Converter and method for operating a converter

Abstract

A converter (300) is disclosed which is designed to receive an input voltage (350) and to output an output voltage (360). The converter has a plurality of switches (371,..., 387). The converter also has a control unit which is connected to the plurality of switches, wherein the control unit is designed to control the plurality of switches of the converter using input parameters or output parameters based on data in a database. A method for operating a converter is disclosed. The method has: controlling the plurality of switches using input parameters or output parameters based on data in a database using a control unit which is connected to the plurality of switches of the converter.

Description

Technical Field

[0001] This disclosure relates to a converter and a method for operating the converter. Background Technology

[0002] Electric vehicles (EVs) use converters, such as DC / DC converters, to transfer energy between a low-voltage battery / low-voltage grid and a battery with a higher voltage. These DC / DC converters are also used to charge the vehicle's battery on the grid. Due to the trend towards vehicle electrification, there is a greater need for DC / DC converters that can not only transfer more power, but also achieve this even with the same or even smaller mechanical dimensions. Therefore, it is essential to increase the power density (kW / m²) of DC / DC converters. 3 ).

[0003] Higher power density can be achieved using either a PSFB (Phase-Shifted Full Bridge) or a DAB (Dual-Active Bridge) topology. These new topologies provide higher power density by turning semiconductor switches on and off in a way that reduces "switching losses" to zero. This technique is called Zero-Voltage Switching (ZVS).

[0004] During operation, existing PSFB / DAB implementations cannot guarantee ZVS due to instability in the construction of the DC / DC converter and / or the load used during operation. Therefore, in the case of these existing converters, the use of regulation loops and multiple sensors to ensure ZVS increases the cost of the converter.

[0005] Implementations based on PSFB or DAB are not exempt from protection requirements such as protection against undervoltage, overvoltage, overcurrent, short circuits, and other accidents. These protection requirements necessitate additional components (such as sensors), which may increase the final cost of the product.

[0006] Therefore, there is a need for an improved converter that can reduce the necessity and manufacturing cost of these additional components. Summary of the Invention

[0007] This disclosure relates to a converter. The converter can be designed to receive an input voltage and output an output voltage. The converter may have multiple switches. The converter may also have a control unit connected to the multiple switches, wherein the control unit is designed to control the multiple switches of the converter based on data in a database, using the input or output parameters of the converter.

[0008] This disclosure also relates to a method for operating a converter. The method may include: when using a control unit connected to a plurality of switches of the converter, controlling the plurality of switches based on data in a database, using input or output parameters of the converter. Attached Figure Description

[0009] In the following description, various embodiments of the present disclosure are described with reference to the following figures, wherein:

[0010] Figure 1 Block circuit diagrams of converter 100 according to various embodiments are illustrated.

[0011] Figure 2 Block circuit diagrams of converter 200 according to various embodiments are illustrated.

[0012] Figure 3 The schematic diagrams of the converter 300 according to various implementation methods are explained;

[0013] Figure 4 A diagram 400 illustrates a first gating signal 410 and a second gating signal 420 having a phase shift 430 according to various embodiments. Detailed Implementation

[0014] The following detailed description depicts specific details and embodiments in which the invention can be practically applied. These embodiments are described in sufficient detail to enable those skilled in the art to implement the invention. Other embodiments and modifications may be used without departing from the scope of the invention. The various embodiments are not necessarily mutually exclusive, as some embodiments may be combined with one or more embodiments to form new embodiments.

[0015] Features described in connection with one embodiment can be correspondingly applied to the same or similar features in other embodiments. Features described in connection with one embodiment can be correspondingly applied to other embodiments, even if not explicitly described in those other embodiments. Additions and / or combinations and / or substitutions described for features in connection with one embodiment can also be correspondingly applied to the same or similar features in other embodiments.

