Switching module for a power electronic switching assembly

Abstract

Switch module for a power electronic switching assembly. A switch module (1) is described. The switch module (1) comprises an H-bridge circuit (2) with four switching assemblies and an active clamp circuit (6) with four controllable semiconductor switches (S5, S6,..., S8). Each switching assembly comprises a pair of controllable semiconductor switches (S1, S2,..., S4 and S9, S10,..., S12) electrically connected in anti-serial. Each switching assembly alternatively can comprise a controllable semiconductor switch and a diode electrically connected in series. The H-bridge circuit (2) comprises first and second AC bridge terminals (AC1, AC2) electrically connectable to a respective coil (4) and first and second DC bridge terminals (DC1, DC2) electrically connectable to a DC current source or to DC bridge terminals of another switch module. The active clamp circuit (6) comprises first and second DC clamp terminals (DC3, DC4) between which a energy storage device (C) is electrically connected. A plurality of switch modules can be electrically connected together to provide a power electronic switching assembly.

Description

Technical Field

[0001] This invention relates to a switching module for power electronic switching assemblies.

[0002] Power electronic switching assemblies may include multiple switching modules.

[0003] Power electronic switching assemblies can be part of a direct current (DC) motor, which includes a stator with multiple stator coils, each stator coil being electrically connected to a corresponding switching module. Power electronic switching assemblies can also be part of a power converter, wherein each switching module is electrically connected to a corresponding coil of a transformer assembly. Background Technology

[0004] EP23155859 describes a switching module that can be used to provide active commutation and energy recovery processes. In one arrangement, for example, a power electronic switching assembly includes multiple switching modules and can be used to provide energy-efficient commutation for a direct current (DC) motor.

[0005] refer to Figure 1 Each switch module 100 includes an H-bridge circuit 102, which includes: - The first and second AC bridge terminals AC1 and AC2 can be electrically connected to the corresponding coils 104 (e.g., the stator coils of a DC motor). - The first and second DC bridge terminals DC1 and DC2 can be electrically connected to a DC current source. - The first switch S1 is electrically connected between the first AC bridge terminal AC1 and the first DC bridge terminal DC1. - The second switch S2 is electrically connected between the first AC bridge terminal AC1 and the second DC bridge terminal DC2. - The third switch S3 is electrically connected between the second AC bridge terminal AC2 and the first DC bridge terminal DC1, and - The fourth switch S4 is electrically connected between the second AC bridge terminal AC2 and the second DC bridge terminal DC2.

[0006] Each switch module 100 also includes an active clamping circuit 106. The active clamping circuit 106 of each switch module 100 includes: - The first AC clamp terminal AC3 is electrically connected to the first AC bridge terminal AC1. - The second AC clamp terminal AC4 is electrically connected to the second AC bridge terminal AC2. - First and second DC clamping terminals DC3 and DC4, - The fifth switch S5 is electrically connected between the first AC clamp terminal AC3 and the first DC clamp terminal DC3. - The sixth switch S6 is electrically connected between the first AC clamp terminal AC3 and the second DC clamp terminal DC4. - The seventh switch S7 is electrically connected between the second AC clamp terminal AC4 and the first DC clamp terminal DC3. - The eighth switch S8 is electrically connected between the second AC clamp terminal AC4 and the second DC clamp terminal DC4, and - An energy storage device (e.g., capacitor C) is electrically connected between the first and second DC clamping terminals DC3 and DC4.

[0007] In each H-bridge circuit 102, first and second switches S1 and S2 are connected in series between first and second DC bridge terminals DC1 and DC2, forming a first bridge arm. Third and fourth switches S3 and S4 are connected in series between first and second DC bridge terminals DC1 and DC2, forming a second bridge arm. The DC terminals of the first and second bridge arms are connected in parallel. The node (or connection point) between the first and second switches S1 and S2 defines a first AC bridge terminal AC1, and the node between the third and fourth switches S3 and S4 defines a second AC bridge terminal AC2.

[0008] In each active clamping circuit, the fifth and sixth switches S5 and S6 are connected in series between the first and second DC clamping terminals DC3 and DC4, forming the first clamping arm. The seventh and eighth switches S7 and S8 are connected in series between the first and second DC clamping terminals DC3 and DC4, forming the second clamping arm. The first and second clamping arms are connected in parallel. The junction between the fifth and sixth switches S5 and S6 defines the first AC clamping terminal AC3, and the junction between the seventh and eighth switches S7 and S8 defines the second AC clamping terminal AC4. An energy storage device (i.e., capacitor C) is connected in parallel with the first and second clamping arms between the first and second DC clamping terminals DC3 and DC4.

[0009] Each switch S1, S2, ..., S8 in the H-bridge circuit 102 and the active clamping circuit 106 may include one or more controllable semiconductor switches. Any suitable controllable semiconductor switch or combination of switches can be used, such as a metal-oxide-semiconductor field-effect transistor (MOSFET), a vertical junction field-effect transistor (VJFET), an insulated-gate bipolar transistor (IGBT), and a gate-commutated thyristor. Separate diodes may optionally be connected in anti-parallel to each semiconductor switch, or the anti-parallel diodes may be an inherent feature of the semiconductor switch itself, such as the body diode of a MOSFET structure. Typically, each controllable semiconductor switch is turned on and off by a gating drive signal generated by a gating driver.

[0010] In the H-bridge circuit 102, each switch S1, S2, ..., S4 can be a bidirectional switch, that is, each switch can provide bidirectional voltage blocking capability for gating control using unidirectional current. Each bidirectional switch may include: (a) such as Figure 1 The diagram shows a pair of controllable semiconductor switches, or (b) a controllable semiconductor switch and a diode, wherein the pair of semiconductor devices are anti-series (or back-to-back) electrically connected—that is, one of the semiconductor devices blocks voltage in a first direction, while the other blocks voltage in a second direction opposite to the first direction. (As used herein, the term "semiconductor device" may refer to either a semiconductor switch or a diode where appropriate.) When current is flowing through one of the semiconductor switches in a particular direction, it can flow through the anti-parallel diode of the other semiconductor switch, which is anti-series connected. For example, in the case where each semiconductor switch is a MOSFET, the body diode will inherently act as an anti-parallel diode, such as... Figure 1 As shown in the image.

