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Advancements In Inverter Technology For Industrial Applications
Inverter is simply an electronic device that converts low voltage DC battery power 230 volts AC (Alternating Current) electrical power. They are used in applications ranging from microwaves laptops to satellite systems X-Ray machines etc.
Most industrial applications require high frequency high voltage power supply. These increased power requirements have lead to significant development in inverted technology.
Significant improvements have been made to the traditional pulse width modulations (PWM) Inverters to make power distribution system more efficient and more suitable to reactive power (var) compensation and harmonic filtering.
This includes using multilevel inverters, zero current switching and other power switching devises. Space application involves high power (hundreds of kilowatts to megawatts) systems. Large power conditioning mass reductions are required to enable this megawatt power system.
Therefore inverter design for space applications represents the state - of - the- art in power conditioning technology. Different features such as design parameters, output a characteristics, switching components etc of these inverters used in space application are discussed in the II part of the paper
An inverter is an electrical device that converts direct current (DC) to alternating current (AC); the converted AC can be at any required voltage and frequency with the use of appropriate transformers, switching, and control circuits.
Solid-state inverters have no moving parts and are used in a wide range of applications, from small switching power supplies in computers, to large electric utility high-voltage direct current applications that transport bulk power. Inverters are commonly used to supply AC power from DC sources such as solar panels or batteries.
There are two main types of inverter. The output of a modified sine wave inverter is similar to a square wave output except that the output goes to zero volts for a time before switching positive or negative. It is simple and low cost (~$0.10USD/Watt) and is compatible with most electronic devices, except for sensitive or specialized equipment, for example certain laser printers. A pure sine wave inverter produces a nearly perfect sine wave output (<3% total harmonic distortion) that is essentially the same as utility-supplied grid power. Thus it is compatible with all AC electronic devices. This is the type used in grid-tie inverters. Its design is more complex, and costs 5 or 10 times more per unit power (~$0.50 to $1.00USD/Watt).  The electrical inverter is a high-power electronic oscillator. It is so named because early mechanical AC to DC converters were made to work in reverse, and thus were "inverted", to convert DC to AC.
The inverter performs the opposite function of a rectifier.
From the late nineteenth century through the middle of the twentieth century, DC-to-AC power conversion was accomplished using rotary converters or motor-generator sets (M-G sets). In the early twentieth century, vacuum tubes and gas filled tubes began to be used as switches in inverter circuits. The most widely used type of tube was the thyratron.
The origins of electromechanical inverters explain the source of the term inverter. Early AC-to-DC converters used an induction or synchronous AC motor direct-connected to a generator (dynamo) so that the generator's commutator reversed its connections at exactly the right moments to produce DC. A later development is the synchronous converter, in which the motor and generator windings are combined into one armature, with slip rings at one end and a commutator at the other and only one field frame. The result with either is AC-in, DC-out. With an M-G set, the DC can be considered to be separately generated from the AC; with a synchronous converter, in a certain sense it can be considered to be "mechanically rectified AC". Given the right auxiliary and control equipment, an M-G set or rotary converter can be "run backwards", converting DC to AC. Hence an inverter is an inverted converter.
Controlled rectifier inverters
Since early transistors were not available with sufficient voltage and current ratings for most inverter applications, it was the 1957 introduction of the thyristor or silicon-controlled rectifier (SCR) that initiated the transition to solid state inverter circuits.
1.2 Advanced designs
H-bridge inverter circuit with transistor switches and antiparallel diodes
There are many different power circuit topologies and control strategies used in inverter designs. Different design approaches address various issues that may be more or less important depending on the way that the inverter is intended to be used.
1.3How Does a Power Inverter Work? Power Inverters for Cars
To those of us who think AC/DC is just a band, it is helpful to know what that means in terms of power. If you licked your fingers and touched them to a car battery's terminal, you will be experiencing DC, or direct current, power. This is the direct power that is housed in batteries and generators. When you plug your laptop cord into the wall outlet in your home, you are tapping into AC, or alternating current, power. Before direct current power can be used in our electrical devices, an alternator needs to convert the power. In the US, our electrical appliances require 110 AC power (if you have gone abroad, you know that sometimes you need to have a power converter because other countries often use other electrical voltage). A power inverter turns DC power into AC power. So if you have a battery or generator, you can run any electrical appliance. If a storm knocks your power out, you can power a space heater, hot plate, radio, or other necessities. When camping, you can bring all the comforts of home. On long trips in the car, you can plug in your laptop or cell phone to charge. It really is a very versatile and useful device to have.
