Patent Description:
An electronic device, such as a portable terminal, uses a power conversion device to supply operating power required for the operation of internal devices (e.g., a processor, a memory, and the like).

The power conversion device may convert a voltage supplied from a battery into a voltage suitable for the internal devices of the electronic device.

The power conversion device includes a buck converter for stepping down an input power, a booster converter for stepping up an input power, and the like.

<CIT> discloses a voltage converting circuit including a plurality of first capacitors that are charged by a power source, a second capacitor, connected in parallel to the plurality of first capacitors, which is able to be charged to a voltage that is supplied to a load circuit, and a plurality of switching circuits, provided in such a way as to correspond to the plurality of first capacitors, each of which switches states of connection between its corresponding first capacitor and the second capacitor. The first capacitors are sequentially connected to the second capacitor through the corresponding switching circuits as charging voltages of the first capacitors reach a predetermined connection voltage that is higher than a charging voltage of the second capacitor so that the first capacitors are not short-circuited with each other.

<CIT> discloses a switched capacitor (SC) converters with excellent voltage regulation, high conversion efficiency, and good suitability for a wide range of applications are provided. An switched capacitor converter can include at least two switched capacitor sub-circuits, and at least one of these switched capacitor sub-circuits can be of variable gain. One switched capacitor sub-circuit can convert the input voltage of the switched capacitor converter to an output voltage close to the desired output voltage value for the switched capacitor converter, and another switched capacitor sub-circuit having variable gain can convert the input voltage to an output voltage with a high resolution of small discrete voltage steps.

<CIT> discloses a hybrid converter achieves high efficiency with an inductor positioned at the lower current path that significantly decreases inductor loss by having the DC component of inductor current reduced. The circuit also features reduced inductance requirement by reducing the voltage swing blocked by the inductor. As a result, it turns to benefit of both efficiency improvement and better integration. Less voltage stress for switches is also an important advantage to switching loss reduction and switching frequency increase which in turns enables passive component size reduction. The circuit in this invention can be realized for both step-down and step-up power conversion as well as bidirectional power flow is available. For simplicity and cost, some of switches can be replaced with passive switches such as diodes which highly simplifies the converter circuit implementation.

<CIT> discloses an electric energy storage apparatus can generate an AC output in a low-loss and low-noise manner without using a DC-DC converter or an inverter. The electric energy storage apparatus comprises: an electric energy storage module group formed by connecting in series electric energy storage modules each comprising one or more electric energy storage elements; a balancing circuit electrically connected to the electric energy storage module group and configured to adjust a voltage to be applied to each of the electric energy storage modules; a first switch group comprising switches each in a path connecting a first terminal and a terminal of one of the series-connected electric energy storage modules; and a second switch group comprising switches each in a path connecting a second terminal and a terminal of one of the series-connected electric energy storage modules. The electric energy storage apparatus may perform a switch changeover in the switch groups.

A power conversion device according to claim <NUM> is presented.

A power conversion method according to claim <NUM> is presented.

<FIG> is a block diagram illustrating an electronic device <NUM> in a network environment <NUM>.

The electronic device <NUM> may communicate with the electronic device <NUM> via the server <NUM>. The electronic device <NUM> may include a processor <NUM>, memory <NUM>, an input device <NUM>, a sound output device <NUM>, a display device <NUM>, an audio module <NUM>, a sensor module <NUM>, an interface <NUM>, a haptic module <NUM>, a camera module <NUM>, a power management module <NUM>, a battery <NUM>, a communication module <NUM>, a subscriber identification module (SIM) <NUM>, or an antenna module <NUM>. At least one (e.g., the display device <NUM> or the camera module <NUM>) of the components may be omitted from the electronic device <NUM>, or one or more other components may be added in the electronic device <NUM>. Some of the components may be implemented as single integrated circuitry.

