Power converter
The power conversion device uses parallel-connected inputs and series-connected outputs of non-isolated DC-DC converter circuits with bidirectional elements to maintain constant voltage across a wide range, simplifying the circuit and enabling easier design and miniaturization.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- KK TOSHIBA
- Filing Date
- 2023-06-20
- Publication Date
- 2026-06-17
Smart Images
Figure 0007875157000005 
Figure 0007875157000006 
Figure 0007875157000007
Abstract
Description
Technical Field
[0001] This embodiment relates to a power conversion device.
Background Art
[0002] There is known a power conversion device that boosts or buck-boosts a DC input voltage and outputs it as a constant DC voltage. For example, a power conversion device using an LLC resonant converter circuit is known.
[0003] In the case of a power conversion device using an LLC resonant converter circuit, it is difficult to control the LLC resonant converter circuit alone to keep the output voltage constant over a wide range from a low output voltage to a high output voltage. Therefore, usually, a constant voltage circuit is provided in front of the LLC resonant converter circuit, and first, constant voltage control is performed by the first-stage constant voltage circuit, and then buck-boost is performed by the second-stage LLC resonant converter circuit.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] An object of this embodiment is to provide a power conversion device that can control the output voltage to be kept constant over a wide range from a low output voltage to a high output voltage.
Means for Solving the Problems
[0006] To solve the above problems, the power conversion device according to this embodiment includes a plurality of non-isolated DC-DC converter circuits including bidirectional elements, the inputs of the plurality of non-isolated DC-DC converter circuits are connected in parallel, and the outputs of the plurality of non-isolated DC-DC converter circuits are connected in series.
[0007] Furthermore, another power conversion device according to this embodiment includes a plurality of non-isolated DC-DC converter circuits including bidirectional elements, the inputs of the plurality of non-isolated DC-DC converter circuits are connected in series, and the outputs of the plurality of non-isolated DC-DC converter circuits are connected in parallel. [Brief explanation of the drawing]
[0008] [Figure 1] A diagram showing the configuration of a power conversion device according to Embodiment 1. [Figure 2] A diagram showing the detailed configuration of a non-isolated DC-DC converter circuit according to Embodiment 1. [Figure 3] A figure showing an example of the time waveforms of the first PWM control signal and the second PWM control signal according to Embodiment 1. [Figure 4] A diagram showing the on / off operation timings of each of the N non-isolated DC-DC converter circuits according to Embodiment 1. [Figure 5] A diagram showing the configuration of a power conversion device according to Embodiment 2. [Figure 6] A diagram showing the on / off operation timings of each of the N non-isolated DC-DC converter circuits according to Embodiment 2. [Figure 7] A diagram showing the configuration of a power conversion device according to Embodiment 3. [Figure 8] A diagram showing the detailed configuration of a non-isolated DC-DC converter circuit according to Embodiment 3. [Figure 9] A diagram showing the configuration of a power conversion device according to Embodiment 4. [Figure 10] A diagram showing the detailed configuration of a non-isolated DC-DC converter circuit according to Embodiment 4. [Modes for carrying out the invention]
[0009] This embodiment will be described below with reference to the drawings. In the drawings, the same or corresponding elements are denoted by the same reference numerals, and detailed descriptions are omitted as appropriate.
[0010] (Embodiment 1) Figure 1 shows the configuration of a power converter 100 according to Embodiment 1. The power converter 100 is a device that boosts a DC input voltage and outputs it as a constant DC voltage, and is equipped with input terminals INa and INb, and output terminals OUTa and OUTb. A DC input voltage Vin is applied to the input terminals INa and INb, and a DC output voltage Vo (>Vin) is output from the output terminals OUTa and OUTb.
[0011] The power converter 100 comprises N non-isolated DC-DC converter circuits 101(1) to 101(N) and a timing control circuit 102 that controls the operating timing of these N DC-DC converter circuits 101(1) to 101(N). The inputs of each DC-DC converter circuit 101(1) to 101(N) are connected in parallel, with one input connected to input terminal INa and the other to input terminal INb. The input voltage V1 of all DC-DC converter circuits 101(1) to 101(N) is equal, so V1 = Vin.
[0012] The outputs of the DC-DC converter circuits 101(1) to 101(N) are connected in series. One output of the uppermost DC-DC converter circuit 101(1) is connected to output terminal OUTa, and the other output of the lowermost DC-DC converter circuit 101(N) is connected to output terminal OUTb. The output voltage V2 of the DC-DC converter circuits 101(1) to 101(N) are all equal, and therefore V2 × N = Vo.
[0013] FIG. 2 is a diagram showing a detailed configuration of the non-insulated DC-DC converter circuit 101 according to Embodiment 1. Since the configurations of the DC-DC converter circuits 101(1) to 101(N) are all the same, they are collectively referred to as the DC-DC converter circuit 101.
