JP2014241707A - Power supply and control method therefor - Google Patents

Abstract

To provide a power supply device capable of easily downsizing a capacitor provided in a port. A primary side circuit, a secondary side circuit magnetically coupled to the primary side circuit by a transformer, and first and second ports of the primary side circuit and the secondary side circuit are provided. Of the four ports including the third and fourth ports, power is switched between two arbitrary ports by switching in the power conversion unit configured in each of the primary side circuit and the secondary side circuit. A power supply device including a power supply circuit in parallel and a capacitor provided in the four ports, wherein a phase of a switching waveform in the power conversion unit is between the power supply circuits. A power supply device characterized by being different. [Selection] Figure 1

Description

  The present invention relates to a power supply apparatus capable of converting power between any two of four ports and a control method thereof.

  Conventionally, a power supply device capable of converting power between any two of the four ports is known (see, for example, Patent Document 1).

JP 2011-193713 A

  However, with the technique of Patent Document 1 alone, the ripple current of the capacitors provided at each of the four ports tends to be large, and it has been difficult to downsize these capacitors. It is an object of the present invention to provide a power supply device and a control method therefor that can easily reduce the size of a capacitor provided in a port.

In order to achieve the above object, the present invention provides:
A primary side circuit; a secondary side circuit magnetically coupled to the primary side circuit by a transformer; and first and second ports of the primary side circuit and third and second sides of the secondary side circuit. Of the four ports including the fourth port, power is converted between any two ports by switching in a power conversion unit configured in each of the primary circuit and the secondary circuit. A power supply device including a power supply circuit in parallel and a capacitor provided in the four ports,
The power supply device is characterized in that the phase of the switching waveform in the power conversion unit is different between the power supply circuits.

In order to achieve the above object, the present invention provides:
A primary side circuit; a secondary side circuit magnetically coupled to the primary side circuit by a transformer; and first and second ports of the primary side circuit and third and second sides of the secondary side circuit. Of the four ports including the fourth port, power is converted between any two ports by switching in a power conversion unit configured in each of the primary circuit and the secondary circuit. A power supply device control method comprising a power supply circuit in parallel and a capacitor provided in the four ports,
The present invention provides a method for controlling a power supply device, wherein the phase of a switching waveform in the power converter is made different between the power supply circuits.

  According to the present invention, the capacitor provided in the port can be easily downsized.

The block diagram which showed the structural example of the power converter circuit which is one Embodiment of a power supply device Circuit configuration diagram showing an example of a power supply circuit configured in a power conversion circuit Block diagram showing configuration example of control circuit Timing chart showing an example of operation of the power conversion circuit Current waveform on simulation when power supply circuit is operated with only one system The figure which showed the energization path | route of each current which flows into a power supply circuit in period T1 of FIG. The figure which showed the energization path | route of each current which flows into a power supply circuit in period T2 of FIG. The figure which showed the energization path | route of each electric current which flows into a power supply circuit in period T3 of FIG. The figure which showed the energization path | route of each electric current which flows into a power supply circuit in period T4 of FIG. Timing chart showing an example of the state in which the phase of the switching waveform in the power converter differs between power supply circuits Simulation waveform of ripple current flowing in capacitor when there is no phase difference between power supply circuits Simulation waveform of ripple current flowing in capacitor when phase difference between power supply circuits is 90 °

<Configuration of power conversion circuit system 101>
FIG. 1 is a diagram showing a power conversion circuit system 101 including a power conversion circuit 10 which is an embodiment of a power supply device according to the present invention. The power conversion circuit system 101 is a power conversion device configured to include a power conversion circuit 10, a control circuit 50, and a sensor circuit 70, for example.

  The power conversion circuit system 101 includes, for example, a primary high-voltage load LA connected to the first input / output port PA, a primary low-voltage load LC connected to the second input / output port PC, and a primary Side low voltage system power supply PSC. The primary side low voltage system power supply PSC supplies power to the primary side low voltage system load LC that operates in the same voltage system (for example, 12 V system) as the primary side low voltage system power supply PSC. Further, the primary side low voltage power source PSC is connected to the primary side high voltage system load LA operating in a voltage system different from the primary side low voltage system power source PSC (for example, 48V system higher than 12V system). , 12 is supplied with the boosted power by the primary side full bridge circuit 200 (described later in FIG. 2). A specific example of the primary side low-voltage power supply PSC is a secondary battery such as a lead battery.

  For example, the power conversion circuit system 101 includes a secondary side high voltage system load LB and a secondary side high voltage system power source PSB connected to the third input / output port PB, and a secondary side connected to the fourth input / output port PD. Side low voltage system load LD. The secondary side high voltage system power supply PSB supplies power to the secondary side high voltage system load LB that operates in the same voltage system as the secondary side high voltage system power supply PSB (for example, 288V system higher than 12V system and 48V system). Supply. The secondary side high voltage system power supply PSB is connected to the secondary side low voltage system load LD that operates in a voltage system different from the secondary side high voltage system power supply PSB (for example, 72V system lower than the 288V system). , 12 of the secondary side full bridge circuit 300 (which will be described later with reference to FIG. 2). A specific example of the secondary side high voltage power supply PSB is a secondary battery such as a lithium ion battery.

  The power conversion circuit 10 has the four input / output ports described above, selects any two input / output ports from the four input / output ports, and a power supply circuit 11 between the two input / output ports. , 12 has a function of performing power conversion. The first input / output port PA is an input / output node common to the power supply circuits 11 and 12 connected in parallel to the first input / output port PA, and can be used for both input and output. The same applies to the other three input / output ports described above.

  The power conversion circuit 10 includes two power supply circuits 11 and 12 connected in parallel between the first and second input / output ports PA and PC and the third and fourth input / output ports PB and PD. It is a DC-DC converter. By providing a plurality of power supply circuits redundantly in this way, the output power that can be supplied to each load LA, LB, LC, LD is increased, or some of the power supply circuits are out of order. The fail-safe performance can be improved.

