KR20180067071A - Vehicle and DC-DC Converter for Vehicle - Google Patents

Abstract

The present invention is to provide a vehicle including a DC-DC converter and a DC-DC converter for a vehicle, capable of reducing a withstanding voltage of a switching device. The vehicle includes: a first battery for outputting power of a first voltage; a second battery for outputting a power of a second voltage; and a DC-DC converter that converts the first voltage of the first battery into the second voltage, and supplies the converted second voltage to the second battery. The DC-DC converter includes: a first conversion circuit having a first output capacitor for outputting a third voltage, a first drive switch for controlling a first current output from the first battery, and a first output inductor to prevent a sudden change in the first current; a second conversion circuit having a second output capacitor for outputting a second voltage, a transformer for converting the third voltage to the second voltage, a second drive switch for controlling a second current input to the transformer, and a plurality of diodes for rectifying the current and outputting the rectified current to the second output capacitor; and a controller for controlling the opening and closing of the first drive switch in accordance with the first voltage and the second voltage.

Description

≪ Desc / Clms Page number 1 > Vehicle & DC-DC Converter for Vehicle &

The disclosed invention relates to a DC-DC converter for a vehicle and a vehicle, and more particularly to a DC-DC converter for a vehicle and a vehicle including a plurality of batteries.

Generally, a vehicle means a moving means or a transportation means that travels on a road or a line using fossil fuel, electricity, or the like as a power source.

Vehicles using fossil fuels can emit fine dust, water vapor, carbon dioxide, carbon monoxide, hydrocarbons, nitrogen, nitrogen oxides, and / or sulfur oxides due to the combustion of fossil fuels. Water vapor and carbon dioxide are known to cause global warming, and fine dust, carbon monoxide, hydrocarbons, nitrogen oxides, and / or sulfur oxides are known as air pollutants that can harm people.

For this reason, vehicles using environmentally friendly energy that replace fossil fuels are being developed recently. For example, Hybrid Electric Vehicle (HEV) and Electric Vehicle (EV) that use both fossil fuel and electricity are being developed.

Hybrid cars and electric cars have separate high-voltage batteries that power the motor that drives the vehicle and low-voltage batteries that power the vehicle's electrical components. In addition, hybrid cars and electric vehicles generally include a converter that converts the voltage of the high-voltage battery to the voltage of the low-voltage battery to supply power from the high-voltage battery to the low-voltage battery.

One aspect of the disclosed invention is to provide a DC / DC converter for a vehicle and a vehicle that includes a DC-DC converter capable of reducing the internal pressure of a switching device.

According to an aspect of the disclosed subject matter, a vehicle includes: a first battery that outputs power of a first voltage; A second battery for outputting a power of a second voltage; And a DC-DC converter that converts the first voltage of the first battery to the second voltage and supplies the converted second voltage to the second battery, wherein the DC-DC converter converts the third voltage A first conversion circuit including a first output capacitor for outputting a first current, a first drive switch for controlling a first current outputted from the first battery, and a first output inductor for preventing a sudden change of the first current; A second output switch for outputting the second voltage; a transformer for converting the third voltage to the second voltage; a second drive switch for controlling a second current input to the transformer; A second conversion circuit including a plurality of diodes rectifying the current and outputting the current to the second output capacitor; And a controller for controlling the opening and closing of the first driving switch according to the first voltage and the second voltage.

The DC-DC converter may further include a pulse generation circuit for opening / closing the second drive switch according to a predetermined reference duty ratio.

The controller may calculate the duty ratio of the first drive switch from the first voltage, the second voltage, and the reference duty ratio.

The controller may output a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch.

The controller may further control opening and closing of the second drive switch in accordance with the first voltage and the second voltage.

The controller may calculate the third voltage from the first voltage and the second voltage.

The controller may calculate a duty ratio of the first driving switch and a duty ratio of the second driving switch from the first voltage, the second voltage, and the third voltage.

Wherein the controller outputs a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch and for turning the second driving switch on or off according to a duty ratio of the second driving switch, And can output a second switching signal that turns off.

According to another aspect of the disclosed subject matter, a DC-DC converter for a vehicle includes a DC-DC converter for converting a first voltage output from a first battery to a second voltage output from a second battery, A first output capacitor connected between the first output capacitor and the first output capacitor and having a first output capacitor coupled to the first output capacitor and a first output inductor coupled between the anode of the first battery and the first output capacitor to control a first current output from the first battery, A first conversion circuit including a drive switch; A second output capacitor connected to the first conversion circuit to receive the third voltage and a secondary coil connected to the second battery to output the second voltage; A second drive switch connected in series with the transformer for controlling a second current input to the transformer and a plurality of diodes for rectifying the current output from the transformer and outputting the rectified current to the second output capacitor, A second conversion circuit comprising; And a controller for controlling the opening and closing of the first driving switch according to the first voltage and the second voltage.

The vehicle DC-DC converter may further include a pulse generation circuit for opening / closing the second drive switch in accordance with a predetermined reference duty ratio.

The controller may calculate the duty ratio of the first drive switch from the first voltage, the second voltage, and the reference duty ratio.

The controller may output a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch.

The controller may further control opening and closing of the second drive switch in accordance with the first voltage and the second voltage.

The controller may calculate the third voltage from the first voltage and the second voltage.

The controller may calculate a duty ratio of the first driving switch and a duty ratio of the second driving switch from the first voltage, the second voltage, and the third voltage.

Wherein the controller outputs a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch and for turning the second driving switch on or off according to a duty ratio of the second driving switch, And can output a second switching signal that turns off.

According to an aspect of the disclosed invention, it is possible to provide a DC / DC converter for a vehicle and a vehicle including a DC-DC converter capable of reducing the internal pressure of a switching element.

1 shows a vehicle body of a vehicle according to an embodiment.
Fig. 2 shows a vehicle undercarriage according to one embodiment.
Fig. 3 shows electrical components of a vehicle according to an embodiment.
4 shows a power system of a vehicle according to one embodiment.
5 shows a configuration of a DC-DC converter according to an embodiment.
Fig. 6 shows the operation of the DC-DC converter shown in Fig.
FIG. 7 shows a configuration of a DC-DC converter according to another embodiment.
FIG. 8 shows the configuration of a DC-DC converter according to another embodiment.
FIG. 9 shows the operation of the DC-DC converter shown in FIG.

Like reference numerals refer to like elements throughout the specification. This specification does not describe all the elements of the embodiments, and duplicate descriptions of the contents or embodiments in the technical field to which the disclosed invention belongs are omitted. The term 'part, module, member, or block' used in the specification may be embodied in software or hardware, and a plurality of 'part, module, member, and block' may be embodied as one component, It is also possible that a single 'part, module, member, block' includes a plurality of components.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only the case directly connected but also the case where the connection is indirectly connected, and the indirect connection includes connection through the wireless communication network do.

Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

Throughout the specification, when a member is located on another member, it includes not only when a member is in contact with another member but also when another member exists between the two members.

The terms first, second, etc. are used to distinguish one element from another, and the elements are not limited by the above-mentioned terms.

The singular forms " a " include plural referents unless the context clearly dictates otherwise.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of the steps, and each step may be performed differently from the stated order unless clearly specified in the context. have.

Hereinafter, the working principle and embodiments of the disclosed invention will be described with reference to the accompanying drawings.

The vehicle 1 is a mechanical / electric device for transporting people and / or objects using the rotational force of the internal combustion engine and / or the rotational force of the electric motor.

The vehicle 1 using the internal combustion engine can explosively burn fossil fuels such as gasoline, light oil and gas, convert the translational force generated during the combustion of the fossil fuel into rotational force, and move using the converted rotational force.

A vehicle 1 using an electric motor is called an electric vehicle (EV), and can convert electric energy stored in a battery into rotational kinetic energy, and can move using the converted rotational force.

There is also a vehicle 1 using an internal combustion engine and an electric motor. Such a vehicle 1 is called a hybrid electric vehicle (HEV) and can be moved not only by using an internal combustion engine but also by using an electric motor. A hybrid vehicle is a general hybrid vehicle that receives only fossil fuel from the outside and generates electric energy using internal combustion engines and electric motors (generators), and a plug-in hybrid vehicle -in Hybrid Electric Vehicle (PHEV).

Electric vehicles and hybrid vehicles generally include a battery for supplying electric energy to the drive motor and a battery for supplying electric energy to the electric device (electric field, electric device) of the vehicle 1, respectively. For example, a battery that supplies electrical energy to a drive motor may have an output voltage of approximately several hundred volts (V), and a battery that supplies electrical electrical energy to electrical components may have an output strategy of approximately tens of volts.

Further, the electric vehicle charges the battery for the drive motor from the external power source, and converts the voltage of the battery for the drive motor to charge the battery for the electric component. The hybrid vehicle also uses an internal combustion engine to charge the battery for the drive motor, and converts the voltage of the battery for the drive motor to charge the battery for the electric component.

Accordingly, the electric vehicle and the hybrid vehicle may include a DC-DC converter for converting a voltage of several hundreds of volts output from the battery for the drive motor to a voltage of several tens of volts for charging the battery for the electric component.

Hereinafter, the DC-DC converter included in the vehicle 1 and the vehicle 1 will be described in detail.

1 shows a vehicle body of a vehicle according to an embodiment. Fig. 2 shows a vehicle undercarriage according to one embodiment. Fig. 3 shows electrical components of a vehicle according to an embodiment. 4 also shows a power system of a vehicle according to one embodiment.

1, 2, 3 and 4, a vehicle 1 includes a body 10 which forms an appearance of a vehicle 1 and accommodates a driver and / or a baggage, a body 10, A chassis 20 including other power generation devices, a power transmission device, a braking device, a steering device, a wheel, etc., and an electric component 30 that protects the driver and provides convenience to the driver.

As shown in Fig. 1, the vehicle body 20 forms an interior space in which the driver can stay, an internal combustion engine room for accommodating the internal combustion engine, and a trunk room for accommodating the cargo.

The vehicle body 20 includes a hood 21, a front fender 22, a roof panel 23, a door 24, a trunk lid 25, A quarter panel 26, and the like. A front window 27 is provided in front of the vehicle body 20 and a side window 28 is provided on a side surface of the vehicle body 20, A rear window 29 may be provided at the rear of the vehicle body 20.

2, the undercarriage 20 includes a power generation device 21, a power transmission device 22, a steering device (not shown) for driving the vehicle 1 under the control of the driver and / 23, a braking device 24, a wheel 25, and the like. The undercarriage 20 may further include a frame 26 for fixing the power generating device 21, the power transmitting device 22, the steering device 23, the braking device 24, and the wheel 25 .

The power generation device 21 generates a rotational force for traveling the vehicle 1 and may include an internal combustion engine 21a, a fuel supply device, an exhaust device, an electric motor 21b, a first battery B1, .

The power transmitting device 22 transmits the rotational force generated by the power generating device 21 to the wheels 25 and includes a clutch / transmission 22a, a shift lever, a transmission, a differential device, a drive shaft 22b, .

The steering device 23 controls the running direction of the vehicle 1 and may include a steering wheel 23a, a steering gear 23b, a steering link 23c, and the like.

The braking device 24 stops the rotation of the wheel 25 and may include a brake pedal, a master cylinder, a brake disk 24a, a brake pad 24b, and the like.

The wheel 25 receives rotational force from the power generating device 21 through the power transmitting device 22 and can move the vehicle 1. [ The wheel 25 may include a front wheel provided at the front of the vehicle and a rear wheel provided at the rear of the vehicle.

The vehicle 1 may include various electrical components 30 for the safety and comfort of the driver and passenger, as well as the control of the vehicle 1, as well as the mechanical components described above.

3, the vehicle 1 includes an engine management system 31, a motor control unit 32, a transmission control unit 33, An electronic braking system 34, an electric power steering 35, a navigation device 36, an audio device 37, a heating / ventilation / HVAC < / RTI >

The electrical components 30 may communicate with each other via the vehicle communication network NT. For example, the electrical components 30 may be implemented as Ethernet, MOST (Media Oriented Systems Transport), Flexray, CAN (Controller Area Network), LIN Data can be exchanged through the network.

Also, the electric component parts 30 can be supplied with electric power from the second battery B2.

The second battery B2 may be separately provided from the first battery B1 shown in FIG.

For example, as shown in FIG. 4, the first battery B1 may supply electric power to the electric motor 21b that drives the vehicle 1 and may be supplied with several hundreds of volts (V) to supply electric power to the electric motor 21b. ) (For example, 200 V to 800 V). The second battery B2 can supply electric power to the electric components 30 and can supply electric power to the electric components 30 by applying a voltage of several tens volts (V) (for example, 12V to 24V) Voltage can be output. In other words, the first battery B1 and the second battery B2 may be separately provided to supply power to the electric motor 21b and the electric component 30, which are supplied with different voltages.

In addition, the first battery B1 can supply electric power to the electric motor 21b, and the first battery B1 can be charged by the electric motor 21b.

For example, while the vehicle 1 is descending the descending road, the vehicle 1 can travel by gravity and / or inertia, and the rotational force of the wheel 25 is transmitted to the electric motor 21b ). ≪ / RTI > The electric motor 21b can generate electric energy from the rotational force transmitted from the wheel 25 and the electric energy generated by the electric motor 21b can be stored in the first battery B1.

As another example, when the driver stops the vehicle 1 or decelerates the running speed of the vehicle 1, the electric motor 21b can generate a regenerative braking force for decelerating the vehicle 1 , And generate electrical energy by regenerative braking. The electric energy generated by the electric motor 21b may be stored in the first battery B1.