[0014] The DC-DC converter circuit 101 includes a first input terminal 11a and a second input terminal 11b, a first output terminal 12a and a second output terminal 12b, a first bidirectional element 13 provided between the first input terminal 11a and the first output terminal 12a, and a second bidirectional element 14 provided between the second input terminal 11b and the second output terminal 12b.
[0015] The first bidirectional element 13 includes semiconductor switching elements M1 and M2. As the semiconductor switching elements M1 and M2, for example, N-channel MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) can be used. In this case, the source terminals and the gate terminals of the semiconductor switching elements M1 and M2 are connected to each other. The drain terminal of the semiconductor switching element M1 is connected to one terminal 13a of the first bidirectional element 13, and the drain terminal of the semiconductor switching element M2 is connected to the other terminal of the first bidirectional element 13.
[0016] When the control signal G1 supplied to the first bidirectional element 13 is on, the first bidirectional element 13 conducts in both directions. That is, current can flow in the right direction in the figure via the channel between the drain and source of the semiconductor switching element M1 and the parasitic diode of the semiconductor switching element M2, and current can also flow in the left direction in the figure via the channel between the drain and source of the semiconductor switching element M2 and the parasitic diode of the semiconductor switching element M1.
[0017] When the control signal G1 supplied to the first bidirectional element 13 is off, no current flows in either direction of the first bidirectional element 13. That is, the potential of one terminal 13a of the first bidirectional element 13 and the potential of the other terminal 13b are electrically separated.
[0018] The second bidirectional element 14 includes semiconductor switching elements M3 and M4. As the semiconductor switching elements M3 and M4, for example, N-channel MOSFETs can be used. In this case, the source terminals of the semiconductor switching elements M3 and M4 are connected to each other, and the gate terminals of the semiconductor switching elements M3 and M4 are connected to each other. The drain terminal of the semiconductor switching element M3 is connected to one terminal 14a of the second bidirectional element 14, and the drain terminal of the semiconductor switching element M4 is connected to the other terminal 14b of the second bidirectional element 14.
[0019] When the control signal G2 supplied to the second bidirectional element 14 is on, the second bidirectional element 14 conducts in both directions. That is, current can flow in the right direction in the figure via the channel between the drain and source of the semiconductor switching element M3 and the parasitic diode of the semiconductor switching element M4, and current can also flow in the left direction in the figure via the channel between the drain and source of the semiconductor switching element M4 and the parasitic diode of the semiconductor switching element M3.
[0020] When the control signal G2 supplied to the second bidirectional element 14 is off, no current flows in either direction of the second bidirectional element 14. That is, the potential of one terminal 14a of the second bidirectional element 14 and the potential of the other terminal 14b are electrically separated.
[0021] Also, the DC-DC converter circuit 101 includes a first inductor L1, a first unidirectional element D1, and a second unidirectional element D2. One end of the first inductor L1 is connected to a first node N1 between the first bidirectional element 13 and the first output terminal 12a, and the other end of the first inductor L1 is connected to a second node N2 between the second bidirectional element 14 and the second output terminal 12b.
[0022] For example, a semiconductor diode can be used as the first unidirectional element D1. In this case, the anode of the first unidirectional element D1 is connected to the first output terminal 12a, and the cathode of the first unidirectional element D1 is connected to the first node N1.
[0023] For example, a semiconductor diode can be used as the second unidirectional element D2. In this case, the anode of the second unidirectional element D2 is connected to the second node N2, and the cathode of the second unidirectional element D2 is connected to the second output terminal 12b.
[0024] Furthermore, the DC-DC converter circuit 101 includes a first capacitor C1 and a second capacitor C2. The first capacitor C1 is connected between the first input terminal 11a and the second input terminal 11b. The second capacitor C2 is connected between the first output terminal 12a and the second output terminal 12b.
[0025] Furthermore, the DC-DC converter circuit 101 includes a first voltage sensor 15, a second voltage sensor 16, a first current sensor 17, a first drive circuit 18, a second drive circuit 19, and a control circuit 20.
[0026] The first voltage sensor 15 detects the input voltage V1 (first voltage) of the DC-DC converter circuit 101. The second voltage sensor 16 detects the output voltage V2 (second voltage) of the DC-DC converter circuit 101. The first current sensor 17 detects the first current I1 flowing through the first inductor L1.
[0027] The first drive circuit 18 supplies a first PWM control signal G1 to the first bidirectional element 13. The second drive circuit 19 supplies a second PWM control signal G2 to the second bidirectional element 14. The control circuit 20 controls the operation of the first drive circuit 18 and the second drive circuit 19 based on the timing control signal TS input from the timing control circuit 102, the input voltage V1 and the output voltage V2, and the first current I1.