The processor <NUM> may execute, for example, software (e.g., a program <NUM>) to control at least one other component (e.g., a hardware or software component) of the electronic device <NUM> coupled with the processor <NUM>, and may perform certain data processing or computation.

The memory <NUM> may store certain data used by at least one component (e.g., the processor <NUM> or the sensor module <NUM>) of the electronic device <NUM>. The certain data may include, for example, software (e.g., the program <NUM>) and input data or output data for a command related thererto.

The receiver may be implemented as separate from, or as part of the speaker.

The connecting terminal <NUM> may include, for example, a HDMI connector, a USB connector, a SD card connector, or an audio connector (e.g., a headphone connector).

The communication module <NUM> may include a wireless communication module <NUM> (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module <NUM> (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). These certain types of communication modules may be implemented as a single component (e.g., a single chip), or may be implemented as multi components (e.g., multi chips) separate from each other.

The antenna module <NUM> may transmit/receive a signal or power to/from an external entity (e.g., an external electronic device). The antenna module <NUM> may be formed of a conductor or a conductive pattern and may further include any other component (e.g., RFIC). The antenna module <NUM> may include one or more antennas, which may be selected to be suitable for a communication scheme used in a specific communication network, such as the first network <NUM> or the second network <NUM> by, for example, the communication module <NUM>. Through the selected at least one antenna, a signal or power may be transmitted or received between the communication module <NUM> and the external electronic device.

The electronic device may be one of certain types of electronic devices.

It should be appreciated that certain embodiments of the present disclosure and the terms used therein are not intended to limit the technological features set forth herein to particular embodiments and include certain changes, equivalents, or replacements for a corresponding embodiment.

Certain embodiments as set forth herein may be implemented as software (e.g., the program <NUM>) including one or more instructions that are stored in a storage medium (e.g., internal memory <NUM> or external memory <NUM>) that is readable by a machine (e.g., the electronic device <NUM>).

According to an embodiment, a method according to certain embodiments of the disclosure may be included and provided in a computer program product.

The module or programming module of the present disclosure may include at least one of the aforementioned components with omission of some components or addition of other components. The operations of the modules, programming modules, or other components may be executed in series, in parallel, recursively, or heuristically. Also, some operations may be executed in different order, omitted, or extended with other operations.

<FIG> schematically illustrates a configuration of a power conversion device according to various embodiments of the disclosure.

Referring to <FIG>, a power conversion device <NUM> (e.g., the power management module <NUM> of <FIG>) according to various embodiments of the disclosure may include a power supply unit <NUM> (e.g., the battery <NUM> of <FIG>), a capacitor unit <NUM>, a controller <NUM> (e.g., the processor <NUM> of <FIG>), a switch unit <NUM>, a converter <NUM>, a load <NUM>, and a feedback controller <NUM>.

The power supply unit <NUM> may supply a direct current (DC) voltage to the capacitor unit <NUM> and the converter <NUM> through power terminals (+, -). According to an embodiment, the power supply unit <NUM> may include a battery (e.g., the battery <NUM> of <FIG>) which supplies a direct current voltage of a predetermined level. According to an embodiment, the power supply unit <NUM> may be an external power source or an internal power source of the power conversion device <NUM>.

The capacitor unit <NUM> may accumulate, for example, a voltage supplied from the power supply unit <NUM>. According to an embodiment, the capacitor unit <NUM> may include a plurality of capacitors (e.g., a first capacitor <NUM>-<NUM>, a second capacitor <NUM>-<NUM>,. , and an N-th capacitor <NUM>-N). The plurality of capacitors may be connected in series to the power supply unit <NUM>. Each of the plurality of capacitors may supply a voltage of a different level to the converter <NUM>. According to an embodiment, since the sum of the voltages of the plurality of capacitors (e.g., the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N) is always maintained as an input voltage, when a voltage is supplied to the converter <NUM> from a capacitor selected through switching of the switch unit <NUM>, a voltage of the selected capacitor is lowered, and a voltage of a capacitor which is not selected is increased, so that energy can be stored.