The first battery B1 can receive electric energy from the electric motor 21b while the second battery B2 can supply electric energy from the first battery B1 through the DC- Can receive.

As described above, the output voltage of the second battery B2 is different from the output voltage of the first battery B1. Therefore, a DC-DC converter 100 capable of converting the output voltage of the first battery B1 to the output voltage of the second battery B2 for charging the second battery B2 may be provided.

DC-DC converter 100 may convert the first voltage output from the first battery B1 to the second voltage of the second battery B2. The electrical energy of the second voltage converted by the DC-DC converter 100 may be stored in the second battery B2.

The configuration and operation of the DC-DC converter 100 will be described below.

5 shows a configuration of a DC-DC converter according to an embodiment.

5, the DC-DC converter 100 is provided between the first battery B1 for outputting the first voltage V1 and the second battery B2 for outputting the second voltage V2 And the DC-DC converter 100 may receive the first voltage V1 and output the second voltage V2.

The DC-DC converter 100 includes a first conversion circuit 110, a second conversion circuit 120, a pulse generation circuit 130, an input voltage sensor 140, an output voltage sensor 150, Controller 160 may be included.

The first conversion circuit 110 receives the first voltage V1 from the first battery B1 and converts the first voltage V1 to the third voltage V3, 2 conversion circuit 120 in accordance with the present invention.

The first conversion circuit 110 may have the form of a buck converter and includes a first drive switch Q1, a first diode D1, a first output inductor Lo1, And may include a capacitor Co1.

The first drive switch Q1 may be connected to the anode of the first battery B1 and may be connected to the first output inductor Lo1 and the first output B1 from the first battery B1 according to the first switching signal of the controller 160. [ It is possible to allow or block the current to the capacitor Co1.

Specifically, when the first drive switch Q1 is closed (turned on), a current flows from the first battery B1 to the first output inductor Lo1 and the first output capacitor Co1, The current can be cut off from the first battery B1 to the first output inductor Lo1 and the first output capacitor Co1. As described above, when the first drive switch Q1 is repeatedly opened and closed, alternating current can be supplied to the first output inductor Lo1 and the first output capacitor Co1.

The first drive switch Q1 may have various structures and materials. For example, the first drive switch Q1 may be a bipolar junction transistor (BJT), a metal-oxide-semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor, IGBT) or the like can be employed. Also, the first drive switch Q1 may be composed of a semiconductor material such as silicon (Si), silicon carbide (SiC), or gallium arsenide (GaAs).

The first drive switch Q1 may be provided with a first reflux diode Dq1 for protecting the first drive switch Q1 from the reverse voltage due to the inductance of the first output inductor Lo1. The first feedback diode D1 may be formed by the physical structure of the first drive switch Q1 or may be provided separately and may be connected to both ends of the first drive switch Q1 (for example, emitter and collector, .

The first diode D1 may be connected to the cathode of the first battery B1 and the first drive switch Q1. Specifically, the cathode of the first diode D1 is connected to the first drive switch Q1, and the anode of the first diode D1 is connected to the cathode of the first battery B1 .

The first diode D1 cuts off the current of the first battery B1 while the first drive switch Q1 is turned on and turns on the first output inductor Lo1 while the first drive switch Q1 is turned off Can be tolerated.

The first output inductor Lo1 and the first output capacitor Co1 may be connected in series between the cathode and the anode of the first diode D1. Specifically, the first output inductor Lo1 and the first output capacitor Co1 are connected in series to each other, the first output inductor Lo1 is connected to the first drive switch Q1, the first output capacitor Co1 May be connected to the cathode of the first battery B1. Further, the voltage across the first output capacitor Co1 may be output to the second conversion circuit 120. [

The first output inductor Lo1 and the first output capacitor Co1 filter out the ripple of the output voltage due to the opening and closing (switching) of the first drive switch Q1, 3 voltage (V3). Specifically, the first output inductor Lo1 prevents a sudden change in current due to the opening / closing (switching) of the first driving switch Q1, and the first output capacitor Co1 prevents switching of the first driving switch Q1 It is possible to prevent a sudden change in voltage due to switching (switching).

With respect to the operation of the first conversion circuit 110, when the first drive switch Q1 is turned on, the current of the first battery V1 flows through the first drive switch Q1 and the first output inductor Lo1, Can be supplied to the output capacitor Co1. At this time, magnetic energy due to the current can be stored in the first output inductor Lo1.

When the first drive switch Q1 is turned off, the supply of the current from the first battery V1 to the first output capacitor Co1 is interrupted, and the current due to the magnetic energy of the first output inductor Lo1 flows into the first Can be supplied to the output capacitor Co1. The current of the first output inductor Lo1 can pass through the first diode D1.

By this operation, the first conversion circuit 110 can convert the first voltage V1 to the third voltage V3. The relationship between the first voltage V1 and the third voltage V3 is expressed by Equation (1).

[Equation 1]

Here, V3 represents the value of the third voltage, Duty1 represents the first duty ratio of the first drive switch, and V1 represents the value of the first voltage.

The first duty ratio Duty1 of the first drive switch Q1 represents a ratio of the on time of the first drive switch Q1 to the first drive switch Q1. Therefore, the first duty ratio Duty1 of the first drive switch Q1 has a value between 0 and 1.

As a result, the third voltage V3 is smaller than the first voltage V1, and the first conversion circuit 110 can drop the voltage.

The second conversion circuit 120 receives the third voltage V3 from the first conversion circuit 110 and converts the third voltage V3 into the second voltage V2 and outputs the second voltage V2 And output to the second battery B2.

The second conversion circuit 120 may have the form of a forward converter and includes a transformer 121, a second drive switch Q2, a reset capacitor Cr, a reset switch Q3, And may include first and second diodes D1 and D2, a second output inductor Lo2, and a second output capacitor Co2.

The transformer 121 can change the value of the alternating voltage and / or the value of the alternating current by using the electromagnetic induction phenomenon.

The transformer 121 may include an input-side primary coil L1, an output-side secondary coil L2, and an iron core for transmitting a magnetic field from the primary coil L1 to the secondary coil L2. have. A magnetic field that changes with time is generated in the iron core by the AC voltage and the AC current input to the primary coil L1 and an AC voltage and an AC current can be generated in the secondary coil L2 by the magnetic field of the iron core .

The output voltage output by the secondary coil L2 can be calculated by Equation (2).

&Quot; (2) "

Here, Vout represents the output voltage of the secondary coil, Vin represents the input voltage of the primary coil, N2 represents the number of turns of the secondary coil, and N1 represents the number of turns of the primary coil.

The output voltage Vout of the secondary coil L2 is set to the second voltage Vout of the input voltage Vin of the primary coil L1 and the number of turns N1 of the primary coil L1 May be proportional to the ratio of the number of turns (N2) of the coil (L2).

The ideal transformer assumes that the input power (voltage and current) and output power are the same, but the actual transformer has different input power and output power due to loss of iron core and so on. The loss of this actual transformer can be expressed as a leakage inductance. Also, for more accurate modeling, the transformer 121 may further include a leakage inductor L3 that exhibits a leakage inductance.