[0011] exist Figure 1 In one practical arrangement of the switch module 100 shown, each switch S1, S2, ..., S4 of the H-bridge circuit 102 is implemented as a pair of MOSFETs with anti-series electrical connection (i.e., arranged to conduct in opposite directions), and each switch S5, S6, ..., S8 of the active clamp circuit 106 is implemented as an IGBT with anti-parallel diodes D5a, D6a, ..., D8a. However, unlike conventional “off-the-shelf” pre-packaged modules in which controllable semiconductor switches are electrically connected to conduct in the same direction, this requires custom pre-packaged modules for the H-bridge circuit. In particular, each pre-packaged module includes a pair of MOSFETs with anti-series electrical connection in a common-source arrangement. Such custom pre-packaged modules are typically more expensive than conventional pre-packaged modules and may be available from a limited number of suppliers. As used herein, the term “pre-packaged module” refers to a power module in which semiconductor devices and optional other electronic components (e.g., temperature sensors) are packaged together in a suitable housing. These modules may also have pre-coated thermal interface materials, for example, to dissipate heat generated by the semiconductor devices. These pre-packaged modules are commonly used in wind and solar power generation, energy storage, power transmission and distribution, and traction applications.

[0012] While it is possible to implement the H-bridge circuit 102 using a single or discrete controllable semiconductor switch instead of a custom pre-packaged module, the rated voltage and current of such a single switch are typically either too low or too high to be achieved in a practical switching module, which may require a rated current, for example, in the range of approximately 200 to 500 A. On the other hand, many conventional pre-packaged modules use controllable semiconductor switches that require rated voltages and currents, for example, 1200 to 1700 V and 200 to 500 A. Such “off-the-shelf” or conventional pre-packaged modules offer the following advantages: - Lower cost - Available from a wide range of suppliers. - Using standardized construction, and - A variety of switching options (e.g., SiC MOSFETs and SiIGBTs) with the required rated voltage and current are available.

[0013] Conventional pre-packaged modules (e.g., chopper modules) with controllable semiconductor switches and diodes having anti-series electrical connections are also available. Summary of the Invention

[0014] This invention aims to address the problems identified above and provides an improved switching module that can be implemented in practice using "off-the-shelf" or conventional pre-packaged modules to take advantage of the cost and availability benefits mentioned above. This invention provides a switching module comprising: The H-bridge circuit includes: The first and second AC bridge terminals can be electrically connected to the corresponding coils. The first and second DC bridge terminals can be electrically connected to a DC current source or the DC bridge terminals of another switching module. The first switching assembly is electrically connected between the first AC bridge terminal and the first DC bridge terminal. The first switching assembly includes a first controllable semiconductor switch and a first semiconductor device (i.e., a controllable semiconductor switch or diode) connected in series. The second switching assembly is electrically connected between the first AC bridge terminal and the second DC bridge terminal. The second switching assembly includes a second controllable semiconductor switch and a second semiconductor device (i.e., a controllable semiconductor switch or a diode) connected in series. A third switching assembly, electrically connected between the second AC bridge terminals and the first DC bridge terminals, includes a third controllable semiconductor switch and a third semiconductor device (i.e., a controllable semiconductor switch or diode) connected in series. A fourth switching assembly, electrically connected between the terminals of the second AC bridge and the second DC bridge, includes a fourth controllable semiconductor switch and a fourth semiconductor device (i.e., a controllable semiconductor switch or diode) connected in series; and An active clamping circuit, the active clamping circuit comprising: First and second DC clamping terminals, The fifth controllable semiconductor switch is electrically connected between the first DC clamp terminal and the junction (or connection point) between the first controllable semiconductor switch and the first semiconductor device. The sixth controllable semiconductor switch is electrically connected between the second DC clamp terminal and the junction between the second controllable semiconductor switch and the second semiconductor device. The seventh controllable semiconductor switch is electrically connected between the first DC clamp terminal and the junction between the third controllable semiconductor switch and the third semiconductor device. The eighth controllable semiconductor switch is electrically connected between the second DC clamp terminal and the junction between the fourth controllable semiconductor switch and the fourth semiconductor device. The energy storage device is electrically connected between the first and second DC clamping terminals.

[0015] The junction between the first and second controllable semiconductor switches defines a first AC bridge terminal, and the junction between the third and fourth controllable semiconductor switches defines a second AC bridge terminal.

[0016] The switching components of an H-bridge circuit include a pair of controllable semiconductor switches connected in series: In one arrangement, the first, second, third, and fourth semiconductor devices are controllable semiconductor switches—that is, each switching component of the H-bridge circuit may include a pair of controllable semiconductor switches. The pair of controllable semiconductor switches of each switching component are anti-series electrically connected (i.e., arranged to conduct in opposite directions).

[0017] In this arrangement, for convenience, the first semiconductor device is referred to as the ninth controllable semiconductor switch, the second semiconductor device as the tenth controllable semiconductor switch, the third semiconductor device as the eleventh controllable semiconductor switch, and the fourth semiconductor device as the twelfth controllable semiconductor switch.

[0018] The first and ninth controllable semiconductor switches can be connected in anti-series. The first controllable semiconductor switch can be electrically connected to the first AC bridge terminal, and the ninth controllable semiconductor switch can be electrically connected to the first DC bridge terminal.

[0019] The second and tenth controllable semiconductor switches can be connected in anti-series. The second controllable semiconductor switch can be electrically connected to the first AC bridge terminal, and the tenth controllable semiconductor switch can be electrically connected to the second DC bridge terminal.