  The powers Wa, Wc, Wb, and Wd are input power or output power at the first input / output port PA, the second input / output port PC, the third input / output port PB, and the fourth input / output port PD, respectively. The powers Wa1, Wc1, Wb1, Wd1 input or output in the power supply circuit 11 are respectively connected to the first input / output port PA1 connected to the first input / output port PA1, and to the second input / output port PC. The power in the fourth input / output port PD1 connected to the input / output port PC1, the third input / output port PB1 connected to the third input / output port PB1, and the fourth input / output port PD. The same applies to the powers Wa2, Wc2, Wb2, and Wd2 that are input or output in the power supply circuit 12.

  The power conversion circuit 10 includes a capacitor C1 provided in the first input / output port PA, a capacitor C3 provided in the second input / output port PC, a capacitor C2 provided in the third input / output port PB, and a fourth input / output port. And a capacitor C4 provided in the PD. Specific examples of the capacitors C1, C2, C3, and C4 include film capacitors (film capacitors).

  The capacitor C1 is inserted between the high potential side terminal 602 of the first input / output port PA and the low potential side terminal 604 of the first input / output port PA and the second input / output port PC. The capacitor C3 is inserted between the high potential side terminal 606 of the second input / output port PC and the low potential side terminal 604 of the first input / output port PA and the second input / output port PC. The capacitor C2 is inserted between the high potential side terminal 608 of the third input / output port PB and the low potential side terminal 610 of the third input / output port PB and the fourth input / output port PD. The capacitor C4 is inserted between the terminal 612 on the high potential side of the fourth input / output port PD and the terminal 610 on the low potential side of the third input / output port PB and the fourth input / output port PD.

  The capacitor C1 may be provided in the internal circuit on the power supply circuits 11 and 12 side with respect to the first input / output port PA, or the primary side high voltage system provided on the opposite side to the power supply circuits 11 and 12. It may be provided in an external circuit on the load LA side. The same applies to the capacitors C2, C3, and C4 in that they may be provided inside or outside the power conversion circuit 10.

  FIG. 2 is a circuit configuration diagram of the power supply circuit 11. Next, the configuration of the power supply circuit 11 will be described with reference to FIG. Since the circuit configuration of the power supply circuit 12 may be the same as that of the power supply circuit 11, the description thereof is omitted.

  The power supply circuit 11 includes a primary side conversion circuit 20 and a secondary side conversion circuit 30. The primary side conversion circuit 20 and the secondary side conversion circuit 30 are magnetically coupled by a transformer 400 (center tap transformer).

  The primary side conversion circuit 20 is a primary side circuit configured to include a primary full bridge circuit 200, a first input / output port PA1, and a second input / output port PC1. The primary side full bridge circuit 200 includes a primary side coil 202 of the transformer 400, a primary side magnetic coupling reactor 204, a primary side first upper arm U1, and a primary side first lower arm / U1, This is a primary power conversion unit configured to include a primary second upper arm V1 and a primary second lower arm / V1. Here, the primary side first upper arm U1, the primary side first lower arm / U1, the primary side second upper arm V1, and the primary side second lower arm / V1 are, for example, N The switching element includes a channel-type MOSFET and a body diode that is a parasitic element of the MOSFET. A diode may be additionally connected in parallel with the MOSFET.

  The primary-side full bridge circuit 200 includes a primary-side positive bus 298 connected to high-potential-side terminals 602 and 613 of the first input / output ports PA and PA1, the first input / output ports PA and PA1, and the second input. The output ports PC and PC1 have primary-side negative electrode buses 299 connected to terminals 604 and 614 on the low potential side.

  A primary side first arm circuit in which a primary side first upper arm U1 and a primary side first lower arm / U1 are connected in series between a primary side positive electrode bus 298 and a primary side negative electrode bus 299. 207 is attached. The primary side first arm circuit 207 is a primary side first power conversion circuit unit capable of performing a power conversion operation by an on / off switching operation of the primary side first upper arm U1 and the primary side first lower arm / U1 ( Primary side U-phase power conversion circuit unit). Further, between the primary side positive electrode bus 298 and the primary side negative electrode bus 299, a primary side second upper arm V1 and a primary side second lower arm / V1 connected in series are connected. An arm circuit 211 is attached in parallel with the primary side first arm circuit 207. The primary side second arm circuit 211 is a primary side second power conversion circuit unit capable of performing a power conversion operation by ON / OFF switching operation of the primary side second upper arm V1 and the primary side second lower arm / V1 ( Primary side V-phase power conversion circuit unit).

  A primary side coil 202 and a primary side magnetic coupling reactor 204 are provided at a bridge portion connecting the middle point 207m of the primary side first arm circuit 207 and the middle point 211m of the primary side second arm circuit 211. ing. The connection relationship will be described in more detail with respect to the bridge portion. One end of the primary side first reactor 204a of the primary side magnetic coupling reactor 204 is connected to the midpoint 207m of the primary side first arm circuit 207. And one end of the primary side coil 202 is connected to the other end of the primary side 1st reactor 204a. Further, one end of the primary second reactor 204 b of the primary magnetic coupling reactor 204 is connected to the other end of the primary coil 202. Then, the other end of the primary side second reactor 204 b is connected to the midpoint 211 m of the primary side second arm circuit 211. The primary-side magnetic coupling reactor 204 includes a primary-side first reactor 204a and a primary-side second reactor 204b that is magnetically coupled to the primary-side first reactor 204a.

  A midpoint 207m is a primary first intermediate node between the primary first upper arm U1 and the primary first lower arm / U1, and a midpoint 211m is the primary second upper arm V1. And a primary side second lower arm / V1.