The ideal transformer assumes that all the magnetic field generated by the primary coil L1 is transferred to the secondary coil L2, but in the actual transformer, some of the magnetic field generated by the primary coil L1 is the primary coil L1. The components remaining in the primary coil L1 can be represented by a magnetizing inductance. Further, for more accurate modeling, the transformer 121 may further include a magnetizing inductor L4 indicating magnetizing inductance.

The second drive switch Q2 may be connected in series with the primary coil L1 of the transformer 121 and may control the current so that an alternating current is input to the primary coil L1 of the transformer 120. [

The first conversion circuit 110 described above outputs a DC voltage and a DC current, and the transformer 121 can convert an AC voltage and an AC current. Therefore, the second drive switch Q2 can pass or block the direct current output from the first conversion circuit 110 so that the alternating current is input to the transformer 121. [

Specifically, the second drive switch Q2 can be repeated to pass the current from the first converter circuit 110 to the transformer 120 and to shut off the current from the first converter circuit 110 to the transformer 120 have. In other words, the second drive switch Q2 can repeat the passage of the current and interruption of the current at a very high speed (for example, several hundred kHz). The current to be converted in time, that is, the alternating current, can be inputted to the transformer 121 by the switching operation of the second drive switch Q2.

The second drive switch Q2 may have various structures and materials. For example, the second drive switch Q2 may employ a bipolar junction transistor, a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, or the like. The second drive switch Q2 may be made of a semiconductor material such as silicon (Si), silicon carbide (SiC), or gallium arsenide (GaAs).

The second drive switch Q2 may be provided with a second return diode Dq2 for protecting the second drive switch Q2 from the reverse voltage due to the inductance of the primary coil L1 of the transformer 121. [ The second feedback diode Dq2 may be generated by the physical structure of the second drive switch Q2 or may be provided separately and may be connected to both ends of the second drive switch Q2 (for example, emitter and collector, .

The reset capacitor Cr may be connected in parallel with the transformer 121 and may emit magnetic energy stored in the magnetizing inductor L4 of the transformer 121. [ The magnetic field which is not transferred to the secondary coil L2 of the transformer 121 and remains in the primary coil L1 is represented by the magnetizing inductor L4 and the reset circuit 140 is connected to the magnetizing inductor (That is, the current) stored in the memory cells L4 and L4. By the accumulated magnetic energy, the magnetizing inductor L4 can generate a current, and the reset capacitor Cr can store the current of the magnetizing inductor L4 as electric energy.

The reset switch Q3 is connected in series with the reset capacitor Cr and the reset switch Q3 and the reset capacitor Cr can be connected in parallel with the transformer 121. [

The reset switch Q3 can control the current for discharging the magnetic energy stored in the magnetizing inductor L4. In other words, according to the operation of the reset switch Q3, the magnetic energy stored in the magnetization inductor L4 of the transformer 121 may be released to the reset capacitor Cr or the emission of magnetic energy may be cut off.

The reset switch Q3 may have various structures and materials. For example, the reset switch Q3 may employ a bipolar junction transistor, a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, or the like. The reset switch Q3 may be made of a semiconductor material such as silicon (Si), silicon carbide (SiC), or gallium arsenide (GaAs).

The reset switch Q3 may be provided with a third return diode Dq3 for protecting the reset switch Q3 from the reverse voltage due to the inductance of the primary coil L1 of the transformer 121. [ The third reflux diode Dq3 may be created or provided separately by the physical structure of the reset switch Q3 and may be provided between both ends of the reset switch Q3 (for example, emitter and collector, source and drain) do.

The second diode D2 and the third diode D3 may be connected to both ends of the secondary coil L2 of the transformer 121, respectively. Specifically, the anode of the second diode D2 may be connected to one end of the secondary coil L2, and the anode of the third diode D3 may be connected to the other end of the secondary coil L2. The cathode of the second diode D2 and the cathode of the third diode D3 may be connected to the second output inductor Lo2.

The second diode D2 and the third diode D3 can convert the alternating current and the alternating current output from the secondary coil L2 of the transformer 121 into a direct current and a direct current, To the second output inductor Lo2 and the second output capacitor Co2.

Specifically, the second diode D2 can supply a positive current outputted by the secondary coil L2 to the second output inductor Lo2 and the second output capacitor Co2. In addition, the second diode D2 can cut off the negative current output from the secondary coil L2.

The third diode D3 interrupts the current of the secondary coil L2 while the second diode D2 passes the positive current of the secondary coil L2 and the second diode D2 interrupts the current of the secondary coil L2, Lt; RTI ID = 0.0 > Lo2 < / RTI > while interrupting the negative current of the second output inductor Lo.

As such, the second / third diode D3 can deliver a positive current to the second output inductor Lo2 and the second output capacitor Co2 during the positive and negative currents output by the transformer 121 . In other words, the second / third diode D3 can rectify the alternating current output from the transformer 121. [

The second output inductor Lo2 and the second output capacitor Co2 may be connected in series between the cathode and the anode of the third diode D3. Specifically, the second output inductor Lo2 and the second output capacitor Co2 are connected to each other in series, the second output inductor Lo2 is connected to the second diode D2, the second output capacitor Co2, May be connected to the cathode of the second battery B2. Also, the voltage across the second output capacitor Co2 can be output to the second battery B2.

The second output inductor Lo1 and the second output capacitor Co1 filter out the ripple of the voltage rectified by the second and third diodes D2 and D3 and apply a DC voltage of a certain magnitude, 2 voltage (V2).

With respect to the operation of the second conversion circuit 120, the second drive switch Q2 and the reset switch Q3 can be turned on / off alternately. In other words, the reset switch Q3 is turned off while the second drive switch Q2 is turned on, and the reset switch Q3 can be turned on while the second drive switch Q2 is turned off.

A positive current can be supplied from the first converter circuit 110 to the primary coil L1 of the transformer 120 when the second drive switch Q2 is turned on and the reset switch Q3 is turned off. The secondary coil L2 of the transformer 120 outputs a positive current due to the positive current of the primary coil L1 of the transformer 120 and the positive current of the secondary coil L2 2 diode D2 and the second output inductor Lo2 to the second output capacitor Co2. At this time, magnetic energy due to the current can be stored in the first output inductor Lo1.

A negative current may be supplied from the reset capacitor Cr to the primary coil L1 of the transformer 120 when the second drive switch Q2 is turned off and the reset switch Q3 is turned on. The secondary coil L2 of the transformer 120 outputs a negative current due to the negative current of the primary coil L1 of the transformer 120 and the negative current of the secondary coil L2 2 diode. At this time, a current due to the magnetic energy of the second output inductor Lo2 can be supplied to the second output capacitor Co2.

By this operation, the second conversion circuit 120 can convert the third voltage V3 to the second voltage V2. The relationship between the third voltage V3 and the second voltage V2 is expressed by Equation (3).

