Parallel boost converters having coupled inductors, and method for balancing detected actual current values

Abstract

The invention relates to a power converter (200) which can be operated in a converter mode in order to convert an electrical input power into an electrical output power, said power converter (200) comprising: a first channel (106) having a first inductor (110); a second channel (108) having a second inductor (112) which is coupled to the first inductor (110); and a control device (130); wherein the control device (130) can be operated outside the converter mode in accordance with a first algorithm (146) in order to determine a difference between the first channel (106) and the second channel (108); and wherein the control device (130) can be operated in the converter mode in accordance with a second algorithm (168) in order to change measured values from at least one measuring device on the basis of the determined difference. The invention also relates to a method for operating a power converter (200) and to a computer program product.

Description

[0001] PARALLEL BOOST CONVERTERS WITH COUPLED INDUCTIVORS AND METHOD FOR ADJUSTING THE ACTUAL CURRENT VALUE SENSING

[0002] Description

[0003] TECHNICAL FIELD

[0004] The present disclosure relates to the field of power converters.

[0005] BACKGROUND

[0006] An article by M. Soldano, X. Huang, G. Bernardinis, B. Miao, and N. Dhanjal, "A new current balancing method for digitally controlled interleaved PFC," 2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC), Orlando, FL, USA, 2012, pp. 299-303, doi: 10.1109 / APEC.2012.6165834, concerns a current balancing method for digitally controlled interleaved power factor correction (PFC). In the interleaved PFC topology, phase current asymmetry can lead to long-term reliability problems. In contrast to the conventional active current balancing method, a method is proposed that detects the sum of the switch currents, digitally decouples the difference in the switch currents, and compensates for the current difference by adjusting the duty cycle. The proposed method has two current measuring points.One is the sensed input current, the other is the sum of the switch current, which is sensed across a single current-sense resistor. A time-triggered SPDT switch is used to decouple the switching current.

[0007] SUMMARY

[0008] In view of the situation described above, there may be a need for a technique that allows to provide a power converter and a method for operating a power converter with improved characteristics.

[0009] This need can be addressed by the independent claims. Some advantageous embodiments are specified in the dependent claims.

[0010] According to a first aspect of the subject matter disclosed herein, a power converter is provided.

[0011] According to an embodiment of the first aspect, a power converter is provided which is operable in a converter mode for converting an electrical input power into an electrical output power, the power converter comprising: a first channel with a first inductor; a second channel with a second inductor coupled to the first inductor; and a control device; wherein the control device is operable without the converter mode according to a first algorithm to determine a difference between the first channel and the second channel; and wherein the control device is operable in a converter mode according to a second algorithm to change measured values ​​of at least one current measuring device based on the determined difference.

[0012] According to a second aspect of the subject matter disclosed herein, a method of operating a power converter is provided.

[0013] According to an embodiment of the second aspect, a method for operating a power converter is provided, wherein the power converter, in a converter mode, converts an electrical input power into an electrical output power, and wherein the power converter has a first channel with a first inductor and a second channel with a second inductor coupled to the first inductor, the method comprising: performing a first algorithm without the converter mode to determine a difference between the first channel and the second channel; performing a second algorithm during the converter mode to change measured values ​​of at least one measuring device based on the determined difference. According to a third aspect of the subject matter disclosed herein, a computer program product is provided.

[0014] According to an embodiment of the third aspect, a computer program product is provided, the computer program product comprising a program element which, when executed on a processor device, controls a method according to the second aspect.

[0015] DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0016] Although certain disadvantages of prior technologies are mentioned herein, the claimed subject matter is not intended to be limited to implementations that overcome some or all of the noted disadvantages of the prior technologies. Furthermore, although certain advantages of the subject matter disclosed herein are mentioned or implied in the present disclosure, the claimed subject matter is not intended to be limited to implementations that have some or all of those advantages.

[0017] In the following, exemplary embodiments of the subject matter disclosed herein are described, for example, with reference to a power converter and a method for operating a power converter and a computer program product. It should be emphasized that any combination of features of different aspects, embodiments, and examples is naturally possible. In particular, some embodiments are described with reference to a method, while other embodiments are described with reference to a device. Yet other embodiments are described with reference to a computer program product, while other embodiments are described with reference to a control device for interacting with elements of the power converter.However, those skilled in the art will appreciate from the above and following description, claims, and drawings that, unless otherwise stated, features of different aspects, embodiments, and examples may be combined, and such combinations of features are to be considered as disclosed by this application. For example, even a feature relating to a method may be combined with a feature relating to a device, and vice versa. According to one embodiment, a power converter according to the first aspect is operable in a converter mode for converting an electrical input power into an electrical output power, for example, for converting an electrical input voltage into an electrical output voltage.

[0018] According to one embodiment, the power converter has a first channel with a first inductor and a second channel with a second inductor, which according to a further embodiment is coupled to the first inductor. According to a further embodiment, the power converter has a control device. According to one embodiment, the control device is operable without the converter operation according to a first algorithm to determine a difference between the first channel and the second channel. According to a further embodiment, the control device is operable in the converter operation according to a second algorithm to change measured values ​​of at least one measuring device based on the determined difference.

[0019] According to one embodiment, the power converter of a method according to the second aspect is a power converter which, in a converter mode, converts an electrical input power into an electrical output power and which has a first channel with a first inductor and a second channel with a second inductor which, according to a further embodiment, is coupled to the first inductor.

[0020] According to one embodiment, the method comprises performing a first algorithm without converter operation to determine a difference between the first channel and the second channel. According to another embodiment, the method comprises performing a second algorithm during converter operation to change measured values ​​of at least one measuring device based on the determined difference.

[0021] According to one embodiment, a computer program product according to the third aspect comprises a program element. According to one embodiment, the program element is configured, when executed on a processor device, to control a method according to the second aspect. At least some of the aspects and embodiments of the subject matter disclosed herein are based on the idea that current balancing in a power converter with two or more channels is enabled in a simple and efficient manner by determining a difference between a first channel and a second channel in an operating state in which the power converter is not in converter operation, and changing (adjusting) measured values ​​of a measuring device based on the determined difference.

[0022] According to one embodiment, the power converter is configured as an interface between a power source (e.g., a power grid) and a load. Power converters can reduce or even eliminate harmonics in the power drawn from the power grid. This is also referred to as power factor correction (PFC).

[0023] According to one embodiment, the power converter comprises a first current measuring device for measuring a (first) electrical current through the first inductor and a second current measuring device for measuring a (second) electrical current through the second inductor. According to one embodiment, a current measuring device can be, for example, a resistive shunt. According to another embodiment, the current measuring device can be, for example, a Hall sensor or a magnetoresistive current sensor.

[0024] According to a further embodiment, the power converter comprises a first switch, by which the first current can be generated through the first inductor, and a second switch, by which the second current can be generated through the second inductor. The first and second switches can be, for example, a metal oxide field-effect transistor (MOSFET) or an insulated gate bipolar transistor (IGBT), or any other switching device suitable for switching at the required rate, for example in the range of 10 kHz to several hundred kHz (for example, 1 MHz).