[0020] The third and eleventh controllable semiconductor switches can be connected in anti-series. The third controllable semiconductor switch can be electrically connected to the second AC bridge terminal, and the eleventh controllable semiconductor switch can be electrically connected to the first DC bridge terminal.

[0021] The fourth and twelfth controllable semiconductor switches can be connected in anti-series. The fourth controllable semiconductor switch can be electrically connected to the second AC bridge terminal, and the twelfth controllable semiconductor switch can be electrically connected to the second DC bridge terminal.

[0022] All controllable semiconductor switches in the switching module can be of the same type. In particular, it will be understood that controllable semiconductor switches of the same type can be used to implement both H-bridge circuits and active clamping circuits. All controllable semiconductor switches can have the same ratings.

[0023] For example, any suitable fully controllable semiconductor switch can be used, such as a metal-oxide-semiconductor field-effect transistor (MOSFET), a vertical junction field-effect transistor (VJFET), an insulated-gate bipolar transistor (IGBT), a high electron mobility transistor (HEMT), a bipolar junction transistor (BJT), and a gate-commutated thyristor (GCT) or a gate-turn-off thyristor (GTO). Separate diodes can optionally be connected in antiparallel to each semiconductor switch, or the antiparallel diodes can be an inherent feature of the semiconductor switch itself, such as the body diode of a MOSFET structure.

[0024] Typically, each controllable semiconductor switch is turned on and off by a gating drive signal generated by a gating driver.

[0025] In a particular arrangement, all controllable semiconductor switches of the H-bridge circuit and the active clamp circuit can be implemented as MOSFETs. The first and ninth controllable semiconductor switches are preferably connected in anti-series in a common-drain configuration. The second and tenth controllable semiconductor switches are preferably connected in anti-series in a common-source configuration. The third and eleventh controllable semiconductor switches are preferably connected in anti-series in a common-drain configuration. The fourth and twelfth controllable semiconductor switches are preferably connected in anti-series in a common-source configuration.

[0026] In one arrangement of the switching module, the first and second controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the first and second controllable semiconductor switches are arranged to conduct in the same direction. In other words, the first and second controllable semiconductor switches can be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0027] The third and fourth controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the third and fourth controllable semiconductor switches are arranged to conduct in the same direction. In other words, the third and fourth controllable semiconductor switches can be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0028] The fifth and ninth controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the fifth and ninth controllable semiconductor switches are arranged to conduct in the same direction. In other words, the fifth and ninth controllable semiconductor switches, although in fact they are used in active clamping circuits and H-bridge circuits respectively, can also be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0029] The sixth and tenth controllable semiconductor switches can be of the same type and can be implemented in a pre-packaged module in which the sixth and tenth controllable semiconductor switches are arranged to conduct in the same direction. In other words, the sixth and tenth controllable semiconductor switches, although in fact they are used in active clamping circuits and H-bridge circuits respectively, can also be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0030] The seventh and eleventh controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the seventh and eleventh controllable semiconductor switches are arranged to conduct in the same direction. In other words, the seventh and eleventh controllable semiconductor switches, although in fact they are used in active clamping circuits and H-bridge circuits respectively, can also be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0031] The eighth and twelfth controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the eighth and twelfth controllable semiconductor switches are arranged to conduct in the same direction. In other words, the eighth and twelfth controllable semiconductor switches, although in fact they are used in active clamping circuits and H-bridge circuits respectively, can also be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0032] For example, the pre-packaged module can be a half-bridge module. In other words, each pair of controllable semiconductor switches (e.g., first and second controllable semiconductor switches, third and fourth controllable semiconductor switches, fifth and ninth controllable semiconductor switches, etc.) can be implemented as separate half-bridge modules. In this arrangement, six conventional or "off-the-shelf" pre-packaged half-bridge modules are required to implement each switch module. Such half-bridge modules may include a pair of controllable semiconductor switches defining a single arm. However, other pre-packaged modules can also be used to implement the switch modules. For example, a pre-packaged module may have two or more pairs of controllable semiconductors defining two or more arms, as long as the arm terminals are not electrically connected together (e.g., DC terminals are not interconnected). This allows multiple pairs of controllable semiconductor switches for a switch module to be implemented within the same pre-packaged module. For example, if each pre-packaged module includes a first pair of controllable semiconductor switches defining a first arm and a second pair of controllable semiconductor switches defining a second arm, only three conventional or "off-the-shelf" pre-packaged modules are needed to implement each switch module. If each pre-packaged module also includes a third pair of controllable semiconductor switches defining a third arm, only two conventional or "off-the-shelf" pre-packaged modules are needed to implement each switch module. This allows for more compact switching modules and reduces costs. Combinations of different pre-packaged modules can be used, but they will preferably all use the same type of controllable semiconductor switch.

[0033] The switching components of an H-bridge circuit include a controllable semiconductor switch and a diode connected in series: In another arrangement, the first, second, third, and fourth semiconductor devices are diodes—that is, each switching component of the H-bridge circuit may include a controllable semiconductor switch and a diode connected in series and arranged to conduct in the same direction.

[0034] In this arrangement, for convenience, the first semiconductor device is referred to as the first diode, the second semiconductor device as the second diode, the third semiconductor device as the third diode, and the fourth semiconductor device as the fourth diode.

[0035] A first controllable semiconductor switch and a first diode may be connected in series and arranged to conduct in the same direction. The first controllable semiconductor switch may be electrically connected to a first AC bridge terminal, and the first diode may be electrically connected to a first DC bridge terminal.

[0036] The second controllable semiconductor switch and the second diode can be connected in series and arranged to conduct in the same direction. The second controllable semiconductor switch can be electrically connected to the first AC bridge terminal, and the second diode can be electrically connected to the second DC bridge terminal.

[0037] The third controllable semiconductor switch and the third diode can be connected in series and arranged to conduct in the same direction. The third controllable semiconductor switch can be electrically connected to the second AC bridge terminal, and the third diode can be electrically connected to the first DC bridge terminal.