&Quot; (3) "

V2 represents the value of the second voltage, N2 represents the number of turns of the secondary coil, N1 represents the number of turns of the primary coil, represents the second duty ratio of the second drive switch, Represents the value of the third voltage.

At this time, the second duty ratio Duty2 of the second drive switch Q1 has a value between 0 and 1, and N2 / N1 may have a value less than 1 or 1. As a result, the second voltage V2 is smaller than the third voltage V3, and the second conversion circuit 120 can drop the voltage.

The pulse generation circuit 130 may turn on or off the second drive switch Q2 and the reset switch Q3 of the second conversion circuit 120. [ Specifically, the pulse generating circuit 130 may turn on or off the second drive switch Q2 according to a predetermined open / close frequency and a predetermined second duty ratio Duty2, The reset switch Q3 can be turned off or turned on in accordance with turn-on or turn-off.

The pulse generating circuit 130 includes a pulse generator 131 for generating a second switching signal for turning on or off the second driving switch Q2 according to a predetermined switching frequency and a predetermined second duty ratio Duty2, And an inverter 132 for outputting an opposite signal (reset signal) of the second switching signal.

The second switching signal of the pulse generator 131 is input to the second drive switch Q2 and the reset signal of the inverter 132 may be input to the reset switch Q3. Therefore, when the second drive switch Q2 is turned on, the reset switch Q3 is turned off, and when the second drive switch Q2 is turned off, the reset switch Q3 can be turned on.

The voltage drop ratio of the second conversion circuit 120 is fixed because the pulse generation circuit 130 turns on or off the second drive switch Q2 in accordance with the predetermined second duty ratio Duty2.

The input voltage sensor 140 may measure a first voltage V1 of the first battery B1, that is, a voltage input to the DC-DC converter 100. [ The input voltage sensor 140 may also output an electrical signal corresponding to the value of the first voltage V1 to the controller 160. [

The input voltage sensor 140 may include a voltage divider that distributes the first voltage V1 of the first battery B1 and may output the voltage signal distributed by the voltage divider to the controller 160. [

The first battery B1 may supply electric energy to the electric motor 21b, and the output voltage may vary depending on the amount of stored electric energy. Therefore, in order that the DC-DC converter 100 can output a constant-sized voltage to the second battery B2, which is constant regardless of the variation of the first voltage V1 of the first battery B1, 140 may measure the first voltage V1 of the first battery B1 and output the magnitude of the first voltage V1 to the controller 160. [

The output voltage sensor 150 can measure the second voltage V2 of the second battery B2, that is, the voltage output from the DC-DC converter 100. [ The output voltage sensor 150 may also output an electrical signal corresponding to the value of the second voltage V2 to the controller 160. [

The output voltage sensor 150 may include a voltage divider that distributes the second voltage V2 of the second battery B1 and may output the voltage signal distributed by the voltage divider to the controller 160. [

The second battery B2 can supply electric energy to the electric components 30, and the output voltage can be varied according to the amount of stored electric energy. However, it is preferable that the second voltage V2 of the second battery B2 maintains a certain range in order to stably operate the electric component parts 30 and to prevent the electric component parts 30 from being damaged. Therefore, the output voltage sensor 150 measures the second voltage V2 of the second battery B2 so that the DC-DC converter 100 maintains the output voltage of the second battery B2 constant, 2 < / RTI > voltage V2 to the controller 160. In this case,

The controller 160 may control the operation of the DC-DC converter 100 and may include a memory 161 and a processor 162 for controlling the DC-DC converter 100.

The memory 161 may store a control program and control data for controlling the operation of the DC-DC converter 100. Also, the memory 161 may temporarily store the value of the first voltage V1 and the value of the second voltage V2.

The memory 161 may also provide the control program and / or control data to the processor 162 in accordance with the memory control signal of the processor 162 or may provide a value of the first voltage V1 and a value of the second voltage V2 To the processor 162.

The memory 161 may include a volatile memory such as a Static Random Access Memory (S-RAM) or a Dynamic Random Access Memory (DRAM), which can temporarily store data. In addition, the memory 161 may include a read only memory, an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or the like, which can store control programs and / , Flash memory, and the like.

The processor 162 may include various logic and arithmetic circuits and may process data according to a program provided from the memory 162 and generate control signals according to the processing results.

For example, the processor 162 may calculate the first duty ratio Duty1 of the first drive switch Q1 from the value of the first voltage V1 and the value of the second voltage V2. The processor 162 also turns on or off the first drive count position Q1 according to a predetermined switching cycle of the first drive switch Q1 and the first duty ratio Duty1 of the first drive switch Q1, The first switching signal can be generated.

The memory 161 and the processor 162 may be implemented as separate integrated circuits (ICs), or the memory 161 and the processor 162 may be integrated into one integrated circuit.

In this way, the controller 160 can control the opening and closing operations of the first driving switch Q1 based on the value of the first voltage V1 and the value of the second voltage V2. In addition, the controller 160 can start or stop the pulse generating circuit 130 based on the value of the first voltage V1 and the value of the second voltage V2.

As described above, the second drive switch Q2 of the second conversion circuit 120 is turned on or off by the second switching signal having the fixed second duty ratio Duty2, and the second conversion circuit 120 ) Is fixed.

Therefore, in order to change the voltage drop ratio of the first conversion circuit 110, the controller 160 selects the first voltage V1 of the first drive switch Q2 from the value of the first voltage V1 and the value of the second voltage V2, It is possible to calculate the duty ratio Duty1 and control the opening / closing of the first drive switch Q2 according to the first duty ratio Duty1.

As a result, the voltage drop ratio of the DC-DC converter 100 as a whole is changed, and the second voltage V2 is applied to the second battery V2 at a constant second voltage (V1) in spite of the change in the first voltage V1 of the first battery V2).

Specifically, the relationship between the value of the first voltage V1 and the value of the second voltage V2 can be expressed by Equation (4).

&Quot; (4) "

V2 represents the value of the second voltage, N2 represents the number of turns of the secondary coil, N1 represents the number of turns of the primary coil, represents the second duty ratio of the second drive switch, 1 duty ratio, and V1 represents the value of the first voltage.

The number of turns N2 of the secondary coil L2, the number of turns N1 of the primary coil L1 and the second duty ratio Duty2 can be fixed in Equation (4). Accordingly, the controller 160 sets the first duty ratio Duty1 to the first voltage V1 according to the value of the first voltage V1 and the second voltage V2 to convert the first voltage V1 to the second voltage V2, Can be adjusted.

As described above, by connecting the first conversion circuit 110 and the second conversion circuit 120 in sequence, the DC-DC converter 100 can be realized by the first conversion circuit 110 and the second conversion circuit 120, A further improved voltage drop effect can be obtained.

In addition, by sequentially connecting the first conversion circuit 110 and the second conversion circuit 120, the internal pressure of the switches Q1, Q2, and Q3 can be lowered.

