Solar inverter

After installing solar panels on the roof or on trackerYou'll need one more important part: a solar panel inverter. It's what determines whether your home will have 220-volt power. This device converts direct current (DC) from 12-48 volts to alternating current (AC). This ensures that all your appliances receive the correct voltage.

Solar panel inverter and how to choose it?

This installation includes the following:

1. A low frequency adapter that contains many semiconductor diodes.
2. Varicap. This thing works using triodes. Their conductivity reaches 4 microns.
3. Dynistors. They are needed for sensitivity.
4. Linings.
5. Uninterruptible power supply module.

When, for some reason, the power supply from the regular grid is interrupted, current will flow to the batteries. From there, it will flow into the outlet, and electrical appliances will continue to operate.

The UPS uses a microcontroller to monitor voltage data. When power from the main grid is interrupted, this device sends a command to connect additional power sources.

Some inverters have a built-in transformer. This is good, as it delivers a high-quality signal. However, it's not as easy, as it increases weight. A fan is also included for cooling, but this will make the device very expensive.

If one inverter isn't enough, you can get three and combine them into a single three-phase module. This will result in a lot of power and 380 volts. 400 and 690 volt inverters are also available.

How does a solar inverter work?

First, solar light is converted into electricity using photovoltaic panels. Then, the battery is recharged. This is accomplished by adjusting the required voltage and current. To control these parameters, a system is used. voltage stabilizerand the controller. Then, a constant flow of directed particles from the batteries is transferred to the inverter for solar panels and is converted into alternating current. It then travels through a series of wires to the load.

The energy stored in the batteries is used at night or in cloudy weather—that is, when there is no power from the solar panels.

Choosing an inverter for solar panels

Parameters to pay attention to:

1. What protection does the device have?
2. How sensitive is it to radio interference?
3. What is the maximum voltage it can detect?
4. Efficiency should be from 90-99%.
5. Utility coefficient.
6. What is the power and current at the input and output?
7. It should produce a stable voltage at the output (a trapezoidal type is best). The input voltage should be minimal.
8. Losses should be small when there is no energy inflow.
9. Harmonics should be reduced.
10. The solar inverter must be protected from heating and overload.
11. What temperature ranges can it operate in? It's best if they're very wide.
12. How sensitive is it to household appliances?

Before purchasing, calculate the inverter's load. To calculate this, simply find the product of the inrush current and the voltage level in your grid. The solar module supplies 12 volts. The controller then activates, sending a signal to the inverter. This converts the voltage to 220 volts.

In addition to all of the above, make sure the device has ventilation and protection. Find out if the propeller speed can be adjusted and if it runs continuously. Good devices will shut off when there's no overload.

Each converter must have the following protection:

1. From overheating.
2. Castle at the exit.
3. Overloads.
4. Low and high U of the battery.

It should also consume 1% of power when idle.

Additionally, some devices of this type have a standby mode. This helps conserve battery power. It's advisable for this feature to have a manual shut-off option. Otherwise, it may cause problems with low-power household appliances.

Types of solar inverters

There are many varieties of these devices, and choosing the right one isn't easy.

Modified or grid-tied inverters

The production process is based on varicap diodes. They have a low-frequency modulator, which allows for variations. They are ideal for round solar panels. Most of them have a conductivity of over 40 microns. They have insulator pads. There are even some that operate through a charge controller.

Rectifiers for inverters have a frequency of about 30 Hz, and sometimes higher.

The grid-tie solar inverter has the following advantages:

• Small size.
• Good protection.
• Low energy consumption.
• Fast voltage conversion.

This type of inverter has the same capabilities as a grid-connected inverter. However, it can increase power during overloads, eliminates metering issues, and operates when the 220-volt grid is lost.

Sometimes the inverter housing has a controller built into it. Many sellers refer to this device as a hybrid. In reality, this is not the case; it is a combination device.

Hybrid inverter

It combines the features of all other devices of this type. This is the most expensive, but the most suitable solar inverter.

The hybrid device can additionally draw power from the grid and the battery. It prioritizes constant voltage. If for any reason the battery's current is low, it will draw power from the grid.

Inverters operating in autonomous mode

These are ideal for solar panels of various wattages. They operate even during surges of up to 4A. They support three circuits. They may be marked "OFF Grid." They do not contact the mains. Power ratings range from 100 to 8000 watts.

If you see a device labeled "On Grid," it has an additional function. It can monitor amplitude changes and frequency.

If the external network malfunctions, the autonomous inverter will switch off.

• On the multiple current side, the inverter is selected based on the nominal power of the solar panels.
• If the total power of the devices used in the home is less than the solar power plant's capacity, then the excess electricity produced goes into the external electrical grid.
• If the power is insufficient for normal operation of home devices, then power is supplied from outside.
• If there is no voltage, power is supplied from a charged battery. If the system does not have integrated batteries, the energy produced solar power plant, goes into a single network.
• Grid-tie photovoltaic inverters use the energy generated by solar panels with great efficiency.

Main advantages:

1. The price is within the normal range.
2. Quickly convert voltage.
3. They work stably at high humidity.
4. A reduced varicap is easy to install.
5. Frequency adjustment is available.
6. Electrical conductivity is reduced.

