, in harmonic interference sensitive industries such as radio and television, telecommunications, postal services, aviation, shipping, IT manufacturing, intelligent building, etc. and industries with massive usage of computer system or automatic system such as banking, securities, airport and other fields, all have increasingly higher demand for power quality and reliability.
Higher requirements on the quality and reliability of the power supply are associated with the technical development in production process. Progress in science and technology has promoted the automation and intellectualization of the production process, while making higher requirements for power quality. Resolving power quality problems can bring considerable economic benefits to power users and power supply enterprises, reduce operation cost of power system and line loss, decrease investment on devices, and even bring huge social benefits by improving the stability of power system to meet end users’ need for power supply with high quality and reliability.
Reactive power compensation:
AC power system requires two parts of energy: one part is active power that will be consumed, and transformed to thermal energy, solar energy, mechanical energy, chemical energy etc.; the other part will be used to create a magnetic field and to exchange energy, rather than act on external circuits, thus called reactive power.
All inductive loads, such as motor, transformer, and inductance need reactive power.
If reactive power cannot be supplied on site, it needs to be supplied by the power supply network of a higher level. Therefore, when designing the transmission capability of power system, both active power and reactive power need to be considered, resulting in transmission line and transformer of large capacity. Moreover, the transmission of reactive power will leads to increased number of lines and greater transformer loss, thus reducing economic benefit.
In enterprises, many electrical loads are inductive loads, with relatively low natural power factor. If reactive compensation measure is not taken, higher reactive loss will be produced, thus reducing the economic profits of enterprises.
To conduct Fourier series decomposition for non-sinusoidal wave, frequency component same to 50Hz of power frequency is called fundamental frequency, component with frequency greater than fundamental frequency is called harmonic. If harmonic current is injected into the power system, there will be pollution to power system, causing abnormal performance of distribution system and even equipment failure. Harmonic not only threatens the safety of the power system, but also harms power users:
● Generate additional loss to equipment in power grid, reduce the efficiency of the equipment;
● Affect the normal operation of equipment, increase the vibration and noise of equipment;
● Accelerate the aging of insulating medium of capacitors, cables and other equipment, reduce service life of the equipment;
● Easy to cause resonance, give rise to harmonic amplification, thus producing overcurrent and overvoltage, resulting in equipment damage;
● Disturb the operation of electronic equipment, automation equipment, computer, and communication equipment, cause equipment malfunction
Smart grid provides safe, reliable, clean and economically affordable electricity. Electrical equipments are becoming more and more sensitive to energy quality. Poor energy quality can cause serious damage to industrial production, people's life and social economic development. In this sense, providing power quality that can meet the need of users of the 21st century should be an important feature of smart grid.
The smart grid will reduce power quality problems from power transmission and distribution system. Monitoring the basic elements of the grid by advanced control methods helps to quickly diagnose and accurately come up with solutions to any power quality problem. When designing smart grid, considerations should be given to reduce power quality disturbances caused by lightning, switching inrush current, line fault and harmonic sources, and to solve power quality problems by latest power and electronic technologies on improving power quality. Smart grid will adopt technology and management means to save the grid from adverse effects on the power quality caused by load user, astrict load user generated harmonic currents from injecting into the power grid by monitoring and executing related standard, use proper filtering compensation device, prevent the harmonic pollution from being sent into the power grid to deteriorate power quality.
Energy Efficiency Management:
To improve energy efficiency means to provide the same service with less energy input. As a developing country, China has become the second largest energy consuming country in the world. However, due to low energy efficiency, shortage of energy supply, excessive reliance on coal, the thus caused environmental pollution is a challenge that China has to face in the future.
In order to realize rapid economic growth, we cannot rely only on increasing energy production and supply to meet domestic demand. We need to maintain economic growth on the one hand, and protect the environment on the other hand. Therefore, China must find ways to save energy, improve energy efficiency. Improving energy efficiency means to realize relatively high economic growth with relatively low energy consumption.
As competition in traditional industry becomes more and more intense, a majority of enterprises are facing declining profits, which can only be solved in two ways: enhancing market development and strengthening cost control. Comparatively speaking, cost control is easier to implement, and of lower risk. And among the costs of industrial enterprises, electricity cost accounts for the third or fourth largest cost, following material costs, labor costs. This is particularly true in some high energy consuming enterprises, whose main cost is electricity. Energy efficiency management helps enterprises to reduce investment in energy and to increase the competitiveness of their products, promotes local economy, and allocates resources in a more economical and equitable way, alleviates the pressure on the environment, and plays an important role in maintaining sustainable development.
Dynamic reactive products of our company:
1) ADTBBH hybrid active power filter
2) ADTBB LV automatic reactive power compensation device
3) ADTBB outdoor LV reactive power compensation device
4) ADTBB HV reactive power automatic compensation device
5) ADTBB HV line reactive power compensation device
6) ADFC HV filter compensation device
Energy Saving Transformer:
Due to the high permeability, amorphous alloy transformer has low no-load loss and load loss, which makes it energy efficient. On November 6, 2012, the Ministry of Finance, the National Development and Reform Commission, the Ministry of Industry and Information Technology of China jointly issued the “Implementation Measures of Energy Efficient Product People-benefit Project – promotion of energy efficient distribution transformer”. China starts to promote energy efficient transformer at national level.