[0028] FIG. 3 is a diagram showing an example of the time waveforms of the first PWM control signal G1 and the second PWM control signal G2. The first PWM control signal G1 and the second PWM control signal G2 are controlled so as to have the same waveform that changes at the same timing. That is, the second PWM control signal G2 also turns on at the timing when the first PWM control signal G1 turns on, and the second PWM control signal G2 also turns off at the timing when the first PWM control signal G1 turns off. However, the voltage level of the first PWM control signal G1 is different from the voltage level of the second PWM control signal, and the GNDs of both are separated.
[0029] When both the first PWM control signal G1 and the second PWM control signal G2 turn on, both the first bidirectional element 13 and the second bidirectional element 14 become conductive states. At this time, current flows through the path of the first input terminal 11a, the first bidirectional element 13, the first inductor L1, the second bidirectional element 14, and the second input terminal 11b, and due to this current, magnetic energy is stored in the first inductor L1.
[0030] When both the first PWM control signal G1 and the second PWM control signal G2 turn off, both the first bidirectional element 13 and the second bidirectional element 14 become non-conductive states. At this time, due to the magnetic energy stored in the first inductor L1, current flows through the path of the first inductor L1, the second unidirectional element D2, the second output terminal 12b, the first output terminal 12a, and the first unidirectional element D1.
[0031] The control circuit 20 can control the output voltage V2 of the DC-DC converter circuit 101 to be kept constant by appropriately adjusting the duty ratio D (0 < D < 1) of the first PWM control signal G1 and the second PWM control signal G2.
[0032] For example, when input voltage V1 < output voltage V2, the DC-DC converter circuit 101 functions as a boost converter circuit. Also, for example, when input voltage V1 > output voltage V2, the DC-DC converter circuit 101 functions as a buck converter circuit.
[0033] Figure 4 shows the on / off operation timings of N non-isolated DC-DC converter circuits 101(1) to 101(N) according to this embodiment 1. The timing control circuit 102 controls the operation of the N DC-DC converter circuits 101(1) to 101(N) by repeating N time slots TS_1 to TS_N. In the figure, fsw is the switching frequency.
[0034] In the first time slot TS_1, only the first bidirectional element 13 and the second bidirectional element 14 of the first DC-DC converter circuit 101(1) are off, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all on.
[0035] In the second time slot TS_2, only the first bidirectional element 13 and the second bidirectional element 14 of the second DC-DC converter circuit 101(2) are off, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all on.
[0036] Similarly, in the Nth time slot TS_N, only the first bidirectional element 13 and the second bidirectional element 14 of the Nth DC-DC converter circuit 101(N) are off, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all on.
[0037] In this embodiment 1, the transformation ratio V2 / V1 of the DC-DC converter circuits 101(1) to 101(N) is all equal, and is D / (1-D). Therefore, the relationship between the input voltage Vin and the output voltage Vo of the power converter 100, which is configured by connecting N DC-DC converter circuits 101(1) to 101(N), is expressed as follows.
[0038]
number
[0039] As described above, the power converter 100 according to this embodiment 1 is equipped with a plurality of non-isolated DC-DC converter circuits 101 including bidirectional elements, the inputs of each DC-DC converter circuit 101 are connected in parallel, and the outputs of each DC-DC converter circuit 101 are connected in series.
[0040] As mentioned earlier, in the case of power conversion devices using conventional LLC resonant converter circuits, for example, it was difficult to control the output voltage to remain constant over a wide range from low to high output voltages using the LLC resonant converter circuit alone. Therefore, it was common practice to first install a constant voltage circuit before the LLC resonant converter circuit, performing constant voltage control with the first-stage constant voltage circuit, and then performing step-up / step-down voltage control with the second-stage LLC resonant converter circuit.
[0041] In contrast, the power converter 100 according to this embodiment 1 connects multiple non-isolated DC-DC converter circuits 101 that combine constant voltage control and step-up / step-down functions, allowing for a simpler circuit configuration than conventional technology, while maintaining a constant output voltage V2 over a wide range from low to high output voltages. Furthermore, since any desired output voltage V2 can be obtained by adjusting the number of DC-DC converter circuits 101, it offers excellent expandability.
[0042] Furthermore, in the power converter 100 according to this embodiment 1, a high transformation ratio is achieved not by a single DC-DC converter circuit, but by connecting multiple DC-DC converter circuits 101. Therefore, the transformation ratio of each DC-DC converter circuit 101 may be low. As a result, by appropriately adjusting the number N of DC-DC converter circuits 101, it is possible to set the duty cycle D of each DC-DC converter circuit 101 to around 0.5, and it is possible to provide a margin in the on / off time of the PWM control of each DC-DC converter circuit 101. This makes it easier to increase the switching frequency fsw and allows the first inductor L1 to be relatively small.