When the first converter circuit 110 or the second converter circuit 120 alone converts the first voltage V1 of the first battery B1 to the second voltage V2 of the second battery B2, The voltage applied to the switches Q1, Q2 and Q3 may be twice the first voltage V1 of the first battery B1 to the first voltage V1 of the first battery B1.

For example, when the first voltage V1 of the first battery B1 is 800V and the second voltage V2 of the second battery B2 is 12V and the first conversion circuit 110 is used alone A voltage of approximately 800 V may be applied to the first drive switch Q1 of the first conversion circuit 110 when the first voltage V1 is converted into the second voltage V2.

When the second conversion circuit 110 alone converts the first voltage V1 to the second voltage V2, the voltages of the first voltage V1 and the reset capacitor Cr are applied to the second drive switch Q2, a voltage of approximately 1600V may be applied to the second drive switch Q2 of the second conversion circuit 120. [

On the other hand, when the first conversion circuit 110 and the second conversion circuit 120 together convert the first voltage V1 of the first battery B1 to the second voltage V2 of the second battery B2 , The voltage applied to the switches Q1, Q2 and Q3 may be reduced to half.

For example, when the first voltage V1 of the first battery B1 is 800V, the third voltage V3 is 400V, and the second voltage V2 of the second battery B2 is 12V, A voltage of approximately 400 V may be applied to the first drive switch Q1 of the first conversion circuit 110 and a voltage of approximately 800 V may be applied to the second drive switch Q2 of the second conversion circuit 120. [

When the first voltage V1 of the first battery B1 is 800V and the third voltage V3 is 260V and the second voltage V2 of the second battery B2 is 12V, A voltage of approximately 540 V may be applied to the first drive switch Q1 of the conversion circuit 110 and a voltage of approximately 520 V may be applied to the second drive switch Q2 of the second conversion circuit 120. [

As described above, by sequentially connecting the first conversion circuit 110 and the second conversion circuit 120, the internal pressure of the second drive switch Q2 of the second conversion circuit 120 can be lowered in particular.

Hereinafter, the operation of the DC-DC converter 100 will be described.

Fig. 6 shows the operation of the DC-DC converter shown in Fig.

6, the voltage drop operation 1000 of the DC-DC converter 100 is described.

The DC-DC converter 100 may perform the voltage drop operation 1000 at predetermined time intervals. For example, the DC-DC converter 100 may perform the voltage drop operation 1000 every cycle of the first drive switch Q1.

DC-DC converter 100 senses the second voltage V2 of the second battery B1 (1010).

The output voltage sensor 150 of the DC-DC converter 100 measures the value of the second voltage V2, that is, the output voltage of the DC-DC converter 100, It is possible to output an electric signal. In addition, the controller 160 may calculate the value of the second voltage V2 from the output signal of the output voltage sensor 150. [

The DC / DC converter 100 determines whether the second voltage V2 of the second battery B1 is lower than the reference voltage (Step 1020).

The controller 160 of the DC-DC converter 100 compares the output voltage, that is, the second voltage V2 with a predetermined reference voltage, and determines whether the second voltage V2 is smaller than the reference voltage. The reference voltage may indicate a voltage at which the electrical components 30 supplied with electrical energy from the second battery B2 can operate normally.

If the second voltage V2 of the second battery B2 is not less than the reference voltage (NO in 1020), the DC-DC converter 100 may repeat the output voltage sensing.

If the second voltage V2 of the second battery B2 is lower than the reference voltage (YES in step 1020), the DC-DC converter 100 senses the first voltage V1 of the first battery B1 1030).

The input voltage sensor 140 of the DC-DC converter 100 measures the value of the first voltage V1, that is, the input voltage of the DC-DC converter 100, and outputs a voltage corresponding to the value of the first voltage V1 It is possible to output an electric signal. In addition, the controller 160 may calculate the value of the first voltage V1 from the output signal of the input voltage sensor 140. [

DC-DC converter 100 determines a first duty ratio Duty1 of the first drive switch Q1 (1040).

The controller 160 of the DC-DC converter 100 may determine the first duty ratio Duty1 of the first drive switch Q1 from the first voltage V1 and the second voltage V2.

The controller 160 uses the first voltage V1, the second voltage V2, the number of turns N1 of the primary coil L1, the number of turns of the secondary coil L2, The first duty ratio Duty1 of the first drive switch Q1 can be calculated from the second duty ratio D2 of the first drive switch N2 and the predetermined second drive switch Q2.

The controller 160 not only can directly calculate the first duty ratio Duty1 of the first drive switch Q1 using Equation 4 but also refers to the first drive switch Q1 (Duty 1) of the first duty ratio (Duty 1). For example, the memory 161 includes a first duty ratio Duty1 of the first drive switch Q1 corresponding to the first voltage V1, the second voltage V2, and the voltages V1 and V2 thereof A controller 160 may store a lookup table and may refer to a lookup table stored in the memory 161 to determine a first drive switch Q1 corresponding to the first voltage V1 and the second voltage V2, The first duty ratio (Duty 1)

The DC-DC converter 100 turns on / off the first drive switch Q1 (1050).

The controller 160 of the DC-DC converter 100 can determine the on / off time of the first drive switch Q1 from the first duty ratio Duty1 and the cycle of switching the first drive switch Q1 have.

The controller 160 may output a first switching signal to turn on / off the first drive switch Q1 according to the on / off time of the first drive switch Q1. The first conversion circuit 110 can convert the first voltage V1 to the third voltage V3 by turning on / off the first drive switch Q1.

The controller 160 may operate the pulse generating circuit 130. The pulse generating circuit 130 may include a second switching signal for turning on and off the second driving switch Q2 and a second switching signal for turning on / Off / turn-on of the reset signal. The second conversion circuit 120 can convert the third voltage V1 to the second voltage V3 by turning on / off the second drive switch Q2 and turning off / on the reset switch Q3 have.

Thus, the DC-DC converter 100 can convert the first voltage V1 to the second voltage V2.

FIG. 7 shows a configuration of a DC-DC converter according to another embodiment.

7, the DC-DC converter 100a includes a first conversion circuit 110, a second conversion circuit 120a, a pulse generation circuit 130, an input voltage sensor 140, An output voltage sensor 150, and a controller 160a.

The configuration and operation of the first conversion circuit 110, the pulse generation circuit 130, the input voltage sensor 140, the output voltage sensor 150 and the controller 160a are the same as those of the first conversion Circuit 110, pulse generation circuit 130, input voltage sensor 140, output voltage sensor 150 and controller 160 may be the same.

The second conversion circuit 120 includes a transformer 121, a second drive switch Q2, a reset capacitor Cr, a reset switch Q3, first and second diodes D1 and D2, A second output inductor Lo2, and a second output capacitor Co2.

