12 volt inverter Sine wave inverters

1) Power Selection 

Must be powered by batteries or car cigarette lighter. Depending on the product's optional 12V, 24V, 48V. 

UPS is providing power to the critical load from power disturbances, voltage, frequency stabilization of power supply power supply after a mains failure, UPS can continue 220 volt power inverters‍ to provide some time to load power, to ensure the normal operation of the load used in this series UPS using high-frequency isolation transformer with an output double conversion architecture and advanced digital control technology, output stable, clean, uninterrupted with complete network management functions, generally UPS power supply has 1000w-20000w specifications. 

12 volt power inverters Sine wave inverter Introduction

Sine wave inverter schematic, of the difference between output and well-wave sine wave output high efficiency inverter square wave output, but for all the electrical sine wave 1500 watt power inverter‍ power supply design, the use is not always assured, Although you can apply to many appliances, but some appliances do not apply, or it will change indicators appliances. sine wave output of the inverter is no drawback in this regard, but there is the disadvantage of low efficiency. for this design a high efficiency sine wave inverter,

12 volt inverter Modified sine wave inverter applications

Modified sine wave inverter can be used in mobile phones, laptops, televisions, camcorders, CD players, various chargers, car refrigerator, game consoles, DVD players, 220 volt power inverters‍ power tools. Also widely used for field work such as travel or backup power, but also solve the problem of electricity shortage in remote areas. Become a supporting wind power inverters, solar photovoltaic projects, but also as the hospital's backup power, industrial and mining enterprises.

12v power inverter Modified sine wave inverter Precautions

Modified sine wave inverter should avoid "inductive load." In layman's terms, that the application of electromagnetic induction principle of making high-power electrical products, AC power inverters‍ such as motors, compressors, relays, fluorescent lights, and so on. These products need when starting a ratio to maintain normal operation (about 5-7 times) required a much larger current starting current. For example, a refrigerator power consumption during normal operation of about 150 watts, its starting power up to 1000 watts or more. In addition, due to the inductive load in an instant power or disconnect the power supply, will produce back-EMF voltage, peak voltage is much larger than this car inverter can withstand voltage, can easily cause car inverter instantaneous overload, the life impact of the inverter. 

When you use an ordinary multimeter to measure quasi-sine wave (modified sine wave) car inverter AC output voltage 20V display playful than 220 or so. 

Cause problems when running 220 volt power inverters‍ sophisticated equipment, can also cause high-frequency interference to communications equipment.

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12 volt inverter Modified sine wave inverter Overview

Modified sine wave is relative to the sine wave is concerned, and now the mainstream of the inverter output waveform, is modified sine wave. The waveform of the inverter Solar power inverters‍ main two categories, one is a sine wave inverter (ie, pure sine wave inverter), and the other is a square wave inverter. Sine wave inverter output power is the same as we use every day or even better sine wave AC power because it does not exist in the electromagnetic pollution. 

The square wave output of the inverter is the poor quality of the square wave alternating current, the positive maximum to the negative maximum value to almost simultaneously generated, so resulting in a dramatic effect on the instability of the inverter and the load itself. At the same time, its load capacity is poor, only 40-60% of the rated load, not with inductive loads. If the load carried by large, square-wave current third harmonic components contained enable capacitive currents flowing into the load increases, and in severe damage to the load of the power supply filter capacitor. 

For the above disadvantages, in recent years a modified sine wave (or modified sine wave, quasi sine wave, sine-wave, etc.) of the inverter, the output waveform from the positive maximum to a negative maximum time between intervals, using the results improved, but is still a sine wave correction by the broken line composed, still belongs to the scope of the square wave, the continuity is not good, and there is a dead 220 volt power inverters‍ zone (waveform diagram below). Modified sine wave inverters generally use non-isolated coupling circuit, and pure sine wave inverter with isolated coupling circuit design. Its price is also a lot of difference. Modified sine wave inverter switching power supply, not only eliminates the need for bulky power frequency transformer, but also greatly improve the efficiency of the inverter efficiency of 90%. 

Modified sine wave inverter switching PWM pulse width modulation to generate modified sine wave output, the inverter process, due to the use of a dedicated intelligent circuit and power FET, greatly reducing the power consumption of the system. And an increase in soft-start function, effectively ensuring the reliability of the inverter. If electricity is not very high quality, and it is able to meet the needs of most electrical equipment, AC power inverters‍ but it still exists 20% harmonic distortion, a problem occurs when you run precision equipment, can also cause high frequency of communications equipment interference.