[0025] According to one embodiment, the control device measures the currents through the first inductor and the second inductor during converter operation and controls the first switch and the second switch with pulses of a specific frequency and duration to carry out the power transfer. According to one embodiment, the at least one measuring device comprises the first current measuring device and the second current measuring device. According to one embodiment, a current balance is improved or established by changing the measured values ​​of the at least one measuring device. Consequently, according to one embodiment, the consequences of errors in the current measurement can be mitigated. Excessively large errors in the current measurement can cause premature saturation of the magnetic material of the inductors.While this could be reduced by increasing the size of the magnetic core, such an approach would result in a suboptimal design and increased resource consumption (e.g., amount of magnetic material, size, and weight).

[0026] Current balancing can prevent the elements of the two channels from being subjected to different current levels. This can avoid or at least reduce different electrical or thermal stress on the components of both channels. In the long term, this can increase the reliability of the circuit. Current balancing can be carried out, for example, using balancing factors. According to one embodiment, measured values ​​of at least one current sensor are changed by multiplying them by the balancing factor. For example, according to one embodiment, the balancing factor can be configured such that, for current balancing, only the second current measured by the second current measuring device (or the measured values ​​of the second current) is multiplied by the balancing factor.According to one embodiment, further changes, for example a change in measured values ​​of the first current, are not required for the current adjustment.

[0027] According to one embodiment, the control device is configured to use at least one of the first current measuring device, the second current measuring device, the first switch, and the second switch for both the first algorithm and the second algorithm. In other words, according to one embodiment, components required and provided for converter operation can also be used for implementing embodiments of the subject matter disclosed herein. This can simplify the circuit because, according to one embodiment, no additional components are required. Furthermore, manufacturing can be simplified because, according to one embodiment, no separate calibration or adjustment on the production line is required. Production time can also be shortened according to one embodiment.Furthermore, the construction of a circuit board on which the components of the power converter are arranged can be simplified because, according to one embodiment, no special connections for external measuring devices, such as current measuring devices, are required. Furthermore, according to one embodiment, flexibility can be increased. Since the implementation of embodiments of the subject matter disclosed herein uses the same circuitry that is also required for normal operation of the power converter, calibration or adjustment can be performed at any time, for example, during practical use. According to another embodiment, less accurate current measuring devices can be used (such as Hall sensors, which are required, for example, in the totem pole topology), which can have a sensitivity error of up to + / -3%.Furthermore, efficiency can be increased because embodiments of the subject matter disclosed herein allow for optimization of the magnetic core size. Without calibration, the size of the magnetic core would have to be increased to prevent premature saturation of the magnetic circuit, which could result from the low precision of the current measuring devices. Furthermore, according to one embodiment, drift of the current measuring devices can be compensated, for example, by periodically executing the first algorithm during practical use.

[0028] According to one embodiment, the first inductor and the second inductor are coupled, for example, via a common magnetic core. According to one embodiment, the coupled inductors represent different equivalent inductances, depending on their conduction mode and the applied voltages. The different equivalent inductances generate different rates of current change in the coils. These differences can be measured and used to determine the difference between the first channel and the second channel. It should be noted that embodiments of the subject matter disclosed herein symmetrize the current measurement, but do not necessarily increase the accuracy of the current measurement.

[0029] According to one embodiment, the difference between the first channel and the second channel includes or is based on at least one of the following: a difference between the first current measuring device and the second current measuring device; a difference between the first inductor and the second inductor; a difference between the sensitivity of the first current measuring device and the sensitivity of the second current measuring device. According to one embodiment, the difference is an absolute difference. According to another embodiment, the difference is a relative difference.

[0030] According to one embodiment, the first algorithm comprises a first mode and a second mode; wherein in the first mode, the first switch is electrically conductive and the second switch is electrically non-conductive; and wherein in the second mode, the first switch is electrically non-conductive and the second switch is electrically conductive.

[0031] The first / second mode is also referred to here as the first / second operating mode.

[0032] According to one embodiment, before the first mode is activated, both the first switch and the second switch are electrically non-conductive. Thus, upon activation of the first mode (starting with the non-conductive first switch and the non-conductive second switch), reproducible conditions prevail in the circuit, since both the first inductor and the second inductor are not energized.

[0033] According to one embodiment, the first switch and the second switch are electrically non-conductive prior to activation of the second mode. Thus, upon activation of the second mode (starting with the non-conductive first switch and the non-conductive second switch), a reproducible state can prevail in the circuit, since both the first inductor and the second inductor are not energized.

[0034] According to a further embodiment, activation of the first mode and / or the second mode only occurs when the current through the first inductor is zero and the current through the second inductor is zero.

[0035] According to one embodiment, the electrical input power is direct current power. According to one embodiment, the electrical input power is alternating current power. For example, according to one embodiment, an input of the power converter is connected to an alternating current network. According to a further embodiment, the first mode and / or the second mode is / are activated depending on a phase position of the electrical input power. For example, according to one embodiment, the first mode and / or the second mode is / are activated when a peak voltage of the electrical input power is present. By activating the first mode and / or the second mode depending on the phase position of the electrical input power, a reproducible state can prevail in the circuit.

[0036] According to one embodiment, the determination of the difference between the first channel and the second channel is improved by determining the difference in a reproducible state (e.g., in a predetermined state) of the power converter, for example, as described herein. For example, according to one embodiment, the first mode and the second mode can each be activated in a reproducible state (e.g., the predetermined state).

[0037] According to one embodiment, the electrical input power is an alternating current power; and the first mode is activated depending on a phase position of the electrical input power (in particular when a peak voltage of the electrical input power is present); and the second mode is activated temporally after the termination of the first mode, within the same half-period in which the first mode was activated. For example, the second mode is activated with a temporal offset from the first mode.

[0038] According to one embodiment, the first algorithm is executed twice consecutively to determine two adjustment factors depending on a direction of the currents through the first inductor and through the second inductor. For example, a first adjustment factor is determined for a first current direction of the first current and the second current, and a second adjustment factor is determined for a second current direction of the first current and the second current, wherein the second current direction is opposite to the first current direction in each case.

[0039] According to one embodiment, the difference is a relative difference between a sensitivity of the first current measuring device and a sensitivity of the second current measuring device. According to a further embodiment, the control device is configured to determine the following variables in the first algorithm at a first time and at a second time different from the first time: (i) a first voltage across the first inductor; (ii) a first current through the first inductor; (iii) a second voltage across the second inductor; and (iv) a second current through the second inductor.According to a further embodiment, the control device is configured to determine the relative difference between the sensitivity of the first current measuring device and the sensitivity of the second current measuring device from the first voltage, the second voltage, the first current and the second current at a first point in time and from the first voltage, the second voltage, the first current and the second current at a second point in time. For example, according to one embodiment, the control device is configured to operate in the first mode at the first point in time and to operate in the second mode at the second point in time. According to one embodiment, the first voltage, the second voltage, the first current and the second current are determined, on the one hand, upon activation of the first mode (i.e., at the first point in time) and, on the other hand, upon activation of the second mode (i.e., at the second point in time).

[0040] According to one embodiment, the power converter comprises a non-volatile memory, wherein the control device is configured to store the determined difference and / or a value derived therefrom in the non-volatile memory. For example, according to one embodiment, the relative difference between the sensitivity of the first current measuring device and the sensitivity of the second current measuring device is stored in the non-volatile memory.