  The first input / output ports PA and PA1 are ports provided between the primary positive electrode bus 298 and the primary negative electrode bus 299. The first input / output port PA (PA1) includes a terminal 602 and a terminal 604 (terminal 613 and terminal 614). The second input / output port PC (PC1) is a port provided between the primary negative electrode bus 299 and the center tap 202m of the primary coil 202. The second input / output port PC (PC1) includes a terminal 604 and a terminal 606 (terminal 614 and terminal 616).

  The center tap 202m is connected to terminals 606 and 616 on the high potential side of the second input / output ports PC and PC1. The center tap 202m is an intermediate connection point between the primary first winding 202a and the primary second winding 202b configured in the primary coil 202.

  The secondary side conversion circuit 30 is a secondary side circuit configured to include a secondary side full bridge circuit 300, a third input / output port PB1, and a fourth input / output port PD1. The secondary side full bridge circuit 300 includes a secondary side coil 302 of the transformer 400, a secondary side magnetic coupling reactor 304, a secondary side first upper arm U2, and a secondary side first lower arm / U2. This is a secondary side power converter configured to include the secondary side second upper arm V2 and the secondary side second lower arm / V2. Here, each of the secondary side first upper arm U2, the secondary side first lower arm / U2, the secondary side second upper arm V2, and the secondary side second lower arm / V2 is, for example, N The switching element includes a channel-type MOSFET and a body diode that is a parasitic element of the MOSFET. A diode may be additionally connected in parallel with the MOSFET.

  The secondary side full bridge circuit 300 includes a secondary side positive bus 398 connected to the high potential side terminals 608 and 618 of the third input / output ports PB and PB1, a third input / output port PB and PB1, and a fourth input. It has a secondary negative electrode bus 399 connected to the low potential side terminals 610, 620 of the output ports PD, PD1.

  A secondary side first arm circuit in which a secondary side first upper arm U2 and a secondary side first lower arm / U2 are connected in series between a secondary side positive electrode bus 398 and a secondary side negative electrode bus 399. 307 is attached. The secondary side first arm circuit 307 is a secondary side first power conversion circuit unit capable of performing a power conversion operation by on / off switching operation of the secondary side first upper arm U2 and the secondary side first lower arm / U2. Secondary side U-phase power conversion circuit unit). Furthermore, a secondary side second upper arm V2 and a secondary side second lower arm / V2 are connected in series between the secondary side positive electrode bus 398 and the secondary side negative electrode bus 399. An arm circuit 311 is attached in parallel with the secondary side first arm circuit 307. The secondary side second arm circuit 311 is a secondary side second power conversion circuit unit capable of performing a power conversion operation by an on / off switching operation of the secondary side second upper arm V2 and the secondary side second lower arm / V2. Secondary side V-phase power conversion circuit unit).

  A secondary coil 302 and a secondary magnetic coupling reactor 304 are provided at a bridge portion connecting the midpoint 307m of the secondary side first arm circuit 307 and the midpoint 311m of the secondary side second arm circuit 311. ing. The connection relationship will be described in more detail with respect to the bridge portion. One end of the secondary side first reactor 304a of the secondary side magnetic coupling reactor 304 is connected to the midpoint 311m of the secondary side second arm circuit 311. Then, one end of the secondary coil 302 is connected to the other end of the secondary first reactor 304a. Furthermore, one end of the secondary second reactor 304 b of the secondary magnetic coupling reactor 304 is connected to the other end of the secondary coil 302. Then, the other end of the secondary second reactor 304b is connected to the midpoint 307m of the secondary first arm circuit 307. The secondary-side magnetic coupling reactor 304 includes a secondary-side first reactor 304a and a secondary-side second reactor 304b that is magnetically coupled to the secondary-side first reactor 304a.

  The middle point 307m is a secondary side first intermediate node between the secondary side first upper arm U2 and the secondary side first lower arm / U2, and the middle point 311m is the secondary side second upper arm V2. And a secondary side second intermediate node between the secondary side second lower arm / V2.

  The third input / output ports PB and PB1 are ports provided between the secondary positive electrode bus 398 and the secondary negative electrode bus 399. The third input / output port PB (PB1) includes a terminal 608 and a terminal 610 (terminal 618 and terminal 620). The fourth input / output port PD (PD1) is a port provided between the secondary negative electrode bus 399 and the center tap 302m of the secondary coil 302. The fourth input / output port PD (PD1) includes a terminal 610 and a terminal 612 (terminal 620 and terminal 622).

  The center tap 302m is connected to terminals 612 and 622 on the high potential side of the fourth input / output ports PD and PD1. The center tap 302m is an intermediate connection point between the secondary side first winding 302a and the secondary side second winding 302b configured in the secondary side coil 302.

  In FIG. 1, the power conversion circuit 10 of the power conversion circuit system 101 includes a sensor circuit 70. The sensor circuit 70 detects the output value Do at the first to fourth input / output ports PA, PC, PB, PD at a predetermined detection cycle, and outputs a detection signal corresponding to the output value Do to the control circuit 50. It is a sensor part. Examples of the output value Do include power values of power Wa, Wc, Wb, and Wd, output voltage values, and output current values in the first to fourth input / output ports PA, PC, PB, and PD. The sensor circuit 70 may be a monitor unit that monitors the voltages at the midpoints 207m, 211m, 307m, and 311m. The sensor circuit 70 may be provided inside or outside the power conversion circuit 10.

  The power conversion circuit 10 includes a control circuit 50. The control circuit 50 makes the output value Do of the first to fourth input / output ports PA, PC, PB, PD follow the output target value Dot of the first to fourth input / output ports PA, PC, PB, PD. It is a control unit that controls the outputs of the power supply circuits 11 and 12. The control circuit 50 is an electronic circuit provided with a microcomputer incorporating a CPU, for example. The output target value Dot is a value commanded from a predetermined device, and may be the output target voltage value Vot, the output target current value Iot, or the output target power value Wot. The control circuit 50 may be provided inside or outside the power conversion circuit 10.

