Inverter Current research and development at home and abroad

Inverter, rectifier means flyback converter, its role is by opening a semiconductor power switching devices on and off action, the DC can be converted into an AC power of power electronic converters. Inverter applications will become increasingly important. The 21st century is energy development, resource utilization and environmental protection co-ordination century of development, optimize the use of energy and the development of clean energy is an important part of the energy resources and environmental strategies for sustainable development.
Oil, gas and coal and other fossil fuels, known as the world's three major energy will gradually be depleted, hydrogen and renewable energy will gradually replace fossil fuels and become the subject of energy for human use, the changes will force this energy generates electricity generation high efficiency and low fuel cell power generation a big change, the use of hydrogen and renewable energy, will become the main power generation. Therefore, the 5000w pure sine wave inverter technology in the field of development and utilization of new energy has a crucial position.
SPWM (Sinusoida-PWM) sinusoidal pulse width modulation sine wave modulation, the carrier is a triangular wave or a sawtooth pulse width modulation method, which is 1964 by A.Schonung and H. Stemmler the communication system modulation technique applied to the inverter generated, because of the slow speed of the switching device without timely promotion, until then equal to the Bristol University SRBowers 1975 SPWM technology only then formally applied to the inverter technology the performance of the inverter is greatly improved, and has been widely used and development, but also to sine wave inverter technology has reached a new height. Features of this technology is simple in principle, versatility, control and regulation performance, with the elimination of harmonics, regulate and stabilize the output voltage of a variety of roles, it is a good waveform Improvement Act. Since then, a variety of PWM techniques have emerged, such as third harmonic injection PWM, space vector modulation, current hysteresis PWM, etc., become the high-speed switching devices of the inverter dominant control. So far, the development of a 48v to 220v power inverter technology has been basically perfect.
In the sine wave inverter control method, at home and abroad there are more studies than PID control, deadbeat control, bicyclic feedback control, repetitive control, variable structure control, fuzzy control and neural network control. PID control is a conventional control method, because of its simple algorithm mature design process overly dependent on system parameters, robustness and high reliability, in simulated sine wave inverter control system has been widely used. With the development of microprocessor technology, with faster static and dynamic response characteristics of the digital PID algorithm also has been used.

Solar inverter maximum power point tracking control principle

Maximum power point tracking (maximum power point tracking,) control is the real-time detection of the Solar power inverters cell voltage and current output characteristics, the use of certain control strategies to detect the current operating conditions of the solar cell maximum possible power output by changing the impedance of the current situation The maximum power output to meet the requirements. Thus, even in poor lighting, solar output power is reduced or inadequate, the system can still run best under the current conditions.
Take advantage of the energy generated by photovoltaic cells is a basic requirement of photovoltaic power generation system to solve this problem can be added maximum power point tracking device between the photovoltaic cell and the load, so that the photovoltaic cell maximum output power has always been able to make more efficient use of solar energy.

Transformerless inverter use advantages of BIPV

Conventional inverter BIPV often limit the use of the photovoltaic inverter system design, for example, 1 MW system, using two 500KW inverter system need to install the inverter on the ground, for this reason traditional inverters relatively large size and weight, is not suitable for installation in roofs. If transformerless inverters, its small size and because of its light weight, can be directly connected with the solar panels on the roof.
A plurality of inverters may be connected in parallel without the use of a transformer, and power can be used directly, in order to achieve stable performance. Transformerless 300w solar inverter technology uses a much larger power optimizer (Line Reactor) and smaller triangles filter capacitor. These smaller triangles by means of a filter capacitor series resistors are buffered, and thus improve the stability of the control system, and to reduce the interaction between the parallel 3000w solar inverter . A design with a single engine 500 kilowatts inverter also reduces the number of parts, thereby improving overall system reliability.
Using multiple inverters do conventional photovoltaic systems, each must have a separate isolation transformer to match, resulting in reduced efficiency because there is energy loss isolation transformer. Without transformer type no isolation transformer, thus obtaining additional power from photovoltaic modules to supply energy to the load.
Without a transformer, DC AC power inverters smaller size, lighter weight for the power integrators to provide greater freedom in installation and overall system design. Because of weight restrictions and the need of reinforcement measures, five-storey building in the roof of the building to install a conventional inverter from a cost point might be prohibitive, but the designer was able to make a transformerless inverter is installed in commercial buildings on the roof (not installed in the basement), so that it is directly connected with the fifth floor of the mounting plate. This design not only can remove up to five floors of expensive DC wiring, but also shorten the length of the AC cord and reduce associated costs.