[0041] According to one embodiment, the control device is configured to execute the first algorithm at a predetermined time. For example, the control device may be configured to execute the first algorithm once after the power converter is switched on. According to another embodiment, the control device may be configured to execute the first algorithm periodically, at predetermined time intervals. According to another embodiment, the control device may be configured to execute the first algorithm under predetermined operating conditions of the power converter.

[0042] According to one embodiment, the program element is a non-transient program element. According to another embodiment, the computer program product is a non-transient computer program product. As used herein, reference to a computer program product comprising a program element is considered equivalent to reference to a computer program comprising a program element and / or a computer-readable medium comprising a program element. According to one embodiment, the program element comprises instructions for controlling a processor device (having one or more microprocessors, e.g., a computer system) to effect and / or coordinate the execution of at least one method described herein.

[0043] The (non-transient) program element may be implemented as computer-readable instruction code using any suitable programming language, such as C, C++, assembly language, etc., and may be stored on a computer-readable medium (removable disk, volatile or non-volatile memory, embedded memory / processor, etc.). According to one embodiment, the instruction code is executable for programming a computer or any other programmable processor device to perform the intended functions. The computer program may be available on a network, such as the World Wide Web, from which it may be downloaded, for example.

[0044] The subject matter disclosed herein can be implemented by means of a computer program product (program element) or software. However, the subject matter disclosed herein can also be implemented by one or more specific electronic circuits or hardware. Furthermore, the subject matter disclosed herein can also be implemented in hybrid form, i.e., in a combination of software modules and hardware modules.

[0045] Unless otherwise stated, numerical values ​​are to be understood as including a ±5 Co window, ie, for example, a specification of 10 kHz according to one embodiment comprises a frequency within an interval of (10 ± 5%) kHz = [9.5 kHz; 10.5 kHz] and a percentage of 3% according to one embodiment comprises a percentage within an interval of 3% ± 5% = [2.85%; 3.15%]. According to a further embodiment, numerical values ​​are to be understood as including a ±10% window. According to one embodiment, a method disclosed herein can define the functionality of a device disclosed herein without being limited to the device-specific features (for example, a corresponding configuration of the control device).In this respect, any functionality of a device disclosed herein is intended to implicitly disclose a corresponding method defined exclusively by the disclosed functionality. Conversely, according to one embodiment, a method disclosed herein may be performed with any suitable known device (which may comprise a single element or multiple cooperating elements). In this respect, any method disclosed herein is intended to implicitly disclose a corresponding device configured to perform the method.

[0046] A general reference to embodiments (for example, of a power converter), for example by the formulation "according to at least one embodiment," by the formulation "according to one or more embodiments," or the formulation "according to embodiments," in particular also encompasses the feature combination of a corresponding independent claim without further restrictions (for example, the power converter according to claim 1). A reference to an aspect is further intended to encompass a reference to one or more embodiments. For example, a reference to a method according to the second aspect also encompasses a reference to a method according to one or more embodiments of the second aspect or of the method.

[0047] Unless expressly stated otherwise, a listing of features or process steps according to one embodiment does not yet define an order of the features or process steps in the order of the listing. According to another embodiment, a listing of features or process steps defines an order of the features or process steps as specified in the listing.

[0048] According to embodiments of the first aspect, the power converter is configured to provide the functionality of one or more of the embodiments disclosed herein and / or to provide the functionality required for one or more of the embodiments disclosed herein, in particular the embodiments of the first aspect, the second aspect, and / or the third aspect. According to embodiments of the second aspect, the method is configured to provide the functionality of one or more of the embodiments disclosed herein and / or to provide the functionality required for one or more of the embodiments disclosed herein, in particular the embodiments of the first aspect, the second aspect, and / or the third aspect.

[0049] According to embodiments of the third aspect, the computer program product is configured to provide the functionality of one or more of the embodiments disclosed herein and / or to provide the functionality required for one or more of the embodiments disclosed herein, in particular the embodiments of the first aspect, the second aspect and / or the third aspect.

[0050] Further advantages and features of the present disclosure will become apparent from the following exemplary description of currently preferred embodiments, to which the claimed invention is not limited, however. The individual figures of the drawings in this document are to be considered merely schematic and not to scale.

[0051] BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Fig. 1 shows a power converter according to embodiments of the subject matter disclosed herein.

[0053] Fig. 2 shows the gate voltage of the first switch and the currents through the first inductor and the second inductor for the first mode according to embodiments of the subject matter disclosed herein.

[0054] Fig. 3 shows a control device of the power converter of Fig. 1 according to embodiments of the subject matter disclosed herein, with associated measuring devices. Fig. 4 shows a first algorithm according to embodiments of the subject matter disclosed herein. According to one embodiment, the first algorithm 146 is executed without converter operation.

[0055] Fig. 5 shows a second algorithm according to embodiments of the subject matter disclosed herein.

[0056] Fig. 6 shows another power converter according to embodiments of the subject matter disclosed herein.

[0057] Fig. 7 shows another power converter according to embodiments of the subject matter disclosed herein.

[0058] DETAILED DESCRIPTION

[0059] It is noted that in different figures, similar or identical elements or components are provided with the same reference numerals, or with reference numerals that differ only in the first digit. Such features or components that are the same or at least functionally equivalent to the corresponding features or components in another figure are described in detail only at their first appearance in the following text, and the description is not repeated for subsequent appearances of these features and components (or the corresponding reference numerals).

[0060] It is understood that an exemplary implementation of the elements described below and provided with reference numerals is shown in the relevant drawings and is configured according to the following description, unless otherwise stated.

[0061] Fig. 1 shows a power converter 100 according to embodiments of the subject matter disclosed herein. According to one embodiment, the power converter is operable in a converter mode for converting an electrical input power (input voltage 101, also with u m), which is provided, for example, by a power grid 102, into an electrical output power with output voltage 104 (also denoted by Uo), as indicated in Fig. 1. According to one embodiment, the input voltage 101 is obtained by rectifying the mains voltage of the power grid 102, for example as shown in Fig. 1. The power converter 100 has, according to one embodiment, a first channel 106 and a second channel 108. The first channel 106 has, according to one embodiment, a first inductor 110 with an inductance L1 and the second channel 108 has a second inductor 112 with an inductance L2. According to one embodiment, the first inductor 110 and the second inductor 112 are coupled, for example as shown in Fig. 1.

[0062] According to one embodiment, the power converter 100 further comprises a first switch 114, by which a current i1 can be generated through the first inductor 110 (by closing the switch 114). Furthermore, according to one embodiment, the power converter 100 comprises a second switch 116, by which a current i2 can be generated through the second inductor 112 (by closing the switch 116). The voltage across the first inductor 110 is denoted by ul in Fig. 1, and the voltage across the second inductor 112 is denoted by u2. Each channel has a freewheeling diode 111, 113 in series with the corresponding inductor 110, 112, for example as shown in Fig. 1. According to one embodiment, the power converter 100 comprises a first current measuring device 136 for measuring the current i1 through the first inductor 110 and a second current measuring device 138 for measuring the current i2 through the second inductor 112.The current i1 through the first inductor 110 is also referred to herein as the first current and the current i2 through the second inductor 112 is also referred to herein as the second current.