[0043] Furthermore, the on / off operation of the non-isolated DC-DC converter circuit 101 according to this embodiment 1 can be controlled by PWM control, similar to that of a typical buck-boost chopper circuit. In addition, components such as transformers and snubbers, which are required in conventional non-isolated flyback circuits, are unnecessary. This makes design and control extremely easy.
[0044] Furthermore, the non-isolated DC-DC converter circuit 101 according to this embodiment 1 includes a first bidirectional element 13 and a second bidirectional element 14. The first bidirectional element 13 is composed of two semiconductor switching elements M1 and M2. The second bidirectional element 14 is composed of two semiconductor switching elements M3 and M4. In the off state of the DC-DC converter circuit 101, the input potential and output potential are electrically isolated by the parasitic capacitance between the drain and source of the semiconductor switching elements.
[0045] In contrast, in a conventional LLC resonant converter circuit, the input potential and the output potential in the on-state and the off-state are electrically separated by a high-frequency transformer. The high-frequency transformer is a component that occupies a large area on the circuit and can also increase the man-hours required for circuit design. In the non-insulated DC-DC converter circuit 101 according to the first embodiment, since there is no need to use a high-frequency transformer, miniaturization of the circuit area and reduction of the man-hours required for design can be expected.
[0046] (Embodiment 2) FIG. 5 is a diagram showing the configuration of a power conversion device 200 according to the second embodiment. The power conversion device 200 is a device that steps down a DC input voltage and outputs it as a constant DC voltage. A DC input voltage Vin is applied to input terminals INa and INb, and a DC output voltage Vo (<Vin) is output from output terminals OUTa and OUTb.
[0047] The power conversion device 200 includes N non-insulated DC-DC converter circuits 101(1) to 101(N) having the same configuration as that of the first embodiment described above. The power conversion device 200 also includes a timing control circuit 202 that controls the operation timing of these N DC-DC converter circuits 101(1) to 101(N).
[0048] The inputs of the DC-DC converter circuits 101(1) to 101(N) are connected in series. One input of the uppermost DC-DC converter circuit 101(1) is connected to the input terminal INa, and the other input of the lowermost DC-DC converter circuit 101(N) is connected to the input terminal INb. The input voltages V1 of the DC-DC converter circuits 101(1) to 101(N) are all equal, and thus, V1 = Vin / N.
[0049] The outputs of DC-DC converter circuits 101(1) to 101(N) are connected in parallel, with one output connected to output terminal OUTa and the other to output terminal OUTb. The output voltage V2 of DC-DC converter circuits 101(1) to 101(N) is all equal, so V2 = Vo.
[0050] Figure 6 shows the on / off operation timings of N non-isolated DC-DC converter circuits 101(1) to 101(N) according to this second embodiment. The timing control circuit 202 controls the operation of the N DC-DC converter circuits 101(1) to 101(N) by repeating N time slots TS_1 to TS_N.
[0051] In the first time slot TS_1, only the first bidirectional element 13 and the second bidirectional element 14 of the first DC-DC converter circuit 101(1) are turned on, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all turned off.
[0052] In the second time slot TS_2, only the first bidirectional element 13 and the second bidirectional element 14 of the second DC-DC converter circuit 101(2) are turned on, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all turned off.
[0053] Similarly, in the Nth time slot TS_N, only the first bidirectional element 13 and the second bidirectional element 14 of the Nth DC-DC converter circuit 101(N) are turned on, while the first bidirectional elements 13 and the second bidirectional elements 14 of the other N-1 DC-DC converter circuits are all turned off.
[0054] In this second embodiment, the transformation ratio V2 / V1 of the DC-DC converter circuits 101(1) to 101(N) is all equal, and is D / (1-D). In this case, the relationship between the input voltage Vin and the output voltage Vo of the power converter 200, which is configured by connecting N DC-DC converter circuits 101(1) to 101(N), is expressed as follows.
[0055]
number
[0056] As described above, the power converter 200 according to this second embodiment includes a plurality of non-isolated DC-DC converter circuits 101 including bidirectional elements, with the inputs of each DC-DC converter circuit 101 connected in series and the outputs of each DC-DC converter circuit 101 connected in parallel. As a result, the power converter 200 according to this second embodiment can obtain the same effects as those of the first embodiment described above.
[0057] (Embodiment 3) Figure 7 shows the configuration of the power converter 300 according to Embodiment 3. The power converter 300 is the same as the power converter 100 according to Embodiment 1 described above, but with N non-isolated DC-DC converter circuits 101 to 101(N) replaced by N non-isolated DC-DC converter circuits 301(1) to 301(N). The power converter 300 boosts the DC input voltage and outputs it as a constant DC voltage. The on / off operation timing of each DC-DC converter circuit 301(1) to 301(N) is the same as in Embodiment 1 described above.