[0016] The invention described herein can be suitably applied without any element or any limitation not specifically disclosed herein. Therefore, the terms “comprising,” “having,” “including,” etc., have a broad meaning and are not limiting. Thus, the word “comprising,” or variations thereof such as “including” or “containing,” are considered to mean including the stated integers or groups of integers, but do not imply exclusion of any other integers or groups of integers. Furthermore, the terms and expressions used herein are used as descriptive rather than restrictive terms, and their use is not intended to exclude any equivalents of the shown and described features or portions thereof; however, it should be recognized that various modifications are possible within the claimed scope of the invention. Therefore, it should be understood that although the invention has been disclosed specifically by way of exemplary embodiments and optional features, those skilled in the art can utilize modifications and variations of the invention disclosed herein; and such modifications and variations are considered to be within the scope of the invention.

[0017] Figure 1 Block circuit diagrams of converter 100 according to various embodiments are illustrated.

[0018] According to various embodiments, converter 100 may have a primary converter 110. In various embodiments, converter 100 may have an alternating current grid 120. In various embodiments, converter 100 may have a secondary converter 130. In various embodiments, converter 100 may have a control unit 140. For example, the primary converter 110 may be a DC-AC converter and the secondary converter 130 may be an AC-DC converter.

[0019] In some embodiments, the primary converter 110 may have multiple switches. In various embodiments, the multiple switches may be field-effect transistors (FETs), such as metal-oxide-semiconductor field-effect transistors (MOSFETs). In some embodiments, the multiple switches may be insulated-gate bipolar transistors (IGBTs).

[0020] In various implementations, the alternating power grid 120 can be electrically coupled to the primary converter 110.

[0021] In various implementations, the secondary converter 130 can be electrically coupled to the alternating power grid 120.

[0022] In various embodiments, the secondary converter 130 may have a plurality of switches. In various embodiments, the plurality of switches may be field-effect transistors (FETs), such as metal-oxide-semiconductor field-effect transistors (MOSFETs). In some embodiments, the plurality of switches may be insulated-gate bipolar transistors (IGBTs).

[0023] In various embodiments, the control unit 140 may be wired logic circuitry or programmable logic circuitry, such as a programmable processor. The control unit may also be a processor that executes software, such as any type of computer program, firmware, or any combination thereof stored in memory.

[0024] In various embodiments, the control unit 140 may be connected to the plurality of switches. In various embodiments, the plurality of switches may be present in the primary converter 110 and / or the secondary converter 130.

[0025] In various embodiments, the control unit 140 may be designed to control multiple switches of the converter 100 based on data in a database, provided that the input or output parameters of the converter 100 are used. In various embodiments, the database may be a lookup table. This lookup table may be implemented programmatically as a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), or any other suitable device.

[0026] In various embodiments, the alternating power grid 120 may have a transformer or such a transformer. In various embodiments, the alternating power grid 120 may have a primary side and a secondary side. The primary side of the alternating power grid 120 may be electrically coupled to a primary converter 110. The secondary side of the alternating power grid 120 may be electrically coupled to a secondary converter 130.

[0027] In various embodiments, the converter 100 may be a DC-DC converter. This DC-DC converter may be an electronic circuit capable of receiving a first DC voltage level at its input and converting that first DC voltage level into a second DC voltage level at its output, wherein the second voltage level is preferably different from the first voltage level.

[0028] Figure 2Block diagrams of converter 200 according to various embodiments are illustrated. Converter 200 may have a primary converter 210. Converter 200 may have an alternating current grid 220. Converter 200 may have a secondary converter 230. Converter 200 may also have a control unit (not shown).

[0029] In various implementations, the primary converter 210 may be designed to receive an input voltage from the power supply 250.

[0030] In various implementations, power supply 250 can be a DC power supply. The input voltage can be a DC voltage. The input voltage can be between 250 V and 450 V.

[0031] In various implementations, the secondary converter 230 can be designed to output an output voltage. This output voltage can be a DC voltage. The output voltage can be lower than the input voltage. The output voltage can be between 20 V and 40 V.

[0032] In various embodiments, the secondary converter 230 may be connected to a load 260. The load 260 may be, for example, a DC load. In various embodiments, the secondary converter 230 may be designed to output the output voltage to the load 260.

[0033] Alternatively, the secondary converter 230 can be designed to receive the input voltage from the power supply 250.