They generate a signal: 1) pseudo-sinusoidal; 2) rectangular; 3) sinusoidal. They may also be called meander waves. That is, they are not sinusoidal.

The first one has the following features

Something in between the other two signals. Its features:

• Low cost.
• All devices work perfectly.
• Generates noise waves, creates interference.
• Sensitive devices cannot operate in the presence of this signal.

Characteristics of the second

This type is best used to transmit voltage to lighting devices.

Peculiarities:

• They work simply and clearly.
• The cost is low.
• Not protected from power surges.
• They are not suitable for every household appliance. They may simply be incompatible.

Sine wave signal and its characteristics

They produce good current with the required sine wave. Ideal for large household appliances.

Key Features:

• Protects equipment from sudden voltage changes.
• They are expensive.

If there are 100 watts per kilogram, then it is equipped with a transformer.

What is the difference between grid-tied and stand-alone inverters?

Standalone units can operate without an additional battery. These devices only work with devices that can monitor power. When power is adequate, they automatically connect and generate electricity. They have built-in standard power outlets.

Mains chargers require devices that will charge the battery. They also have special devices to prevent confusion. polaritywhen connected. They control the battery charging.

If the power converter has a power output greater than 500 watts, a secure connection is required. A reliable connection is essential. A poor connection could result in a fire or spark.

How to connect a solar inverter?

Before doing this, you should familiarize yourself with some nuances.

1. Find out what frequency the signal is: sine, square or pseudo sine.
2. The installation wires should be of medium length. 3 m is ideal.
3. Depending on the power, you need to select the cable cross-section.
4. Check what shape the output signal is.
5. The use of uninterruptible power supplies allows switches to be integrated directly into the circuit.
6. The cable must be securely fastened to prevent short circuits and fires.
7. If the power station is far from the house, you'll need to extend the cable. Ideally, the inverter should be located near the battery.

As a result, everything is simple and anyone can start a solar panel inverter.

If the solar installation's power does not exceed 5 kW, then 1 inverter will be enough.

Solar panel inverter circuit diagram

 

A brief overview of well-known inverter brands

ChintPower Systems Co., Ltd.

This type of inverter is quite expensive. It's made in China. It produces a pure sine wave with reduced noise of approximately 30 decibels. It has a power rating of 1000 VA and a voltage rating of up to 230 volts. A solar panel with this inverter can produce up to 1200 watts of power. The price tag ranges around 40,000 rubles.

Inverter from Cyber ​​Power

Considered a budget-friendly microinverter for solar panels, it produces a pure sine wave signal. It's ideal for low-power devices and can perform automatic switching. Output power is 200 VA. Output voltage is 220 V. It transfers to the battery in 4 ms. It costs only about 5,000 rubles.

Voltronicpower

This company's device has a built-in charge controller. It also uses a pure sine wave. It has a maximum power of 1600 watts. The output voltage is 230 V and the output frequency is 50 Hz. Purchasing it will cost you around 20,000 rubles.

To obtain maximum output from the entire power plant, it is necessary that each component of the system be in harmony with each other.

MAP "Energy"

This company produces Russian-made inverters with power ratings ranging from 800 to 1200 watts.

The following converter variants come off its production line:

• 3-phase.
• Inverters generating pure sine wave.
• Devices that borrowed additional energy from the battery.

Each of these devices is capable of charging batteries. This type is widely used for both domestic and industrial purposes.

This company has released a device with a power output of up to 20 kW. It's their pride and joy! It can handle loads of up to 25 kW.

Schneider Electric

This company produces solar inverters with excellent performance characteristics. These units can be safely used in cloudy weather. The housing is coated with anti-corrosion protection, which allows it to withstand salt deposits.

The French company abandoned electrochemical capacitors in its production, giving it an advantage in the consumer market.

The efficiency of the devices produced by this company is 97.5%. Using an inverter from this company, it is quite possible to build a solar power station with a capacity of 3-20 kW.

TBS Electronics

The company has been manufacturing inverters since 1996. Their devices are compatible with Poversine solar modules with power ratings ranging from 175 to 3500 watts. The metal surface protects them from various harmful factors. High-quality electronics ensure reliable operation.

This type of device is protected against short circuits and overloads.

Kostal

Manufactures converters of various types and power ratings. Some units have a built-in AC switch. Many units are already integrated into this device.

Anyone can master this device. It's easy to install and very user-friendly. The manufacturer provides a full 5-year warranty. It's manufactured according to European GOST standards.

Taiwanese ABi-Solar inverters

These are SL/SLP standalone and hybrid vehicles. They have built-in controllers for recharging the battery. Taiwanese developers combined three devices in a single device: a controller, inverter, and charger.

The built-in screen allows you to monitor incoming data. Efficiency is 93%. Some similar devices are protected from various types of dust.

The ABi-Solar SL 1012 PWM model delivers 800 watts of power. It makes it easy to automate the charging process.

Manufacturer GoodWE

A Chinese manufacturer produces high-quality devices and sells them at a low price in Russia. Specialized software can be used to perform calculations, allowing you to extract maximum efficiency from your solar power station.

The operation of the installation can be controlled using a regular mobile phone.

Thus, by installing the right inverter for solar panels, you can become completely independent of the standard power supply.