[0038] The fourth controllable semiconductor switch and the fourth diode can be connected in series and arranged to conduct in the same direction. The fourth controllable semiconductor switch can be electrically connected to the second AC bridge terminal, and the fourth diode can be electrically connected to the second DC bridge terminal.

[0039] All controllable semiconductor switches can be of the same type. In particular, it will be understood that controllable semiconductor switches of the same type can be used to implement both H-bridge circuits and active clamping circuits. All controllable semiconductor switches can have the same ratings.

[0040] For example, any suitable fully controllable semiconductor switch can be used, such as a vertical junction field-effect transistor (VJFET), an insulated gate bipolar transistor (IGBT), a high electron mobility transistor (HEMT), a bipolar junction transistor (BJT), and a gate-commutated thyristor (GCT) or a gate-turn-off thyristor (GTO). Separate diodes can optionally be connected in anti-parallel to each semiconductor switch.

[0041] Typically, each controllable semiconductor switch is turned on and off by a gating drive signal generated by a gating driver.

[0042] In a particular arrangement, for example, all the controllable semiconductor switches of the H-bridge circuit and the active clamping circuit can be implemented as IGBTs with associated anti-parallel diodes.

[0043] In one arrangement of the switching module, the first and second controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the first and second controllable semiconductor switches are arranged to conduct in the same direction. In other words, the first and second controllable semiconductor switches can be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0044] The third and fourth controllable semiconductor switches can be of the same type and can be implemented as a pre-packaged module in which the third and fourth controllable semiconductor switches are arranged to conduct in the same direction. In other words, the third and fourth controllable semiconductor switches can be implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0045] The fifth controllable semiconductor switch and the first diode can be implemented as a pre-packaged module in which the fifth controllable semiconductor switch and the first diode are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the fifth controllable semiconductor switch and the first diode, although in fact they are used in active clamping circuits and H-bridge circuits respectively, can also be implemented using controllable semiconductor switches and diodes packaged together in a conventional pre-packaged module.

[0046] The sixth controllable semiconductor switch and the second diode can be implemented as a pre-packaged module in which the sixth controllable semiconductor switch and the second diode are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the sixth controllable semiconductor switch and the second diode, although they are actually used in active clamping circuits and H-bridge circuits respectively, can also be implemented using controllable semiconductor switches and diodes packaged together in a conventional pre-packaged module.

[0047] The seventh controllable semiconductor switch and the third diode can be implemented as a pre-packaged module in which the seventh controllable semiconductor switch and the third diode are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the seventh controllable semiconductor switch and the third diode, although they are actually used in active clamping circuits and H-bridge circuits respectively, can also be implemented using controllable semiconductor switches and diodes packaged together in a conventional pre-packaged module.

[0048] The eighth controllable semiconductor switch and the fourth diode can be implemented as a pre-packaged module in which the eighth controllable semiconductor switch and the fourth diode are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the eighth controllable semiconductor switch and the fourth diode, although they are actually used in active clamping circuits and H-bridge circuits respectively, can also be implemented using controllable semiconductor switches and diodes packaged together in a conventional pre-packaged module.

[0049] The pre-packaged modules for the first and second controllable semiconductor switches can be first pre-packaged half-bridge modules, and the pre-packaged modules for the third and fourth controllable semiconductor switches can be second pre-packaged half-bridge modules. Alternatively, the first, second, third, and fourth controllable semiconductor switches can be implemented as a single pre-packaged module having two pairs of controllable semiconductor switches defining two arms, as described above. The remaining pre-packaged modules can be chopper modules, wherein each chopper module includes a controllable semiconductor switch (e.g., an IGBT and an anti-parallel diode) electrically connected in anti-series to a diode. If each pre-packaged chopper module includes a controllable semiconductor switch and a diode, five or six conventional or "off-the-shelf" pre-packaged modules are required to implement each switch module. If each pre-packaged chopper module includes two or more arms, each arm including a controllable semiconductor switch electrically connected in anti-series to a diode, fewer pre-packaged modules are required.

[0050] However, in practical arrangements, the remaining pre-packaged modules can also be half-bridge modules, wherein each pre-packaged module includes a first controllable semiconductor switch (e.g., IGBT) and a first anti-parallel diode connected in anti-series electrical connection with a second controllable semiconductor switch (e.g., IGBT) and a second anti-parallel diode. The pre-packaged half-bridge module can have two or more pairs of controllable semiconductors defining two or more arms, as described above. This allows multiple pairs of controllable semiconductor switches for the switching module to be implemented in the same pre-packaged module. One of the first and second controllable semiconductor switches in each half-bridge module (or each arm) can be disabled (e.g., by short-circuiting the gate and emitter terminals in the case of an IGBT), effectively making that switch redundant without affecting the corresponding anti-parallel diode. This allows the switching module to be implemented using, for example, six (or fewer) identical pre-packaged modules, but for a pre-packaged module with a disabled controllable semiconductor switch, only the non-disabled (or active) controllable semiconductor switch is turned on and off. Another controllable semiconductor switch will be disabled, but current can still flow through its corresponding anti-parallel diode. Combinations of different pre-packaged modules (e.g., half-bridge and chopper modules) can be used, but they will preferably all use the same type of controllable semiconductor switches.

[0051] Using MOSFETs to implement H-bridge circuits and active clamping circuits will minimize conduction losses. Using IGBTs may be cheaper, but the switching modules will have higher conduction losses. Both arrangements using MOSFETs and IGBTs will require a total of six (or fewer) pre-packaged modules.