[0063] Furthermore, the power converter has diodes 118 at its input.

[0064] If one of the switches 114, 116 is opened during converter operation, the associated inductor 110, 112 attempts to maintain current flow, and the voltage at the secondary end of the inductor rises until it exceeds the voltage across the charging capacitor 120 and opens the freewheeling diode 111, 113. According to one embodiment, a load 182 is connected to the charging capacitor 120, for example, as shown in Fig. 1.

[0065] In general, the behavior of the coupled inductors 110, 112 is described by the following system of differential equations: (1)

[0066] Here are

[0067] - u1 and u2 are the voltages across the inductors 110, 112, for example as shown in Fig. 1

[0068] - i1 and i2 are the currents through the respective inductor 110, 112 (inductor currents)

[0069] - L1 and L2 are the inductances of the inductors 110, 112

[0070] - M is the mutual inductance (mutual inductance)

[0071] The mutual inductance M is given by the following equation

[0072] (2)

[0073] M = k M ^L1L2

[0074] Here KM is the coupling factor of the inductances L1 , L2.

[0075] The system of differential equations (1) can be solved for the derivatives of the

[0076] Inductor currents:

[0077] (3)

[0078] Note that when the first inductor 110 is energized (i.e., current i1 increases), current i2 also increases due to the coupling of the two inductors 110, 112. According to the conduction state of the two switches 114, 116, the voltages u1 and u2 can be derived, so only the currents i1 and i2 are unknown.

[0079] According to one embodiment, the power converter is operable without converter operation according to a first algorithm to determine a difference between the first channel and the second channel. Furthermore, according to one embodiment, the first algorithm comprises a first mode and a second mode, wherein in the first mode the first switch 114 is electrically conductive and the second switch 116 is electrically non-conductive, and wherein in the second mode the first switch 114 is electrically non-conductive and the second switch 116 is electrically conductive. Consequently, in each mode only one switch is active (electrically conductive, i.e., in its conduction state). Consequently, according to one embodiment, the first mode and the second mode do not overlap in time, i.e., they are activated at different times.

[0080] According to one embodiment, the conduction state (i.e., the closed state) of switches 114, 116 is maintained briefly, on the order of several microseconds. For example, according to one embodiment, the conduction state of switches 114, 116 is activated for a period of time from 1 ps to 50 ps. The period of time during which the power state of a switch is activated is also referred to as the conduction time. Due to the short conduction time, the input voltage 101 and the output voltage 104 can be considered constant. This creates a linear current increase.

[0081] For the first mode, also referred to herein as mode A, the voltages u1 and u2 can be expressed as follows:

[0082] (4) where the superscript letter A denotes mode A.

[0083] By substituting (4) into (3) we obtain the variation of the inductor currents:

[0084] Analogously, for the second mode, which is also referred to here as mode B, we obtain:

[0085] (6)

[0086] (7)

[0087] The solutions given by equations (5) and (7) are valid if, according to one embodiment, the inductor currents are zero in the initial state. According to one embodiment, the initial time (time zero) for each operating mode is chosen to be the time at which the respective switch 114, 116 begins to conduct.

[0088] From solutions (5) and (7), it is further evident that the currents in the two inductors 110, 112 increase at different rates. For both modes (the first mode A and the second mode B), according to one embodiment, the evaluation of the currents and voltages is performed at the same time after activation of the corresponding switch to simplify the formal analysis and calculation. This time is referred to as Ts, and the currents are denoted as follows for simplicity: i = i (Ts)

[0089] Fig. 2 shows the gate voltage 122 of the first switch 114 and the current 123 (also denoted by i1) through the first inductor 110 and the current 125 (also denoted by i2) through the second inductor 112 for the first mode according to embodiments of the subject matter disclosed herein. Furthermore, the current values ​​at time Ts are indicated (see above). Note that the current i2 flows due to the coupling of the first inductor 110 and the second inductor 112 even though the second switch 116 is open (non-conducting) (see formula (3)).

[0090] As already explained above, according to one embodiment, the time at which the switch 114 is turned on (by a suitable gate voltage 122) is chosen as time zero, as shown in Fig. 2. As explained, the time period while the first mode is activated (in the interval [0; t1]) is, according to one embodiment, in an interval between 1 ps (1 microsecond) and 50 ps, ​​for example, between 1 ps and 15 ps. According to one embodiment, the time period t1 is chosen such that a measurable signal is obtained while avoiding high currents. As further explained, both the current i1 through the first inductor 110 and the current through the second inductor i2 are sampled (measured) at the same time Ts, according to one embodiment.According to another embodiment, the current i1 through the first inductor 110 and the current i2 through the second inductor 112 are sampled sequentially, as long as the time delay between the two current samples is much smaller than Ts to avoid introducing other errors. According to another embodiment, i1 and i2 can be sampled in two different half-periods of the input voltage 101.

[0091] The input voltage 101 and the output voltage 104 are determined according to a

[0092] In one embodiment, the voltages are sampled at the same time, Ts (the voltages are not shown in Fig. 2). Sequential sampling of the voltages is also possible. Typical analog-to-digital converters with a transfer rate of at least five megasamples per second (5 mega samples per second, 5 MSPS) may be suitable for this application, according to one embodiment.

[0093] According to one embodiment, the sampling of the currents and voltages for the second mode B is carried out analogously to the sampling of the currents and voltages for the first mode A described above.

[0094] As already explained above, the time of activation of the two operating modes (first mode A and second mode B) also plays an important role in one embodiment. According to one embodiment, the goal is to keep the conduction state very short in order to guarantee a linear current increase and avoid stress in the active elements. On the other hand, the duration of the conduction state must be long enough to obtain reliable values ​​for the measurements. According to one embodiment, it is therefore preferable to initiate the operating modes (i.e., the first mode A and the second mode B) synchronously with the peak value of the input voltage 101.

[0095] Using the measured values, the ratios of the currents in the first mode A and in the second mode B can be calculated for each channel:

[0096] (8)

[0097] Equation (8) can be solved as follows:

[0098] (9)

[0099] From equation (9) it can be seen that the ratio of the ß-factors provides the asymmetry of the magnetic circuit (more precisely the asymmetry of the inductors in their inductance):

[0100] (10)

[0101] Using equations (5) and (7), the factor y can be calculated as the ratio of the current in the first channel in mode A over the current in the second channel in mode B:

[0102] (11)

[0103] For converter operation of the power converter 100 in Fig. 1, the control device (not shown in Fig. 1) must measure voltages u1 and u2 and currents i1 and i2 and correctly process the results in order to adequately control the first switch 114 and the second switch 116.

[0104] Any current measuring device or any voltage measuring device will generate errors, such as sensitivity errors, offsets, or quantization errors. Voltage measuring devices (especially voltage sensors) can be manufactured very precisely, and thus, according to one embodiment, their errors can be ignored. In this case, the factor y in equation (11) is not affected by measurement errors.

[0105] However, current measurement devices, especially Hall sensors, can exhibit sensitivity errors of up to plus or minus 2% or more. Therefore, according to one embodiment, these errors are not neglected, as these errors may be unacceptable when coupled inductors are used in the power converter. Excessively large errors in current measurement can cause premature saturation of the magnetic material in the inductors. Although the size of the magnetic core can be increased, such an approach leads to a suboptimal design.

