Hybrid solar inverter: types, overview of the best models + connection features

Benefits of Inverter Batteries

Modern homes are often subject to power surges and power outages. The heating system suffers the most from this, since in most houses water is heated using electricity. The presence of constant electricity affects the smooth operation of the gas boiler. Circulating pump and control automation.

If the heating boiler stops, it is likely that the pipes through which water passes will break, which will lead to the destruction of finishing materials and the appearance of cracks in the building structure. Inverter batteries have gained wide popularity in recent years and began to displace individual generators.Inverters work thanks to the fact that special batteries supply it with a power source.

Advantages of the inverter:

Sound and quick turn on. The inverter starts up silently: no one even notices how the battery power of the inverters starts up.

Noiseless at work. If the fuel-fired generators are very noisy, then the inverter makes no noise at all.

No exhaust

When using generators, it is important to think carefully about the location and exit of the pipes through which the gases leave the room. The inverter does not emit exhaust gases

fire safety

The inverter does not require fuel, which reduces the risk of fire.

Mobility. The inverter can be located in any convenient place.

When placing the inverter, it is important to pay attention to the fact that the room must have high-quality thermal insulation. The use of inverters is not only efficient, but also profitable. Of course, its purchase and installation will cost money, but in the future, inverters will pay off and save a lot of money.

Of course, its purchase and installation will cost money, but in the future, inverters will pay off and save a lot of money.

Of course, its purchase and installation will cost money, but in the future, inverters will pay off and save a lot of money.

How to calculate inverter power

The power of this equipment depends on the nominal power of the solar panels (on the DC side) and the maximum load power on the AC side.

In other words, you need to take into account the total power of all solar panels (permissible error from 90% to 120%) in the network and the power of all devices that can be simultaneously powered in this network.

If everything is clear with the panels, their rated power is indicated in the characteristics, then it is more and more difficult with consumption. It is necessary to determine the consumed peak or starting power of devices, which can be 5-7 times more than the working one.

Even a short load during start-up of 2-3 seconds, exceeding the power of the inverter, will not allow such a device to be started through it.

Choose by voltage

Such a parameter as the input voltage is also important, since it directly affects the efficiency of the system. Recommended parameters:

• 12 V for system power up to 600 W,
• 24 V with system power from 600 to 1500 W,
• 48V with system power over 1500W.

Choose by efficiency

This indicator is determined by the amount of energy that the device wasted, for example, for its work. The power consumption of the inverter itself should not exceed 5-10% of the energy passing through it. Otherwise, this device can be considered ineffective.

Most modern inverters have an efficiency of 90-95%.

Equipment weight

A quality inverter cannot be light as it uses a transformer. Conventionally, you can take the following figures: 1 kilogram per 100 watts.

Square wave and sinusoidal, signal type

Left - sinusoidal system, right - meander.

Meander, a cheaper option, however, such devices do not protect the network from voltage surges and allow for sudden surges, which can adversely affect the operation of household appliances and a lot of equipment. This problem can be solved by installing an additional stabilizer.

sinusoidal more expensive, but the voltage at the input and output is almost the same, and the fluctuations are smoother and do not harm the equipment.

A sinusoidal inverter is suitable for a private house, since all inductive loads (refrigerators, washing machines, pumps, air conditioners, etc.) simply will not work with a square wave output voltage.

Quasi-sinusoid - this is a kind of compromise between a rectangular shape and a pure sine. Most sinusoidal models are good, but there are also unreliable examples.

1 or 3 phase

Everything is simple here, any of them is suitable for a private house. Even if you do not need 3 phases, you will use one. For industry, only 3-phase is needed, since most equipment works on this principle.

What else to consider

• Input U, namely: voltage and power indicators must be optimally matched to each other. This will help avoid serious current leaks. Therefore, it will ensure the measured and productive operation of the inverter, without a dangerous “limit of possibilities”. Experts have long had such a concept as "a link between power and voltage." Recommended types of such bundles: 12 V and 600 W, 24 V and from 600 to 1500 W. If U is 48 V, the power may be more than 1500 watts.
• Output power, ideally calculated on the basis of the total summed up by all energy consumers. In reality, the calculations are carried out based on the maximum load that can be in the power grid. When operating a large number of household units, the level of inrush current can become much higher than the nominal capacity of the inverter. Therefore, you should focus on peak power indicators.
• Types of protection.If the inverter is of high quality, it is always equipped with more than one protection circuit. For example, cooling in case of overheating, protection against U surges and short circuits. Also, a good converter always provides for a protective circuit against overloads that may occur at the output.
• The operating temperature of the inverter is especially important if it is installed in an unheated room. If the range of temperature indicators is wide, then the converter is of good quality.
• Weight. If it is large, it is very good, because a quality transformer cannot weigh too little. There are low-grade converters for solar batteries. There is no transformer in them, therefore, as soon as the starting current becomes higher, the entire system can instantly stop working.
• The concept of standby mode. The standby mode saves a lot of energy in the battery, and power consumption is carried out only if it is necessary to maintain system performance.
• Inverter efficiency. You should choose high-quality models with an indicator of at least 90 percent. If the efficiency is less, the loss of energy supplied to the solar system from the Sun will be one tenth, which is unacceptable.