AC/DC Power Inverter, Car Power Inverter, AC Power Inverter - So Many Choices, So Little Time
So you're at Home Depot wandering around the power inverter aisle. What now? Check the number of outlets the AC power inverter provides. Many have one to three outlets. Do you need a car power inverter or one that is more permanent? Again, think about what you will likely be powering. Before you head out to buy an AC/DC power inverter, it is important to know specifically what type of inverter you need. For instance, you can buy a $30 power inverter from Home Depot, a $450 solar power inverter, or a $2,000 industrial-grade model. You can buy one for your solar panels to increase energy efficiency or one for your RV for use on vacation. The first question is, "What do I need this for?" A close second is, "How much can I spend?" Keep these two factors in mind as you are shopping.
Related to the first question is the type of product you are going to be using the inverter for most often. For instance, if you will need to run oxygen concentrators, fax machines, electric shavers, garage door openers, and high voltage cordless tool chargers, you will need a true-sine inverter. These produce power that is equal - or better - to that from the power grid. For virtually every other electrical appliance, a modified-sine inverter is sufficient. The power is not identical to that which comes from the grid. Instead of a smooth sine wave, it produces one that is choppy. These AC power inverters are perfectly capable of running everything from televisions to computers.
Also consider where you are going to use the inverter. If you want one that will plug into your vehicle cigarette lighter, you should use an inverter that is rated under 300 watts. If the 12-volt lighter has to draw more power than that, it will strain and eventually blow. But 12 volts is enough to power household appliances, computers, and TVs smaller than 27 inches. 600 watt inverters can also be used with 12-volt sources. They can power larger TV, household appliances, bread machines, and 5 amp tools. The next step up for large appliances, larger power tools, microwaves, toasters, and hairdryers requires a 1750 watt appliance. 3000 watts of power can handle nearly all household appliances and office equipment. The wattage you need will depend on the amps needed to run your device; generally power inverters are divided into under 300, 300, 600, 1800, and 3000 and above watts generated. To convert the amps your device takes to watts, simply take the amp number and multiply it by 120; that is your watt
A Solar inverter or PV inverter is a type of electrical inverter that is made to change the direct current (DC) electricity from a photovoltaic array into alternating current (AC) for use with home appliances and possibly a utility grid.
A PV inverter installed in an attic
Solar inverters may be classified into three broad types:
• Stand-alone inverters, used in isolated systems where the inverter draws its DC energy from batteries charged by photovoltaic arrays and/or other sources, such as wind turbines, hydro turbines, or engine generators. Many stand-alone inverters also incorporate integral battery chargers to replenish the battery from an AC source, when available. Normally these do not interface in any way with the utility grid, and as such, are not required to have anti-islanding protection.
• Grid tie inverters, which match phase with a utility-supplied sine wave. Grid-tie inverters are designed to shut down automatically upon loss of utility supply, for safety reasons. They do not provide backup power during utility outages.
• Battery backup inverters. These are special inverters which are designed to draw energy from a battery, manage the battery charge via an onboard charger, and export excess energy to the utility grid. These inverters are capable of supplying AC energy to selected loads during a utility outage, and are required to have anti-islanding protection
• Solar inverters use special procedures to deal with the PV array, including maximum power point tracking and anti-islanding protection.
Normally, grid-tied inverters will shut off if they do not detect the presence of the utility grid. If, however, there are load circuits in the electrical system that happen to resonate at the frequency of the utility grid, the inverter may be fooled into thinking that the grid is still active even after it had been shut down. This is called islanding.
An inverter designed for grid-tie operation will have anti-islanding protection built in; it will inject small pulses that are slightly out of phase with the AC electrical system in order to cancel any stray resonances that may be present when the grid shuts down.