[0058] Figure 8 shows the detailed configuration of the non-isolated DC-DC converter circuit 301 according to this third embodiment. Note that the configurations of DC-DC converter circuits 301(1) to 301(N) are all the same, and are therefore collectively referred to as DC-DC converter circuit 301.
[0059] The DC-DC converter circuit 301 includes a first bidirectional element 13 provided between a first input terminal 11a and a first output terminal 12a, and a second bidirectional element 14 provided between a second input terminal 11b and a second output terminal 12b.
[0060] Furthermore, the DC-DC converter circuit 301 includes a second inductor L2, a second current sensor 321, and a semiconductor switching element M5. The second inductor L2 is connected between the first input terminal 11a and the first bidirectional element 13. The second current sensor 321 detects the second current I2 flowing through the second inductor L2.
[0061] For example, an N-channel MOSFET can be used as the semiconductor switching element M5. In this case, the drain terminal of the semiconductor switching element M5 is connected to a third node N3 between the second inductor L2 and the first bidirectional element 13, and the source terminal of the semiconductor switching element M5 is connected to a fourth node N4 between the second input terminal 11b and the second bidirectional element 14.
[0062] The control circuit 220 controls the operation of the first drive circuit 18 and the second drive circuit 19 based on the timing control signal TS, input voltage V1 and output voltage V2, and the second current I2 input from the timing control circuit 102.
[0063] In this third embodiment, the transformation ratio V2 / V1 of the DC-DC converter circuits 301(1) to 301(N) is all equal, which is 1 / (1-D). Therefore, V2 > V1 is always true. The relationship between the input voltage Vin and output voltage Vo of the power converter 300 is expressed as follows.
[0064]
number
[0065] (Embodiment 4) Figure 9 shows the configuration of the power converter 400 according to Embodiment 4. The power converter 400 is the same as the power converter 200 according to Embodiment 2 described above, but with N non-isolated DC-DC converter circuits 101 to 101(N) replaced by N non-isolated DC-DC converter circuits 401(1) to 401(N). The power converter 400 steps down the DC input voltage and outputs it as a constant DC voltage. The on / off operation timing of each DC-DC converter circuit 401(1) to 401(N) is the same as in Embodiment 2 described above.
[0066] Figure 10 shows the detailed configuration of the non-isolated DC-DC converter circuit 401 according to this embodiment 4. Note that the configurations of DC-DC converter circuits 401(1) to 401(N) are all the same, and are therefore collectively referred to as DC-DC converter circuit 401.
[0067] The DC-DC converter circuit 401 includes a first bidirectional element 13 provided between a first input terminal 11a and a first output terminal 12a, and a second bidirectional element 14 provided between a second input terminal 11b and a second output terminal 12b.
[0068] Furthermore, the DC-DC converter circuit 401 includes a third inductor L3, a third current sensor 422, and a third unidirectional element D3. The third inductor L3 is connected between the first bidirectional element 13 and the first output terminal 12a. The third current sensor 422 detects the third current I3 flowing through the third inductor L3.
[0069] For example, a semiconductor diode can be used as the third unidirectional element D3. In this case, the cathode of the third unidirectional element D3 is connected to the fifth node N5 between the first bidirectional element 13 and the third inductor L3, and the anode of the third unidirectional element D3 is connected to the sixth node N6 between the second bidirectional element 14 and the second output terminal 12b.
[0070] The control circuit 420 controls the operations of the first drive circuit 18 and the second drive circuit 19 based on the timing control signal TS input from the timing control circuit 202, the input voltage V1 and the output voltage V2, and the third current I3.
[0071] In the fourth embodiment, the voltage conversion ratios V2 / V1 of the DC-DC converter circuits 401(1) to 401(N) are all equal to D. Therefore, V2 < V1 always holds. The relationship between the input voltage Vin and the output voltage Vo of the power conversion device 400 is expressed as follows.
[0072]
Equation
[0073] (Modification example) In the above first to fourth embodiments, N-channel MOSFETs have been used as the semiconductor switching elements M1 to M5. Instead of this, P-channel MOSFETs may be used as the semiconductor switching elements M1 to M5.
[0074] In the above first to fourth embodiments, semiconductor diodes have been used as the unidirectional elements D1 to D3. Instead of this, synchronous rectification may be performed by using semiconductor switching elements such as MOSFETs as the unidirectional elements D1 to D3. Alternatively, a configuration in which two semiconductor switching elements similar to the bidirectional elements 13 or 14 are connected may be used as the unidirectional elements D1 to D3. By these means, heat generation of the unidirectional elements D1 to D3 can be suppressed.