[0052] Compared to the actual arrangement of the known switching modules described above, implementing the H-bridge circuit and active clamping circuit of the present invention using MOSFETs would require a slight increase in gating drivers (i.e., twelve instead of eight) when each switch in the H-bridge circuit is implemented as a pair of MOSFETs connected in anti-series (i.e., arranged to conduct in opposite directions) and each switch in the active clamping circuit is implemented as an IGBT with an anti-parallel diode. This is because in known switching modules, a single gating driver can be used to control the anti-series MOSFETs of each switch to turn on and off. The total chip area for each switch remains unchanged. If the H-bridge circuit and active clamping circuit are implemented using IGBTs with anti-parallel diodes (or any other suitable type of controllable semiconductor device), only eight gating drivers are needed. This is also true if the switching module is implemented using six (or fewer) identical pre-packaged modules (e.g., half-bridge modules), where one of the first and second controllable semiconductor switches in four of the pre-packaged modules is disabled (e.g., by short-circuiting the gate and emitter terminals of the IGBT if used).

[0053] Because all controllable semiconductor switches are preferably of the same type (e.g., all MOSFETs or all IGBTs or other suitable fully controllable semiconductor switches) and are preferably supplied in a pre-packaged module, they will generally have the same voltage and current ratings. In other words, the controllable semiconductor switches for active clamping circuits will now be rated to handle the full current flowing through the H-bridge circuit, whereas previously these switches might have had lower ratings. While such higher ratings are not required for normal operation (i.e., for providing energy recovery during switch module operation), higher ratings may be useful for certain situations such as fault conditions, high-frequency applications, or dynamic braking (see below), where higher currents may flow through the active clamping circuit.

[0054] The energy storage device can be a capacitor. Any suitable capacitor with any appropriate rating can be used. Alternatively, the energy storage device can be, for example, a battery or other suitable device.

[0055] The first and second AC terminals of the switching module can be electrically connected to a single coil or two or more coils connected in series or parallel.

[0056] A switching module may be associated with one or more electronic circuits (e.g., control circuitry, gating driver circuitry for driving controllable semiconductor switches, etc.). The electronic circuitry may communicate with a main controller via, for example, a fiber optic link or other electrically isolated communication channel. The electronic circuitry will typically require a power supply. In one arrangement, the power for the electronic circuitry may be provided by an energy storage device of the switching module, rather than by a separate power supply. Therefore, the switching module may include a power supply circuit (e.g., a low-voltage power supply circuit) electrically connected in parallel with the energy storage device between first and second DC clamp terminals. The power supply circuit may be electrically connected to one or more local electronic circuits. The power supply circuit may include a power converter, such as a buck power converter, to obtain a suitable output voltage from the energy storage device voltage. For example, a suitable power converter may be a DC / DC power converter, such as a forward converter or a flyback converter. The energy storage device may be charged by a DC current source through the first and second DC bridge terminals, or by a current induced in a coil electrically connected to the first and second AC bridge terminals, wherein in the latter case, the induced current will flow through one or more semiconductor devices of the H-bridge circuit and the clamp circuit. Once the energy storage device has been charged, for example by performing a pre-charging process, the power supply circuit can be used to supply power to one or more electronic circuits associated with the switching module.

[0057] The switching module may also include a battery (or a battery pack comprising multiple electrically connected batteries) electrically connected in parallel with an energy storage device between the first and second DC clamp terminals. Integrating additional energy storage beyond what is required for energy recovery can provide a distributed energy storage network for power electronic switching assemblies comprising multiple switching modules. The distributed energy storage network can be used, for example, to discharge the battery or battery pack by controlling a controllable semiconductor device via an active clamp circuit, to black-start a motor or other load electrically connected to the switching module, or for voltage regulation. The battery voltage and state of charge (SoC) of the battery can be controlled by the active clamp circuit. The active clamp circuit can be designed to match the battery voltage range across the permissible variation of the battery's SoC. In some cases, such as during overspeed conditions of a DC motor comprising multiple switching modules, and where each switching module is electrically connected to the stator coil of the DC motor, the battery can also be used to absorb excess power induced in the coils electrically connected to the first and second AC bridge terminals.

[0058] The switching module may also include a dynamic braking system electrically connected in parallel with the energy storage device between the first and second DC clamping terminals. The dynamic braking system can be of any suitable type. For example, the dynamic braking system may include a braking resistor and a controllable semiconductor switch connected in series between the first and second DC clamping terminals. The dynamic braking system may also include a diode electrically connected in parallel with the braking resistor. The dynamic braking system can be used, for example, to provide short-term power dissipation during overspeed conditions of a DC motor.

[0059] The switching module may have one or more of the following components that are electrically connected in parallel with the energy storage device: a power supply circuit, a battery for distributed energy storage, a dynamic braking system, or any other suitable circuit.

[0060] The present invention also provides a DC motor, the motor comprising: A stator with multiple stator coils; Rotor; DC current source; and A power electronic switching assembly includes n switching modules as described above, where n is an integer greater than or equal to 2. The first and second AC bridge terminals of each switching module are electrically connected to at least one corresponding stator coil. The first DC bridge terminal of the first switching module is electrically connected to a DC current source, the second DC bridge terminal of the nth switching module is electrically connected to a DC current source, and the first and second DC bridge terminals of the remaining switching modules are connected in series. For example, the first DC bridge terminal of the first switching module is electrically connected to a DC current source (e.g., electrically connected to its first DC terminal), the second DC bridge terminal of the first switching module is electrically connected to the first DC bridge terminal of the second switching module, the second DC bridge terminal of the second switching module is electrically connected to the first DC bridge terminal of the third switching module, and so on, until the second DC bridge terminal of the (n-1)th switching module is electrically connected to the first DC bridge terminal of the nth switching module, and the second DC bridge terminal of the nth switching module is electrically connected to a DC current source (e.g., electrically connected to its second DC terminal). In other words, these switching modules can be electrically connected between the DC terminals of the DC current source in a series chain structure. Two or more sets of switching modules electrically connected in a series chain structure can be electrically connected in parallel between the DC terminals of the DC current source. Switching modules can also be electrically connected together in other ways to define a power electronic switching assembly.

