Photovoltaic Inverter

1.Brief introduction of the photovoltaic inverter
The photovoltaic inverter developed by Rongxin has independent intellectual property rights. Integrating advantages of similar products, our photovoltaic inverter has a cost performance ratio remarkably superior to like imported products. DSP controller chip of the US and high power IGBT modules are adopted to combine advanced MPPT technology, reactive power based on the instantaneous reactive power theory with harmonic current compensating control into an organic whole. By doing this, service efficiency of inverted power supply is enhanced and, at the same time of providing certain active power to the power system, inverted power supply can compensate reactive power and harmonic current.

2.Technical features
1) We have introduced Ansaldo technology of Italy in every respect, and our photovoltaic inverter is especially suitable for high power inversion cases.
2) The photovoltaic inverter is equipped with Motorola RISC CPU as its control CPU, and makes use of SPWM modulation with fuzzy control and optimized maximum power point tracking technology to guarantee its highly efficient output.
3) By independently developed dual current control technology, the photovoltaic inverter optimizes the quality of power transmitted to power grid maximally.
4) New intelligent vector control technology has enabled the photovoltaic inverter to prevent power system from being affected by three phase imbalance. Meanwhile, the photovoltaic inverter increases the utilization rate of direct voltage and widens the input range of direct voltage.
5) With internationally advanced IGBT, the photovoltaic inverter effectively reduces the switching loss and conduction loss, and enhances efficiency of system.
6) All-fiber driving technique has safely avoided false triggering of the system and enormously lessens electromagnetic interference to the system. Stability and reliability of the overall machine control are therefore greatly improved.
7) Voltage transforming power source of 50Hz is selected to achieve mutual isolation between photovoltaic arrays and power grid.
8) Our photovoltaic inverter is designed according to international standards, IEEE1547 and UL1741, for example. Besides, the photovoltaic inverter boasts advanced islanding detection scheme, complete defensive function and supervisory control. In addition, various communications systems are available, such as RS485, Ethernet, GPRS and so on.
9) Technical parameters of inverted power supply are specifically set in order to adjust to the large fluctuation of China’s power grids.
10) Optimum structure and circuit design help to decrease components of the system, thus lowering the cost and improving the efficiency of heat dissipation and stability of the system.
11) User–friendly human-computer interface, multilingual menus, comprehensive parameters and control function are available for users to have a timely command of the overall information of the system.
12) Circuit and control algorithm of the system are rigidly simulated and calculated by internationally authoritative simulation software, such as PSCAD, PSPICE, MATLAB, etc. All the parameters are repeatedly optimized and have undergone RTDS simulation verification. Besides, the whole set has been strictly tested in different environment (with varied temperature and humidity), and quadratically optimized in order to achieve best performance.
3.Application mode
1)Standard application mode
Photovoltaic cell and inverted power supply with equivalent power capacity are simply connected and controlled.

2)Parallel application mode
A disadvantage of the standard application mode is when photovoltaic cell is not working at its full power, all inverted power sources at the photovoltaic power station are at the operative status. As a result, the inverted power sources have very low working efficiency, and great power loss is thus induced. Comparatively, under the parallel mode, the photovoltaic cell transmits power through an inverted power source to the power grid when the other power sources are on standby. With the increase of output power by photovoltaic cell, inverted power source starts to work one after another.

4.Technical parameters