[0034] In various implementations, power supply 250 can be a DC power supply. The input voltage can be a DC voltage.

[0035] In various implementations, the primary converter 210 can be designed to output an output voltage. This output voltage can be a DC voltage.

[0036] In various embodiments, the primary converter 210 may be connected to a load 260. The load 260 may be, for example, a DC load. In various embodiments, the primary converter 210 may be designed to output the output voltage to the load 260.

[0037] The converter 200 can be a bidirectional converter. For example, in operating mode, the secondary converter 230 can receive a DC voltage as input, the DC side of the primary converter 210 (which is not connected to the AC power grid 220) can be used as the output, and the circuit connected to the DC side of the primary converter 210 can be used as a load. In another operating mode, the primary converter 210 can receive a DC voltage as input, the DC side of the secondary converter 230 (which is not connected to the AC power grid 220) can be used as the output, and the voltage connected to the DC side of the secondary converter 230 can be used as a load. Although Figure 2 The example was used to describe the bidirectionality of the converter, but this disclosure is not limited thereto.

[0038] In various embodiments, the description of converter 100 also applies to converter 200.

[0039] Figure 3 The schematic diagrams of the converter 300 according to various implementation methods are explained.

[0040] According to various embodiments, converter 300 may have a primary converter 310. Converter 300 may have an alternating current grid 320. Converter 300 may have a secondary converter 330. Converter 300 may also have a control unit (not shown) that controls the switches. The control unit may be connected to the control terminals of the transistors (terminals not shown).

[0041] In various implementations, the primary converter 310 can be designed to receive an input voltage from a power supply 250. The power supply 250 can be a DC power supply. The input voltage can be a DC voltage.

[0042] In various implementations, the secondary converter 330 can be designed to output an output voltage. This output voltage can be a DC voltage. The secondary converter 330 can be connected to a load 360. The load 360 can be a DC load. The secondary converter 330 can be designed to output this output voltage to the load 360.

[0043] Alternatively, the secondary converter 330 can be designed to receive an input voltage from a power supply 250. The power supply 250 can be a DC power supply. The input voltage can be a DC voltage.

[0044] In various embodiments, the primary converter 310 can be designed to output an output voltage. This output voltage can be a DC voltage. The primary converter 310 can be connected to a load 360. The load 360 can be a DC load. The primary converter 310 can be designed to output this output voltage to the load 360.

[0045] In various embodiments, the primary converter 110 may have multiple switches. In some embodiments, the multiple switches may be field-effect transistors (FETs), such as metal-oxide-semiconductor field-effect transistors (MOSFETs). In some embodiments, the multiple switches may be insulated-gate bipolar transistors (IGBTs).

[0046] In various embodiments, the secondary converter 330 may have multiple switches. In some embodiments, the multiple switches may be field-effect transistors (FETs), such as metal-oxide-semiconductor field-effect transistors (MOSFETs). In some embodiments, the multiple switches may be insulated-gate bipolar transistors (IGBTs).

[0047] In various implementations, converter 300 may be a dual-active bridge converter. The primary converter may be or have a first active bridge circuit. The secondary converter may be or have a second active bridge circuit.

[0048] In various embodiments, the converter 300 may have a first pair of switches 371, 372 and a second pair of switches 376, 377. The first pair of switches 371, 372 and the second pair of switches 376, 377 may be connected in a first active bridge circuit.

[0049] In various embodiments, the first active bridge circuit may have a first half-bridge circuit 370 and a second half-bridge circuit 375.

[0050] In various implementations, the first half-bridge circuit 370 may have a first pair of switches 371, 372.

[0051] In various implementations, the second half-bridge circuit 375 may have a second pair of switches 376, 377.

[0052] In various embodiments, the converter 300 may have a third pair of switches 381, 382 and a fourth pair of switches 386, 387 among the plurality of switches. The third pair of switches 381, 382 and the fourth pair of switches 386, 387 may be connected in a second active bridge circuit.

[0053] In various implementations, the second active bridge circuit may have a third half-bridge circuit 380 and a fourth half-bridge circuit 385.

[0054] In various implementations, the third half-bridge circuit 380 may have a third pair of switches 381, 382.