Since 1999, the standard for anti-islanding protection in the United States has been UL 1741, harmonized with IEEE 1547. Any inverter which is listed to the UL 1741 standard may be connected to a utility grid without the need for additional anti-islanding equipment, anywhere in the United States or other countries where UL standards are accepted.
Maximum power point tracking (MPPT)
Main article: Maximum power point tracker
I-V curve for a solar cell, showing the maximum power point Pmax.
Maximum power point tracking is a technique that solar inverters use to get the most possible power from the PV array. Any given PV module or string of modules will have a maximum power point: essentially, this defines current that the inverter should draw from the PV in order to get the most possible power (power is equal to voltage times current).
Grid tie inverters
Main article: Grid tie inverter
Many solar inverters are designed to be connected to a utility grid, and will not operate when they do not detect the presence of the grid. They contain special circuitry to precisely match the voltage and frequency of the grid.
Stand-alone inverters – that is, inverters that are designed to be used without the presence of the electrical utility grid – can be run from PV panels and batteries using a charge controller. The charge controller regulates the input from the PV and the batteries, regulates the battery output, and handles charging the batteries.
2.2Solar Power Inverters
RS2332 / RS485
The solar inverter performs the conversion of the variable DC output of the PV cells into a clean sinusoidal 50- or 60 Hz current.
Solar Power Inverter
The solar inverter is a critical component in a solar energy system. It performs the conversion of the variable DC output of the Photovoltaic (PV) module(s) into a clean sinusoidal 50- or 60 Hz AC current that is then applied directly to the commercial electrical grid or to a local, off-grid electrical network. Typically, communications capability is included so users can monitor the inverter and report on power and operating conditions, provide firmware updates and control the inverter grid connection. Depending on the grid infrastructure wired (RS-485, CAN, Power Line Communication, Ethernet) or wireless (Bluetooth, ZigBee/IEEE802.15.4, 6loWPAN) networking options can be used.
At the heart of the inverter is a real-time microcontroller. The controller executes the very precise algorithms required to invert the DC voltage generated by the solar module into AC. This controller is programmed to perform the control loops necessary for all the power management functions necessary including DC/DC and DC/AC. The controller also maximizes the power output from the PV through complex algorithms called maximum power point tracking (MPPT). The PV maximum output power is dependent on the operating conditions and varies from moment to moment due to temperature, shading, soilage, cloud cover, and time of day so tracking and adjusting for this maximum power point is a continuous process. For systems with battery energy storage, the controller can control the charging as well as switch over to battery power once the sun sets or cloud cover reduces the PV output power. The controller contains advanced peripherals like high precision PWM outputs and ADCs for implementing control loops. The ADC measures variables, such as the PV output voltage and current, and then adjusts the DC/DC or DC/AC converter by changing the PWM duty cycle.
The C2000 in particular is designed to read the ADC and adjust the PWM within a single clock cycle, so real time control is possible. Communications on a simple system can be handled by a single processor, more elaborate systems with complex displays and reporting on consumption and feed-in-tariff pay back may require a secondary processor, potentially with ethernet capability like the Stellaris Cortex M3 parts. For safety reasons, isolation between the processor and the current and voltage is also required, as well as on the communications bus to the outside world.
3.3Advanced inverter technology
Mitsubishi Electric Advanced Inverter Technology provides high-speed cooling and heating with extra energy savings compared to non-inverter models.
Vector-wave Eco Inverter
This inverter produces the most efficient waveform in response to variations in compressor motor frequency. Operating efficiency is improved throughout the entire speed range, leading to a reduction in annual electricity cost.
DC Fan Motor
Our outdoor units are equipped with an extremely efficient DC motor. Depending on operating conditions, efficiency is up to 60% greater than equivalently rated AC motors.
Magnetic Flux Vector Sine Wave Drive
A microprocessor converts the motor's electrical current waveform into a sine waveform (180°conductance), enabling the motor winding ratio to be increased while energy loss is reduced.
Econo Cool Temperature Control
"Econo Cool" is an intelligent temperature control feature that adjusts the airflow distributed in the room depending on the air outlet temperature. Temperature settings can be raised 2°C without any loss in room comfort. That's equal to a 20% gain in energy efficiency.