[0106] The following model is used for the current sensors:

[0107] (12) t = Sj£ i where:

[0108] - S / is the nominal sensor current sensitivity,

[0109] - ss is the sensitivity error,

[0110] - / the current at the sensor input is and

[0111] - i is the output of the current sensor (ie the input value supplied to the control device of the power converter).

[0112] Equation (12) ignores possible offset errors, as these can be eliminated using simple methods. Therefore, the focus below is on the sensitivity error.

[0113] Note that the ratios CM and «2 can be calculated from the measured inductor currents (Fj and FJ).

[0114] (13)

[0115] The same applies to ßi and ß2, as stated above. The ratio of the inductor currents in the first and second modes is then:

[0116] (14)

[0117] Equation (14) means that the relative sensitivity deviation of the two current measuring devices can be calculated by measuring corresponding voltages and currents (according to one embodiment, the first voltage u1 across the first inductor 110, the first current i1 through the first inductor 110, the second voltage u2 across the second inductor 112, and the second current i2 through the second inductor) at two different times in two different operating modes (according to one embodiment, the first mode A and the second mode B) of the power converter. The result of equation (14), E, ​​was obtained by executing a first algorithm according to embodiments of the subject matter disclosed herein during a period in which no converter operation occurred (i.e., the first algorithm was performed without converter operation).The parameter E can then be used in a transformer mode as a balancing factor for the current measurement, as described below.

[0118] (15)

[0119] In equation (15) and the current values ​​measured in the converter mode for the first inductor 110 and the second inductor 112, and i1sw and i2sw are the current values ​​for the first inductor 110 and the second inductor 112 used for operating the power converter 100 in the converter mode.

[0120] (16)

[0121] In equation (16), the measurement results for the current measurement in the first channel 106 and the second channel 108 are now affected by the same error and consequently the current measurement is adjusted according to one embodiment.

[0122] In summary, the power converter 100 described above or the method for operating the power converter 100 described above, according to one embodiment, comprises a first algorithm for calculating a balancing factor £, which is based on a difference between the first channel 106 and the second channel 108 of the power converter 100, and a second algorithm which, during converter operation of the power converter (i.e., during regular operation of the power converter), balances a current measurement in the first channel and in the second channel using the balancing factor e. In this way, according to one embodiment, current differences (in particular a maximum current load on the components) in the first channel and in the second channel can be compensated.

[0123] Fig. 3 shows a control device 130 of the power converter 100 of Fig. 1 according to embodiments of the subject matter disclosed herein with associated measuring devices.

[0124] According to one embodiment, the control device 130 comprises a processor device 132 and a memory 134, which may, for example, be a non-volatile memory. According to one embodiment, the memory is configured to store the difference between the first channel and the second channel, for example, the relative difference in the sensitivity of the current measuring devices of the first channel and the second channel (for example, the parameter e), determined according to a first algorithm of the subject matter disclosed herein. According to one embodiment, the control device 130 is signal-transmittingly connected to a first current measuring device 136 to receive the first current (flowing through the first inductor 110) measured by the first current measuring device 136.According to a further embodiment, the control device 130 is signal-transmittingly connected to a second current measuring device 138 to receive the second current (flowing through the second inductor 112) measured by the second current measuring device 138.

[0125] According to a further embodiment, the control device 130 is signal-transmittingly connected to a first voltage measuring device 140 in order to receive the first voltage u1 (dropped across the first inductor 110) measured by the first voltage measuring device 140. According to a further embodiment, the control device 130 is signal-transmittingly connected to a second voltage measuring device 142 in order to receive the second voltage u2 (dropped across the second inductor 112) measured by the second voltage measuring device 142.

[0126] A signal transmission connection, indicated at 144 in Fig. 3, may be, for example, an electrical connection, an optical connection, or a connection via an air interface, or any other connection suitable for implementing embodiments.

[0127] According to a further embodiment, the memory device has stored a program element of a computer program product according to embodiments of the subject matter disclosed herein. Accordingly, according to one embodiment, the program element is configured, when executed on the processor device 132, to control a method according to embodiments of the subject matter disclosed herein and / or to provide a functionality of the control device 130 as described with reference to embodiments of the power converter 100 or the method for operating the power converter 100.According to one embodiment, the control device 130 is configured to use the difference between the first channel and the second channel (e.g., the adjustment factor E) stored in the memory 134 during converter operation to change measured values ​​of at least one current measuring device based on the stored difference and thus perform a current adjustment between the first channel and the second channel. For example, according to one embodiment, the control device 130 is configured to use the adjustment factor E, i.e., the relative sensitivity deviation of the first current measuring device 136 and the second current measuring device 138, to multiply a measured value for the second current i2 by the adjustment factor E during converter operation and thereby adjust (balance) the current measurement between the first channel and the second channel.

[0128] According to one embodiment, the control device 130 is configured to determine the difference (e.g., the adjustment factor E) at one or more predetermined times, for example, upon initial commissioning or at periodic intervals.

[0129] According to a further embodiment, a control algorithm for the converter operation of the power converter 100 is stored in the memory device 134.

[0130] Figure 4 shows a first algorithm 146 according to embodiments of the subject matter disclosed herein. According to one embodiment, the first algorithm 146 is executed without converter operation.

[0131] According to one embodiment, initial conditions for the first algorithm 146 are first established, indicated at 148 in Fig. 4. Establishing the initial conditions 148 comprises, according to one embodiment, opening the first switch 114 and the second switch 116. Furthermore, establishing the initial conditions 148 comprises, according to one embodiment, waiting until the first current through the first inductor 110 and the second current through the second inductor 112 are zero. According to another embodiment, establishing the initial conditions 148 further comprises charging the capacitor to which the electrical output power is applied during converter operation.

[0132] According to a further embodiment, the first algorithm 146 comprises synchronization with the peak voltage of the electrical input power (for example, the peak voltage of a power grid), indicated at 150, which according to one embodiment is also available for implementing the first algorithm without converter operation. For this purpose, according to one embodiment, the system waits until an input voltage reaches its peak value. According to one embodiment, the polarity of the input voltage is irrelevant. According to another embodiment, the polarity of the input voltage is positive during synchronization. According to another embodiment, the polarity of the input voltage is negative during synchronization. According to another embodiment, the synchronization also comprises synchronization with the polarity of the input voltage.

[0133] According to a further embodiment, the first operating mode A is subsequently initiated, indicated at 152.

[0134] According to a further embodiment, data is subsequently recorded in the first operating mode A, indicated at 154. For this purpose, according to one embodiment, after the time period Ts has elapsed, the values ​​for the currents and

[0135] ' AA j A l i > l 2 > u m< u o ) are measured. According to one embodiment, the currents and voltages are sampled at the same time. According to another embodiment, the currents and voltages are sampled sequentially if the delay between samples does not introduce significant errors.

[0136] According to a further embodiment, the first operating mode A is subsequently terminated, indicated at 156 in Fig. 4.