[0055] In various implementations, the fourth half-bridge circuit 385 may have a fourth pair of switches 386, 387.

[0056] In various implementations, each switch in each of the first, second, third, and fourth pairs of switches operates in complementary operation with the other switch in that pair; that is, when one switch is on, the other switch is off. These switches can be controlled by control circuitry, such as a gate driver.

[0057] In various embodiments, one of the first pair of switches 371, 372 can be controlled by a first strobe signal. The first strobe signal can be a voltage signal. The on / off state of one of the first pair of switches 371, 372 can be controlled by this first strobe signal, which is sent to the control connection terminal of one of the first pair of switches 371, 372, such as the gate connection terminal of a MOSFET switch. The other switch in the first pair of switches 371, 372 can be controlled by a logic-inverted first strobe signal. For example, switch 371 can be turned on while switch 372 can be turned off, or switch 372 can be turned on while switch 371 can be turned off.

[0058] In various embodiments, one of the switches in the second pair of switches 376, 377 can be controlled by a second strobe signal. The second strobe signal can be a voltage signal. The on / off state of one of the switches in the second pair of switches 376, 377 can be controlled by this second strobe signal, which is sent to the control connection terminal of one of the switches in the first pair of switches 376, 377, such as the gate connection terminal of a MOSFET switch. The other switch in the second pair of switches 376, 377 can be controlled by a logic-inverted first strobe signal. For example, switch 376 can be turned on while switch 377 can be turned off, or switch 377 can be turned on while switch 376 can be turned off.

[0059] In various embodiments, one of the switches in the third pair 381, 382 can be controlled by a third strobe signal. The third strobe signal can be a voltage signal. The switching on and off of one of the switches in the third pair 381, 382 can be controlled by this third strobe signal, which is sent to the control connection terminal of one of the switches, such as the gate connection terminal of a MOSFET switch. The other switch in the third pair 381, 382 can be controlled by a logic-inverted first strobe signal. For example, switch 381 can be turned on while switch 382 can be turned off, or switch 382 can be turned on while switch 381 can be turned off.

[0060] In various embodiments, one of the fourth pair of switches 386, 387 can be controlled by a fourth strobe signal. The fourth strobe signal can be a voltage signal. The switching on and off of one of the fourth pair of switches 386, 387 can be controlled by this fourth strobe signal, which is sent to the control connection terminal of one of the fourth pair of switches 386, 387, such as the gate connection terminal of a MOSFET switch. The other switch in the fourth pair of switches 386, 387 can be controlled by a logic-inverted first strobe signal. For example, switch 386 can be turned on while switch 387 can be turned off, or switch 387 can be turned on while switch 386 can be turned off.

[0061] According to various implementations, at least one of the first gating signal, the second gating signal, the third gating signal, and the fourth gating signal (e.g., all gating signals) may exist in the form of a pulse wave, such as a rectangular wave.

[0062] In some implementations, the converter 300 may have a gate driver chip that can provide complementary signals with a dead time, which may be referred to as the blanking time. The blanking time can be the time interval between these complementary signals. This time interval can be from 10 ms to 20 ms. The blanking time can be between 0% and 20% of the switching period (Tsw). The blanking time can be related to the switching frequency (freq_sw).

[0063] Alternatively, these gating signals can be the same, but the MOSFET switches can be complementary. For example, one switch in each pair can be a p switch, while the other switch in each pair can be an n switch.

[0064] In various implementations, each of these strobe signals can be inverted and / or level-adapted as needed, for example, depending on the characteristics of the transistor that should be operated by the strobe signal.

[0065] In various embodiments, the control unit (not shown) of the converter 300 can be designed to control the first pair of switches 371, 372 and / or the second pair of switches 376, 377 and / or the third pair of switches 381, 382 and / or the fourth pair of switches 386, 387 in a manner that reduces switching losses. For example, the control unit can be designed to control all switches in the first pair of switches 371, 372, the second pair of switches 376, 377, the third pair of switches 381, 382, ​​and the fourth pair of switches 386, 387. This control unit can reduce the switching losses to zero, thereby achieving zero-voltage switching (ZVS).