Modern features

In addition to the basic functions, hybrid inverters can perform a number of additional features.

Let's highlight the main ones:

• Mixing battery energy to power from a household network with priority selection.
• Regulation of the frequency of the current at the output, taking into account the voltage of the battery.
• Connecting a photovoltaic inverter to the network at the output.
• Adding power to an existing network parameter.
• Automatic transfer of power from the battery to the external network, taking into account the voltage on the DC source.
• Combined interaction with a network converter.
• Automatic addition of inverter power.
• Selection of the most attractive current source.
• Support for different types of batteries.
• Battery charging time regulation.
• Setting the voltage parameter.
• Software update, etc. Many modern models can be connected to a computer for monitoring and programming.

Note that the presence of additional options affects the cost of the product.

What else to consider

• Input U, namely: voltage and power indicators must be optimally matched to each other. This will help avoid serious current leaks. Therefore, it will ensure the measured and productive operation of the inverter, without a dangerous “limit of possibilities”. Experts have long had such a concept as "a link between power and voltage." Recommended types of such bundles: 12 V and 600 W, 24 V and from 600 to 1500 W. If U is 48 V, the power may be more than 1500 watts.
• Output power, ideally calculated on the basis of the total summed up by all energy consumers. In reality, the calculations are carried out based on the maximum load that can be in the power grid. When operating a large number of household units, the level of inrush current can become much higher than the nominal capacity of the inverter. Therefore, you should focus on peak power indicators.
• Types of protection. If the inverter is of high quality, it is always equipped with more than one protection circuit. For example, cooling in case of overheating, protection against U surges and short circuits.Also, a good converter always provides for a protective circuit against overloads that may occur at the output.
• The operating temperature of the inverter is especially important if it is installed in an unheated room. If the range of temperature indicators is wide, then the converter is of good quality.
• Weight. If it is large, it is very good, because a quality transformer cannot weigh too little. There are low-grade converters for solar batteries. There is no transformer in them, therefore, as soon as the starting current becomes higher, the entire system can instantly stop working.
• The concept of standby mode. The standby mode saves a lot of energy in the battery, and power consumption is carried out only if it is necessary to maintain system performance.
• Inverter efficiency. You should choose high-quality models with an indicator of at least 90 percent. If the efficiency is less, the loss of energy supplied to the solar system from the Sun will be one tenth, which is unacceptable.

The difference between an inverter and a BBP

When designing a hybrid power supply system, it is necessary to take into account the potential of the main inverter to provide electricity to the connected load. Quite often, these devices are called uninterruptible power supplies (UPS). However, despite the whole list of identical functions and tasks, these are essentially two different devices that are noticeably different from each other.

The fact is that the BBP is an inverter, in which a charger is additionally built in. This module is designed to prioritize the consumption of electricity generated by photocells, and only when it is insufficient, it switches to network consumption. The BBP does not have a circuit that allows the sharing of battery power and electricity from the central network. They are designed for separate consumption and switch between themselves when certain conditions occur.

Such operation in the mode of constant switching increases the number of charge and discharge cycles of the battery, causing its premature wear. Cheap uninterruptible power supplies do not have the ability to adjust the threshold voltage values.

In hybrid inverters used together with solar panels, there are no all the listed disadvantages that are typical for UPS. These devices independently adjust to the required power and can simultaneously operate with different types of power sources. Regulations provide for the choice of priority consumption and in most cases this role is assigned to solar panels. Some hybrid models are capable of limiting the power coming from the central grid.

TOP 1: MAP HYBRID 243X3

Characteristics

• Number of phases - 3;
• Maximum power - 9 kW;
• Peak value - 15 kW;
• Recommended total power - 100 W;
• Frequency - 50 Hz;
• Working temperature - minus 25 - plus 50;
• Size - 630x370x510mm;
• Weight - 61.5 kg.

Compatibility

The model of a three-phase hybrid inverter is compatible with electric solar stations and a household network, which is distinguished by an enviable efficiency value.In the absence of voltage in one of the phases, the remaining two will continue to broadcast it to the network, and the generation will be carried out by the battery.

Inverters, when changing the frequency, maintain communication with each other and with the generator, and can smoothly adjust to the frequency available.

Important: the duration of operation when the peak power value is reached is 5 seconds, and the value exceeding the nominal value (autonomous mode) is 20 minutes

Price

What is a hybrid inverter

Recently, there has been confusion over the definition of this concept, as many manufacturers call their inverters hybrid, although in fact they are not.

The inverter may include a controller for charging batteries from a DC source - solar panels or wind turbines. Very often, such inverters of the manufacturer are also called "hybrid". The reason for this is the fact that this inverter combines 2 different devices - an inverter and a controller for solar panels or a wind generator. However, such devices are better called "combined" rather than hybrid.

