Device type
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Autonomous inverter. Voltage and power converters that are not connected to an external electrical network. They are supposed to be used as part of autonomous photovoltaic systems - such inverters generate electricity, which is spent exclusively for the needs of the household. It can be consumed directly by household appliances or accumulated in batteries. This type of inverter is often called off grid.
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Network inverter. Inverters operating synchronously with the external power supply network. They are designed to convert solar energy into alternating power with the parameters of the general network. Grid-connected inverters are used in battery-free systems - all generated energy is used for own consumption, and the excess is transferred to the network at a “feed-in tariff”. To do this, some indicators of generated electricity are adjusted, in particular, amplitude differences are eliminated, the network frequency is equalized, etc. Grid-tied inverters are also known as on-grid inverters.
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Hybrid inverter. Battery-grid inverters are peculiar hybrids of autonomous and network converters. Actually, this is where the name hybrid comes from. Inverters of this type work with battery chains, and excess electricity is sent to the general network. This ensures the energy independence of the system based on solar panels with the ability to use the energy a
...ccumulated in the batteries without disconnecting from the network. For example, if DC power is prioritized, power is primarily supplied from batteries, and any energy shortages are supplied from the external grid. This comes in handy in case of bad weather conditions or insufficient power generated by solar panels. If electricity is generated in excess, the excess energy is released into the general network at a “feed-in tariff”.
— Inverter for campers (motorhomes). Such narrow-niche inverters usually work in conjunction with a branded charging station - while staying at a campsite, it charges the vehicle’s battery. And while driving, such inverters are connected to the car’s alternating power generator and with their help, the energy reserves in the battery cells of the charging station are replenished.Output waveform
The form that the graph of the voltage produced by the inverter has.
This can be
a pure sinusoid with a high quality output signal - the voltage on the graph changes evenly, without sudden jumps and drops. It is as close as possible to the parameters of conventional sockets. Models with pure sine wave voltage allow you to connect almost any load - even delicate electronics that are sensitive to power quality. On the other hand, such quality requires the use of complex control circuits and significantly affects the cost of the inverter, and there is not always a real need for it.
Another option for the output signal shape is a modified (approximated) sine wave. As a rule, such graphs are constructed from stepped lines, sometimes quite large. The disadvantage of the modified sine is the inability to work with sensitive equipment (for example, where asynchronous motors or transformers are installed). However, in the absence of such a need, this moment cannot be called critical.
Maximum charge current
The maximum amount of direct current in amperes that the inverter can convert. If the solar panel produces a current exceeding this value, the inverter simply does not use it. This is often justified when connecting an inverter to high-power solar panels - the maximum input current of the inverter is reduced to acceptable values so that moderate-sized wires can be used to transmit energy.
Functions
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UPS function. Inverters with a UPS function automatically switch to battery-powered mode when there is insufficient power generation from solar panels or in cases where the main power source is disconnected. This ensures load redundancy. Note that switching may not occur instantly, but with a certain delay (about 10-30 ms).
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Connecting the generator. Inverters that support the generator connection function significantly increase the reliability and efficiency of autonomous solar energy systems. In practice, the function can be implemented in several basic ways. First, the system can automatically turn the generator on and off depending on the battery charge level or current power consumption, ensuring efficient use of resources and minimizing fuel consumption. Secondly, switching the load to the generator can be carried out when there is a shortage of electricity generation from solar panels. And thirdly, the generator can be used to maintain an optimal battery charge level so that the system is in full readiness at any time.
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Parallel connection. The inverter has special connectors through which two or more devices can be connected to a single electrical network. Parallel connection is used when one inverter is not able to pull the entire load from solar panels and the input power exceeds the capabilities of the device itself.
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Built-in monitoring. The presence of a built-in monitoring module on board the inverter, which collects information about the productivity of solar panels, allows you to monitor energy production and consumption, as well as monitor the performance of the system as a whole. Moreover, these parameters can often be viewed and controlled in real time (including through a mobile application for a smartphone). The monitoring module is usually connected to the Internet via a Wi-Fi network.
Control interfaces
Connection interfaces provided in the inverter design for solar panels.
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RS232. A specialized communication interface used to directly connect the inverter to a computer. As a rule, the interface provides the ability to monitor solar generation systems around the clock using a local network. Also, the RS232 connector can be used to communicate several inverters with each other, or, less often, for software updates or service testing.
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RS485. A connector often used to connect several inverters to a central hub, which, in turn, connects to a computer. This connection can be useful for setting up a solar generation system or sending monitoring data over the network.
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USB. A standard USB port is often used for configuring equipment via a wired connection to a computer or for inverter firmware updates.
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LAN (RJ45). The presence of a LAN connector (RJ45) in the inverter design. Such ports are standardly used for wired connections in computer networks using a twisted pair cable.
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Wi-Fi. Wi-Fi communication module for wireless connection of the inverter to a computer, laptop or mobile phone. Using specialized software, you can receive monitoring data from the inverter directly “over the air” - transmitting information over a Wi-Fi network eliminates the
...fuss with wires.
— Bluetooth. Option to wirelessly pair the inverter with smartphones, tablets or laptops via Bluetooth. Thanks to data synchronization, the user will be able to monitor equipment performance and remotely control the inverter within range of the Bluetooth wireless network.