[0137] According to a further embodiment, a second synchronization with the peak value of the input voltage (for example, the mains voltage), indicated at 158, then takes place. According to one embodiment, for this purpose, the system waits until the input voltage reaches its peak value again. According to a further embodiment, the polarity of the input voltage is irrelevant. According to a further embodiment, the polarity of the input voltage is positive during the second synchronization. According to a further embodiment, the polarity of the input voltage is negative during the second synchronization. According to a further embodiment, the second synchronization also includes synchronization with the polarity of the input voltage.

[0138] According to a further embodiment, the second synchronization at 158 ​​is omitted. Instead, the method waits until the current through the first inductor 110 and the current through the second inductor 112 are zero, indicated at 159. In this case, the first operating mode A and the second operating mode B are activated in the same half-period of the input voltage. The time until the current through the first inductor 110 and the current through the second inductor 112 have dropped to zero is, in one embodiment, between 100 ps (microseconds) and 500 ps, ​​for example, 300 ps. Compared to the duration of a half-period, such a time period is short enough to activate the second operating mode in the same half-period of the mains voltage and still keep the method profitable.

[0139] According to a further embodiment, the second operating mode B is subsequently initiated, indicated at 160.

[0140] According to a further embodiment, data is subsequently recorded in the second operating mode B, indicated at 162. For this purpose, according to one embodiment, after the time period Ts has elapsed, the values ​​for the currents and voltages measured. According to one embodiment, the currents and voltages are sampled at the same time. According to another embodiment, the currents and voltages are sampled sequentially if the delay between samples does not introduce significant errors.

[0141] According to a further embodiment, the second operating mode B is subsequently terminated, indicated at 164.

[0142] According to a further embodiment, the adjustment factor E is then calculated, indicated at 166. According to one embodiment, the following steps are carried out to calculate the adjustment factor: a) calculating a1 and a2 according to equation (13); b) calculating ß1 and ß2 according to equation (9); c) calculating y according to equation (11); d) calculating the adjustment factor E according to equation (14) e) storing the adjustment factor E for further use.

[0143] Figure 5 shows a second algorithm 168 according to embodiments of the subject matter disclosed herein. According to one embodiment, the second algorithm includes measuring the inductor currents of the power converter, indicated at 170.

[0144] According to another embodiment, the second algorithm comprises multiplying at least one of the inductor currents (e.g., the first inductor current and / or the second inductor current) by a trim factor. For example, according to one embodiment, the second algorithm comprises multiplying a measured value of the second inductor current by the trim factor E, indicated at 172.

[0145] Fig. 6 shows another power converter 200 according to embodiments of the subject matter disclosed herein. The operation of the coupled inductor, the formulas derived above, the first algorithm, and the second algorithm also apply unchanged to the power converter 200 according to one embodiment.

[0146] According to one embodiment, the power converter 200 is connected or connectable to the power grid 102.

[0147] According to one embodiment, the power converter 200 further includes a filter unit 174 having a filter 176 (e.g., an electromagnetic compatibility (EMC) filter) for attenuating interference caused by the various switches of the power converter 200.

[0148] According to another embodiment, power converter 200 includes a boost converter 178, whose task is to perform power factor correction (PFC). According to one embodiment, boost converter 178 has a totem pole topology, for example, as shown in Fig. 6.

[0149] The totem pole topology includes a first channel 106 and a second channel 108. The first channel 106 includes a first inductor 110, and the second channel includes a second inductor 112. According to one embodiment, the first inductor 110 and the second inductor 112 are coupled, for example, as shown in Fig. 6.

[0150] Compared to the boost converter of Fig. 1, in one embodiment of the totem pole topology, the current through the first inductor 110 and through the second inductor 112 will flow in both directions, depending on the polarity of the voltage of the power grid 102 (also referred to as the grid voltage). For example, during the negative half-cycle of the grid voltage, the currents through the first inductor 110 and through the second inductor 112 are negative; however, their magnitude is shown in an embodiment such as the first operating mode in Fig. 2.

[0151] According to one embodiment, the first channel 106 further comprises a first switch 114, 214, by which a current can be injected through the first inductor 110. In particular, in the totem pole topology, the first switch can be formed by different components depending on the polarity of the mains voltage, for example, either by switch 114 or switch 214, for example, as shown in Fig. 6. For example, if the mains voltage is positive, switch 214 forms the first switch according to embodiments of the subject matter disclosed herein. Switch 114 remains blocked, and its parallel diode acts as a freewheeling diode, for example, as shown in Fig. 6. If the mains voltage is negative, the roles change: Switch 114 forms the first switch, and switch 214 remains blocked, with its parallel diode acting as a freewheeling diode.

[0152] According to a further embodiment, the second channel 108 further comprises a second switch, by means of which a current can be impressed through the second inductor 112. In particular, in the totem pole topology, the second switch can be formed by different components depending on the polarity of the mains voltage, for example either by switch 116 or switch 216, for example as shown in Fig. 6. When the mains voltage is positive, switch 216 forms the second switch. Switch 116 remains blocked and its parallel diode acts as a freewheeling diode. When the mains voltage is negative, the roles reverse: Switch 116 forms the second switch and switch 216 remains blocked, with its parallel diode acting as a freewheeling diode.

[0153] According to one embodiment, current measuring devices 136, 138 in the form of current sensors are provided for measuring the inductor currents. According to one embodiment, the current sensors have a floating input, and their outputs are referenced to the ground of the control device 130. Furthermore, according to one embodiment, the boost converter 178 has a voltage measuring device in the form of a voltage sensor 180 for measuring the input voltage 101. According to one embodiment, the voltage sensor 180 can be implemented by a resistor network and an operational amplifier. For example, according to one embodiment, the voltage sensor 180 can be formed by a conventional differential amplifier structure. According to another embodiment, the voltage sensor V1 can be formed by a monolithic differential amplifier with optically isolated inputs.

[0154] According to one embodiment, the power converter 200 includes a DC link 181. According to one embodiment, the DC link includes a DC link capacitor 220. According to one embodiment, the DC link capacitor 220 acts as an energy storage device between the boost converter 178 and a load 182. According to one embodiment, the DC link capacitor is a battery of one or more electrolytic capacitors. According to one embodiment, the power converter 200 further includes a voltage sensor 183 for measuring the voltage across the DC link capacitor 220, for example, as shown in Fig. 6.

[0155] According to one embodiment, the load 182 uses the energy of the DC link for its operation.

[0156] According to one embodiment, the power converter 200 includes a gate driver 184 that conditions the pulse-width modulated signals that the gate driver 184 receives from the controller 130 to drive the gates of the power switches 114, 116, 117, 214, 216, 217 of the boost converter 178.

[0157] According to a further embodiment, the power converter 200 comprises a low-voltage supply 186, which generates suitable voltages for the gate driver 184 and the control device 130, for example, as shown in Fig. 6. According to a further embodiment, the power converter 200 comprises the control device 130, which, according to one embodiment, measures the inductor currents, the input voltage 101 (U_AC), and the DC link voltage U_DC and generates corresponding pulse-width modulated signals for operating the boost converter 178.The control device 130, which may also be referred to as a calculation unit, comprises, according to one embodiment, one or more of the following: a central processing unit 132 (for example, a microcontroller, a microprocessor, a digital signal processor (DSP)), which may include, for example, an arithmetic logic unit (ALU) and / or a floating point processing unit (FPU), a volatile memory 187 (for example, a random access memory (RAM)), a non-volatile memory 134, a suitable pulse width modulation timer 188 for generating the signals for the gate driver 184, an analog to digital converter (ADC) 189, and a communication interface 190 for communicating with an external device.