A feature of the hybrid inverter is precisely the possibility of parallel operation with an alternating current source - a network or a generator - in inverter mode. The hybrid inverter can use the power from the batteries charged by the renewable energy source at the same time as the power from the grid/generator without being disconnected from the grid.At the same time, it should be possible to set priority for a source of direct or alternating current; for example, when prioritizing a DC source, the load is powered first from the batteries, and the missing power is taken from the AC source. It is often possible to limit the current or power that is taken from mains or generator.

Priority for the DC source is possible only by completely disconnecting the mains from the input and switching to operation completely from batteries. This leads to "twitchy" operation of the system and additional cycling of the batteries. Well, if it is possible to choose the voltage at which the network is turned off and connected. But in many low-cost BBPs, this is not possible, and the threshold voltages are rigidly set without the possibility of regulation.

Some hybrid inverters have the function of adding the inverter power to the AC source power. This feature is very useful when the AC source has a limited capacity that is not sufficient to power the peak load. In this case, the maximum current is set in the UPS, which can be taken from the network or generator, and the missing power is taken from the batteries and mixed into the network. In this way, it is possible to feed the load with a power equal to the sum of the powers of the inverter and the AC source (grid or generator). Different manufacturers call this function differently - for example, it is called Smart Boost in Studer Xtender inverters, Power Shaving in Schnieder Electric Conext XW inverters, Grid support in Outback G(V)FX inverters, etc.

Comparison of an uninterruptible power supply and a hybrid installation

Some companies inadvertently mislead the consumer by referring to the uninterruptible power supply unit (UPS) as a hybrid inverter. It would seem that both devices perform similar tasks, but there is a significant difference.

The BBP is an inverter with a charger. The module primarily ensures the consumption of energy from the photovoltaic installation, and in case of its lack, it switches to consumption from the network.

The BBP is not capable of performing the function of "mixing" the accumulated electricity from the batteries with the mains. Priority consumption from a DC source is implemented by disconnecting from the network and switching to battery operation

The operation of the system in a "twitchy" mode provokes additional cycling of the battery and accelerates its wear. In most inexpensive UPSs, the threshold voltage is set to non-adjustable.

In models of hybrid inverters for solar panels, such jumps are excluded - the unit adjusts to the required power and works simultaneously with different current sources.

You can choose your priority consumption. As a rule, the emphasis is on the consumption of energy from solar panels. Some hybrid units have the option to limit the power coming from the city network.

Comparison of functions of popular modifications of hybrid "converters" and BBP. The Victron series of models provides the possibility of increasing the inverter power by using the mains

Hybrid Solar Inverter: Disadvantages

An alternative to receiving energy from the sun and converting it into electricity are solar power plants. The system can convert solar energy into alternating current only if there is a high-quality inverter. Hybrid inverters combine two types of inverters: networked and stand-alone.

The biggest plus is that the hybrid inverter can use direct and alternating current for its work.

It is important to note that the amount of sunlight and energy that is converted does not increase. But the inverter works many times safer

Disadvantages of hybrid inverter:

• Impossibility of functioning without mains voltage.
• The energy converter is powered by a battery, and if it is discharged, the inverter will stop working.

It is possible to solve this problem. To do this, just in case, you must always have additional elements that will work through the controller. Using a hybrid inverter is a great option for economical and intelligent use of solar energy. The cost of buying an inverter and installing it quickly pays off.

Types and features

Hybrid inverters conditionally differ in several criteria - the shape of the signal and the number of phases. Let's take a closer look at the features of each direction.

output waveform

There are three types of inverter according to the waveform:

Pure sine wave. At the output, an almost ideal curve is produced, which differs little from the shape of the sinusoid of a conventional network. This is the best solution when you need to power expensive equipment, such as compressors, boilers, electric motors and more.

Quasi-sine. Here, the output curve is not ideal, which can adversely affect the operation of some devices.As a rule, noise and interference appear, which in difficult cases lead to equipment failure. If motors (synchronous or asynchronous) are fed through a hybrid inverter, the power is reduced by about a third, and there are signs of overheating.

Quasi-sine devices are small in size and affordable. They are recommended for appliances that do not have inductive loads, such as incandescent lamps, heaters, etc. When buying, you need to look at the harmonic coefficient, which should be less than eight percent.

As for the last form (meander), it is almost never used. Its disadvantage is a sharp change in polarity, which may cause malfunctions and equipment damage.

By number of phases

The next criterion for hybrid inverters is the number of phases.

There are two options available here:

Single-phase. The output is 210-240 V. Used for a household network. Frequency - from 47 to 55 Hz, power from 0.3 to 5 kW. Available for batteries with a voltage of 12, 24 and 48 V

For proper operation, it is important to match the power of the device and the voltage of the solar battery.
Three-phase. They are used to power electric 3-phase motors in workshops, industry

They have power from 3 to 30 kW. Voltage - 220 or 400 V.

If desired, you can buy a combined version. A feature of the model is the ability to power a single- or three-phase load due to phase shift.