The second drive switch Q2, the reset capacitor Cr, the reset switch Q3, the second output inductor Lo2 and the second output capacitor Co2 are connected to the second drive switch Q2, the reset capacitor Cr, the reset switch Q3, the second output inductor Lo2, and the second output capacitor Co2.

The transformer 121 includes a primary coil L1 on the input side, a secondary coil L2 on the output side, a center-tap CT provided in the center of the secondary coil L2, And an iron core for transmitting a magnetic field from the secondary coil L1 to the secondary coil L2.

The secondary coil L2 may be divided into a first coil L2-1 and a second coil L2-2 by an intermediate tap CT. The middle tap CT may be located at the center of the secondary coil L2 and the number of turns of the first coil L2-1 and the number of turns of the second coil L2-2 may be the same. This type of transformer is called a center-tap transformer.

As described above, the transformer 121 including the intermediate tap CT performs the full-wave rectification of the AC voltage and the AC current output from the secondary coil L2 together with the second / third diodes D2 and D3 .

The intermediate tap CT may be connected to the cathode of the second battery B2 via the second output inductor Lo2 and the second diode D2 and the third diode D3 may be connected to the secondary coil of the transformer 121, (L2), respectively. In particular, the anode of the second diode D2 may be connected to one end of the secondary coil L2, and the anode of the third diode D3 may be connected to the other end of the secondary coil L2. The cathode of the second diode D2 and the cathode of the third diode D3 may be connected to the second output capacitor Co2.

The second diode D2 can supply a positive voltage and a positive current output from the secondary coil L2 to the second output inductor Lo2 and the second output capacitor Co2 and the third diode D3, Can rectify the negative voltage and negative current output from the secondary coil L2 and supply it to the second output inductor Lo2 and the second output capacitor Co2.

Therefore, the transformer 121 including the intermediate tap CT and the second / third diodes D2 and D3 rectify both the positive current and the negative current output from the transformer 121 to generate the second output inductor Lo2 and the second output capacitor Co2.

As described above, the DC-DC converter 100a includes the first conversion circuit 110 and the second conversion circuit 120a by sequentially connecting the first conversion circuit 110 and the second conversion circuit 120a, A further improved voltage drop effect can be obtained.

In addition, by sequentially connecting the first conversion circuit 110 and the second conversion circuit 120a, the internal pressure of the switches Q1, Q2, and Q3 can be lowered.

The operation of the DC-DC converter 100a may be the same as the voltage drop operation 1000 shown in FIG.

FIG. 8 shows the configuration of a DC-DC converter according to another embodiment.

8, the DC-DC converter 100b includes a first conversion circuit 110, a second conversion circuit 120, an input voltage sensor 140, an output voltage sensor 150, Controller 160a.

The configuration and operation of the first conversion circuit 110, the second conversion circuit 120, the input voltage sensor 140 and the output voltage sensor 150 are the same as those of the first conversion circuit 110 shown in FIG. 5 The first conversion circuit 110, the second conversion circuit 120, the input voltage sensor 140, and the output voltage sensor 150, as shown in FIG.

The controller 160b may control the operation of the DC-DC converter 100b and may include a memory 161 and a processor 162 for controlling the DC-DC converter 100. [ The memory 161 and the processor 162 may be implemented as separate integrated circuits (ICs), or the memory 161 and the processor 162 may be integrated into one integrated circuit.

The controller 160b controls the opening and closing operations of the first drive switch Q1, the second drive switch Q2 and the reset switch Q3 based on the value of the first voltage V1 and the value of the second voltage V2 Can be controlled.

Specifically, the controller 160b may set the value of the third voltage V3 based on the value of the first voltage V1 and the value of the second voltage V2. The third voltage V3 is a voltage output from the first conversion circuit 110 and input to the second conversion circuit 120. [

The controller 160b may determine the value of the third voltage V3 in a variety of ways.

For example, the controller 160b may set the third voltage V3 to a value of half of the first voltage V1. A voltage equal to the difference between the first voltage V1 and the third voltage V3 may be applied to the first drive switch Q1 when the first drive switch Q1 of the first conversion circuit 110 is switched . Also, a third voltage V3 may be applied to the second drive switch Q2 when the second drive switch Q2 of the second conversion circuit 120 is switched. Accordingly, in order to minimize the switching loss of the first and second driving switches Q1 and Q2, the controller 160b may set the third voltage V3 to a value of half of the first voltage V1.

As another example, the controller 160b may set the third voltage V3 to a value of 1/3 of the first voltage V1. A voltage equal to the difference between the maximum first voltage V1 and the third voltage V3 may be applied to the first drive switch Q1 of the first conversion circuit 110 and the second drive switch Q2 may be supplied with the maximum A voltage twice that of the third voltage V3 can be applied. Therefore, the controller 160b controls the first and second driving switches Q1 and Q2 so that the maximum voltage that can be applied to the first and second driving switches Q1 and Q2 is reduced and the first and second driving switches Q1 and Q2 are operated stably. The voltage V3 can be set to 1/3 of the first voltage V1.

In addition, the controller 160b may variably determine the value of the third voltage V3.

The controller 160b calculates the first duty ratio Duty1 of the first drive switch Q1 from the value of the first voltage V1 and the value of the third voltage V3 using Equation 1 And the second duty ratio Duty2 of the second drive switch Q2 can be calculated from the value of the third voltage V3 and the value of the second voltage V2 by using Equation 3 .

In addition, the controller 160b may determine the first duty ratio Duty1 and the second duty ratio Duty2. For example, the memory 161 may include a first duty ratio Duty1 and a second duty ratio Duty2 corresponding to the first voltage V1, the second voltage V2 and the voltages V1 and V2 The controller 160a may store a lookup table and store the first duty ratio Duty1 corresponding to the first voltage V1 and the second voltage V2 with reference to the lookup table stored in the memory 161. [ And the second duty ratio (Duty 2) can be determined.

The controller 160b controls the opening and closing of the first driving switch Q1 according to the switching cycle of the first driving switch Q1 and the first duty ratio Duty1, It is possible to control the opening and closing of the second drive switch Q2 and the reset switch Q3 in accordance with the opening and closing (switching) period and the second duty ratio Duty2.

The operation of the DC-DC converter 100b will be described below.

FIG. 9 shows the operation of the DC-DC converter shown in FIG.

9, the voltage drop operation 1100 of the DC-DC converter 100b will be described.

The DC-DC converter 100b may perform the voltage drop operation 1100 at predetermined time intervals. For example, the DC-DC converter 100 can perform the voltage drop operation 1100 every cycle of the first drive switch Q1 and the second drive switch Q2.

The DC-DC converter 100b senses the second voltage V2 of the second battery B1 (1110).

The DC / DC converter 100b determines whether the second voltage V2 of the second battery B1 is less than the reference voltage (1120).

If the second voltage V2 of the second battery B2 is not smaller than the reference voltage (NO at 1020), the DC-DC converter 100b can repeat the output voltage sensing, DC converter 100b senses the first voltage V1 of the first battery B1 (1130) if the second voltage V2 is less than the reference voltage (step 1020).