Abstract : This report gives the results of all Program tasks for the Advanced Inverter Technology Program. APL has three existing series resonant inverter-based power converters. The control and protection circuits are different for the three units. The purpose of this program was to produce a control and protection architecture and functional circuits that would work with all three power stage topologies. The requirements for the three existing power stages were determined. The three existing control and protection circuits were analyzed. An IC technology study was performed to determine the optimum technology and fabrication method for SRI control and protection circuits. A control and protection architecture utilizing common functional circuits that would work with the three existing topologies as developed and block diagrams drawn. The functional tasks were partitioned into five custom parts. The requirements for the custom parts were described. A study was performed to assess the potential present and future functions for a microprocessor in a series resonant inverter. A packaging and thermal study was performed to investigate the problems associated with space deployment of a 200-kW series resonant inverter. Keywords include: Control Architecture, Converter Control, Converter Protection, Gate Control, Generalized SRI Control and Protection, Power Converter, and Series Resonant Inverter Control.
ABB’s new inverter to feed photovoltaic power into the grid, safely and reliably.
ABB’s first solar inverter, the PVS800, is a reliable, economic and compact solution for connecting photovoltaic arrays to the grid. It is the latest addition to ABB’s wide portfolio for the solar industry
By ABB communications
Photovoltaic energy is currently more expensive than conventional, higher-carbon energy sources, but it’s getting cheaper. Over the next five years, as photovoltaic module production capacities continue to grow and economies of scale are achieved, the cost of photovoltaic-based power generation is expected to fall to the same levels as peak-rate electricity from conventional sources.
ABB has a broad offering for the solar market, including power and automation products and systems that maximize energy yield in solar installations and maximum return on investment for plant operators.
ABB has a broad offering for the solar market to maximize energy yields and return on investment for plant
Photovoltaic plants, in which solar energy is collected by light-sensitive panels and converted directly into electricity, rely on inverters to convert the direct current produced by the cells into alternating current, which is needed for electricity distribution. ABB’s new product, the central inverter, PVS800, feeds clean solar power into medium- or low-voltage grids via transformers and switchgear (both available from ABB).
Available in power ratings of between 100 and 500 kW, the new inverter can be used in both industrial-scale photovoltaic power plants and for medium-sized power plants installed on the roofs of commercial or industrial buildings. ABB’s central inverter is reliable, durable, easy to install, and extremely compact. In fact, it is the one of the most compact models currently available on the market.
Photovoltaic cells produce direct current, which must be converted into alternting current to be fed into the grid.
The new solar inverters are based on tried-and-tested technology developed by ABB for use in variable-speed drives (devices that control the flow of power to electrical equipment, tailoring performance to the needs of the task in hand). ABB is the world leader in this type of technology and by adapting it for use in solar inverters, has produced a highly reliable product that is expected to provide at least 20 years of trouble-free operation. The new inverters are also supported by ABB’s proven maintenance and service offering.
Growth in the solar industry is currently supported by governments, in various parts of the world, making generous payments to producers who feed their solar power into the grid. The aim is to raise production volumes and achieve the economies of scale that will reduce the cost of solar generation. Once the cost of solar power reaches parity with other forms of generation, the industry will continue to grow, driven by environmental concerns. This point, which is known as ”grid parity,“ is expected to be reached first in regions with high levels of solar radiation and high conventional electricity peak prices, California and Italy, for example.
While continuing growth of the solar sector is highly desirable from the environmental point of view, it may cause problems for the grid. The irregular flow of solar power into the grid, caused by changes in the weather, can cause disturbances in the grid and interruption of power supplies for consumers.
On a small scale, disturbances can be corrected, but to deal with the fluctuations that large quantities of renewable power generation will bring, particularly if it comes from large numbers of small generators distributed across the grid, the system needs to change. The current power network needs to be better monitored, more automated and better able to respond to disturbances in power flows. It needs to be more intelligent. In short, we need a smarter grid.
A number of the technologies needed for the development of smart grids are already available as part of ABB’s existing portfolio, and ABB is at the forefront of development projects working to implement these solutions in the grid. While true smart grids are still a vision for the future, ABB is helping to drive the evolution of our power systems, and ABB’s solar inverters are part of the plan.