[0066] In various implementations, the control unit can be designed to phase shift the first gating signal and the second gating signal by a first time interval. To achieve maximum current flowing through the primary side of the alternating power grid 320, the phase shift between the first and second gating signals can be 90 degrees. When, for example, switch 371 is turned on, switch 376 can be turned off. This can cause maximum current to flow to the primary side of the alternating power grid 320.

[0067] In various implementations, the control unit may also be designed to shift the third strobe signal and the fourth strobe signal by a second time interval.

[0068] In various implementations, the control unit may also be designed to shift the first strobe signal and the third strobe signal by a third time interval.

[0069] In various implementations, the control unit may also be designed to phase-shift the second strobe signal and the fourth strobe signal by a fourth time interval.

[0070] In various implementations, the duration of one or more of the first, second, and third time intervals can be related to the degree of phase shift. In various implementations, this phase shift can be within the range of 0 to 180 degrees. The phase between the two signals can be determined using the difference between the leading and trailing edges of the signals. The absolute time interval (e.g., in milliseconds) of one or more of the first, second, and third time intervals can be determined using a switching frequency (freq_sw). For example, the absolute time interval can be calculated as (phase shift / 360)*(1 / freq_sw).

[0071] The first phase shift (alpha) between the first strobe signal and the second strobe signal can range from 0 to 180 degrees, wherein when the first phase shift is 0 degrees, there can be zero voltage across the primary winding, and when the first phase shift is 180 degrees, there can be maximum voltage across the primary winding. When the first phase shift between the first strobe signal and the second strobe signal is 180 degrees, the first time interval can be 0.5*(l / freq_sw).

[0072] The second phase shift (beta) between the third and fourth strobe signals can range from 0 to 180 degrees. When the second phase shift is 0 degrees, there can be zero voltage across the secondary winding, and when the second phase shift is 180 degrees, there can be maximum voltage across the secondary winding. When the second phase shift between the third and fourth strobe signals is 180 degrees, the second time interval can be 0.5*(l / freq_sw).

[0073] The third phase shift (delta) between the first and third strobe signals can range from -90 to 90 degrees. When the third phase shift is -90 degrees, maximum power transfer in the negative direction is possible. When the third phase shift is 0 degrees, zero power transfer between the primary and secondary windings is possible. And when the third phase shift is 90 degrees, maximum power transfer in the positive direction is possible. When the third phase shift is 90 degrees, the third time interval can be 0.25*(l / freq_sw). In some embodiments, when the third phase shift is 0 degrees, if the primary winding voltage and the reflected secondary winding voltage (secondary * turns ratio) are not equal, minimum power transfer between the primary and secondary windings is possible. Current flow is possible, for example, when the primary winding voltage is 10 Vac and the reflected secondary winding voltage is 9 Vac. The current can be (10-9) / (impedance of the alternating grid (lmpedanz_des_Wechselstromnetzes)).

[0074] In various embodiments, the converter 300 may have a database. This database may be a lookup table. In various embodiments, the database may contain data that considers the input voltage, output voltage, and desired power of the converter 300. In some embodiments, the lookup table may be a three-dimensional table. In some embodiments, the lookup table may have three inputs. These three inputs may be the input voltage, the output voltage, and the desired power or the desired current. For example, the input voltage may be 350 V, the output voltage may be 30 V, and the desired current may be 20 A. In some embodiments, the lookup table may have three outputs. These three outputs may be a first phase shift, a second phase shift, and a third phase shift. The first phase shift may be a value between 0 and 180 degrees. The second phase shift may be a value between 0 and 180 degrees. The third phase shift may be a value between -90 and 90 degrees. In some embodiments, the first, second, and third phase shifts may be expressed in absolute time. In some embodiments, the database may have pre-calculated output values. In some embodiments, known input values ​​operating under ZVS conditions may be filled with corresponding output values. In some implementations, known input values ​​that are not operating under ZVS conditions can be filtered out, or these input values ​​can be set to zero for all three output values. For example, in the case of an overcurrent with an input voltage of 350 V, an output voltage of 30 V, and a desired current of 35 A (which exceeds the table limit of 5 A), the first phase shift, the second phase shift, and the third phase shift can be zero, which can cause the converter to stop transmitting power.

