The knowledge and application of vehicle inverter

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What is a car inverter and an inverter power supply?

The car inverter (Power Inverter) is a kind of convenient car power converter that can convert DC12V DC into AC220V AC which is the same as the mains. Vehicle power inverters are widely welcomed in foreign markets. In foreign countries, due to the high penetration rate of automobiles, the inverter can be connected to the battery to drive the electrical appliances and various tools to work when going out to work or going out to travel. After China enters the WTO, there are more and more private vehicles in the domestic market. Therefore, the car inverter power supply as a converter for DC to AC used in mobile will bring a lot of convenience to your life. It is a kind of standing. Automotive electronic gadgets. The car inverter output through the cigarette lighter can be 20W, 40W, 80W, 120W up to 150W, power specifications. More power inverter power supplies 200W, 300W, 400W, 500W, 600W, 700W, 800W, 1000W, 1500W should be connected to the battery through the cable. Connecting the home appliance to the output of the power converter makes it easy to use various appliances in the car as if it were used at home. The appliances that can be used include: mobile phones, laptops, digital video cameras, cameras, lights, electric razors, CD players, game consoles, PDAs, power tools, car refrigerators, and various travel, camping, medical emergency appliances. Wait.

Knowledge of the use of vehicle power converters

First of all, we must choose a professional, regular factory production or distribution agent for automotive inverter products. Some users in China are convenient to put some DC DC appliances such as mobile phone chargers, laptops, etc. on the car without using their own 220V power supply and plugging them into the cigarette lighter directly. This is wrong. The battery voltage of the car is unstable. Directly taking electricity may burn the appliance. It is very unsafe and will greatly affect the service life of the appliance. Because the 220V power supply supplied by the original manufacturer is designed by the manufacturer for its electrical appliances, it has excellent stability.
In addition, when purchasing, you should check whether the car inverter has various protection functions, so as to ensure the safety of the battery and external devices. Also pay attention to the waveform of the vehicle inverter. The square wave converter will cause unstable power supply and may damage the electrical appliances used. Therefore, it is best to select the latest type of vehicle inverter with sine wave or modified sine waveform.

Car transformer use method

Plug and play

1. Insert the car inverter Power inverter into the car cigarette lighter socket and turn it to make it in good contact. Check the tightness between the cigar head and the socket when inserting. When it is too loose, open the two sides of the plug and insert it into the cigar head socket.

2. Check if the power indicator of the car inverter is lit.

3. Plug the power plug of the appliance to be used into the socket of the vehicle power converter.

Car inverter use attention

1. When unplugging the appliance in continuous use, be sure to confirm that the switch that is using the appliance is turned off, and then unplug the power cord. And unplug the car inverter

2. When replacing the fuse of the vehicle inverter, be sure to use the fuse of the same type and specification. If the fuse or wire other than the specified specification is used, it may cause abnormal overheating and fire.

3. Please clean the dirt of the inverter plug of the vehicle in time to avoid poor contact or abnormal overheating of the converter.

4. When using or not using the car inverter, please unplug the product from the cigar head socket and keep it in a safe place. Please strictly observe the precautions for using the appliance.

Correction of the application of sine wave car inverter

The modified sine wave car inverter can be applied to mobile phones, notebook computers, televisions, video cameras, CD players, various chargers, car refrigerators, game consoles, and DVD players. Descriptions of solar energy, wind power, ambulances, emergency rescue, power tools, car inverters, power converters:

1. Q: According to the output waveform, what are the inverters?

A: There are two main categories, one is the modified sine wave inverter and the pure square wave inverter, and the other is the sine wave inverter. The pure square wave inverter outputs a square wave AC with poor quality. The positive maximum value to the negative maximum value are generated at the same time (see the figure below), thus causing severe damage to the load and the inverter itself. Unstable effects. At the same time, its load capacity is poor, only 40 - 60% of the rated load, can not carry inductive load (see the following for a detailed explanation). If the load is too large, the third harmonic component contained in the square wave current will increase the capacitive current flowing into the load, and in severe cases, the load filter capacitor of the load will be damaged. In view of the above shortcomings, the modified sine wave inverter produced by our factory has a time interval between the positive maximum value and the negative maximum value (see the figure below), and the effect is greatly improved. In summary, The sine wave inverter provides high quality AC power and can drive any kind of load, but the technical requirements and cost are high. The modified sine wave inverter can meet most of our electricity demand, high efficiency, low noise, and moderate price, thus becoming the mainstream product in the market. The square wave inverter is manufactured using a simple multivibrator whose technology belongs to the level of the 1950s and will gradually withdraw from the market.

In general, the conversion efficiency of sine wave inverters and pure square wave inverters is 40% 60%.
The modified sine wave conversion efficiency is greater than or equal to 90%, so the modified sine wave inverter can meet most of our electricity demand, high efficiency, low noise, and moderate price, thus becoming the mainstream product in the market.

