Along with the development of the industry of power quality, the low voltage reactive power compensation in China is in rapid development period, compared with high voltage reactive power compensation, the low voltage reactive power compensation device close to the load side, conforms to the principle of "local governance", its benefit in reducing line loss significantly higher than that of high side compensation; In order to improve the power quality, dynamic real-time response can be achieved, and the voltage quality of power supply can be guaranteed effectively. In the low pressure side, the installation cost of equipment and the cost of operation and maintenance will be greatly reduced. Therefore, reactive compensation is the best compensation method for reactive power compensation. Low-voltage side reactive power compensation is really only about a decade or so in China. Now we are going to review several stages of the development of low-voltage reactive power compensation.
Stage 1: the era of pure capacitor compensation (before 2004)
Before 2004, the domestic reactive compensation in the industry is on the high side for reactive power compensation, and compensation in low voltage side or not do, or use a separate capacitors for reactive power compensation. At that time, the capacitor products were made of domestic capacitors, which were usually traditional capacitors with oil or paraffin wax. Low voltage reactive power compensation at this stage have not been enough attention, until around 2000, with the rapid development of power electronic technology, frequency conversion energy-saving technology is widely applied in all walks of life, the inverter in the application process produces a large number of harmonics injected into the power grid, resulting in a decline in the power quality of the power grid, the most direct performance is reactive compensation capacitor, began to appear a wide range of use of capacitor failure (oil, drum abdomen, explosion... ), the safety and stable operation of the power supply system brings huge hidden dangers.
Stage 2: the era of safety compensation (2004 - present)
Simple capacitor compensation under a harmonic environment operation, easy cause harmonic amplification and lead to power system fault, lead to low voltage reactive power compensation industry are faced with the problem, this time some foreign brands (nokia, du kai, inbev) began to gradually into the country, has brought the advanced products and advanced compensation ideas - security compensation (in capacitor front series reactor to form LC circuit, reactive power compensation), foreign products to enter also caused the capacitor quality of the product to the attention of a user, this period of competition in the market competition is mainly foreign brand products. The appearance of safety compensation concept guarantees the safe and stable operation of capacitor compensation in the environment with harmonics, and is also the mainstream compensation mode on the market.
Stage 3: energy-saving safety compensation (2013 -- present)
As security compensation concept is deeply rooted in the hearts of the people and the market competition intensifies, the low voltage reactive power compensation market development has entered the phase of bottleneck, this stage takes the lead in putting forward inbev electrical and energy-saving reactive compensation equipment, adopt new soft magnetic material instead of traditional silicon steel sheet production reactor, the reactor than the original loss was reduced by 50% or more, greatly reduce the wastage of the reactive power compensation device, so as to achieve the goal of energy saving
Stage 4: low voltage active compensation - low pressure SVG (2012 - present)
The popularity of active filter not only has brought the rapid development of harmonic governance, but also drive the reactive power compensation industry from the traditional passive compensation to the active compensation aspect development, developed on the basis of active filter technique of active low voltage reactive power compensation (low voltage SVG) has already started to run to the traditional reactive compensation in the industry, and obtained a good running effect, compared with the traditional passive compensation, compensation has quick response speed, active compensation of high precision, wide range of compensation (two-way compensation), safety (not with system to produce resonance), and other advantages, to say the low-pressure SVG represents the current reactive compensation the development of the industry's most advanced technology.