[0075] Furthermore, semiconductor switching elements are not limited to MOSFETs. For example, IGBTs (Insulated Gate Bipolar Transistors) or BJTs (Bipolar Junction Transistors) may be used as semiconductor switching elements. In addition, various materials such as Si (Silicon), SiC (Silicon Carbide), or GaN (Gallium Nitride) can be used as semiconductors constituting semiconductor switching elements and semiconductor diodes.
[0076] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the embodiments. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the embodiments. These embodiments and their variations are included in the scope and spirit of the embodiments, as well as in the claims and their equivalents.
[0077] Furthermore, this embodiment can also be configured as follows. [Item 1] (Actual 1, Actual 3) It features multiple non-isolated DC-DC converter circuits including bidirectional elements, A power conversion device in which the inputs of the plurality of non-isolated DC-DC converter circuits are connected in parallel, and the outputs of the plurality of non-isolated DC-DC converter circuits are connected in series. [Item 2] (Actual 1, Actual 3) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first input terminal and a second input terminal, The first output terminal and the second output terminal, A first bidirectional element provided between the first input terminal and the first output terminal, A second bidirectional element provided between the second input terminal and the second output terminal, Power converters as described in item 1, including those listed in item 1. [Item 3] (Actual 1, Actual 3) Each of the first bidirectional element and the second bidirectional element includes a first semiconductor switching element and a second semiconductor switching element, The power conversion device according to item 2, wherein the first terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other, and the control terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other. [Item 4] (Practical 1) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: The power converter according to item 2 or 3, further comprising a first inductor, one end of which is connected to a first node between the first bidirectional element and the first output terminal, and the other end of which is connected to a second node between the second bidirectional element and the second output terminal. [Item 5] (Practical 1) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first unidirectional element, one end of which is connected to the first output terminal and the other end of which is connected to the first node, A second unidirectional element, one end of which is connected to the second node and the other end of which is connected to the second output terminal, The power converters described in item 4, further including the power converters described in item 4. [Item 6] (Practical 1) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first drive circuit that supplies a first PWM control signal to the first bidirectional element, A second drive circuit that supplies a second PWM control signal to the second bidirectional element, A control circuit that controls the operation of the first drive circuit and the second drive circuit, A power converter as described in any one of items 2 to 5, further including the following: [Item 7] (Practical 1) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first voltage sensor for detecting a first voltage between the first input terminal and the second input terminal, A second voltage sensor for detecting a second voltage between the first output terminal and the second output terminal, A first current sensor for detecting the first current flowing through the first inductor and It further includes, The power converter according to item 6, wherein the control circuit controls the operation of the first drive circuit and the second drive circuit based on the first voltage and the second voltage, and the first current. [Item 8] (Practical 1) The number of the aforementioned multiple non-isolated DC-DC converter circuits is N, and the system further comprises a timing control circuit that controls the operating timing of the N DC-DC converter circuits by repeating N time slots. In the first time slot, only the first DC-DC converter circuit is off, and all other N-1 DC-DC converter circuits are on. In the second time slot, only the second DC-DC converter circuit is off, while all the other N-1 DC-DC converter circuits are on. The following power converters, as described in item 7, are controlled similarly. [Item 9] (Actual 3) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A second inductor connected between the first input terminal and the first bidirectional element, A third switching element, one end of which is connected to a third node between the second inductor and the first bidirectional element, and the other end of which is connected to a fourth node between the second input terminal and the second bidirectional element, and A power converter as described in item 2 or 3, further including the power converter described in item 2 or 3. [Item 10] (Actual 2, Actual 4) It features multiple non-isolated DC-DC converter circuits including bidirectional elements, A power conversion device in which the inputs of the plurality of non-isolated DC-DC converter circuits are connected in series, and the outputs of the plurality of non-isolated DC-DC converter circuits are connected in parallel. [Item 11] (Actual 2, Actual 4) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first input terminal and a second input terminal, The first output terminal and the second output terminal, A first bidirectional element provided between the first input terminal and the first output terminal, A second bidirectional element provided between the second input terminal and the second output terminal, Power converters as described in item 10, including those listed in item 10. [Item 12] Actual 2, Actual 4) Each of the first bidirectional element and the second bidirectional element includes a first semiconductor switching element and a second semiconductor switching element, The power conversion device according to item 11, wherein the first terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other, and the control terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other. [Item 13] (Actual 2) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: The power converter according to item 11 or 12, further comprising a first inductor, one end of which is connected to a first node between the first bidirectional element and the first output terminal, and the other end of which is connected to a second node