[0075] In various implementations, the database may be a lookup table. The lookup table may be an array of indexes. The lookup table may be arranged as key-value pairs, where the key is the data item being searched and the value is the data output of the lookup table. For example, the key may be the input and / or output parameters of the converter, and the data output of the lookup table may be at least one of the first to fourth phase shift time intervals.

[0076] In various implementations, the first time interval and / or the second time interval and / or the third time interval can be obtained from data in the database using input parameters or output parameters.

[0077] In various implementations, the determination of the first time interval and / or the second time interval and / or the third time interval when using this database may involve: taking into account the impedance of the alternating power grid 320.

[0078] In various implementations, the input parameter can be the input voltage. In various implementations, the input parameter can be the input current.

[0079] In various implementations, the output parameter can be the output voltage. In various implementations, the output parameter can be the output current.

[0080] In various implementations, when the input or output parameters exceed the values ​​of the data in the database, the first time interval and / or the second time interval and / or the third time interval can be set to zero. In various implementations, the first time interval and / or the second time interval and / or the third time interval can be set to zero during the switching period. When these time intervals are zero, the phase shift between the strobe signals is 0 degrees. When, for example, the first time interval is zero, the phase shift between the first strobe signal and the second strobe signal is zero. This results in no current flowing into the alternating current grid 320, which can protect the converter 300 during events such as undervoltage, overvoltage, and overcurrent.

[0081] In various embodiments, when the first phase shift is 0 degrees, although the switches are always turned on and off at the switching frequency, the voltage through the primary winding can be 0 V. In various embodiments, when the second phase shift is 0 degrees, although the switches are always turned on and off at the switching frequency, the voltage through the secondary winding can be 0 V. In some embodiments, when both the first and second phase shifts are 0 degrees, the current flowing through the converter, I = (0 Vac - 0 Vac) / alternating current impedance (Wechselstrom_Impedanz), is 0 A. In some embodiments, the third phase shift can be set to 0 degrees to prevent further power transmission.

[0082] In various embodiments, the description of converter 100 and / or converter 200 also applies to converter 300.

[0083] Figure 4 A diagram 400 illustrates a first gating signal 410 and a second gating signal 420 having a phase shift 430 according to various embodiments.

[0084] As shown in Figure 400, a pair of phase-shifted periodic gating signals 410 and 420 during the switching period Tsw is illustrated, where the horizontal axis 450 represents time and the vertical axis 460 represents voltage. The first gating signal 410 for the first switch and the second gating signal 420 for the second switch are phase-shifted by a time interval φ.

[0085] In various embodiments, the converter can be used in general power supply. In various embodiments, the converter can be used in or used in electric transportation devices, such as e-scooter chargers. In various embodiments, the converter can be used in vehicle-to-DC / DC converters. In various embodiments, the converter can be used in chargers for electric vehicles (EVs). In various embodiments, the DC / DC converter can be used in photovoltaic (PV) systems, such as in PV home energy storage systems. In various embodiments, the converter can be used in any suitable equipment using PSFB or DAB.

[0086] In various embodiments, the converter may have a protection system capable of reacting during switching periods. In various embodiments, the converter may have the advantage of having no control delay because no regulation loop is used. In various embodiments, a regulation loop may be present, but its use or significance may be irrelevant. For example, the regulation loop may be used to set the resistance or temperature dependence of some components. The database can handle 98-99% of the power transfer, while the remaining 1-2% can be handled by the regulation loop. Therefore, the control delay is negligible.

[0087] In various implementations, the converter may have the advantage that it can self-protect itself without any additional circuitry or with a reduced number of additional circuitry.