The controller <NUM> may be connected to each of the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N. The controller <NUM> may determine on/off of the switch unit <NUM> so as to supply a designated input voltage to the converter <NUM>. According to an embodiment, the controller <NUM> may control an input path of the converter <NUM> through the switch unit <NUM> such that a voltage of each of the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N is maintained within a predetermined range.

The switch unit <NUM> may be switched on or off according to a control of the controller <NUM>. The switch unit <NUM> may be turned on/off to selectively supply, to the converter <NUM>, a voltage accumulated in each of the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N of the capacitor unit <NUM>. According to an embodiment, the switch unit <NUM> may include a first switch <NUM>-<NUM>, a second switch <NUM>-<NUM>,. , and an N-th switch <NUM>-N which correspond to the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N, respectively.

The converter <NUM> may be selectively supplied with a voltage from the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N of the capacitor unit <NUM> according to on/off of the switch unit <NUM>. The converter <NUM> may output, to the load <NUM>, a voltage stepped-down below a voltage which is input. According to an embodiment, the converter <NUM> may include a buck converter or a direct current-direct current (DC-DC) converter.

The feedback controller <NUM> may provide a feedback signal to at least one of the converter <NUM> or the switch unit <NUM>, based on a voltage of a terminal of the load <NUM>. According to various embodiments, the feedback controller <NUM> and the load <NUM> are not essential components, and may be selectively configured.

According to an embodiment, at least one of the converter <NUM>, the load <NUM>, and the feedback controller <NUM> may be configured in parallel to the switch unit <NUM>. According to an embodiment, at least one converter <NUM> may be configured in parallel to the switch unit <NUM>.

<FIG> schematically illustrates a configuration of an example of a power conversion device which is not within the scope of the claims. <FIG> illustrates a case in which a voltage of a first capacitor C<NUM> is greater than a voltage of a second capacitor C<NUM> (VC1>VC2) in a power conversion device configured as in <FIG>, which is not within the scope of the claims. <FIG> illustrates a case in which a voltage of a first capacitor C<NUM> is less than a voltage of a second capacitor C<NUM> (VC1<<VC2) in a power conversion device configured as in <FIG>, which is not within the scope of the claims.

Referring to <FIG>, the power conversion device <NUM> may include the power supply unit <NUM>, two capacitors (e.g., a first capacitor C<NUM> and a second capacitor C<NUM>), two switches (e.g., a first switch SW1 and a second switch SW2), and the converter <NUM>.

The first capacitor C<NUM> and the second capacitor C<NUM> may be connected in series to the power supply unit <NUM>.

The first switch SW1 may include a (<NUM>-<NUM>)th switch SW11 and a (<NUM>-<NUM>)th switch SW12 which are connected to both ends of the first capacitor C<NUM>, respectively. The second switch SW2 may include a (<NUM>-<NUM>)th switch SW21 and a (<NUM>-<NUM>)th switch SW22 which are connected to both ends of the second capacitor C<NUM>, respectively.

The converter <NUM> may be connected to each of the first switch SW1 and the second switch SW2.

In a case where a voltage of the first capacitor C<NUM> is greater than a voltage of the second capacitor C<NUM> (VC1>VC2) in the power conversion device <NUM> of <FIG>, the first switch SW1 may be connected. In this case, as illustrated in <FIG>, power supplied through the power supply unit <NUM> may be supplied to the converter <NUM> through the first capacitor C<NUM>.

In a case where a voltage of the first capacitor C<NUM> is less than a voltage of the second capacitor C<NUM> (VC1<VC2) in the power conversion device <NUM> of <FIG>, the second switch SW2 may be connected. In this case, as illustrated in <FIG>, power supplied through the power supply unit <NUM> may be supplied to the converter <NUM> through the second capacitor C<NUM>.