  The control circuit 50 feeds back the output value Do detected by the sensor circuit 70, for example, and the power supply circuits 11, 12 so that the deviation between the output target value Dot and the detected value of the output value Do fed back becomes zero. Control each output power. The control circuit 50 may be a circuit that controls the output voltage of each of the power supply circuits 11 and 12 or may be a circuit that controls the output current of each of the power supply circuits 11 and 12.

  For example, the control circuit 50 changes the value of the control parameter P that can control the output power of each of the power supply circuits 11 and 12 by power conversion. In this case, there are two types of control parameters P, which are the phase difference φ and the duty ratio (ON time δ).

  The phase difference φ is a switching timing shift (time lag) between the power conversion circuit units of the same phase between the primary side full bridge circuit 200 and the secondary side full bridge circuit 300. The duty ratio (ON time δ) is a duty ratio (ON time) of a switching waveform in each power conversion circuit unit configured in the primary side full bridge circuit 200 and the secondary side full bridge circuit 300.

  These two control parameters P can be controlled independently of each other. The control circuit 50 controls the power supply circuits 11 and 12 by duty ratio control and / or phase control of the primary side full bridge circuit 200 and the secondary side full bridge circuit 300 using the phase difference φ and the duty ratio (ON time δ). Change each output of.

  FIG. 3 is a block diagram of the control circuit 50. The control circuit 50 performs switching control of each switching element such as the primary first upper arm U1 of the primary conversion circuit 20 and each switching element such as the secondary first upper arm U2 of the secondary conversion circuit 30. It is a control part which has a function to perform. The control circuit 50 includes a power conversion mode determination processing unit 502, a phase difference φ determination processing unit 504, an on-time δ determination processing unit 506, a primary side switching processing unit 508, and a secondary side switching processing unit 510. Consists of including. The control circuit 50 is an electronic circuit provided with a microcomputer incorporating a CPU, for example.

  The power conversion mode determination processing unit 502 selects and determines an operation mode from power conversion modes A to L of the power conversion circuit 10 described below based on an external signal (not shown). The power conversion mode is a mode A in which the power input from the first input / output port PA is converted and output to the second input / output port PC, and the power input from the first input / output port PA is converted to a third mode. There is a mode B for outputting to the input / output port PB and a mode C for converting the power input from the first input / output port PA and outputting it to the fourth input / output port PD.

  A mode D for converting the power input from the second input / output port PC and outputting it to the first input / output port PA, and a third input / output port for converting the power input from the second input / output port PC There is a mode E that outputs to the PB and a mode F that converts the power input from the second input / output port PC and outputs it to the fourth input / output port PD.

  Furthermore, the mode G that converts the power input from the third input / output port PB and outputs it to the first input / output port PA, and the second input / output port that converts the power input from the third input / output port PB. There is a mode H for outputting to the PC and a mode I for converting the power input from the third input / output port PB and outputting it to the fourth input / output port PD.

  Then, the mode J for converting the power input from the fourth input / output port PD and outputting it to the first input / output port PA, and the second input / output port for converting the power input from the fourth input / output port PD There is a mode K for outputting to the PC and a mode L for converting the power input from the fourth input / output port PD and outputting it to the third input / output port PB.

  The phase difference φ determination processing unit 504 is configured to cause the power conversion circuit 10 to function as a DC-DC converter circuit, so that the phase difference between the switching periods of the switching elements between the primary side conversion circuit 20 and the secondary side conversion circuit 30. Has a function to set φ.

  The on-time δ determination processing unit 506 operates switching elements of the primary side conversion circuit 20 and the secondary side conversion circuit 30 in order to cause the primary side conversion circuit 20 and the secondary side conversion circuit 30 to function as step-up / down circuits, respectively. It has a function of setting the on time δ.

  The primary side switching processing unit 508 includes the primary side first upper arm U1 and the primary side based on the outputs of the power conversion mode determination processing unit 502, the phase difference φ determination processing unit 504, and the on-time δ determination processing unit 506. The switching function of each switching element of the side first lower arm / U1, the primary second upper arm V1, and the primary second lower arm / V1 is provided.

  The secondary side switching processing unit 510 includes a secondary side first upper arm U2 and a secondary side based on outputs of the power conversion mode determination processing unit 502, the phase difference φ determination processing unit 504, and the on-time δ determination processing unit 506. The switching function of each switching element of the side first lower arm / U2, the secondary side second upper arm V2, and the secondary side second lower arm / V2 is provided.

<Operation of Power Conversion Circuit System 101>
The operation of the power conversion circuit system 101 will be described with reference to FIGS. For example, when an external signal requesting to operate the power conversion mode of the power conversion circuit 10 as mode F is input, the power conversion mode determination processing unit 502 of the control circuit 50 The conversion mode is determined as mode F. At this time, the voltage input to the second input / output port PC1 is boosted by the boosting function of the primary side conversion circuit 20, and the boosted voltage is increased by the function of the power conversion circuit 10 as the DC-DC converter circuit. The signal is transmitted to the input / output port PB1 side, further stepped down by the step-down function of the secondary side conversion circuit 30, and output from the fourth input / output port PD1.

  Here, the step-up / step-down function of the primary side conversion circuit 20 will be described in detail. Focusing on the second input / output port PC1 and the first input / output port PA1, the terminal 616 of the second input / output port PC1 is connected in series to the primary side first winding 202a and the primary side first winding 202a. The primary side first arm circuit 207 is connected to the midpoint 207m through the primary side first reactor 204a. Since both ends of the primary side first arm circuit 207 are connected to the first input / output port PA1, there is a step-up / step-down voltage between the terminal 616 of the second input / output port PC1 and the first input / output port PA1. A circuit is attached.