[0061] The stator coils can be housed in slots formed within the stator. The stator coils can be of any suitable type (e.g., single-layer, double-layer, etc.) and can be arranged around the stator with any suitable winding topology. The rotor rotates relative to the stationary stator and is separated from the stator by an air gap. The rotor can be of any suitable type (e.g., permanent magnet type or wound rotor type with any suitable excitation, such as field windings with slip rings, brushless, etc.). The rotor can be a synchronous rotor or an asynchronous / induction rotor.

[0062] A DC current source can be a power converter (e.g., an AC / DC power converter) having first and second DC terminals electrically connected to first and nth switching modules of a power electronic switching assembly, and two or more AC terminals electrically connected to an AC circuit or power grid (e.g., a three-phase power grid). For example, an AC / DC power converter can be a current source inverter or a thyristor converter (6p, 12p, etc.). Similarly, a DC current source can be a DC / DC power converter having first and second DC terminals electrically connected to first and nth switching modules of a power electronic switching assembly, and third and fourth DC terminals electrically connected to a DC circuit or an energy storage device such as a battery. A DC current source can also be another DC motor, such as a generator that provides a DC output voltage.

[0063] Each switching module may also include a controller adapted to switch the corresponding switching module according to a coil commutation process (i.e., where the current flowing through the coil reverses). Alternatively, one or more controllers may be associated with two or more switching modules, and each controller is adapted to switch the switching module according to a corresponding coil commutation process.

[0064] The coils of each switching module can be commutated, and the commutation processes of the corresponding coils can be interleaved. The stator coils of the DC motor can be arranged around the stator to provide multiple phase-shifted coil voltages—typically multi-phase. For example, a DC motor with p phases may include at least a first group of p stator coils, whose EMFs are phase-shifted by 360 / p° to each other, where p is an integer greater than or equal to 2, one cycle of the stator fundamental frequency occupies 360°, and each EMF experiences two zero crossings per cycle. The DC motor according to the invention can have any convenient number of stator coils, and therefore can have more phases, with small phase shifts between EMFs. The number of coil commutation events per stator fundamental frequency cycle is equal to twice the number of phases, thus continuous coil commutation becomes interleaved. In the case of a DC motor with many phases, several overlapping coil commutation events may be in progress at any given time.

[0065] The timing parameters of each coil commutation event can be changed or adjusted to provide closed-loop control of the voltage across the energy storage device of the active clamping circuit of the corresponding switching module.

[0066] The present invention also provides a power converter, the power converter comprising: A transformer assembly including multiple first coils; DC current source; and A power electronic switching assembly includes n switching modules as described above, where n is an integer greater than or equal to 2. The first and second AC bridge terminals of each switching module are electrically connected to the corresponding first coil of a transformer assembly. The first DC bridge terminal of the first switching module is electrically connected to a DC current source, the second DC bridge terminal of the nth switching module is electrically connected to a DC current source, and the first and second DC bridge terminals of the remaining switching modules are connected in series. For example, the first DC bridge terminal of the first switching module is electrically connected to the DC current source (e.g., electrically connected to its first DC terminal), the second DC bridge terminal of the first switching module is electrically connected to the first DC bridge terminal of the second switching module, the second DC bridge terminal of the second switching module is electrically connected to the first DC bridge terminal of the third switching module, and so on, until the second DC bridge terminal of the (n-1)th switching module is electrically connected to the first DC bridge terminal of the nth switching module, and the second DC bridge terminal of the nth switching module is electrically connected to the DC current source (e.g., electrically connected to its second DC terminal). In other words, the switching modules can be electrically connected between the DC terminals of the DC current sources in a series chain structure. Switching modules can also be electrically connected together in other ways (e.g., in series, in parallel, or in a series-parallel configuration) to define the power electronic switching assembly.

[0067] Each switching module can be electrically connected to the corresponding first coil via a capacitor.

[0068] Each switching module can be used as a DC / AC power converter, where an output current waveform is generated in each first coil. The output current waveform can have any suitable frequency, for example, approximately 1-10 kHz or higher. This allows for minimizing the size of the transformer assembly and achieving high power density.

[0069] The transformer assembly may also include multiple second coils, each associated with a first coil (e.g., having coupled primary and secondary coils). In other words, the transformer assembly may include multiple individual transformer units, each including physically separate, electromagnetically coupled primary and secondary coils. Each second coil may be electrically connected to a corresponding AC / DC power converter. Any suitable AC / DC power converter can be used. For example, each AC / DC power converter may have two AC terminals electrically connected to the corresponding second coil and two DC terminals electrically connected to the DC circuit. Alternatively, the second coil may be electrically connected to a common AC / DC power converter.

[0070] Therefore, a power converter can provide intermediate frequency electrical isolation between the DC current source and the DC circuit. The DC circuit may include one or more energy storage devices, such as capacitors.

[0071] If an AC output voltage is required, this voltage can be obtained from the DC circuit using any suitable DC / AC power converter. For example, a DC / AC power converter may have two DC terminals electrically connected to the DC circuit, and two or more AC terminals that provide the desired AC output voltage at the desired frequency (e.g., 60 Hz).

[0072] For example, each switching module can also be used as a switch-mode converter (e.g., forward or flyback converter, dual active bridge (DAB) converter, Cuk converter, single-ended primary inductor converter (SEPIC), etc.) or a resonant converter.

