The difference of series inverter and parallel inverter is that they use different oscillation circuits. The series inverter connects L, R and c in series and parallel inverter connects L, R and c in parallel.
Series Inverter vs. Parallel Inverter
The load circuit of series inverter has low impedance. The voltage source power supply is required and the large filter capacitor shall be connected at the DC power terminal in parallel. If the inverter fails, it is difficult to provide protection because of large surge current. The load circuit of parallel inverter shows high impedance and the current source power supply is required. The large reactor shall be connected at the DC power terminal in series. If the inverter fails, it is easy to provide protection because the large inductor can limit the current so as to avoid large impact.
Inverter refers to a device that converts DC power (such as storage battery) into AC power (usually 220V, 50Hz sine wave). Grid tie inverters are generally used in the system of large-scale solar photovoltaic power stations. Many parallel photovoltaic strings are connected to the DC input of the same centralized inverter. The off grid inverter can work independently after leaving the grid, which is equivalent to forming an independent small grid. This article will introduce on grid inverters and off grid inverters, discuss the working principles of off grid inverters and on grid inverters, as well as their differences.
Inverter is commonly used in the industrial field and its main function is to convert the current in a certain way. Transformer is a device that can change the AC voltage based on the electromagnetic induction principle. It is mainly composed of primary coil, secondary coil and iron core (magnetic core). To make it easier to understand the inverter, hereby the difference between inverter and transformer will be discussed.
Inverter is a device that can convert DC (direct current, such as storage battery) into AC (alternating current/mains), which is widely used in air conditioners, computers, lighting and other electrical appliances. Especially on traveling or working, inverter can generate alternating current by being connected with batteries, so as to supply power for the instruments or electrical appliances requiring alternating current for use.
It is very easy to change alternating current (AC) into direct current (DC), and with only a diode, the simplest rectifier circuit can be formed. However, it is not that simple to change direct current to alternating current. The magnitude and direction of alternating current will change periodically over time. The mains power we use shows regular changes of sine function.
Generator is an electromechanical device that generates electricity by transforming mechanical energy into electric energy. It generates electricity based on the electricity and magnetism work rules. It is driven by the wind turbine and hydraulic turbine of the system. The electricity generated by the system is for power station application and industrial application as main AC power.
Inverter is a power electric device that can convert one current into another current. This device is mainly used to transform DC into AC. The inverter takes AC directly from AC source and converts it into the DC by rectifier. The converted DC is used to charge the battery. At the same time, as AC is used in the industrial and household system, the DC from the battery will be converted into AC by the inverter. This system can be used to supply power for household electricity system in case of power failure. The inverter does not need external power to support its work. Although both the inverter and generator can improve the work efficiency, their functions are totally different.
In the solar off-grid system, the photovoltaic controller is to store the electricity generated by the photovoltaic module in the storage battery after transformation. In addition, it also has the functions of protecting the storage battery and preventing the battery from overcharging. At present, there are two main technical routes of the solar charge controller: Maximum power point tracking (MPPT) and pulse width modulation (PWM), both of which have its advantages and disadvantages, so users can select according to different scenarios.
Central inverter: The power is between 100kW and 2500kW. With the development of power electronics technology, the string inverter is having an increasingly bigger market, and the central inverters below 500KW have already basically been eliminated from the market. The power device adopts high-current IGBT. The system topology adopts DC-AC first-level power electronic device to transform the full-bridge inverter. The latter stage is generally connected to the double-split power-frequency boost isolation transformer. The protection level is generally IP20. It has a large size and is vertically installed indoor.
Pure sine wave inverters output the true sine wave AC power which is the same as or even better than the power grid we use every day since there is no electromagnetic pollution. Pure sine wave inverters, with high efficiency, stable sine wave output and high frequency technology, are suitable for all kinds of loads, which can not only power any common electrical equipment (including phone, heater, etc.), but also run the sensitive electronics or appliances (like microwave, fridge, etc.).