2.4 The 4 Newest Solar Inverters on the Market
One of our recent blog posts claims that Solar Inverters Make It All Happen. These battery-powered devices are part and parcel to most solar home energy systems, converting the DC current from solar panels into a useable AC current within the home. Therefore, homeowners shopping around for solar panels should know their share about solar inverters, too.
Important attributes of your potential inverter include:
• matching the wattage output of your desired solar panels
• having the surge power to supply electricity to large appliances, and
• having high efficiency, among other features.
The latest inverters on the market, however, may make the inverter selection process a whole ot easier. Here’s why 4 new inverters are shaking things up.
1. Northern California based Enphase Energy just raised $6.5 million in funding to develop and manufacture the micro-inverter, a device so small it can be built into individual panels. This capacity for panels to convert the current internally could potentially eliminate the need to purchase a separate inverter. Though the product isn’t available just yet, it is well on its way.
2. PV Powered has a new inverter on the market, the enhanced 30kW Commercial Solar Inverter. Meant for small commercial applications to help grow a business, PV Powered asserts that their new inverter is more flexible and efficient, as well as easier to install. New capabilities of the product include:
o expanded DC input voltage range to ensure compatibility with most or all PV modules on the market
o increased energy harvest to help identify the optimal power point more quickly and accurately deliver usable power under all operating conditions
o new cabinet features to make it easier to install and set up
3. MorningStar’s SureSine Inverter just received UL and cUL Certification, signifying compliance with electrical safety and code standards. With 25 years of experience in off-grid photovoltaics, the company’s new product is designed specifically for rural PV electrification.
4. Finally, the new inverter by Fraunhofer ISE has the highest efficiency rating reported for PV inverters to date. At 98.5 percent efficiency, the ISE inverter will enable PV systems to yield
greater energy overall. According to Solar Energy News, ISE engineers are specialists in transformerless inverters, considered more efficient, cheaper, and lighter than devices with transformers.
XPower Inverters - Digital
VIEW HI-RES IMAGE
400 & 800 Watts - 120 Vac / 60 Hz
Designed to power electronics while on the go, our new compact digital power inverters combine innovative industrial design with an advanced interactive LED display.
Portable electric power for mobile offices
Designed to power electronics while on the go, our new compact digital power inverters combine innovative industrial design with an advanced interactive LED display. This provides the user with instant feedback on input current and output voltage and valuable troubleshooting guidance through Fault Codes. These new digital inverters provide a convenient and powerful way to access AC power.
• Inverter 400: 320 watts continuous power with 640 watts surge
• Inverter 800: 640 watts continuous power with 1280 watts surge
• Two AC receptacles for connecting multiple loads
• Small Profile for easy storage
• Digital LED instantly provides information on:
o the amount of wattage an application is drawing
o the amount of voltage remaining in the battery
o fault codes making troubleshooting easier
• Overload and over temperature shutdown
• Over voltage protection
• Low voltage alarm
• Low voltage shutdown
• Household applications: small appliances and portable work light
• Entertainment electronics: video game console, 27” TV and stereo
• Office equipment: desktop computer system, laptop, printer and fax
Conventional CCFL inverter
A CCFL inverter is a device (an inverter) for providing drive power to a Cold Cathode Fluorescent Lamp (CCFL). CCFLs are often used as inexpensive light units in electrical devices.
1. Small form and structure
2. Switchover efficiency over 80%
3. Adjustable light
1. widely used in backlights for LCDs
2. used in ultrathin lamp cases, such as the rear lamp for advertising signs
3. used in auxiliary illumination and lighting devices
3.2 ECE 6204 Advanced Inverters for Distributed Generation and Renewable Energies (3C)
Power inverters in distributed generation and renewable energies such as fuel cells, photovoltaics, and wind power. Inverter circuit topologies for stationary power applications, including voltage source, current, source, and Z-source inverters. Modeling and control for single-phase and three-phase inverters. Advanced control techniques for standalone and grid-tie modes using admittance compensation, proportional resonant controller, one-cycle control, and dq-control. System level control issues such as phase-lock loop for synchronization, reactive power generation, and control for rotational generators.