[0158] The elements of the control device 130 according to one embodiment may be separate hardware elements or may be all or partially integrated on a common semiconductor substrate. The connections between these elements (the bus system) are not shown for simplicity of illustration. The non-volatile memory 134 stores, according to one embodiment, at least the first algorithm 146, the second algorithm 168, and their parameters, for example, in the form of a computer program product according to embodiments of the subject matter disclosed herein. According to one embodiment, the volatile memory 187 stores intermediate results of the execution of the first algorithm and / or the second algorithm. According to one embodiment, the non-volatile memory 134 further stores a control algorithm for the operation of the power converter, for example, a control algorithm for the operation of the boost converter 178.

[0159] According to one embodiment, the first current measuring device 136 and / or the second current measuring device 138 have a sensitivity that depends on the current direction through the first inductor 110 and the second inductor 112. In this case, the sensitivity can be determined according to one embodiment by executing the first algorithm 146 twice to calculate a first adjustment factor for a first current direction and a second adjustment factor for a second current direction (which is different from the first current direction). According to one embodiment, the first synchronization occurs at 150 and the second synchronization occurs at 158, for example, with the positive peak value of the input voltage, for the first execution of the first algorithm 146.For the second execution of the first algorithm 146, for example, the first synchronization occurs at 150 and the second synchronization occurs at 158 ​​with the negative peak value of the input voltage. According to a further embodiment, the second synchronization at 158 ​​can be omitted and a wait at 159 can occur during the first execution of the first algorithm and the second execution of the first algorithm 146, for example, as symbolized by the dashed lines in Fig. 4.

[0160] According to one embodiment, the second algorithm 168 is extended accordingly, for example, such that the correction at 172 is performed depending on the current direction through the first inductor 110 and through the second inductor 112.

[0161] Fig. 7 shows another power converter 300 according to embodiments of the subject matter disclosed herein. The structure of power converter 300 is largely identical or at least analogous to power converter 200 from Fig. 6. For this reason, only differences will be discussed below.

[0162] According to one embodiment, the load 182 is formed by an inverter 191, which drives a motor 192, for example, as shown in Fig. 7. According to one embodiment, the control device comprises the necessary circuits for motor control, in particular a pulse width modulator timer 193 (PWM timer), a gate driver 194 for the motor 192, and an analog-to-digital converter 195 (ADC) for the motor 192. According to one embodiment, the number of inverter-motor pairs is not limited to one. Rather, there may be several inverters 191 connected in parallel to the DC link 181. In this case, the control device 130 is expanded by the necessary elements.

[0163] According to one embodiment, the control device 130 can be implemented by a single microcontroller or microprocessor for operating the boost converter 178 and the motors 192. According to another embodiment, the control device 130 can be implemented by splitting it into multiple microcontrollers or microprocessors, depending, for example, on the computing power, the degree of peripheral integration, and / or the memory capacity. In other words, according to one embodiment, the control device 130 comprises multiple microcontrollers or microprocessors.

[0164] While in some embodiments the power converter is configured to be connected to an AC power source (e.g., a power grid), according to another embodiment the power converter is configured to be connected to a DC power source. For example, according to one embodiment, the power converter may be a DC-DC converter. It is noted that embodiments of the subject matter disclosed herein may be applied to any type of power converter that includes a coupled inductor for implementing power transfer.

[0165] According to embodiments of the subject matter disclosed herein, any suitable entity (e.g., a component, a unit, or a device, e.g., the controller) may be provided at least partially in the form of corresponding computer programs that enable a processor device to provide the functionality of the corresponding entity as described herein. According to other embodiments, any suitable entity as described herein may be provided in hardware. According to other, hybrid embodiments, some entities may be provided in software while other entities are provided in hardware.

[0166] It should be noted that each entity disclosed herein (e.g., a component, a unit, or a device), such as a power converter or components thereof (e.g., a control device), is not limited to a dedicated entity as described in some embodiments. Rather, the subject matter described herein may be provided in various ways with varying granularity at the device level or at the software module level while still providing the specified functionality. Further, it should be noted that, according to embodiments, a separate entity (e.g., a software module, a hardware module, or a hybrid module) may be provided for each of the functions disclosed herein. According to other embodiments, an entity (e.g.,A single entity (e.g., a software module, a hardware module, or a hybrid module) may be configured to provide two or more functions as described herein. According to yet other embodiments, two or more entities (e.g., components, units, and devices) may be configured to jointly provide a function as described herein.

[0167] According to one embodiment, the control device includes a processor device having at least one processor for executing at least one program element, which may correspond to a corresponding software module.

[0168] It should be noted that the embodiments described herein represent only a limited selection of possible embodiments of the present disclosure. It is thus possible to combine the features of various embodiments in a suitable manner, so that a person skilled in the art will consider the embodiments explicitly disclosed here to be a plurality of combinations of various embodiments. Furthermore, it should be noted that terms such as "a" or "an" do not exclude a plurality. Terms such as "containing" or "having" do not exclude further features or method steps. Consequently, according to one embodiment, the term "having," "comprising," or "containing" means "among other things." According to another embodiment, the term "having," "comprising," or "containing" means "consisting of."According to one embodiment, the term “configured for” includes, among other things, the meaning “configured to”.

[0169] The term “in particular” refers herein to optional features in general.

[0170] The expression “A and / or B” usually always includes “only A”, “only B” and also “A and B”. In an expression that refers to a list of characteristics, “at least one” always includes the individual characteristics as well as any combination of the characteristics. For example, the expression “at least one of the characteristics A and B” includes the characteristic “only A”, “only B”, and “A and B”. Analogously, the expression “at least one of the characteristics A or B” also includes the characteristic “only A”, “only B”, and “A and B”. Analogously, the expression “at least one of the characteristics A, B” also includes the characteristic “only A”, “only B”, and “A and B”.

[0171] It should also be noted that reference numerals in the claims should not be construed as limiting the scope of the claims. Furthermore, it should be noted that reference numerals in the description and the description's reference to the drawings should not be construed as limiting the scope of the description. Rather, the drawings illustrate only one exemplary implementation of a particular combination of several embodiments of the subject matter disclosed herein; any other combination of embodiments is equally possible and is to be considered disclosed in this application.

[0172] In summary, it can be stated:

[0173] Described is a power converter operable in converter mode to convert an electrical input power into an electrical output power, the power converter comprising: a first channel with a first inductor; a second channel with a second inductor coupled to the first inductor; and a control device; wherein the control device is operable without converter mode according to a first algorithm to determine a difference between the first channel and the second channel; and wherein the control device is operable in converter mode according to a second algorithm to change measured values ​​of at least one measuring device based on the determined difference. Furthermore, a method for operating a power converter and a computer program product are disclosed.