12v power inverter Principle Power Inverter

Using a thyristor circuit to convert the direct current alternating current, this corresponds to a reverse process of the rectifier, the inverter defined. For example: AC power inverters‍ Application thyristor electric locomotives, so that when the downhill braking DC motor as a generator to run the locomotive's potential energy into electrical energy, trans go to the AC grid. Another example is the operation of a DC motor, to make it quick braking, the electric motor as a generator also allows operation of the motor kinetic energy into electrical energy, anti-delivered to the grid. 

The inverse DC into AC inverter circuit circuit called. In certain cases, the same set of thyristor rectifier circuit not only for, but also as an inverter. ‍

Converter in the inverter state, if the inverter AC side connected to AC power, the inverter converts DC to AC power with a frequency counter to go, called active inverter. If the change is not the AC side current grid connection, but directly to the load, which is a frequency inverter converts DC or AC adjustable frequency supplied to the load, then called passive inverter. AC frequency converter uses this principle to work. Except for Car power inverters‍ the active inverter DC reversible speed control system, but also for the exchange of spare lines rotor induction motor cascade control and other aspects of HVDC.

12 volt power inverters Car Inverter Introduction

Car inverter is designed for the production of small electrical appliances inverter, which is currently the most advanced DC - AC conversion of the product. The 12V DC vehicle into AC power inverters‍ a 220V AC provides commonly used, widely used in various electrical equipment, such as: mobile phones, laptops, cameras, camera, razor, air cleaners, current chargers and other electrical appliances. Is a car race, white, field work, travel, mobile office, special vehicles of essential goods, electric vehicle successfully solve problems.

12 volt inverter Car inverter Precautions

* Some chargers may be due to the converter outlet; 

* This product is DC24V car special, do not use in other voltages; 

* This product is a negative ground vehicle specific, positive ground vehicles can not be used; 

* This product is not applicable core transformer for 5W traveling charger. 

* May appear to "recharge" the former Pure sine wave power inverter‍ charging status indicator flashes red full off, the charging process becomes lit when charging. Red full off. This is a normal phenomenon. Does not affect the quality of any charge. 

* Some of the charger plug is inserted because of the direction that they can not work, this situation is to ask the conversion plug direction, then use.‍

12v power inverter Car power converter Cautions

Properly connected in the following order: 

1, start the car engine 

2, plug in the AC powered car (the case of switching off) 

3, open the car AC power switch 

4, plug in electrical AC power inverters‍ equipment 

5, after use, turn off the car AC power switch 

6, turn off your vehicle engine 

Avoid using vehicle power supply failed, inferior products may cause the principal burned car.‍

12 volt power inverters Principles and Applications of inverters in photovoltaic systems

1 . Requires a high efficiency. Due to the current high prices of solar cells , in order to maximize the use of solar cells, improve system efficiency, we must seek to improve the efficiency of the inverter .

2 . Requires a high reliability. Currently photo power sinverter‍ voltaic systems are mainly used in remote areas, many power plants unattended and maintenance , which requires an inverter circuit with a reasonable structure, strict screening of components and require an inverter with a variety of protection features such as input DC reverse polarity protection , AC output short circuit protection , thermal overload protection and so on.

3 . DC input voltage is required to adapt to a wide range, the terminal voltage of the solar cell and the intensity of sunlight varies with load changes , although the battery voltage of the solar cell has an important role, but because the battery voltage with the remaining battery capacity and internal resistance change fluctuate , particularly when the aging of the battery terminal voltage range is large, such as 12V battery , the terminal voltage may vary between 10V ~ 16V, which requires a larger inverter must be within the range of the DC input voltage vehicle power inverters‍ guaranteed to work , and to ensure that the AC output voltage stability .

12 volt power inverters Touch inverter terminals, especially with wet hands, otherwise it will cause electrical shock.

(4) For the normal operation of the inverter changes in their work environment, can not change its own connection should be a professional 

Or dealer to confirm the operation. 

(5) Do not put the battery Pure sine wave power inverter‍ into the fire, otherwise the battery will explode. And do not open or destroy batteries because batteries contain toxic to humans and harmful substances. 

(6) Minors must not use this product. 

(7) inverter operating environment should be well ventilated, temperature range -15 to 50 degrees Celsius environment, away from the fire source and the location out of direct sunlight. Not in the condensation, dust, high temperature operation in harsh environments. 

(8) Do not plug the inverter side of the blinds and do not use in the next heat source inverter (such as: electric heating, radiator, etc.) should be used in the shade. 