What is the reason for this course?
Distributed generation and renewable energies require special types of power electronics and control that are not found in traditional textbooks and courses. Conventional power systems do not involve electronics, and their dynamics and control are slow. With power electronics and advanced control, the distributed generation and renewable energies can penetrate the existing power system. This course intends to teach circuits and control that are applicable to these new systems.
Why are these prerequisites or corequisites required?
ECE4224 teaches circuit topology analysis, modeling and control design of basic dc-dc converters, which are essential background of the dc-ac inverter study.
Department Syllabus Information:
Major Measurable Learning Objectives:
• evaluate the inverter circuit suitable for distributed generation and renewable energy applications,
• design inverter circuits and their modulation techniques for ac power production
• model inverters in dynamic system formats,
• design advanced controller for standalone loaded inverters,
• design advanced controller for grid-tie inverters,
• design advanced controller for rotational generator based inverters, and
• simulate inverter along with controllers for distributed generation and renewable energy applications.
Solar power system working principle, how to build a solar power system?
4.inverter there are only DC 12V/24V 48V from the batteries and solar panels, to power the 220V/110V AC appliance, it is need to converte the DC power into AC power by inverter.
A stand alone ( or off-grid) solar power system always combined by solar modules, solar controller(regulator), and batteries. If alternating current(AC) 220V or 110V needed, there also will be an inverter.
The function for each parts:
1.solarinverter: many pieces of solar cells assembled together to create a solar module, this solar module is the hard-core of a solar power system, also the most cost parts. The solar modules absorb sunlight and convert to electricity to store in battery or power the loads.
2.Solar controller: (or solar regulator): controlling the working state of whole solar power system, also Protect the battries from over charge and over dis-charge. A good controller also have a temperature compensate function when used in the area with big temperature difference. Also there are other optional function such as timer and photoswithch.
3.Batteries: commonly used the Lead Acid batteries, in the mini systems, also used the NI-Mh, Ni-Cd or lithium battery. It’s function was store the electricity generated by solar modules when there was sunlights, and release it when needed.
Factors for designing a solar power system:
1. where to use the solar system, how about the solar irradiation condition in the area.
2. Total loading power(KW), and daily consumption(KWH).
3. what will be the system output voltate, AC or DC required?
4. Working time on each day for the solar system.
5. system Backup days in continuous raining and cloudy condition.
Inverters can be used in a number of applications. The use can vary from small applications in a personal computer to large industrial complexes which require bulk power. An inverter is basically a logic gate that converts input into output and both of them are in opposite state. It implies that if input is false then output is true and vice-versa.
Inverters ensure an uninterrupted power supply. They can vary in size according to their capacity. Inverters can have one-switched as well as two-switched modes of power supply.
A simple inverter consists of an oscillator. This oscillator drives a transistor. The result is interruption of the direct current which is incoming, creating a square wave which passes through a transformer to produce the output. The more advanced inverters have started using thyristors and other forms of advanced transistors.
An inverter has several other parts, such as capacitors and inductors. They ensure the smooth and uninterrupted supply of current from the inverter. The best way to judge the quality of an inverter is to look at its pulse rating. A 3-pulse implies that the inverter is using three transistors. It is a relatively simple arrangement.
Inverters offer a cleaner output than many generators. That is why they are preferred as a source of power, especially in those areas which are environmentally sensitive. Though the quality of power supplied by simple inverters may not be that good, there are other, more advanced inverters which do not give you such problems.
There are companies which make customized inverters available on demand. Before you buy one, find about the maintenance costs and the effort that is necessary to maintain it. Some of the inverters might not be that expensive, but their maintenance is.
Inverters provides detailed information on Inverters, Power Inverters, Welding Inverters, Refurbished Inverters and more. Inverters is affiliated with Uninterruptible Power Supplies.
1.1 DC power source utilization
1.2 Uninterruptible power supplies
1.3 Induction heating
1.4 HVDC power transmission
1.5 Variable-frequency drives
1.6 Electric vehicle drives
1.7 Air conditioning
1.8 The general case