Operations 1110, 1120, and 1130 may be identical to operations 1010, 1020, and 1030 shown in FIG. 6, respectively.

The DC-DC converter 100b determines a first duty ratio Duty1 of the first drive switch Q1 and a second duty ratio Duty2 of the second drive switch Q2 (1040).

The controller 160b of the DC-DC converter 100b may determine the third voltage V3 from the first voltage V1 and the second voltage V2. The controller 160b may determine one duty ratio Duty1 and the second duty ratio Duty2 from the first voltage V1, the second voltage V2 and the third voltage V3.

The controller 160b directly calculates the first duty ratio Duty1 from the first voltage V1 and the third voltage V3 using Equation 1 and calculates the third duty ratio Duty1 using Equation 3. [ The second duty ratio Duty2 can be directly calculated from the third voltage V3 and the second voltage V2.

Further, the controller 160b can determine the first duty ratio (Duty1) and the second duty ratio (Duty2) by referring to the memory (161).

The DC-DC converter 100b turns on / off the first drive switch Q1 (1150).

The controller 160b of the DC-DC converter 100b can determine the on / off time of the first drive switch Q1 from the first duty ratio Duty1 and the switching cycle of the first drive switch Q1 have.

The controller 160b may output a first switching signal that turns on / off the first drive switch Q1 according to the on / off time of the first drive switch Q1. The first conversion circuit 110 can convert the first voltage V1 to the third voltage V3 by turning on / off the first drive switch Q1.

In addition, the DC-DC converter 100b turns on / off the second drive switch Q2 and the reset switch Q3 (1160).

The controller 160 of the DC-DC converter 100b controls the ON / OFF time of the second drive switch Q2 and the ON / OFF time of the second drive switch Q2 from the first duty ratio Duty2 and the cycle of switching the second drive switch Q2 Off time of the transistor Q3 can be determined.

The controller 160b outputs a second switching signal for turning on / off the second driving switch Q2 according to the on / off time of the second driving switch Q2, and outputs the second switching signal for turning on / off the reset switch Q3 The reset switch Q3 can output a reset signal that turns off / on. The second conversion circuit 120 can convert the third voltage V3 to the second voltage V2 by the turn-on / turn-off of the second drive switch Q2 and the turn-off / turn-on of the reset switch Q3 have.

Thus, the DC-DC converter 100b can convert the first voltage V1 to the second voltage V2.

Meanwhile, the disclosed embodiments may be embodied in the form of a recording medium storing instructions executable by a computer. The instructions may be stored in the form of program code and, when executed by a processor, may generate a program module to perform the operations of the disclosed embodiments. The recording medium may be embodied as a computer-readable recording medium.

The computer-readable recording medium includes all kinds of recording media in which instructions that can be decoded by a computer are stored. For example, it may be a ROM (Read Only Memory), a RAM (Random Access Memory), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device, or the like.

The embodiments disclosed with reference to the accompanying drawings have been described above. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. The disclosed embodiments are illustrative and should not be construed as limiting.

1: vehicle 100: DC-DC converter
110: first conversion circuit 120: second conversion circuit
121: Transformer 130: Pulse Generation Circuit
140: input voltage sensor 150: output voltage sensor
160:

Claims (16)

A first battery for outputting power of a first voltage;
A second battery for outputting a power of a second voltage;
And a DC-DC converter that converts a first voltage of the first battery to the second voltage and supplies the converted second voltage to the second battery,
The DC-DC converter includes:
A first output capacitor for outputting a first voltage, a first output capacitor for outputting a third voltage, a first drive switch for controlling a first current output from the first battery, and a first output inductor for preventing a sudden change in the first current Conversion circuit;
A second output switch for outputting the second voltage; a transformer for converting the third voltage to the second voltage; a second drive switch for controlling a second current input to the transformer; A second conversion circuit including a plurality of diodes rectifying the current and outputting the current to the second output capacitor; And
And a controller for controlling opening and closing of the first drive switch in accordance with the first voltage and the second voltage. The method according to claim 1,
Wherein the DC-DC converter further comprises a pulse generation circuit for opening / closing the second drive switch in accordance with a predetermined reference duty ratio. 3. The method of claim 2,
Wherein the controller calculates the duty ratio of the first drive switch from the first voltage, the second voltage, and the reference duty ratio. The method of claim 3,
Wherein the controller outputs a first switching signal that turns on or off the first drive switch in accordance with a duty ratio of the first drive switch. The method according to claim 1,
And the controller further controls opening and closing of the second drive switch in accordance with the first voltage and the second voltage. 6. The method of claim 5,
And the controller calculates the third voltage from the first voltage and the second voltage. The method according to claim 6,
Wherein the controller calculates a duty ratio of the first drive switch and a duty ratio of the second drive switch from the first voltage, the second voltage, and the third voltage. 8. The method of claim 7,
Wherein the controller outputs a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch and for turning the second driving switch on or off according to a duty ratio of the second driving switch, And outputs a second switching signal to turn off. A direct current-to-direct current converter for a vehicle which converts a first voltage outputted from a first battery to a second voltage outputted from a second battery,
A first output capacitor connected between the first output capacitor and the anode of the first battery, a first output capacitor connected to the first output capacitor and connected to the first output capacitor, and a second output capacitor connected between the anode of the first battery and the first output capacitor, A first conversion circuit including a first drive switch for controlling a current;
A second output capacitor connected to the first conversion circuit to receive the third voltage and a secondary coil connected to the second battery to output the second voltage; A second drive switch connected in series with the transformer to control a second current input to the transformer and a plurality of diodes rectifying the current output from the transformer and outputting the rectified current to the second output capacitor, A second conversion circuit comprising; And
And a controller for controlling the opening and closing of the first drive switch in accordance with the first voltage and the second voltage. 10. The method of claim 9,
Further comprising a pulse generation circuit for opening / closing the second drive switch in accordance with a predetermined reference duty ratio. 11. The method of claim 10,
Wherein the controller calculates the duty ratio of the first drive switch from the first voltage, the second voltage, and the reference duty ratio. 12. The method of claim 11,
Wherein the controller outputs a first switching signal for turning on or off the first drive switch according to a duty ratio of the first drive switch. 10. The method of claim 9,
And the controller further controls opening and closing of the second drive switch in accordance with the first voltage and the second voltage. 14. The method of claim 13,
Wherein the controller calculates the third voltage from the first voltage and the second voltage. 15. The method of claim 14,
Wherein the controller calculates a duty ratio of the first drive switch and a duty ratio of the second drive switch from the first voltage, the second voltage, and the third voltage. 16. The method of claim 15,
Wherein the controller outputs a first switching signal for turning on or off the first driving switch according to a duty ratio of the first driving switch and for turning the second driving switch on or off according to a duty ratio of the second driving switch, And outputs a second switching signal to turn off the DC-DC converter.

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