2. Q: What is an inductive load?

A: In layman's terms, high-power electrical products such as electric motors, compressors, relays, fluorescent lamps, etc., which are manufactured using the principle of electromagnetic induction. This type of product requires a much larger starting current (approximately 5.7 times) than the current required to maintain normal operation. For example, a refrigerator that consumes about 150 watts of electricity during normal operation can have a starting power of more than 1000 watts. In addition, because the inductive load is connected to the power supply or disconnected from the power supply, a counter electromotive voltage is generated. The peak value of this voltage is far greater than the voltage that the vehicle inverter can withstand, which easily causes the inverter for the vehicle. Instantaneous overloading affects the life of the inverter.

3. Q: What electrical appliances can the sine wave inverter be used for?

A: The modified sine wave inverter can be applied to notebook computers, televisions, stereos, camcorders, digital cameras, car refrigerators, printers, various chargers, palm power, game consoles, DVD players, mobile DVDs, various Power tools, etc. . . . . .

4. Q: How much power can the car cigarette lighter socket output?

Answer: Take power from the cigarette lighter socket, and the vehicle inverter can drive electric appliances with a power of more than 100 watts. Due to the use of non-compliant wires and cigarette lighter sockets on some circuits from the battery to the cigarette lighter socket, or some uninformed personal inverters deliberately extend the input wires of the inverter. It is convenient to use it to 1 meter (the car is a 12V power supply, and friends who have studied electronics know that the longer the low-voltage current input line, the greater the loss, the weaker the load capacity) and the line of the mobile phone charger is 1.5 meters. In every corner of the car, the loss in the circuit increases sharply when using a load that requires a large current, so that the voltage supplied to the inverter of the vehicle drops sharply to the critical point of the operation of the undervoltage protection circuit - 10 volts, resulting in vehicle use. The inverter stops supplying power. In order to solve this problem and ensure the normal, safe and reliable use of the vehicle inverter in the future, it is recommended that users buy the inverter products of the big factory and the wires of the circuit from the battery to the cigarette lighter socket to copper. High-quality wires with a core cross-section of 2.5 mm2 or more, and replace the cigarette lighter sockets when necessary.
Note: Some inverters do not have overcurrent, overheat protection, and can also start the appliance when the cigarette lighter is in poor contact, which will cause the cigarette lighter to overheat and damage the cigarette lighter.

5. Q: Why do I use a normal multimeter to measure the AC output of a sine wave (corrected sine wave) car inverter, the displayed voltage is 20V lower than 220 volts?

A: This is normal, because measuring the sine wave (correcting the sine wave) AC voltage should use a universal meter with a 'true RMS' file to get the correct reading.

6. Q: Can I use the car inverter when I turn off the car engine?

A: Yes. When using low-power appliances below 250 watts, a typical car battery can provide 60 120 minutes of power when the engine is turned off. If you only use a 50-60 watt laptop, the usage time is much longer. . YUESTAR's modified sine wave inverter is equipped with an undervoltage warning and undervoltage protection circuit. When the battery is used for a long time and the voltage drops to 10 volts, the undervoltage protection circuit starts, the output voltage is cut off and an alarm is issued to prevent it from happening. The accident that the engine could not be started because the battery voltage was too low. Therefore, the user can safely use the vehicle inverter with the engine off.

7. Q: How can I judge whether the inverter has overload, low voltage, over voltage, short circuit and over temperature protection?

Overload protection: After the 150W inverter is energized, open the switch and connect the load with more than 160W 180W. The inverter will reject the power supply with 220V output intermittently, and the red light will flash. 300W protection range 300W 350W 500W protection range 500W 550W

Low-voltage protection: After the inverter has been working for a period of time, the inverter's power is gradually reduced to 10.5V, the inverter alarms, and sensitive appliances (such as computers) should be stopped. Ignore the alarm voltage is reduced to 9.7V 10.3V inverter automatically shuts down,

Overvoltage protection: The charging system is faulty, and the battery voltage rises above 15.5V and the inverter stops working.

Short-circuit protection: When the inverter is working, the 220V output is short-circuited, the red light flashes, and it is eliminated in time.

Over-temperature protection: alarm and cut off the power supply when the temperature of the outer casing reaches 55 65 degrees after the inverter is fully loaded for a period of time.

Note: If you use a refrigerator that is much larger than the inverter's rated power, the air conditioner will start the inverter, and if it can be automatically protected, it is a good product with real protection function.

Wave inverter works:

YUESTAR Loctite modified sine wave switch inverter power supply produced by Yueqing Taiming Electronic Appliance Co., Ltd. not only saves the cumbersome power frequency transformer, but also greatly improves the efficiency of the inverter by 90%. It can be widely used as a backup power source for tourism or field operations, and can solve the problem of power consumption in remote power shortage areas. It can be used as a supporting inverter power source for wind power generation and solar photovoltaic projects, and can also be used as a backup power source for industrial and mining enterprises.

Circuit principle.

Its job is a DC-AC-DC-AC conversion process. In this process, the power loss of the system is greatly reduced due to the use of dedicated intelligent circuits and high-power FETs. And the soft start function is added to effectively ensure the reliability of the inverter.