  Further, the terminal 616 of the second input / output port PC1 is connected to the primary side via the primary side second winding 202b and the primary side second reactor 204b connected in series to the primary side second winding 202b. The second arm circuit 211 is connected to the midpoint 211m. Since both ends of the primary side second arm circuit 211 are connected to the first input / output port PA1, there is no up / down between the terminal 616 of the second input / output port PC1 and the first input / output port PA1. The pressure circuit is attached in parallel. Since the secondary side conversion circuit 30 is a circuit having substantially the same configuration as the primary side conversion circuit 20, between the terminal 622 of the fourth input / output port PD1 and the third input / output port PB1, Two step-up / step-down circuits are connected in parallel. Therefore, the secondary side conversion circuit 30 has a step-up / step-down function like the primary side conversion circuit 20.

  Next, the function of the power supply circuit 11 as a DC-DC converter circuit will be described in detail. Focusing on the first input / output port PA1 and the third input / output port PB1, the first input / output port PA1 is connected to the primary side full bridge circuit 200, and the third input / output port PB1 is connected to the secondary side full bridge. A circuit 300 is connected. Then, the primary side coil 202 provided in the bridge portion of the primary side full bridge circuit 200 and the secondary side coil 302 provided in the bridge portion of the secondary side full bridge circuit 300 are magnetically coupled, so that the transformer It functions as 400 (center tap type transformer having a winding number of 1: N). Therefore, by adjusting the phase difference between the switching periods of the switching elements of the primary-side full-bridge circuit 200 and the secondary-side full-bridge circuit 300, the power input to the first input / output port PA1 is converted and the third input The power can be transmitted to the output port PB1, or the power input to the third input / output port PB1 can be converted and transmitted to the first input / output port PA1.

  FIG. 4 is a timing chart of ON / OFF switching waveforms of each arm configured in the power conversion circuit 10 under the control of the control circuit 50. In FIG. 4, U1 is an ON / OFF waveform of the primary first upper arm U1, V1 is an ON / OFF waveform of the primary second upper arm V1, and U2 is the secondary first upper arm U2. It is an on / off waveform, and V2 is an on / off waveform of the secondary second upper arm V2. The primary-side first lower arm / U1, the primary-side second lower arm / V1, the secondary-side first lower arm / U2, and the secondary-side second lower arm / V2 have ON / OFF waveforms respectively. This is a waveform obtained by inverting the on / off waveform of the first upper arm U1, the primary second upper arm V1, the secondary first upper arm U2, and the secondary second upper arm V2 (not shown). Note that a dead time is preferably provided between the on-off waveforms of the upper and lower arms so that no through current flows when both the upper and lower arms are turned on. In FIG. 4, the high level represents the on state and the low level represents the off state.

  Here, the step-up / step-down ratio of the primary side conversion circuit 20 and the secondary side conversion circuit 30 can be changed by changing the ON times δ of U1, V1, U2, and V2. For example, by making the ON times δ of U1, V1, U2, and V2 equal to each other, the step-up / step-down ratio of the primary side conversion circuit 20 and the step-up / step-down ratio of the secondary side conversion circuit 30 can be made equal.

  The ON time δ determination processing unit 506 makes the ON times δ of U1, V1, U2, and V2 equal to each other so that the step-up / step-down ratios of the primary side conversion circuit 20 and the secondary side conversion circuit 30 are equal to each other (each ON time δ = primary side ON time δ1 = secondary side ON time δ2 = time value α).

  The step-up / step-down ratio of the primary side conversion circuit 20 is determined by the duty ratio that is the ratio of the on-time δ to the switching cycle T of the switching elements (arms) configured in the primary side full bridge circuit 200. Similarly, the step-up / step-down ratio of the secondary side conversion circuit 30 is determined by the duty ratio that is the ratio of the ON time δ to the switching period T of the switching elements (arms) configured in the secondary side full bridge circuit 300. The step-up / step-down ratio of the primary side conversion circuit 20 is a transformation ratio between the first input / output port PA1 and the second input / output port PC1, and the step-up / step-down ratio of the secondary side conversion circuit 30 is the third input / output port PB1. And the fourth input / output port PD1.

So, for example,
The step-up / down ratio of the primary side conversion circuit 20 = the voltage of the second input / output port PC1 / the voltage of the first input / output port PA1 = δ1 / T = α / T
The step-up / step-down ratio of the secondary conversion circuit 30 = the voltage at the fourth input / output port PD1 / the voltage at the third input / output port PB1 = δ2 / T = α / T
It is expressed. That is, the step-up / step-down ratio of the primary side conversion circuit 20 and the secondary side conversion circuit 30 is the same value (= α / T).

  4 represents the on time δ1 of the primary first upper arm U1 and the primary second upper arm V1, and the secondary first upper arm U2 and the secondary second upper. This represents the on time δ2 of the arm V2. The switching period T of the arm configured in the primary side full bridge circuit 200 and the switching period T of the arm configured in the secondary side full bridge circuit 300 are equal times.

  The phase difference between U1 and V1 is operated at 180 degrees (π), and the phase difference between U2 and V2 is also operated at 180 degrees (π). Furthermore, by changing the phase difference φ between U1 and U2, the amount of power transmitted between the primary side conversion circuit 20 and the secondary side conversion circuit 30 can be adjusted, and if the phase difference φ> 0, Transmission from the primary side conversion circuit 20 to the secondary side conversion circuit 30 can be performed from the secondary side conversion circuit 30 to the primary side conversion circuit 20 if the phase difference φ <0.