[0073] In the event of a failure in the H-bridge or active clamping circuit, the switching modules of the power electronic switching assembly can be bypassed. A bypass switch (e.g., a mechanical switch or a controlled semiconductor switch) can be electrically connected between the first and second DC bridge terminals of each switching module. The bypass switch will typically be open (or it will typically be open to prevent current flow through the bypass circuit between the first and second DC bridge terminals), but it can be selectively switched on (or closed) to bypass the H-bridge circuit. If one or more of the switching modules have failed and need to be bypassed, this allows the power electronic switching assembly to potentially continue operating at a slightly reduced rating. Attached Figure Description

[0074] Figure 1 This is a schematic circuit diagram showing a known switching module; Figure 2 This is a schematic circuit diagram showing the first switching module according to the present invention; Figure 3A and 3B yes Figure 2 The schematic circuit diagram of the first switching module shown; Figure 3C It can be used to achieve Figure 2 A schematic diagram of the pre-packaged module of the first switch module shown; Figure 4A and 4B This is a schematic circuit diagram of the second switch module; Figure 4C , 4D 4E and 4F are methods that can be used to achieve Figure 4A and 4B The schematic circuit diagram of the pre-packaged module of the second switch module shown; Figures 5A to 5F It is shown Figure 4A and 4B The schematic circuit diagram of the coil commutation process of the second switching module shown in the figure; Figure 6 It has a power supply circuit. Figure 4A and 4B A schematic circuit diagram of the second switch module; Figure 7 It has batteries for distributed energy storage. Figure 4A and 4B A schematic circuit diagram of the second switch module; Figure 8 It has a dynamic braking system Figure 4A and 4B A schematic circuit diagram of the second switch module; Figure 9 This is a schematic circuit diagram of a DC motor in which the power electronic switching components have multiple switching modules; Figure 10 This is a schematic circuit diagram of a power converter in which the power electronic switching components have multiple switching modules; Figure 11 yes Figure 10 The schematic circuit diagrams of the switching module, transformer unit, and AC / DC power converter of the power converter; and Figure 12 It has a bypass switch. Figure 4A and 4B The schematic circuit diagram of the second switching module. Detailed Implementation

[0075] refer to Figure 2 The switching module 1 according to the present invention includes an H-bridge circuit 2. The H-bridge circuit 2 includes: - The first and second AC bridge terminals AC1 and AC2 can be electrically connected to the corresponding coil 4. - The first and second DC bridge terminals, DC1 and DC2, can be electrically connected to a DC current source or the DC bridge terminals of another switching module. - A first switching assembly, electrically connected between the first AC bridge terminal AC1 and the first DC bridge terminal DC1, the first switching assembly including a first controllable semiconductor switch S1 and a ninth controllable semiconductor switch S9 connected in series. - A second switching assembly, electrically connected between the first AC bridge terminal AC1 and the second DC bridge terminal DC2, includes a second controllable semiconductor switch S2 and a tenth controllable semiconductor switch S10 connected in series. - A third switching assembly, electrically connected between the second AC bridge terminal AC2 and the first DC bridge terminal DC1, includes a third controllable semiconductor switch S3 and an eleventh controllable semiconductor switch S11 connected in series. - A fourth switching assembly is electrically connected between the second AC bridge terminal AC2 and the second DC bridge terminal DC2. The fourth switching assembly includes a fourth controllable semiconductor switch S4 and a twelfth controllable semiconductor switch S12 connected in series.

[0076] The first and second AC terminals AC1, AC2 of the switch module 1 are shown to be electrically connected to a single coil 4. However, the switch module 1 may be electrically connected to two or more coils connected in series or in parallel.

[0077] The switching module 1 also includes an active clamping circuit 6, which includes: - First and second DC clamping terminals DC3 and DC4, - The fifth controllable semiconductor switch S5 is electrically connected between the first DC clamping terminal DC3 and the node (or connection point) between the first and ninth controllable semiconductor switches S1 and S9. - The sixth controllable semiconductor switch S6 is electrically connected between the second DC clamping terminal DC4 and the node between the second and tenth controllable semiconductor switches S2 and S10. - The seventh controllable semiconductor switch S7 is electrically connected between the first DC clamping terminal DC3 and the node between the third and eleventh controllable semiconductor switches S3 and S11. - The eighth controllable semiconductor switch S8 is electrically connected between the second DC clamping terminal DC4 and the junction between the fourth and twelfth controllable semiconductor switches S4 and S12, and - An energy storage device (i.e., capacitor C) is electrically connected between the first and second DC clamping terminals DC3 and DC4.

[0078] The junction between the first and second controllable semiconductor switches S1 and S2 defines the first AC bridge terminal AC1, and the junction between the third and fourth controllable semiconductor switches S3 and S4 defines the second AC bridge terminal AC2.

[0079] exist Figure 2 In the switch module 1 shown, each switch assembly of the H-bridge circuit 2 includes a pair of controllable semiconductor switches (e.g., first and ninth controllable semiconductor switches S1, S9). The pair of controllable semiconductor switches in each switch assembly are connected in anti-series (i.e., arranged to conduct in opposite directions). Specifically: - The first and ninth controllable semiconductor switches S1 and S9 are connected in anti-series connection. The first controllable semiconductor switch S1 is electrically connected to the first AC bridge terminal AC1, and the ninth controllable semiconductor switch S9 is electrically connected to the first DC bridge terminal DC1. - The second and tenth controllable semiconductor switches S2 and S10 are connected in anti-series connection. The second controllable semiconductor switch S2 is electrically connected to the first AC bridge terminal AC1, and the tenth controllable semiconductor switch S10 is electrically connected to the second DC bridge terminal DC2. - The third and eleventh controllable semiconductor switches S3 and S11 are connected in anti-series connection. The third controllable semiconductor switch S3 is electrically connected to the second AC bridge terminal AC2, and the eleventh controllable semiconductor switch S11 is electrically connected to the first DC bridge terminal DC1. - The fourth and twelfth controllable semiconductor switches S4 and S12 are connected in anti-series connection. The fourth controllable semiconductor switch S4 is electrically connected to the second AC bridge terminal AC2, and the twelfth controllable semiconductor switch S12 is electrically connected to the second DC bridge terminal DC2.

[0080] All controllable semiconductor switches S1, S2, ..., S12 in switch module 1 are of the same type and have the same ratings. Figure 2 In the switch module 1 shown, all controllable semiconductor switches S1, S2, ..., S12 are MOSFETs. Each MOSFET includes a body diode as part of the MOSFET structure. It should be understood that other controllable semiconductor switches may also be used where appropriate.