<FIG> illustrates a configuration of another example of a power conversion device which is not within the scope of the claims.

Referring to <FIG>, the power conversion device <NUM> may include two capacitors (e.g., the first capacitor C<NUM> and the second capacitor C<NUM>), two switches (e.g., the first switch SW1 and the second switch SW2), a first diode D1, a second diode D2, and the converter <NUM>.

The first switch SW1 may be connected to the first capacitor C<NUM>. The second switch SW2 may be connected to the second capacitor C<NUM>. Each of the first switch SW1 and the second switch SW2 may include at least one of a metal-oxide semiconductor field-effect-transistor (MOSFET), a field effect transistor (FET), and a transistor (TR).

The first diode D1 may be connected between the first switch SW1 and a contact point between the first capacitor C<NUM> and the second capacitor C<NUM>. An anode of the first diode D1 may be connected to the contact point between the first capacitor C<NUM> and the second capacitor C<NUM>, and a cathode of the first diode may be connected to the first switch SW1.

The second diode D2 may be connected between the second switch SW2 and the contact point between the first capacitor C<NUM> and the second capacitor C<NUM>. A cathode of the second diode D2 may be connected to the contact point between the first capacitor C<NUM> and the second capacitor C<NUM>, and an anode of the second diode may be connected to the second switch SW2.

The converter <NUM> may include a third switch SW3, an inductor Lo, a third capacitor Co, and a third diode D3. The converter <NUM> may be configured as a buck converter. The converter <NUM> may be connected to the first switch SW1 and the second switch SW2.

The third switch SW3 may perform a switching operation of the converter <NUM> for power supplied through the first capacitor C<NUM> or the second capacitor C<NUM> according to on/off of the first switch SW1 and the second switch SW2.

The inductor L<NUM> may be connected to the third switch SW3. The third capacitor C<NUM> may be connected between the inductor Lo and the second switch SW2. The third capacitor Co may be connected to the inductor Lo. The inductor Lo and the third capacitor Co may accumulate a charge supplied through the first capacitor C<NUM> or the second capacitor C<NUM> according to a switching operation of the third switch SW3.

A cathode of the third diode D3 may be connected to the third switch SW3, and an anode of the third diode may be connected to the second switch SW2. The third diode D3 may be connected to the third switch SW3. The third diode D3 may form a loop between the inductor L<NUM> and the third capacitor C<NUM> according to the switching operation of the third switch SW3.

At least one converter <NUM> may be connected in parallel to the first switch SW1 or the second switch SW2.

<FIG> illustrates a case in which a voltage of a first capacitor C<NUM> is greater than a voltage of a second capacitor C<NUM> (VC1>VC2) in a power conversion device configured as in <FIG>, which is not within the scope of the claims. <FIG> illustrates a case in which a voltage of a first capacitor C<NUM> is less than a voltage of a second capacitor C<NUM> (VC1<<VC2) in a power conversion device configured as in <FIG>, which is not within the scope of the claims.

Referring to <FIG>, in the power conversion device <NUM>, in a case where a voltage of the first capacitor C<NUM> is greater than a voltage of the second capacitor C<NUM> (VC1>VC2), the first switch SW1 may be turned on and the second switch SW2 may be turned off. In this case, as the third switch SW3 is turned on, the voltage accumulated in the first capacitor C<NUM> may be supplied to the converter <NUM>.

When the first switch SW1 and the third switch SW3 are turned on, a loop may be formed between the inductor L<NUM>, the third capacitor C<NUM>, the second diode D2, and the first capacitor C<NUM>.

Referring to <FIG>, in the power conversion device <NUM>, in a case where a voltage of the first capacitor C<NUM> is less than a voltage of the second capacitor C<NUM> (VC1<VC2), the first switch SW1 may be turned off and the second switch SW2 may be turned on. In this case, as the third switch SW3 is turned on, the voltage accumulated in the second capacitor C<NUM> may be supplied to the converter <NUM>.