  The phase difference φ is a switching timing shift (time lag) between the power conversion circuit units of the same phase between the primary side full bridge circuit 200 and the secondary side full bridge circuit 300. For example, the phase difference φ is a switching timing shift between the primary side first arm circuit 207 and the secondary side first arm circuit 307, and the primary side second arm circuit 211 and the secondary side second arm circuit 307. This is a difference in switching timing with the arm circuit 311. These deviations are controlled to be equal to each other. That is, the phase difference φ between U1 and U2 and the phase difference φ between V1 and V2 are controlled to the same value.

  Therefore, for example, when an external signal requesting to operate the power conversion mode of the power conversion circuit 10 as the mode F is input, the power conversion mode determination processing unit 502 determines to select the mode F. The on-time δ determination processing unit 506 boosts when the primary side conversion circuit 20 functions as a booster circuit that boosts the voltage input to the second input / output port PC1 and outputs the boosted voltage to the first input / output port PA1. An on-time δ that defines the ratio is set. Note that the secondary side conversion circuit 30 steps down the voltage input to the third input / output port PB1 at the step-down ratio defined by the on-time δ set by the on-time δ determination processing unit 506, thereby reducing the fourth input / output. It functions as a step-down circuit that outputs to the port PD1. Further, the phase difference φ determination processing unit 504 sets the phase difference φ for transmitting the power input to the first input / output port PA1 to the third input / output port PB1 with a desired power transmission amount.

  The primary side switching processing unit 508 includes a primary side first upper arm so that the primary side conversion circuit 20 functions as a booster circuit and the primary side conversion circuit 20 functions as a part of the DC-DC converter circuit. The switching control of each switching element of U1, the primary side first lower arm / U1, the primary side second upper arm V1, and the primary side second lower arm / V1 is performed.

  The secondary side switching processing unit 510 has a secondary side first upper arm so that the secondary side conversion circuit 30 functions as a step-down circuit and the secondary side conversion circuit 30 functions as a part of the DC-DC converter circuit. Switching control is performed on the switching elements of U2, the secondary side first lower arm / U2, the secondary side second upper arm V2, and the secondary side second lower arm / V2.

  As described above, the primary side conversion circuit 20 and the secondary side conversion circuit 30 can function as a step-up circuit or a step-down circuit, and the power conversion circuit 10 can also function as a bidirectional DC-DC converter circuit. Can do. Therefore, power conversion can be performed in all the power conversion modes A to L, in other words, power conversion can be performed between two input / output ports selected from among the four input / output ports. .

  Such control is executed for both the power supply circuit 11 and the power supply circuit 12. That is, the control circuit 50 has both the power supply circuits 11 and 12 so that the output value Do of the first to fourth input / output ports PA, PC, PB, and PD detected by the sensor circuit 70 follows the output target value Dot. The duty ratio and the phase difference φ are changed.

  FIG. 5 is a simulation waveform showing the current flow of each part shown in FIG. 2 when only one of the power supply circuit 11 and the power supply circuit 12 is operated.

  The current I1 indicates the current flowing through the secondary coil 302 of the transformer 400, and the current value when the current I1 flows from the secondary second winding 302b side to the secondary first winding 302a side. Positive value. The current I2 indicates the current flowing through the primary side coil 202 of the transformer 400, and the current value when the current I2 flows from the primary side first winding 202b side to the primary side first winding 202a side. Positive value. The current I3 indicates a discharge current flowing from the capacitor C1 to the terminal 613 of the first input / output port PA1, and the current value when the current I3 is flowing in the direction of discharging the capacitor C1 is a positive value. The current I4 indicates a current flowing in the current path between the terminal 616 of the second input / output port PC1 and the center tap 202m, and the current value when the current I4 flows from the terminal 616 side to the center tap 202m side is positive. The value of The current I5 indicates a ripple current flowing through the capacitor C1, and the current value when the current I5 is flowing in the direction of charging the capacitor C1 is a positive value.

  FIG. 5 shows the second input / output port by converting the power of the third input / output port PB1 and outputting the converted power to the first input / output port PA1, and converting the power of the first input / output port PA1. A state is shown in which the control circuit 50 performs switching control of the power supply circuit so as to output the converted power to the PC 1.

  The sum of the periods T1 to T8 shown in FIG. 5 is a switching cycle T (360 °) which is one cycle of the switching waveform shown in FIG. Further, the timings t1 to t9 shown in FIG. 5 correspond to the timings t1 to t9 shown in FIG.

  FIG. 6 is a diagram showing energization paths of currents flowing through the power supply circuit in the period T1 shown in FIG. 5 by arrows. FIG. 7 is a diagram showing energization paths of currents flowing through the power supply circuit in the period T2 shown in FIG. 5 by arrows. FIG. 8 is a diagram showing energization paths of currents flowing through the power supply circuit in the period T3 shown in FIG. 5 by arrows. FIG. 9 is a diagram showing energization paths of currents flowing through the power supply circuit in the period T4 shown in FIG. 5 by arrows. 6 to 9, the arm surrounded by a dotted circle represents that the arm is in the on state, and the other arms represent the arm that is in the off state.

  FIG. 6 shows a state where energy is stored in the equivalent inductance L of the transformer 400 and the primary side magnetic coupling reactor 204 by the current I1 flowing through the secondary side full bridge circuit 300 in the period T1 of FIG. Show.

  In the period T1, as the current I1 increases, the current I2 flowing through the primary side coil 202 and the primary side magnetic coupling reactor 204 of the transformer 400 increases. On the other hand, the current component of the ripple current I5 flowing in the capacitor C1 during the period T1 is a constant discharge current I3 supplied from the capacitor C1 to the load connected to the first input / output port PA1.

  FIG. 7 shows a state in which the energy stored in the equivalent inductance L of the transformer 400 and the primary side magnetic coupling reactor 204 is transmitted to the first input / output port PA1 in the period T2 of FIG. ing.

  The current value of the current I2 flowing in the period T2 is substantially constant. On the other hand, the ripple current I5 flowing in the capacitor C1 during the period T2 is overlapped with three kinds of current components (currents I2, I3, and I4).