Claims

1. A converter designed to receive an input voltage and output an output voltage, wherein the converter comprises: Multiple switches; and A control unit is connected to the plurality of switches, wherein the control unit is designed to control the plurality of switches of the converter based on data in a database, using input parameters or output parameters, thereby enabling zero-voltage switching (ZVS). The converter includes: A primary converter, the primary converter being designed to receive the input voltage from a power source; An alternating current (AC) power grid, which is electrically coupled to the primary converter; A secondary converter, designed to output an output voltage, wherein the secondary converter is electrically coupled to the alternating current grid. The primary converter includes a first pair of switches and a second pair of switches, wherein the first pair of switches and the second pair of switches are connected in a first bridge circuit, and The secondary converter includes a third pair of switches and a fourth pair of switches, which are connected in a second bridge circuit. The first pair of switches is controlled by a first gating signal, the second pair of switches is controlled by a second gating signal, the third pair of switches is controlled by a third gating signal, and the fourth pair of switches is controlled by a fourth gating signal. The control unit is designed to: shift the first strobe signal and the second strobe signal by a first time interval; shift the third strobe signal and the fourth strobe signal by a second time interval; and shift the first strobe signal and the third strobe signal by a third time interval. The first time interval, the second time interval, and the third time interval are obtained from data in the database when using the input parameters or the output parameters. When the input parameter or the output parameter exceeds the value of the data in the database, the first time interval, the second time interval, and the third time interval are set to zero. The first time interval, the second time interval, and the third time interval are set to zero during the switching period. When the first time interval, the second time interval, and the third time interval are set to zero, the first pair of switches, the second pair of switches, the third pair of switches, and the fourth pair of switches are always turned on and off at the switching frequency.

2. The converter according to claim 1, The first bridge circuit includes a first half-bridge circuit and a second half-bridge circuit, wherein the first half-bridge circuit includes the first pair of switches and the second half-bridge circuit includes the second pair of switches; and The second bridge circuit includes a third half-bridge circuit and a fourth half-bridge circuit, wherein the third half-bridge circuit includes the third pair of switches and the fourth half-bridge circuit includes the fourth pair of switches.

3. The converter according to claim 1 or 2, wherein the control unit is configured to control the plurality of switches such that one switch in each of the first pair of switches, the second pair of switches, the third pair of switches, and the fourth pair of switches is turned on and one switch is turned off.

4. The converter according to claim 1 or 2, wherein the database is a lookup table, and wherein the input parameter and / or the output parameter is the input of the lookup table and the output of the lookup table is at least one of the first time interval, the second time interval, and the third time interval.

5. The converter according to claim 1 or 2, wherein the input parameter is the input voltage and the output parameter is the output voltage.

6. A method for operating a converter, comprising: When using control units connected to multiple switches of the converter, the multiple switches are controlled based on data in a database using input or output parameters, enabling zero-voltage switching (ZVS). The converter is designed to receive input voltage and output output voltage. The converter mentioned above includes: A primary converter, the primary converter being designed to receive the input voltage from a power source; An alternating current (AC) power grid, which is electrically coupled to the primary converter; A secondary converter, designed to output an output voltage, wherein the secondary converter is electrically coupled to the alternating current grid. The primary converter includes a first pair of switches and a second pair of switches, wherein the first pair of switches and the second pair of switches are connected in a first bridge circuit, and The secondary converter includes a third pair of switches and a fourth pair of switches, which are connected in a second bridge circuit. The first pair of switches is controlled by a first gating signal, the second pair of switches is controlled by a second gating signal, the third pair of switches is controlled by a third gating signal, and the fourth pair of switches is controlled by a fourth gating signal. The control unit is designed to: shift the first strobe signal and the second strobe signal by a first time interval; shift the third strobe signal and the fourth strobe signal by a second time interval; and shift the first strobe signal and the third strobe signal by a third time interval. The first time interval, the second time interval, and the third time interval are obtained from data in the database when using the input parameters or the output parameters. When the input parameter or the output parameter exceeds the value of the data in the database, the first time interval, the second time interval, and the third time interval are set to zero. The first time interval, the second time interval, and the third time interval are set to zero during the switching period. When the first time interval, the second time interval, and the third time interval are set to zero, the first pair of switches, the second pair of switches, the third pair of switches, and the fourth pair of switches are always turned on and off at the switching frequency.

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