(9) When the machine is connected to the indoor power network, ensuring reliable inverter ground connection; diameter should meet the safety conditions of use, solar power inverter‍ if the diameter is too small, the line will become hot, it will lead to fires; cable do may be shortened.

12v power inverter inverter Features

1, the inverter output function:
After opening the car power inverter front panel of the "inverter switch", the upcoming DC battery power into AC rated voltage sine wave, and from the AC socket on the rear panel, the output terminals.
2, automatic voltage regulator function:
  When the battery voltage between points undervoltage and overvoltage point fluctuations within the rated power load changes, the machine has automatic voltage AC output function.
3, overvoltage protection functions:
  When the pure sine wave inverters battery voltage is greater than the "over-voltage point", the inverter will automatically cut off the AC output, buzzer alarm. Until the voltage drops to "over-pressure recovery point", the inverter automatically return to work before.
  4, undervoltage protection functions:
  When the battery voltage is below the "Brown-point", in order to avoid over-discharge and damage to the battery, the device will automatically cut off the inverter output. Buzzer alarm. Until the voltage rises to "voltage recovery point", the inverter automatically return to work before.

Power Inverter buy points

How to choose the correct ups power inverter mainly pay attention to the following points .
1 , the rated output voltage: within a predetermined fluctuation range of the input DC voltage is allowed , it means that the rated voltage of the inverter should be output . The stability of rated AC power inverters output voltage accuracy is generally defined as follows : In steady-state operation , the voltage fluctuation range should be a limit , such as the deviation does not exceed the rating of ± 3% or ± 5%. Under load mutations or other interfering factors affecting the dynamics of the output voltage deviation should not exceed the rating of ± 8% or ± 10%.
2 , the output voltage imbalance : Under normal operating conditions, the inverter output phase voltage unbalance ( reverse component of the ratio of positive sequence component ) should not exceed a specified value , usually expressed in% as 5 % or 8 %.
3 , the output voltage waveform distortion : When the inverter output voltage is sinusoidal , shall specify the maximum allowable waveform distortion ( or harmonic content ) . Usually to a total distortion of the output voltage waveform that its value should not exceed 5% ( 10% single phase output enable ) .
4 , rated output frequency of the vehicle power inverters inverter output AC voltage frequency should be a relatively stable value , usually frequency 50Hz. Under normal operating conditions the deviation should be within ± 1 %.
5 , the load power factor : the ability to characterize the capacitive load inverter with inductive load or . In the sine condition, the load power factor of 0.7 to 0.9 ( hysteresis ) , the rating is 0.9 .
6, rated output current : Indicates the inverter within the specified range of the rated output power factor of the load current . Some inverter products given is rated output capacity , the unit in VA or KVA said . The rated capacity of the inverter when the output power factor of 1 ( ie, purely resistive load ) , the rated output voltage of the rated output current of the product.
7 , rated output efficiency: The efficiency of the inverter under specified operating conditions , the output power to input power ratio , in%. Inverter efficiency at rated output capacity for full load efficiency of 10% at rated output capacity efficiency at low load efficiency.
8 , Protection: over-voltage protection : No voltage stabilization measures for the inverter output over-voltage protection measures due to the negative output cut from overvoltage damage.
Overcurrent protection : inverter over-current protection , should be able to ensure that a short circuit in the load current exceeds the allowable value or action from time to time , so from inrush current damage.
9 , starting characteristics : characterizing the performance of the inverter starting with a load capacity and dynamic work. The inverter should ensure reliable starting at rated load .
10 , the noise : the transformer power electronic device , the filter inductor , electromagnetic switches and other components are the fan noise is generated . Normal operation of the inverter , the noise should not exceed 80dB, small inverter noise should not exceed 65dB.

5kW off-grid PV inverter control strategy

SPWM control technology in a wide range of inverter circuit , we use a closed-loop PID control with a combination of negative feedback control of digital control strategy.
Generating a control pulse
This article is based on TI 's main chip , F2812 12 volt inverter There are two event manager EVA and EVB, each of which can generate a pulse output 8-channel , in which three pairs of complementary signal output from the full compare unit , each pair of complementary signals delay from the corresponding dead time timer generated , the event manager using the internal timer , and comparison means generates a corresponding pulse. Man in a pair of complementary output SPWM pulse signal and PWM signal output by one independent EVA, respectively Boost boost control circuit and an inverter circuit .
2 Output frequency calculations
SPWM inverter output frequency of the pulse signal is 50Hz, points SPWM output waveform of each sine wave cycle depends on the carrier frequency and the target output sine wave frequency SPWM pulse waves. As for the carrier frequency SPWM 18kHz, the frequency of the sine wave to be 220v inverters outputted respectively 50Hz, sine table needed for the point N
3 closed-loop negative feedback control
DSP2812 time detection output voltage input , the current value fed to the internal DSP , after the PI regulator to change the parameters associated register , controls the waveform of the drive pulses to achieve real-time closed-loop control , the control system block diagram shown in Figure 6, the system uses two closed loop negative feedback , depending on the feedback signal, the output of real-time adjustment , the output is stable. In addition, when the output current signal suddenly increases to exceed the maximum allowable current when off the PWM output to protect the inverter device from damage.