  The current I2 flowing in the period T2 is a current component that charges the capacitor C1 with electric power (current) via the equivalent inductance L that combines the transformer 400 and the primary-side magnetic coupling reactor 204. The current I3 flowing in the period T2 is a constant current component that discharges the capacitor C1 in a direction in which charges are discharged from the capacitor C1 to the load connected to the first input / output port PA1. The current I4 flowing in the period T2 is a current component that discharges the capacitor C1 in a direction in which charges are discharged from the capacitor C1 to the load connected to the second input / output port PC1 and the capacitor C3. The voltage of the first input / output port PA1 is stepped down to the voltage of the second input / output port PC1 by the current I4 flowing in the period T2.

  FIG. 8 shows that the energy stored in the equivalent inductance L of the transformer 400 and the primary side magnetic coupling reactor 204 is reset using the voltage of the first input / output port PA1 in the period T3 of FIG. Indicates the state. The period T3 is a preparation period for switching the phase of the power conversion circuit unit energized on the primary side and the secondary side from the U phase to the V phase.

  In the period T3, as the current I1 decreases, the current I2 flowing through the primary side coil 202 and the primary side magnetic coupling reactor 204 of the transformer 400 decreases. On the other hand, the ripple current I5 flowing in the capacitor C1 in the period T3 is overlapped with three kinds of current components (currents I2, I3, and I4).

  The current I2 flowing in the period T3 is a current component that discharges the capacitor C1 in order to reset the energy stored in the equivalent inductance L of the transformer 400 and the primary side magnetic coupling reactor 204. The current I1 approaches zero by the action of the current I2 flowing in the period T3. The current I3 flowing in the period T3 is a constant current component that discharges the capacitor C1 in a direction in which charges are discharged from the capacitor C1 to the load connected to the first input / output port PA1. The current I4 flowing in the period T3 is a current component that discharges the capacitor C1 in the direction in which charges are discharged from the capacitor C1 to the load connected to the second input / output port PC1 and the capacitor C3. The voltage of the first input / output port PA1 is stepped down to the voltage of the second input / output port PC1 by the current I4 flowing in the period T3.

  FIG. 9 shows a state where the voltage of the first input / output port PA1 is stepped down to the voltage of the second input / output port PC1 in the period T4 of FIG. In the period T4, the operation of transmitting power between the first input / output port PA1 and the third input / output port PB1 is not performed.

  The current component of the ripple current I5 flowing in the capacitor C1 during the period T4 is a constant discharge current I3 supplied from the capacitor C1 to the load connected to the first input / output port PA1. The current I4 flowing in the period T4 is discharged from the primary side coil 202 and the primary side magnetic coupling reactor 204 of the transformer 400 to the load connected to the second input / output port PC1 and the capacitor C3 in the direction of discharging the capacitor C1. Is a current component that discharges. The voltage of the first input / output port PA1 is stepped down to the voltage of the second input / output port PC1 by the current I4 flowing in the period T4.

  Thus, in a state where the power supply circuit is in a switching operation, in addition to the discharge current I3 always flowing from the capacitor C1 to the load of the first input / output port PA1, the capacitor C1 is a large current in the periods T2 and T3. Charge and discharge. Therefore, the effective value of the ripple current I5 tends to increase.

  Note that the control contents performed in the periods T5, T6, T7, and T8 in FIG. 5 are the same control states as those in the periods T1, T2, T3, and T4, respectively, and thus description thereof is omitted.

  Here, as shown in FIG. 5, the positive current peak of the ripple current I5 and the negative current peak of the ripple current I5 appear alternately every 90 ° in one cycle (360 °). . In FIG. 5, a positive current peak waveform in which current flows in the direction in which the capacitor C1 is charged is generated in the periods T2 and T6, and a negative current peak waveform in which current flows in the direction in which the capacitor C1 is discharged is in the periods T3 and T7. Is occurring.

  Therefore, the control circuit 50 has a control function for changing the phase of the switching waveform in the power conversion circuit unit among a plurality of power supply circuits in order to reduce the ripple current flowing in the capacitor connected to each input / output port. Yes. Thereby, for example, the waveform of the positive current peak generated by the power conversion circuit unit of the first power supply circuit among the plurality of power supply circuits and the power conversion circuit unit of the second power supply circuit among the plurality of power supply circuits The waveform of the negative current peak generated by can be brought close to each other so as to overlap each other.

  As a result, currents flowing in opposite directions flow through the capacitors to which the first power supply circuit and the second power supply circuit are connected together. As a result, the ripple current flowing through the capacitor can be reduced, so that the capacitor can be easily downsized. Further, by reducing the ripple current, for example, noise generated in the input / output port to which the capacitor is connected can be reduced, and the output accuracy of the input / output port can be improved.

  For example, the power conversion circuit 10 can convert power between any two of the four input / output ports PA, PB, PC, and PD to which the power supply circuits 11 and 12 are connected. Therefore, not only can the ripple current flowing in the capacitor C1 connected to the first input / output port PA be reduced, but also the capacitors C2, C3, C4 connected to the input / output ports PB, PC, PD other than the first input / output port PA. The ripple current flowing in the can also be reduced. Further, by reducing each ripple current, the capacitors C1, C2, C3, and C4 can be easily downsized, noise generated at the input / output ports PA, PB, PC, and PD can be reduced, and the input / output ports PA, PB, and PC can be reduced. , PD output accuracy can be improved.

  The control circuit 50 has the same phase between the power supply circuit 11 and the power supply circuit 12 so that the waveform of the positive current peak generated by the power supply circuit 11 and the waveform of the negative current peak generated by the power supply circuit 12 overlap. Control is performed to vary the switching timing between the power conversion circuit units by the phase difference ε. The phase difference ε is a switching timing shift (time lag) between the power conversion circuit units of the same phase between the power supply circuit 11 and the power supply circuit 12.

