1. Field of the Invention
The present invention relates to the technology field of DC/DC converters, and more particularly to a controlling method for a multi-leg isolation DC/DC converter with wide input voltage scope.
2. Description of the Prior Art
With the development and advancement of industry and science technology, various electronic and electrical products are widely applied and used in human life, and it is well known that the electronic (electrical) products must be powered by electricity. However, since the power formation of the market electricity is AC power but not all electronic (electrical) products can be driven by AC power; for this reason, a variety of power converters are gradually designed and then proposed.
With reference to
Referring to
Accordingly, in view of the conventional regulated power supply and the conventional buck DC/DC converter still including drawbacks and shortcomings, the inventor of the present application has made great efforts to make inventive research thereon and eventually provided a controlling method for multi-leg isolation DC/DC converter with wide input voltage scope.
The primary objective of the present invention is to provide a controlling method for multi-leg isolation DC/DC converter with wide input voltage scope, in which a transformer having at least three primary winding coils and one secondary winding coil is provided in a multi-leg DC/DC converter. Moreover, a converter controlling module is provided to treat the DC input voltage and the DC output voltage received from the multi-leg DC/DC converter with an over voltage determination, therefore the converter controlling module is able to output a proper driving signal to a plurality of power switch sets of the multi-leg DC/DC converter for making the power switch sets be operated at different ON/OFF states, so as to make the transformer has a specific coil turn ratio. By such way, the DC input voltage of the multi-leg DC/DC converter would be automatic modulated for facilitating the multi-leg DC/DC converter to provide a stable DC output voltage.
Accordingly, to achieve the primary objective of the present invention, the inventor of the present invention provides a controlling method for multi-leg isolation DC/DC converter with wide input voltage scope, comprising following steps:
The invention as well as a preferred mode of use and advantages thereof will be best understood by referring to the following detailed description of an illustrative embodiment in conjunction with the accompanying drawings, wherein:
To more clearly describe a controlling method for multi-leg isolation DC/DC converter with wide input voltage scope according to the present invention, embodiments of the present invention will be described in detail with reference to the attached drawings hereinafter.
With reference to
As shown in
In the transformer of the multi-leg DC/DC converter 11, the coil turn ratio between the first primary winding coil NP1 and the secondary winding coil NS is n. The coil turn ratio between the second primary winding coil NP2 and the secondary winding coil NS is 2n. The coil turn ratio between the third primary winding coil NP3 and the secondary winding coil NS is 3n. The coil turn ratio between the first primary winding coil NP1 as well as the third primary winding coil NP3 and the secondary winding coil NS is 4n. The coil turn ratio between the second primary winding coil NP2 as well as the third primary winding coil NP3 and the secondary winding coil NS is 5n. The coil turn ratio between the first primary winding coil NP1, the second primary winding coil NP2 as well as the third primary winding coil NP3 and the secondary winding coil NS is 6n.
Moreover, the multi-leg DC/DC converter 11 is disposed with a full-wave rectifier unit 110, an output capacitor CO and an output resistor RO at the output end thereof, wherein the full-wave Rectifier unit 110 is coupled to the secondary winding coil NS, and the output capacitor CO is parallel to the output resistor RO and coupled to the full-wave Rectifier unit 110. Besides, the converter controlling module 12 is consisted of a counter 121, a feedback unit 123, an over voltage determining unit 122, a modulation unit 125, and a power switch driving module 126, wherein the feedback unit 123 is used for receiving the DC input voltage Vin. The over voltage determining unit 122 is coupled to the feedback unit 123 and the input end of the multi-leg DC/DC converter 11 for receiving the DC input voltage Vin and the DC output voltage VO, so as to respectively determine whether the DC input voltage Vin and the DC output voltage VO range between a user-set specific input voltage scope and a user-set specific output voltage scope. The modulation unit 125 is coupled to the over voltage determining unit 122 and has a drive mode selecting function. In the present invention, the modulation unit 125 is able to select the proper driving mode to drive the power switch sets (111, 112, 113, 114) according to an over voltage determination signal outputted by the over voltage determining unit 122. The power switch driving module 126 is coupled to the modulation unit 125 and the power switch sets (111, 112, 113, 114), used for driving the power switch sets (111, 112, 113, 114) according to the proper driving mode.
Continuously referring to
Inheriting to above descriptions, when the modulation unit 125 alternatively selects driving mode 4, the ON/OFF states of the power switch sets (111, 112, 113, 114) driven by the power switch driving module 126 are (ON, OFF, ON, OFF), respectively; therefore, the transformer of the multi-leg DC/DC converter 11 would has a specific coil turn ratio of 4n. Besides, When the modulation unit 125 selects driving mode 5, the ON/OFF states of the power switch sets (111, 112, 113, 114) driven by the power switch driving module 126 are respectively (OFF, ON, OFF, ON), and the specific coil turn ratio of the transformer of the multi-leg DC/DC converter 11 becomes to 5n. Moreover, When the modulation unit 125 selects driving mode 3, the ON/OFF states of the power switch sets (111, 112, 113, 114) driven by the power switch driving module 126 are respectively (ON, OFF, OFF, ON), and the specific coil turn ratio of the transformer of the multi-leg DC/DC converter 11 becomes to 6n.
Furthermore, as the operation state table of the power switch sets (111, 112, 113, 114) shown in
Thus, above descriptions have been completely and clearly introduced the multi-leg isolation DC/DC converter 1 with wide input voltage scope of the present invention. Next, a controlling method for the multi-leg isolation DC/DC converter 1 will be introduced in follows. Please refer to
However, before the step (S01) is executed, it must execute steps (SP1) and (SP2) in advance; such that the user is able to set the specific input voltage scope and the specific output voltage scope by using an external host 2 connected to the converter controlling module 12, and set a counter 121 of the converter controlling module 12 through the external host, so as to make the counter 121 count a converter-modulating period when the steps (1)˜(4) are executed. Therefore, the steps (1)˜(4) would be completed during the converter-modulating period. Besides, the plurality of power switch sets (111, 112, 113, 114) of the multi-leg DC/DC converter 11 are turned off when the steps (1)˜(3) are executed.
Please refer to
The above description is made on embodiments of the present invention. However, the embodiments are not intended to limit scope of the present invention, and all equivalent implementations or alterations within the spirit of the present invention still fall within the scope of the present invention.