When the second switch SW2 and the third switch SW3 are turned on, a loop may be formed between the first diode D1, the inductor L<NUM>, the third capacitor C<NUM>, and the second capacitor C<NUM>.

In the power conversion device <NUM> illustrated in <FIG> and <FIG>, when the third switch SW3 is turned on, an electric current may flow through the inductor L<NUM>, and a charge may be accumulated in the inductor L<NUM> and the third capacitor C<NUM>. In this case, a cathode-side voltage of the third diode D3 becomes larger than an anode-side voltage thereof, so that no electric current may flow through the third diode D3.

<FIG> illustrates a configuration of another example of a power conversion device according to various embodiments of the disclosure.

Referring to <FIG>, in the power conversion device <NUM> according to various embodiments of the disclosure, a short-circuiting may occur, according to a power path configuration by one of the plurality of capacitors (e.g., the first capacitor C<NUM> to the N-th capacitor CN), in the other switches (e.g., a second switch SW2-<NUM> to a (N-<NUM>)th switch SWN-<NUM>) except for the first switch SW1 and the N-th switch SWN. Therefore, reverse diodes D may be connected to the other switches (e.g., the second switch SW2-<NUM> to the (N-<NUM>)th switch SWN-<NUM>) except for the first switch SW1 and the N-th switch SWN, respectively.

Referring to <FIG>, the power conversion device <NUM> may have a configuration which does not include the third switch SW3 in the converter <NUM> illustrated in <FIG>.

In the power conversion device <NUM> illustrated in <FIG>, in a case where a voltage of the first capacitor C<NUM> is greater than a voltage of the second capacitor C<NUM> (VC1>VC2), the first switch SW1 may be turned on and the second switch SW2 may be turned off. In this case, the voltage supplied through the first capacitor C<NUM> may be applied to the converter <NUM> through the first switch SW1.

In the power conversion device <NUM> illustrated in <FIG>, in a case where a voltage of the first capacitor C<NUM> is less than a voltage of the second capacitor C<NUM> (VC1<<VC2), the first switch SW1 may be turned off and the second switch SW2 may be turned on. In this case, the voltage supplied may be applied to the converter <NUM> through the second capacitor C<NUM> and the second switch SW2.

Referring to <FIG>, the power conversion device <NUM> according to various embodiments of the disclosure may have a configuration which does not include the third switch SW3 in the converter <NUM> illustrated in <FIG>.

In the power conversion device <NUM> illustrated in <FIG>, a short-circuiting may occur, according to a power path configuration by one of the plurality of capacitors (e.g., the first capacitor C<NUM> to the N-th capacitor CN), in the other switches (e.g., the second switch SW2-<NUM> to the (N-<NUM>)th switch SWN-<NUM>) except for the first switch SW1 and the N-th switch SWN. Therefore, reverse diodes D may be connected to the other switches (e.g., the second switch SW2-<NUM> to the (N-<NUM>)th switch SWN-<NUM>) except for the first switch SW1 and the N-th switch SWN, respectively. A reverse diode D may not be connected to a part of the other switches (e.g., the second switch SW2-<NUM> to the (N-<NUM>)th switch SWN-<NUM>).

<FIG> is a flowchart illustrating an example of a power conversion method according to various embodiments of the disclosure.

Operations <NUM> to <NUM> of <FIG> may be performed by, for example, the processor <NUM> of <FIG> or the controller <NUM> of the power conversion device <NUM> of <FIG>. The components of <FIG> may be used for the description of the operations <NUM> to <NUM>. The operations <NUM> to <NUM> may be implemented by instructions which can be performed by the controller <NUM> of the power conversion device <NUM>.

In operation <NUM>, the controller <NUM> may determine an input voltage required for the converter <NUM>.