Functional skills

An additional output voltage
Within the limitations of the input DC voltage shake rule promised , it revealed that the performance of the extra voltage inverter should be able to output . Additional output voltage Solar power inverters accuracy is unchanged following general rules:
( 1 ) In the steady state 12 volt power inverters operation, the voltage should be a limit to shake limitations , such as its deviation does not exceed ± 3% or ± 5% extra value .
( 2 ) the load gradient ( extra load 0% → 50% → 100%) or other troubling elements under dynamic conditions affect the output voltage deviation should not exceed ± 8% additional value or ± 10%.
2 , refused to accept 24 volt power inverters  the value of the output voltage
Under the premise of normal tasks , three-phase voltage value of the inverter output satisfied (the weight of the positive-sequence reverse -weight ratio ) should not exceed the value of a rule , the general performance disclosed in% , such as 5 % or 8 %.
3, the output voltage waveform degrees off true
When the inverter output voltage is sinusoidal , the maximum waveform should rule out the promise of truth degrees ( or harmonic content ) . Mortal with a total output voltage waveform revealed truth degrees out performance , and its value should not exceed 5% ( single phase output promised 10% ) .
4 , an additional output frequency
Inverter output frequency of the AC voltage should be a relatively constant value , for the mortal frequency 50Hz. Under the premise of their normal tasks tend to be within ± 1 %.
5 , the load power factor
Inverter with rational characterization to load or capacitive loads. Under the premise of a sine wave , the load power factor of 0.7 to 0.9 ( hysteresis ) , the additional value of 0.9 .
6 , the additional output 220 volt inverter current ( or additional output capacity )
Revealed that the performance of the extra load power factor output current limitation rules inverter . Some of the inverter is given by the product of the additional output capacity , the unit in VA or KVA disclose performance. Additional capacity of the inverter when the output power factor of 1 ( ie, purely resistive load ) , the additional output voltage is the product of the additional output current .
7 , additional output efficiency
The efficiency of the inverter under the premise of the rule task , the output power to input power ratio, % disclose performance. Additional inverter output capacity efficiency under full load efficiency is at 10% efficiency of the output capacitor, the additional low -load efficiency .
8 , Maintenance
( 1 ) Over Voltage Maintenance: About the same way no voltage inverter , output over-voltage protection should be ways to cut from the negative output over-voltage damage.
( 2 ) Over-current Maintenance: overcurrent inverter maintenance , should be able to guarantee the onset of a short circuit in the load or the current value of real-time initiatives beyond the agreed time , so from inrush current damage .
9 , starting characteristics
Characterization of the inverter can start with functional and dynamic load tasks. The inverter should assure reliable starter in the extra load .
10 , the noise
Power electronic devices in the transformer, the filter inductor , the electromagnetic switch and other components are the fan noise will occur. Normal operation of the inverter , the noise should not exceed 80dB, small inverter noise should not exceed 65dB.

Simple production of the inverter

Since the start of the instantaneous current larger TV, you must consider the inverter waveforms, power margin, power factor, and so the production of soft-start control, so do it yourself  12v power inverter  requires professional knowledge and skills, more difficult, if not road easily damaged by electrical or inverter itself. Besides, 12V motorcycle battery capacity is 7 or 9 Ann Ann, separate 100W bulb for 40 minutes on the use of a 21-inch color TV also does not take 40 minutes, if it is an old battery, charging waited a long time, not a few comes to an end. The best solution is the choice of 300W UPS External around 50 Ah car battery.

Automotive power inverter for products

As TV, car microwave, juicer, tablets (eg ipad), portable radios, laptop computers, digital cameras, cell phones, CD and various chargers and other digital products provide safe and reliable AC power. With automatic protection function, make your converter, the battery can be effectively protected in extraordinary load, convenient and practical. Car power grid inverters with different models, different models corresponding to different power, in general, the 12 volt power inverters the power, the more applicable digital products, of course, fuel consumption is also large.
Universal 130W power supply can meet the general needs of digital products charge.