between the second bidirectional element and the second output terminal. [Item 14] (Actual 2) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first unidirectional element, one end of which is connected to the first output terminal and the other end of which is connected to the first node, A second unidirectional element, one end of which is connected to the second node and the other end of which is connected to the second output terminal, The power converters described in item 13, further including the power converters described in item 13. [Item 15] (Practical 2) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first drive circuit that supplies a first PWM control signal to the first bidirectional element, A second drive circuit that supplies a second PWM control signal to the second bidirectional element, A control circuit that controls the operation of the first drive circuit and the second drive circuit, A power converter as described in any one of items 11 to 14, further including the following: [Item 16] (Actual 2) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A first voltage sensor for detecting a first voltage between the first input terminal and the second input terminal, A second voltage sensor for detecting a second voltage between the first output terminal and the second output terminal, A first current sensor for detecting the first current flowing through the first inductor and It further includes, The power conversion device according to claim 15, wherein the control circuit controls the operation of the first drive circuit and the second drive circuit based on the first voltage and the second voltage and the first current. [Item 17] (Actual 2) The number of the aforementioned multiple non-isolated DC-DC converter circuits is N, and the system further comprises a timing control circuit that controls the operating timing of the N DC-DC converter circuits by repeating N time slots. In the first time slot, only the first DC-DC converter circuit is on, and all other N-1 DC-DC converter circuits are off. In the second time slot, only the second DC-DC converter circuit is on, and all other N-1 DC-DC converter circuits are off. The power converter described in item 16 is controlled similarly below. [Item 18] (Actual 4) Each of the aforementioned multiple non-isolated DC-DC converter circuits is: A third inductor connected between the first bidirectional element and the first output terminal, A third unidirectional element, one end of which is connected to a fifth node between the first bidirectional element and the third inductor, and the other end of which is connected to a sixth node between the second bidirectional element and the second output terminal. Power converters as described in item 11 or 12, further including: [Explanation of Symbols]
[0078] 11a First input terminal 11b Second input terminal 12a First output terminal 12b Second output terminal 13 First bidirectional element 13a One terminal 13b The other terminal 14. Second bidirectional element 14a One terminal 14b The other terminal 15. First voltage sensor 16. Second voltage sensor 17. First current sensor 18. First drive circuit 19. Second drive circuit 20 Control circuits 100 Power converter 101 DC-DC Converter Circuit 102 Timing control circuit 200 Power converter 202 Timing control circuit 300 Power converter 301 DC-DC Converter Circuit 320 Control circuits 321 Second current sensor 400 Power converter 401 DC-DC Converter Circuit 420 Control circuits 422 Third current sensor C1 First Capacitor C2 Second Capacitor D duty cycle D1 First unidirectional element D2 Second unidirectional element D3 Third unidirectional element fsw switching frequency G1 First PWM control signal G2 Second PWM control signal L1 First inductor L2 Second inductor L3 Third Inductor M1 Semiconductor switching element (first semiconductor switching element) M2 Semiconductor Switching Element (Second Semiconductor Switching Element) M3 Semiconductor switching element (first semiconductor switching element) M4 Semiconductor Switching Element (Second Semiconductor Switching Element) M5 Semiconductor Switching Element (Third Semiconductor Switching Element) N1 First node N2, the second node N3, the third node N4, the fourth node N5, the fifth node N6, the 6th node I1 First current I2 Second current I3 Third Current INa Input Terminal INb Input terminal OUTa Output terminal OUTb output terminal TS timing control signal V1 First voltage V2 Second voltage
Claims
1. It comprises N non-isolated DC-DC converter circuits including bidirectional elements, A power conversion device in which the inputs of the N non-isolated DC-DC converter circuits are connected in parallel, and the outputs of the N non-isolated DC-DC converter circuits are connected in series, Each of the N non-isolated DC-DC converter circuits is: A first input terminal and a second input terminal, A first output terminal and a second output terminal, A first bidirectional element provided between the first input terminal and the first output terminal, A second bidirectional element provided between the second input terminal and the second output terminal, A first drive circuit that supplies a first PWM control signal to the first bidirectional element, A second drive circuit that supplies a second PWM control signal to the second bidirectional element, A control circuit controls the operation of the first drive circuit and the second drive circuit such that when the first PWM control signal and the second PWM control signal are turned on at the same timing, both the first bidirectional element and the second bidirectional element become conductive, and when the first PWM control signal and the second PWM control signal are turned off at the same timing, both the first bidirectional element and the second bidirectional element become non-conductive. Includes, The system further comprises a timing control circuit that controls the operating timing of the N non-isolated DC-DC converter circuits by repeating N time slots, In the first time slot, only the first bidirectional element and the second bidirectional element of the first DC-DC converter circuit are in the non-conductive state, while the first bidirectional element and the second bidirectional element of the other N-1 DC-DC converter circuits are all in the conductive state. In the second time slot, only the first bidirectional element and the second bidirectional element of the second DC-DC converter circuit are in the non-conductive state, while the first bidirectional element and the second bidirectional element of the other N-1 DC-DC converter circuits are all in the conductive state. The following power converters are controlled in a similar manner.