  For example, the control circuit 50 performs control to shift the switching timing of the primary side first arm circuit 207 of the power supply circuit 11 in phase with the switching timing of the primary side first arm circuit 207 of the power supply circuit 12. Similarly, the control circuit 50 shifts the switching timing of the primary side second arm circuit 211 of each of the power supply circuits 11 and 12 from each other, and sets the switching timing of the secondary side first arm circuit 307 of each of the power supply circuits 11 and 12 to each other. The switching timing of the secondary side second arm circuit 311 of each of the power supply circuits 11 and 12 is shifted from each other.

  FIG. 10 is a timing chart showing ON / OFF switching waveforms of the primary first upper arm U1 of the power supply circuit 11 and the primary first upper arm U1 of the power supply circuit 12. As shown in FIG. 10, the control circuit 50 causes the phase difference ε to occur in both switching waveforms of the primary first upper arm U1 of the power supply circuit 11 and the primary first upper arm U1 of the power supply circuit 12. These two arms are switched. For the switching waveforms of the other arms / U1, V1, / V1, U2, / U2, V2, and / V2, the control circuit 50 also has the same phase difference ε between the power supply circuit 11 and the power supply circuit 12 as that of the arm U1. Each arm is switched so that.

  The control circuit 50 may advance or delay the phase of the switching waveform of one power supply circuit relative to the switching waveform of the other power supply circuit.

  The control circuit 50 controls the phase of each switching waveform of the power supply circuits 11 and 12 so that the phase difference ε between the power supply circuit 11 and the power supply circuit 12 becomes a value within a predetermined range larger than zero. For example, the control circuit 50 adjusts the phase of the power supply circuits 11 and 12 so that the phase difference ε between the power supply circuit 11 and the power supply circuit 12 is 70 ° to 110 °, preferably 80 ° to 100 °. Control the phase of each switching waveform. By controlling the phase difference ε to a value within such a range, the ripple current flowing through the capacitor connected to each input / output port can be effectively reduced, and the capacitor can be easily downsized.

  FIG. 11 is a simulation waveform of the ripple current flowing in the capacitor C1 when the phase difference ε between the power supply circuit 11 and the power supply circuit 12 is zero. FIG. 12 is a simulation waveform of the ripple current flowing in the capacitor C1 when the phase difference ε between the power supply circuit 11 and the power supply circuit 12 is 90 °. In this way, the control circuit 50 can reduce the effective value (RMS) of the ripple current by 70% from a to b by performing switching control of each arm so that the phase difference ε becomes 90 °.

  As described above, the power supply circuit and the control method of the power supply circuit have been described in the embodiment. However, the present invention is not limited to the embodiment. Various modifications and improvements, such as combinations and substitutions with part or all of other example embodiments, are possible within the scope of the present invention.

  For example, in the above-described embodiment, as an example of the switching element, a MOSFET that is a semiconductor element that performs an on / off operation is described. However, the switching element may be, for example, a voltage-controlled power element using an insulated gate such as IGBT or MOSFET, or a bipolar transistor.

  In addition, a power source may be connected to the first input / output port PA, or a power source may be connected to the fourth input / output port PD. Further, the power source may not be connected to the second input / output port PC, and the power source may not be connected to the third input / output port PB.

  The capacitor provided in the port may be a capacitor other than a film capacitor, for example, an aluminum electrolytic capacitor or a solid polymer capacitor.

  Further, the number of power supply circuits in parallel may be three or more.

10 Power conversion circuit (an example of a power supply device)
11, 12 power supply circuit (an example of a first power supply circuit and a second power supply circuit)
20 Primary side conversion circuit 30 Secondary side conversion circuit 50 Control circuit 70 Sensor circuit 101 Power conversion circuit system 200 Primary side full bridge circuit 202 Primary side coil 204 Primary side magnetic coupling reactor 207 Primary side first arm circuit 211 Primary side second arm circuit 207m, 211m Middle point 298 Primary side positive electrode bus 299 Primary side negative electrode bus 300 Secondary side full bridge circuit 302 Secondary side coil 304 Secondary side magnetic coupling reactor 307 Secondary side first Arm circuit 311 Secondary side second arm circuit 307m, 311m Middle point 398 Secondary side positive bus 399 Secondary side negative bus 400 Transformer PA First input / output port PB Third input / output port PC Second input / output port PD First 4 I / O ports U *, V * Upper arm / U *, / V * Lower arm

Claims (4)

A primary side circuit; a secondary side circuit magnetically coupled to the primary side circuit by a transformer; and first and second ports of the primary side circuit and third and second sides of the secondary side circuit. Of the four ports including the fourth port, power is converted between any two ports by switching in a power conversion unit configured in each of the primary circuit and the secondary circuit. A power supply device including a power supply circuit in parallel and a capacitor provided in the four ports,
The power supply device, wherein a phase of a switching waveform in the power converter is different between the power supply circuits.   The phase is such that a positive current peak flowing in the capacitor by the first power supply circuit of the power supply circuit and a negative current peak flowing in the capacitor by the second power supply circuit of the power supply circuit approach each other. The power supply device according to claim 1, wherein   The power supply device according to claim 1 or 2, wherein the phase difference between the power supply circuits is 70 ° or more and 110 ° or less. A primary side circuit; a secondary side circuit magnetically coupled to the primary side circuit by a transformer; and first and second ports of the primary side circuit and third and second sides of the secondary side circuit. Of the four ports including the fourth port, power is converted between any two ports by switching in a power conversion unit configured in each of the primary circuit and the secondary circuit. A power supply device control method comprising a power supply circuit in parallel and a capacitor provided in the four ports,
A method for controlling a power supply apparatus, wherein the phase of a switching waveform in the power conversion unit is made different between the power supply circuits.

Images