In operation <NUM>, the controller <NUM> may determine at least a part of the plurality of capacitors (e.g., the first capacitor <NUM>-<NUM>, the second capacitor <NUM>-<NUM>,. , and the N-th capacitor <NUM>-N) included in the power conversion device <NUM>, in order to supply a voltage required for the converter <NUM>. For example, the at least a part of the capacitors may be a minimum number of capacitors for supplying a voltage required for the converter <NUM>.

In operation <NUM>, the controller <NUM> may select a capacitor which satisfies a specified voltage (e.g., the highest voltage), among the determined at least a part of the capacitors, in order to supply a voltage required for the converter <NUM>.

In operation <NUM>, the controller <NUM> may set a power path for supplying power to the converter <NUM> with respect to a capacitor selected through the switch unit <NUM>.

In operation <NUM>, the controller <NUM> may supply power to the converter <NUM> by using a switch (e.g., one of the first switch <NUM>-<NUM>, the second switch <NUM>-<NUM>,. , and the N-th switch <NUM>-N) which is turned on according to the setting of the power path.

<FIG> illustrates a comparison of switching loss between a conventional power conversion device and a power conversion device which is not within the scope of the claims.

<FIG> shows schematic analysis of a switching loss reduction level, that is, a level of reducing inductance of the inductor L<NUM> of the converter <NUM> in the cases of applying the power conversion device <NUM> to an application of dropping an input voltage of a lithium ion battery from about <NUM>. 7V to about 1V and an application of dropping an input voltage through a charger, to which a fast charging technology is applied, from about 5V∼20V to about <NUM>.

Referring to <FIG>, when the power conversion device <NUM> and the power conversion method are used, in a case of stepping down from about <NUM>. 7V to about 1V, compared to the conventional method, the inductance can be lowered to about <NUM>% as in P1. In addition, in the cases of stepping down from about 9V to about <NUM>. 7V and stepping down from about 20V to about <NUM>. 7V, the inductance can be lowered to about <NUM>% as in P2 and P3. When the power conversion device <NUM> and the power conversion method are used, an input voltage of the converter <NUM> can be lowered to less than half, and thus switching loss can be lowered to at least about <NUM>/<NUM> or less.

Claim 1:
A power conversion device (<NUM>) comprising:
a converter (<NUM>);
a capacitor unit (<NUM>) comprising a plurality of at least three capacitors (<NUM>-<NUM>, <NUM>-<NUM>, ..., <NUM>-N) for accumulating an input voltage which is input thereto, wherein the plurality of capacitors (<NUM>-<NUM>, <NUM>-<NUM>, ..., <NUM>-N) are connected in series, each of the plurality of capacitors (<NUM>-<NUM>, <NUM>-<NUM>, ..., <NUM>-N) being configured to supply a voltage of a different level to the converter;
a switch unit (<NUM>) connected to the capacitor unit and comprising a plurality of switches (<NUM>-<NUM>, <NUM>-<NUM>, ..., <NUM>-N) for selectively connecting one capacitor among the plurality of capacitors to the converter, wherein the switch unit further comprises reverse diodes (D) connected in series to the other switches except for a first switch (SW1) and a N-th switch (SWN) among the plurality of switches, respectively;
a controller (<NUM>) connected to the capacitor unit and the switch unit,
wherein the controller (<NUM>) is configured to
- determine a capacitor having a largest accumulated voltage, among the plurality of capacitors, as the capacitor satisfying a specified condition,
- set two switches among the plurality of switches, to be turned on, the two switches corresponding to the capacitor,
- set the other switches except for the two switches among the plurality of switches, to be turned off, so that the capacitor and the converter are electrically connected and the voltage accumulated in the capacitor is supplied to the converter;
wherein the power conversion device (<NUM>) further comprises:
a load (<NUM>) electrically connected to the converter (<NUM>); and
a feedback controller (<NUM>) configured to provide a feedback signal to the converter,
based on an input voltage of the load.