[0174] REFERENCE NUMBER LIST

[0175] 100 power converters

[0176] 101 Input voltage

[0177] 102 Power grid

[0178] 104 Output voltage

[0179] 106 first channel

[0180] 108 second channel

[0181] 110 first inductor

[0182] 111 Freewheeling diode

[0183] 112 second inductor

[0184] 113 Freewheeling diode

[0185] 114 first switch

[0186] 116 second switch

[0187] 117 circuit breakers

[0188] 118 diodes

[0189] 120 charging capacitor

[0190] 122 Gate voltage

[0191] 123 Current through the first inductor

[0192] 125 Current through the second inductor

[0193] 130 Control device

[0194] 132 Processor device

[0195] 134 memory

[0196] 136 first current measuring device

[0197] 138 second current measuring device

[0198] 140 first voltage measuring device

[0199] 142 second voltage measuring device

[0200] 144 signal transmission connection

[0201] 146 first algorithm

[0202] 148 establishing initial conditions

[0203] 150 synchronization

[0204] 152 Start Mode A

[0205] 154 Data acquisition 156 End mode A

[0206] 158 Synchronization

[0207] 160 Start Mode B

[0208] 162 Data recording

[0209] 164 End Mode B

[0210] 166 Compensation factor

[0211] 168 second algorithm

[0212] 170 Measuring inductor currents

[0213] 172 Current measurement adjustment

[0214] 174 filter unit

[0215] 176 EMC filters

[0216] 178 boost converters

[0217] 180 voltage sensor

[0218] 181 DC link

[0219] 182 load

[0220] 183 Voltage sensor

[0221] 184 drivers

[0222] 187 non-volatile memory

[0223] 188 Pulse Width Modulation Timer

[0224] 189 analog-to-digital converters

[0225] 190 Communication interface

[0226] 191 inverters

[0227] 192 engine

[0228] 193 Pulse width modulation timer

[0229] 194 Driver for Motor

[0230] 195 analog-to-digital converters

[0231] 200 power converters

[0232] 214 circuit breakers

[0233] 216 circuit breakers

[0234] 217 circuit breakers

[0235] 220 DC link capacitor

[0236] 300 power converters

Claims

AMENDED CLAIMS received by the International Bureau on 22 November 2024 (22.11.2024) Claims

1. A power converter (100, 200, 300) operable in a converter mode to convert an electrical input power into an electrical output power, the power converter (100, 200, 300) comprising: a first channel (106) with a first inductor (110); a second channel (108) with a second inductor (112) coupled to the first inductor (110); a first current measuring device (136) for measuring a first electrical current through the first inductor (110); a second current measuring device (138) for measuring a second electrical current through the second inductor (112); and a control device (130); wherein the control device (130) is operable without the converter operation according to a first algorithm (146) to determine a difference between the first channel (106) and the second channel (108);and wherein the control device (130) is operable in the converter mode according to a second algorithm (168) to change measured values ​​of at least one measuring device based on the determined difference; wherein the at least one measuring device comprises the first current measuring device (136) and / or the second current measuring device (138).

2. Power converter (100, 200, 300) according to claim 1, further comprising: a first switch (114; 114, 214) by which the first current through the first inductor (110) can be generated; a second switch (116; 116, 216) by which the second current through the second inductor (112) can be generated; in particular, wherein the control device (130) is configured to control at least one of the first current measuring device (136), the second current measuring device (138), the first switch (114; 114, 214), and the second switch (116; 116, 216) AMENDED SHEET (ARTICLE 19) to be used for both the first algorithm (146) and the second algorithm (168).

3. The power converter (100, 200, 300) of claim 2, wherein the difference between the first channel (106) and the second channel (108) comprises and / or is based on at least one of the following: a difference between the first current measuring device (136) and the second current measuring device (138); a difference between the first inductor (110) and the second inductor (112); a difference between the sensitivity of the first current measuring device (136) and the sensitivity of the second current measuring device (138).

4. The power converter (100, 200, 300) of any of claims 2 or 3, wherein the first algorithm (136) comprises a first mode and a second mode; wherein in the first mode, the first switch (114; 114, 214) is electrically conductive and the second switch (116; 116, 216) is electrically non-conductive; and wherein in the second mode, the first switch (114; 114, 214) is electrically non-conductive and the second switch (116; 116, 216) is electrically conductive.

5. The power converter (100, 200, 300) of claim 4, wherein prior to activation of the first mode, the first switch (114; 114, 214) and the second switch (116; 116, 216) are electrically non-conductive; and prior to activation of the second mode, the first switch (114; 114, 214) and the second switch (116; 116, 216) are electrically non-conductive.

6. Power converter (100, 200, 300) according to any one of the Claims 4 or 5, wherein the electrical input power is an alternating current power and wherein the first mode and / or the second mode is activated depending on a phase position of the electrical input power, in particular wherein the first mode and / or the second mode is activated when a peak voltage of the electrical input power is present. AMENDED SHEET (ARTICLE 19)

7. Power converter (100, 200, 300) according to any one of claims 4 or 5, wherein the electrical input power is an alternating current power; and the first mode is activated depending on a phase position of the electrical input power, in particular wherein the first mode is activated when a peak voltage of the electrical input power is present; and the second mode is activated after the termination of the first mode, within the same half-period in which the first mode was activated, in particular wherein the second mode is activated at a time interval from the first mode.

8. The power converter (200, 300) of any one of claims 2 to 7, wherein the first algorithm (146) is executed twice in succession to determine two trim factors depending on a direction of the currents through the first inductor (110) and through the second inductor (112).

9. Power converter (100, 200, 300) according to any one of claims 1 to 8, wherein the difference is a relative difference between a sensitivity of the first current measuring device and a sensitivity of the second current measuring device; wherein the control device (130) is configured to determine the following quantities in the first algorithm (146) at a first time and at a second time different from the first time: (i) a first voltage across the first inductor (110); (ii) a first current through the first inductor (110); (iii) a second voltage across the second inductor (112); and (iv) a second current through the second inductor (112); wherein the control device (130) is configured to determine the relative difference between the sensitivity of the first current measuring device and the sensitivity of the second current measuring device from the first voltage, the second voltage, the first current, and the second current at the first time and the first voltage, the second voltage, the first current, and the second current at the second time.

10. Power converter (100, 200, 300) according to any one of claims 1 to 9, further comprising at least one of the following AMENDED SHEET (ARTICLE 19) a non-volatile memory, wherein the control device (130) is configured to store the determined difference and / or a quantity derived therefrom in the non-volatile memory; the control device (130) is configured to execute the first algorithm (146) at a predetermined time.

11. A method for operating a power converter (100, 200, 300), wherein the power converter (100, 200, 300) converts an electrical input power into an electrical output power in a converter mode, and wherein the power converter (100, 200, 300) has a first channel (106) with a first inductor (110) and a second channel (108) with a second inductor (112) coupled to the first inductor (110), a first current measuring device (136) for measuring a first electrical current through the first inductor (110), and a second current measuring device (138) for measuring a second electrical current through the second inductor (112), the method comprising: performing a first algorithm (146) without the converter operation to determine a difference between the first channel (106) and the second channel (108); Performing a second algorithm (168) during converter operation to change measured values ​​of at least one measuring device based on the determined difference, wherein the at least one measuring device comprises the first current measuring device (136) and / or the second current measuring device (138).

12. A computer program product comprising a program element configured to, when executed on a processor device (132), control a method according to claim 11. AMENDED SHEET (ARTICLE 19)

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