The working principle of automotive power inverter

Car power inverter is to convert DC car engine or car battery on alternating current , electrical products for general use , is a more convenient vehicle power conversion equipment . It is commonly used in automotive automotive supplies. Through which we can use the usual power to work with the city or charge electrical and digital products, such as televisions, laptops, cell phones , electric drill, emergency medical equipment , military vehicle equipment in the car , etc., can be used in various industries.
The output waveform according to points, car power AC power inverters sine wave output and can be divided into two kinds of square wave output . The former can provide uninterrupted , high-quality alternating current, can be adapted to any load , but the high technical requirements and costs , the circuit structure is more complex. The latter provides poor quality alternating current , and the load capacity is poor, can not pick " inductive load ." Despite many shortcomings, but its low technical requirements , small size, simple circuit, low prices. Taking these two advantages , currently on the market is to take a car power AC power inverters output analog sine wave program , compared with the effect of improving the use of a square wave , not only can drive inductive loads , and has a small size, light weight high conversion efficiency, output voltage stability , reliability , protection function characteristics.

What is an inverter?

 the DC power (battery, storage battery) into alternating current (typically 220V, 50Hz sine wave). It consists of inverter bridge, and filter control logic circuit. Widely used in air conditioners, home theater, electric wheel, power tools, sewing machines, DVD, VCD, computers, televisions, washing machines, range hoods, refrigerators, VCRs, massage, fans, lighting and so on. Abroad due to the higher penetration of the car to go to work or travel to a battery driven appliances and 800 watt inverter variety of tools to work with the inverter is connected. By car cigarette lighter inverter output is 12v power inverter  40W, 80W, 120W to 150W power specifications. Then a large number of power inverter to be received via cable on the battery. The appliances connected to the output of the power converter can use a variety of electrical appliances in the car. Appliances can be used are: cell phones, laptop computers, digital cameras, cameras, lighting, electric shavers, CD players, game consoles, handheld computers, power tools, car refrigerator and a variety of travel, camping, emergency medical appliances and so on.

Car inverter circuit

Car 12 volt inverter of the whole circuit can be divided into two parts, each part adopts one TL494 or KA7500 chip to form a control circuit, wherein the first part of the circuit is the role of the car battery to provide 12V DC, by the high frequency PWM (pulse width modulation) technique of switching power supply into 30kHz50kHz, about 220V alternating current; the second part of the circuit function is to use the bridge rectifier, filter, pulse width modulation and switching power output technology, 30kHz ~ 50kHz, 220V AC into 50Hz, 220V alternating current.

The main function of the vehicle inverter

The main function of vehicle DC AC power inverters is the battery 12V or 24V into 220V50HZ AC output, is the field operation, emergency power supplies. In your car is equipped with an inverter, battery car, your car can Everfount for AC electrical output of your 220V alternating current at any time and any place, for your mobile phone, electric wire, electric, acoustic, TV, fan, AC power portable computer to provide stable, to make your car really become mobile home

The working principle of solar inverter

The general structure of photovoltaic 6000 watt power inverters with three different inverter choice. Sunlight on solar modules are connected by connection mode, each module contains a set of tandem solar cell (Solar Cell) unit. DC solar module production (DC) in the order of several hundred volts voltage, number of specific values based on the module array illumination conditions, the temperature of the battery and series module and.
The primary function of this type of grid inverters is the DC input voltage is converted to a stable value. This function is realized by the boost converter, and the need to boost switch and the boost diode.

Photovoltaic power inverter function

24 volt power inverters not only has direct AC transform function, but also has to maximize the performance of solar cell function and fault protection function. To sum up the automatic operation and stop function, maximum power tracking control function, anti separate operation function (grid connected system), automatic voltage regulation function (grid connected system), DC detection function (grid connected system), DC grounding detection function (grid connected system). Here a brief introduction of automatic operation and stop function and maximum power tracking control function.

inverter

The inverter according to different sources of power, divided into coal power inverter, solar inverter, power inverter, power inverter. According to different purposes, divided into independent control of the inverter, grid connected inverter. The world solar inverter, and high efficiency, the European standard is 97.2%, but the price is more expensive, the inverter efficiency of domestic other is below 90%, but the price a lot cheaper than imported. In addition to power, waveform, is also very important to choose the inverter efficiency, efficiency is higher in the inverter to waste electricity, used for electrical power is more, especially when you use a small power system the importance of this more obvious.