Inverter

FAQ about inverters

What is an inverter?

An inverter is an electronic device that converts direct current (DC) power to alternating current (AC) power. It typically takes a DC input from a power source such as a battery, solar panel, or a DC power supply, and produces AC output that can be used to power a wide range of electrical devices such as appliances, electronics, and machinery.

Inverters are commonly used in a variety of applications, including residential and commercial solar pv power systems, uninterruptible power supply (UPS) systems, automotive applications, and in recreational vehicles (RVs) and boats. They are also used in industrial settings where converting DC power from batteries or renewable energy sources to AC power is required for powering motors, pumps, and other electrical equipment.

Inverters work by using electronic components such as transistors and capacitors to switch the DC input voltage on and off rapidly, creating a waveform that resembles AC power. This AC waveform is then filtered and shaped to produce a stable AC output with a specific frequency and voltage level that is compatible with the electrical devices being powered.

Inverters come in various types and sizes, ranging from small portable inverters that can power a single device, to larger grid-tied inverters used in solar power systems that can feed excess power back into the utility grid. They may also include additional features such as built-in battery chargers, voltage regulation, and protection mechanisms to ensure safe and efficient operation.

Solar PV Power Inverter

A solar PV (photovoltaic) power inverter, also known as a solar inverter or PV inverter, is a type of inverter specifically designed for use in solar power systems. It is a critical component in grid-tied solar power systems, which convert sunlight into electricity using solar panels and then feed that electricity into the utility grid or use it for powering local loads.

Solar PV power inverters are responsible for converting the direct current (DC) electricity generated by the solar panels into alternating current (AC) electricity that is compatible with the electrical grid or can be used to power household or commercial appliances. Solar panels produce DC electricity when exposed to sunlight, and the solar PV inverter is responsible for converting this DC electricity into AC electricity that can be used by the electrical devices in a home or business, or fed back into the utility grid.

Solar PV power inverters typically include features such as maximum power point tracking (MPPT), which optimizes the solar panels’ performance to ensure they produce the maximum amount of electricity, and various protection mechanisms to safeguard against overvoltage, overcurrent, and other electrical issues. They also often have monitoring and communication capabilities, allowing for remote monitoring of the solar power system’s performance and integration with other components of the solar power system, such as battery storage systems or smart grid technologies.

There are several types of solar PV power inverters, including string inverters, microinverters, and power optimizers. String inverters are the most common type and are typically used in systems where multiple solar panels are connected in series to form a “string” and then connected to a single inverter. Microinverters, on the other hand, are installed on each individual solar panel, allowing for individual panel-level power conversion and monitoring. Power optimizers are similar to microinverters but are typically used in systems that combine string inverters with module-level power optimizers to optimize the performance of each panel in a string.

Solar PV power inverters play a crucial role in solar power systems, as they enable the conversion of solar energy into usable electricity for powering homes, businesses, and feeding excess electricity back into the grid, making solar power a viable and sustainable source of renewable energy.

Power Inverter

Power inverters are commonly used in various applications where AC power is required but only DC power is available, or when a change in voltage or frequency is needed. They can be used in a wide range of settings, including residential, commercial, automotive, and industrial applications.

Power inverters work by using electronic components such as transistors and capacitors to switch the DC input voltage on and off rapidly, creating an AC waveform that can be used to power electrical devices. The AC waveform produced by a power inverter can be modified to have different voltage levels, frequencies, and waveforms, depending on the specific requirements of the application.

Power inverters are available in different types and sizes, ranging from small portable inverters that can power a single device, to larger grid-tied inverters used in solar power systems, and high-power industrial inverters used in heavy machinery and industrial processes. They may also include additional features such as voltage regulation, surge protection, and various types of output waveforms (e.g., sine wave, modified sine wave, square wave) depending on the intended application.

Power inverters are used in a wide range of applications, including powering household appliances during power outages, providing AC power in remote locations, enabling the use of electronic devices in vehicles, converting renewable energy sources such as solar or wind power into usable AC power, and powering industrial equipment and machinery. They are an essential component in many systems that require the conversion of DC power to AC power for practical use.

Where an inverter is used?

