Patent application date: 2004.0 1.07
Name switching power supply equipment
Publication (announcement)No. CN 15 18200
Publication date (announcement) August April, 2004
Category electricity
Certification date
Priority 2003. 1.7 JP2003-000975
Apply for (patent) Sharp Corporation.
Address Osaka Prefecture, Japan
Invented (designed) Tsukagoshi Hirotaka; Kitano Saburo
International application
International announcement
date of entry
Patent Agency Shanghai Patent and Trademark Office
Agent Li Jialin.
abstract
In the switching power supply device, when the switching power supply device works under normal working load, its working voltage is provided to the power factor improvement control circuit. Therefore, the step-up chopper can be controlled by improving the control circuit to improve the power factor of the device. In contrast, during the non-oscillation period, when the switch control circuit is in the gap oscillation mode, the power consumption is small, and the voltage induced in the auxiliary winding is reduced. Therefore, the voltage of the auxiliary power supply will also decrease. In addition, when the driving voltage supplied to the power factor improvement control circuit drops below its working voltage, the power factor improvement control circuit stops its function, thereby correspondingly reducing power consumption.
Sovereignty terms
1. A switching power supply device includes: a boost chopper for receiving a first DC voltage and converting the first DC voltage into an output second DC voltage, the boost chopper including a power factor improvement control circuit for improving the power factor; A series circuit for supplying a second DC voltage to the series circuit, and further comprising a primary winding of a transformer and a switching element; A switch control circuit for performing an oscillation function to drive and control the switching elements, so that the secondary winding of the transformer can induce voltage, and then rectify, smooth and provide it to a load with a third DC voltage, and when the load is less than a predetermined value, the switch control circuit can also perform a gap oscillation function, and the oscillation period and the non-oscillation period are repeated by the switch control circuit; The auxiliary power supply is used for rectifying and smoothing the voltage induced in the auxiliary winding of the transformer when the switching element is driven by the switching control circuit, and providing the voltage as a driving voltage to the power factor improvement control circuit and the switching control circuit; And a step-down circuit for reducing the driving voltage; In a non-oscillation period when the load is less than a predetermined value and the switching control circuit performs a gap oscillation function, the driving voltage provided to the power factor improvement control circuit is reduced to be lower than the working voltage by a voltage drop generated by the step-down circuit, and the power factor improvement control circuit can stop its operation, thereby reducing power consumption.
Turn-off transformers are generally used in pulse switching circuits, which are small in size, less in materials and low in price.
Unswitched transformer is a common power supply, coupling and output transformer (mostly using silicon steel sheet iron core), which has complex process, more materials and higher cost.
What's the difference between a switching transformer and a non-switching transformer? What are its advantages?
Switching transformers are generally used in switching power supply and other high-frequency circuit applications, with the advantages of small size, high efficiency and low price! Unswitched transformer is a commonly used low-frequency transformer, which is bulky, bulky and expensive.
In fact, the magnetic saturation coefficient of ferrite core in switching transformer is not as good as that of silicon steel core, which leads to the small energy transmitted by alternating current per hertz. However, because he works in a high-frequency circuit and exchanges energy many times in a unit time interval (1000 times that of a low-frequency transformer), the overall efficiency can reach dozens of times that of a low-frequency transformer.
Is there a difference in price between switching and not switching?
Low cost! ! ! For the same power transformer, the price of switching type is only about a quarter of that of non-switching type!