2. Each of the first bidirectional element and the second bidirectional element includes a first semiconductor switching element and a second semiconductor switching element, The power conversion device according to claim 1, wherein the first terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other, and the control terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other.
3. Each of the N non-isolated DC-DC converter circuits is: The power conversion device according to claim 1, further comprising a first inductor, one end of which is connected to a first node between the first bidirectional element and the first output terminal, and the other end of which is connected to a second node between the second bidirectional element and the second output terminal.
4. Each of the N non-isolated DC-DC converter circuits is: A first unidirectional element, one end of which is connected to the first output terminal and the other end of which is connected to the first node, A second unidirectional element, one end of which is connected to the second node and the other end of which is connected to the second output terminal, The power conversion device according to claim 3, further comprising:
5. Each of the N non-isolated DC-DC converter circuits is: A first voltage sensor for detecting a first voltage between the first input terminal and the second input terminal, A second voltage sensor for detecting a second voltage between the first output terminal and the second output terminal, A first current sensor for detecting the first current flowing through the first inductor and It further includes, The power conversion device according to claim 3, wherein the control circuit controls the operation of the first drive circuit and the second drive circuit based on the first voltage and the second voltage and the first current.
6. Each of the N non-isolated DC-DC converter circuits is: A second inductor connected between the first input terminal and the first bidirectional element, A third switching element, one end of which is connected to a third node between the second inductor and the first bidirectional element, and the other end of which is connected to a fourth node between the second input terminal and the second bidirectional element, and The power conversion device according to claim 1, further comprising:
7. It comprises N non-isolated DC-DC converter circuits including bidirectional elements, A power conversion device in which the inputs of the N non-isolated DC-DC converter circuits are connected in series, and the outputs of the N non-isolated DC-DC converter circuits are connected in parallel, Each of the N non-isolated DC-DC converter circuits is: A first input terminal and a second input terminal, A first output terminal and a second output terminal, A first bidirectional element provided between the first input terminal and the first output terminal, A second bidirectional element provided between the second input terminal and the second output terminal, A first drive circuit that supplies a first PWM control signal to the first bidirectional element, A second drive circuit that supplies a second PWM control signal to the second bidirectional element, A control circuit controls the operation of the first drive circuit and the second drive circuit such that when the first PWM control signal and the second PWM control signal are turned on at the same timing, both the first bidirectional element and the second bidirectional element become conductive, and when the first PWM control signal and the second PWM control signal are turned off at the same timing, both the first bidirectional element and the second bidirectional element become non-conductive. Includes, The system further comprises a timing control circuit that controls the operating timing of the N non-isolated DC-DC converter circuits by repeating N time slots, In the first time slot, only the first bidirectional element and the second bidirectional element of the first DC-DC converter circuit are in the conductive state, while the first bidirectional element and the second bidirectional element of the other N-1 DC-DC converter circuits are all in the non-conductive state. In the second time slot, only the first bidirectional element and the second bidirectional element of the second DC-DC converter circuit are in the conductive state, while the first bidirectional element and the second bidirectional element of the other N-1 DC-DC converter circuits are all in the non-conductive state. The following power converters are controlled in a similar manner.
8. Each of the first bidirectional element and the second bidirectional element includes a first semiconductor switching element and a second semiconductor switching element, The power conversion device according to claim 7, wherein the first terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other, and the control terminals of the first semiconductor switching element and the second semiconductor switching element are connected to each other.
9. Each of the N non-isolated DC-DC converter circuits is: The power conversion device according to claim 7, further comprising a first inductor, one end of which is connected to a first node between the first bidirectional element and the first output terminal, and the other end of which is connected to a second node between the second bidirectional element and the second output terminal.
10. Each of the N non-isolated DC-DC converter circuits is: A first unidirectional element, one end of which is connected to the first output terminal and the other end of which is connected to the first node, A second unidirectional element, one end of which is connected to the second node and the other end of which is connected to the second output terminal, The power conversion device according to claim 9, further comprising:
11. Each of the N non-isolated DC-DC converter circuits is: A first voltage sensor for detecting a first voltage between the first input terminal and the second input terminal, A second voltage sensor for detecting a second voltage between the first output terminal and the second output terminal, A first current sensor for detecting the first current flowing through the first inductor and It further includes, The power conversion device according to claim 9, wherein the control circuit controls the operation of the first drive circuit and the second drive circuit based on the first voltage and the second voltage and the first current.
12. Each of the N non-isolated DC-DC converter circuits is: A third inductor connected between the first bidirectional element and the first output terminal, A third unidirectional element, one end of which is connected to a fifth node between the first bidirectional element and the third inductor, and the other end of which is connected to a sixth node between the second bidirectional element and the second output terminal. The power conversion device according to claim 7, further comprising: