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Anonymous users2024-02-06The difference between forward and flyback of switching power supply is as follows:
1. The principle is different: 1. The forward switching power supply refers to the switching power supply that uses the isolated coupling energy of the forward high-frequency transformer, and the corresponding flyback switching power supply. Forward excitation specifically refers to the switch tube.
When turned on, the output transformer acts as a medium to directly couple the magnetic field energy, and the electrical energy is converted into magnetic energy, which in turn is converted into electrical energy, and the input and output are carried out simultaneously. Recently, I encountered a place where electrical knowledge is quite complete, it is recommended that you go to see Zhejiang Emerson Electric, Zhejiang Emerson Electric shares a lot of electrical knowledge.
2. "Fly back" specifically refers to the fact that when the switch is turned on, the output transformer acts as an inductor, and the electrical energy is converted into magnetic energy, and there is no current in the output circuit at this time; Conversely, when the switch is turned off, the output transformer releases energy, the magnetic energy is converted into electrical energy, and there is a current in the output loop.
Second, the advantages are different.
Advantages of forward switching power supply: The power is larger than that of flyback switching power supply, and the utilization rate of output transformer is high, which is suitable for 100W 300W switching power supply.
Advantages of impact switching power supply: few components, simple circuit, low cost, small size, and can output multiple mutually isolated voltages at the same time.
Third, the disadvantages are different.
Disadvantages of forward switching power supply: the need to increase the back electromotive force.
winding, or topological drive, secondary plus 1 more rectifier inductor, high cost. Disadvantages of flyback switching power supply: the switch tube bears high voltage, the output transformer utilization rate is low, and it is not suitable for high-power power supply.
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Anonymous users2024-02-05What is the forward and reverse of switching power supply? These are basic theories and should be mastered.
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Anonymous users2024-02-04Working principle: transformer.
The polarity of the primary and secondary windings is opposite, which is probably the origin of the name flyback: aWhen the switch tube is turned on, the inductor current on the primary side of the transformer begins to rise.
At this time, due to the same name of the sub-beat, the output diode is turned off, the transformer is stored for energy, and the load is provided by the output capacitor. b. When the switch tube is turned off, the induced voltage of the primary inductance of the transformer is reversed, and the output diode is turned on at this time, and the energy in the transformer hits the hole to supply power to the load through the output diode, and at the same time charge the capacitor to replenish the energy just lost. Trembling
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Anonymous users2024-02-03Today I want to be a physics teacher, I believe that many girls are very distressed about the problem of the circuit when they go to school, why because they see the dizziness of those wires and wires entangled, and the back of those who see that they know themselves and see the formula he does not know have a headache, today I will tell you about the circuit knowledge that is not a headache called flyback switching power supply circuit.
Flyback switching power supply refers to the switching power supply that uses a flyback high-frequency transformer to isolate the input and output circuits. "Flyback" means that when the switch is turned on, when the input is high, the inductance in series in the output line is discharged; Conversely, in the case of a disconnected switch, the inductance in series in the output line is charged when the input is high. On the other hand, the "forward" switching power supply, when the input is high, the inductance in series in the output line is in the charging state, and when the input is high, the inductance in series in the output line is in the discharge state, so as to drive the load.
Flyback switching power supply working mode.
The circuit structure of the flyback switching power supply is relatively simple, and it is widely used in low-power circuits, and the two power supplies used in the 15kw Guangfeng hail inverter are of this structure. Flyback switching power supplies have three modes of operation: continuous mode, discontinuous mode and critical mode.
In the discontinuous operating mode, the power tube is turned on with zero current and the turn-on loss is small, while the secondary diode is turned off with zero current, which can ignore the reverse recovery problem, which will have some benefits for EMC.
I saw a detailed introduction to the principle of this kind of flyback power supply circuit, is it no stranger to it, then this teaching is very successful. Of course, teachers also rely on the ability of students to determine the quality of teaching, and everyone is quite smart. That's all for today's teaching, I hope you will continue to work hard.
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Anonymous users2024-02-02The forward type is mainly that the primary and secondary sides of the transformer are working all the time.
Flyback type means that when the switch tube is turned on, the primary side of the transformer is stored for energy, and the secondary side does not work, and the primary side releases energy when the switch tube is cut off, and the secondary side works.
The difference between forward and flyback is actually that the direction of the current induced by the secondary ring is different.
When the direction of the induced current is different.
The timing of the turn-on cutoff of the rectifier diode connected to the secondary ring is different.
In addition, the turn-on cut-off sequence of the switch tube connected to the main coil is also different.
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Anonymous users2024-02-01The forward transformer does not accumulate energy, but only undertakes coupling transmission, and the flyback transformer needs to store the energy in the opening process and release it during the shutdown process: the forward winding is in the same phase, and the flyback winding is inverted; The forward transformer does not need to adjust the inductance value, and the flyback type needs to be adjusted. There is a remanence circuit for remanence to prevent saturation, and it does not store energy, and it needs a storage coil and a freewheeling diode.
Flyback is not used. Because of the cost and their characteristics, the general flyback power supply is less than 100 watts, and the forward power supply is more than 100 watts, not that they cannot be interchangeable for power.
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Anonymous users2024-01-31Positive: in the primary switch tube.
Conduction. to the secondary level.
Flyback: Delivers energy to the secondary when the primary switch is closed.
The biggest difference.
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Anonymous users2024-01-30What is the forward and reverse of switching power supply? These are basic theories and should be mastered.
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Anonymous users2024-01-29Single-ended forward conversion: because the input power supply provides energy to the output capacitor and load through the transformer during the on-on period of the switch T, it is called forward converter; Single-ended flyback converter: It is a flyback converter because the transformer provides energy to the output capacitor and load during the shutdown of the switch T. As shown in Fig
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Anonymous users2024-01-28The main thing is that the transformer works differently. To put it simply, when the switch is opened, it works positively. Flyback works when shutting down.
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Anonymous users2024-01-27What is the forward and reverse of switching power supply? These are basic theories and should be mastered.
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