In the solar PV grid system, the solar module, inverter and power grid can constitute the electrical system. The component will convert the solar energy based on the solar radiation and then inverter will output related power. Thus, an on grid inverter does not have special demand on the AC overload because basically the inverter output power will not exceed component power. In the solar PV off-grid system, component, battery, inverter and load constitute the electrical system. The output power of the inverter is decided by the load. The start power of motor of some inductive-load devices like air conditioner or water pump is 3-5 times of the rated power. Thus, the off grid inverter has special requirements on the overload situation. In solar PV off grid system, the output power is determined by the load. When motor or other devices with inductive load are started, the large current will be required within short time. The PV system and battery are not able to provide this energy. In addition, if the lithium battery outputs excessively in short time, it may explore. However, the capacitor, inductor, transformer of the off grid inverter can store power and will not be damaged even if it amplifies the output for several times in a short time. Therefore, off grid inverters can be overloaded several times.
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.
There are 8 tips to consider when selecting the proper off grid solar inverter, let us see as following.
1. The off grid solar inverter output voltage and frequency. This will base on your load requirements and usually its same as your country standard supply voltage/frequency.
2. Installing off grid solar inverter or hybrid inverter. Most of off grid solar inverters and hybrid solar inverters have AC backup supply connection, so the inverter bypass to use it for feeding your loads in case of sun absence and batteries discharged. Moreover, you can use this AC backup supply to charge the batteries through internal solar inverter batteries charger.
In order to install photovoltaic solar system in your building, you need to choose in between 2 main solar system types: On Grid and Off Grid. Which one will be the most technically suitable and cost effective as well? As an one-top online shop, inverter.com provides full range of solar inverter products to customers worldwide. On grid inverters, off grid inverters, micro inverters could be found in our shop.
Off grid solar system is more complex in installation than on grid solar system, as it requires more components like charge controller and batteries, so it needs higher technical skills and costs more. Although of this, off grid solar system market grows and most of suppliers / manufacturers try to save the cost and complexity by searching and implements new techniques and services that you should pay attention for as following.
Off grid solar inverter converts DC electricity comes from solar panels and stored in Batteries to AC electricity to be used to run all of AC loads types existing now like TV, refrigerator, oven, lights, air conditions…etc. What are parameters to check when buying the off-grid inverter?
Invreter.com online store provides two kinds of off grid solar inverters: Multi-function inverter/ charger with rated power 700W to 6000W and three phase pure sine wave inverter with high power 8kW to 200kW. Cheak the price list as shown below and choose the right off grid inverter to meet your PV system.
The off-grid photovoltaic power generation system for household use consists of the photovoltaic module, supporter, controller, solar inverter, accumulator and power distribution system. The system's electric plan design should take the selection and computing of modules, inverters (controllers), and accumulators into consideration. Before the plan design, necessary preparation should be made, because the off-grid is customized without a unified plan. Therefore, the user load type and power, electricity consumption in the daytime and in the evening, and climate conditions of the installation place should be first learned. The power supply for the off-grid photovoltaic system relies on the weather, which is not 100% reliable.
In the photovoltaic off-grid system, the power parameter of the power inverter selecting is generally confirmed according to the load type and power of the user. The load is classified into the following types according to the impedance property: Resistive load, inductive load, and capacitive load. The load is classified into the following types according to the impedance property: Resistive load, inductive load, and capacitive load. The resistive load: The load with no phase difference between current and voltage is a resistive load, such as the electric cooker, bulb, electric furnace, electric soldering iron and so on.