Some common areas where inverters are used include:

1. Renewable Energy Systems: Inverters are used in solar power systems, wind power systems, and other renewable energy systems to convert DC power generated by solar panels, wind turbines, or other renewable energy sources into AC power that can be used to power homes, businesses, or fed back into the grid.
2. Uninterruptible Power Supply (UPS) Systems: Inverters are a key component in UPS systems, which provide backup power during power outages or other disruptions in the electrical grid. UPS systems are commonly used in data centers, telecommunications systems, critical medical equipment, and other applications where continuous power supply is essential.
3. Automotive and Marine Applications: Inverters are used in vehicles, such as cars, trucks, boats, and recreational vehicles (RVs), to convert DC power from the vehicle’s battery or other DC power sources into AC power to run various electrical devices, such as appliances, tools, and entertainment systems.
4. Off-Grid and Remote Power Systems: Inverters are used in off-grid or remote power systems, where access to the electrical grid is limited or unavailable. These systems may include batteries or other energy storage devices, along with renewable energy sources, to generate and store electricity for powering homes, cabins, remote telecommunication stations, and other facilities.
5. Industrial Applications: Inverters are used in various industrial applications, such as motor drives, pumps, and machinery, to convert DC power from batteries or other sources into AC power for powering electrical equipment and controlling motor speed.
6. Consumer Electronics: Inverters are used in small portable devices, such as laptops, mobile phones, and other consumer electronics, to convert DC power from batteries or other sources into AC power for charging or powering these devices.
7. Emergency and Disaster Relief: Inverters are used in emergency and disaster relief situations to provide temporary power in areas affected by natural disasters, power outages, or other emergencies.

These are just some of the many applications where inverters are used. Inverters are versatile devices that play a crucial role in converting DC power to AC power for various purposes in a wide range of industries and settings.

What are the 3 types of inverters?

There are 3 major types of inverters – sine wave (sometimes referred to as a “true” or “pure” sine wave), modified sine wave (actually a modified square wave), and square wave.

Do inverters need maintenance?

While you don’t need to check your inverter daily, you should check it periodically to make sure everything’s working as expected. This includes looking on the inverter screen for any error codes, or a different light than normal. If anything seems amiss, call a professional to assess the situation.

Why You Need an Inverter?

An independent electric power system is one that is untethered from the electrical utility grid. Such systems vary in size from tiny yard lights to remote site homes, villages, national parks, or medical and military facilities. They also include mobile, portable, and emergency backup systems. Their common bond is the storage battery, which absorbs and releases power in the form of direct current (DC). In contrast, the utility grid supplies consumers with alternating current (AC) power. AC is the standard form of electricity for anything that “plugs in” to utility power (it is more practical for long distance transmission).

The inverter converts DC power to AC power, and also changes the voltage. In other words, it is a power adapter. It can allow a battery-based independent power system to run conventional appliances through conventional home wiring. There are many ways to use DC power directly, but if your electrical needs are beyond the simplest “cabin” level, you will need an inverter for many, if not all, of your loads (devices that use power).

DC flows in a single direction. AC alternates its direction many times per second. The standard DC voltages for home- size systems are 12, 24 and 48 volts. The standard for AC utility service in USA is 120 and 240 volts at 60 Hertz (cycles per second). In Europe and some countries in Latin America, Asia and Africa, it’s 220V or 230V at 50 Hertz. The inverter is used to reconcile these differences.

What to Consider When Comparing Inverters Before Purchasing

Where is the Inverter to be Used?

• Home – directly tied to the utility grid (grid-tie inverter)
• Cabin – standalone, completely off grid (off-grid inverter)
• Backup/emergency backup (hybrid inverter)
• Recreational vehicle
• Marine (marine inverter)
• Portable

Electrical Standards

• DC input voltage
• AC output voltage and frequency

Power capacity (Watts) – How much power can the inverter put out?

• Continuous rating
• Limited duration ratings
• Surge rating (for starting motors/pumps)
• Expandability (modularity, stackability)

Power quality (waveform)

• Some inverters produce “cleaner” power than others.
• Pure sine wave inverters
  • Ideal, smoothly alternating AC (like swing of a pendulum)
  • Equivalent (or superior) to grid power relatively expensive
• Modified sine wave inverters
  • Inferior waveform, choppy alternation (like pendulum forced by hammers)
  • Inexpensive
  • Adequate for many homes with simple needs, but about 5% of loads malfunction
  • May confuse digital timing devices in some appliances
  • May overheat power converters in some appliances/computers
  • May overheat surge protectors (don’t use them) causes some devices to buzz (some fluorescent lights, ceiling fans, transformers)
  • Reduces energy efficiency of motors and transformers by 10% or more, causes motors and transformers to run hotter
  • Generally reduces the reliability of appliances

Internal protection – How much abuse can it tolerate?

• Overload and surge protection
• Low voltage shutoff

Inductive load capability – Some loads accept the AC wave with a slight time delay. These are call inductive loads. Motors are the most severely inductive loads.

• Starting large motors (well pump, washing machine, power tools, etc.)

Learn more about inverter and latest trends on PVEurope or in our Solar Blog or on ourPower Inverter page.