[0081] The first and ninth controllable semiconductor switches S1 and S9 are connected in anti-series configuration in a common-drain configuration. The second and tenth controllable semiconductor switches S2 and S10 are connected in anti-series configuration in a common-source configuration. The third and eleventh controllable semiconductor switches S3 and S11 are connected in anti-series configuration in a common-drain configuration. The fourth and twelfth controllable semiconductor switches S4 and S12 are connected in anti-series configuration in a common-source configuration.

[0082] exist Figure 3A The same switch module 1 is shown in the figure.

[0083] refer to Figure 3B The first and second controllable semiconductor switches S1 and S2 are of the same type and are implemented in a first pre-packaged module M1 in which the first and second controllable semiconductor switches S1 and S2 are arranged to be turned on in the same direction. In other words, the first and second controllable semiconductor switches S1 and S2 are implemented using a pair of controllable semiconductor switches that are packaged together in a conventional pre-packaged module.

[0084] The third and fourth controllable semiconductor switches S3 and S4 are of the same type and are implemented in a second pre-packaged module M2 in which the third and fourth controllable semiconductor switches S3 and S4 are arranged to be turned on in the same direction. In other words, the third and fourth controllable semiconductor switches S3 and S4 are implemented using a pair of controllable semiconductor switches that are packaged together in a conventional pre-packaged module.

[0085] The fifth and ninth controllable semiconductor switches S5 and S9 are of the same type and are implemented in a third pre-packaged module M3 in which the fifth and ninth controllable semiconductor switches S5 and S9 are arranged to conduct in the same direction. In other words, the fifth and ninth controllable semiconductor switches S5 and S9, although they are actually used in the active clamping circuit 6 and the H-bridge circuit 2 respectively, are also implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0086] The sixth and tenth controllable semiconductor switches S6 and S10 are of the same type and are implemented in a fourth pre-packaged module M4 in which the sixth and tenth controllable semiconductor switches S6 and S10 are arranged to conduct in the same direction. In other words, the sixth and tenth controllable semiconductor switches S6 and S10, although they are actually used in the active clamping circuit 6 and the H-bridge circuit 2 respectively, are also implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0087] The seventh and eleventh controllable semiconductor switches S7 and S11 are of the same type and are implemented in a fifth pre-packaged module M5 in which the seventh and eleventh controllable semiconductor switches S7 and S11 are arranged to conduct in the same direction. In other words, the seventh and eleventh controllable semiconductor switches S7 and S11, although they are actually used in the active clamping circuit 6 and the H-bridge circuit 2 respectively, are also implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0088] The eighth and twelfth controllable semiconductor switches S8 and S12 are of the same type and are implemented in a sixth pre-packaged module M6 in which the eighth and twelfth controllable semiconductor switches S8 and S12 are arranged to conduct in the same direction. In other words, the eighth and twelfth controllable semiconductor switches S8 and S12, although they are actually used in the active clamping circuit 6 and the H-bridge circuit 2 respectively, are also implemented using a pair of controllable semiconductor switches packaged together in a conventional pre-packaged module.

[0089] In this arrangement, six conventional or "off-the-shelf" pre-packaged modules M1, M2, ..., M6 are required to implement the switching module. For example, the pre-packaged modules M1, M2, ..., M6 can be half-bridge modules. Figure 3C An example of a half-bridge module is shown, in which a pair of MOSFETs are connected in series and arranged to conduct in the same direction. As described above, if each pre-packaged module has two or more pairs of controllable semiconductors defining two or more arms, the switching module can be implemented using fewer pre-packaged modules, provided that the arm terminals are not electrically connected together (e.g., DC terminals are not interconnected). This allows multiple pairs of controllable semiconductor switches of the switching module to be implemented within the same pre-packaged module.

[0090] refer to Figure 4A The alternative switch module 10 according to the present invention includes an H-bridge circuit 12. The H-bridge circuit 12 includes: - The first and second AC bridge terminals AC1 and AC2 can be electrically connected to the corresponding coils 14. - The first and second DC bridge terminals, DC1 and DC2, can be electrically connected to a DC current source or the DC bridge terminals of another switching module. - A first switching assembly, electrically connected between the first AC bridge terminal AC1 and the first DC bridge terminal DC1, the first switching assembly including a first controllable semiconductor switch S1 and a first diode D1 connected in series. - A second switching assembly, electrically connected between the first AC bridge terminal AC1 and the second DC bridge terminal DC2, includes a second controllable semiconductor switch S2 and a second diode D2 connected in series. - A third switching assembly, electrically connected between the second AC bridge terminal AC2 and the first DC bridge terminal DC1, includes a third controllable semiconductor switch S3 and a third diode D3 connected in series. - A fourth switching assembly, electrically connected between the second AC bridge terminal AC2 and the second DC bridge terminal DC2, the fourth switching assembly including a fourth controllable semiconductor switch S4 and a fourth diode D4 connected in series.

[0091] The first and second AC terminals AC1, AC2 of the switch module 10 are shown to be electrically connected to a single coil 14. However, the switch module 10 may be electrically connected to two or more coils connected in series or in parallel.

[0092] The switching module 10 also includes an active clamping circuit 16, which includes: - First and second DC clamping terminals DC3 and DC4, - The fifth controllable semiconductor switch S5 is electrically connected between the first DC clamping terminal DC3 and the junction (or connection point) between the first controllable semiconductor switch S1 and the first diode D1. - The sixth controllable semiconductor switch S6 is electrically connected between the second DC clamping terminal DC4 and the junction between the second controllable semiconductor switch S2 and the second diode D2. - The seventh controllable semiconductor switch S7 is electrically connected between the first DC clamp terminal DC3 and the junction between the third controllable semiconductor switch S3 and the third diode D3. - The eighth controllable semiconductor switch S8 is electrically connected between the second DC clamp terminal DC4 and the junction between the fourth controllable semiconductor switch S4 and the fourth diode D4, and - An energy storage device (i.e., capacitor C) is electrically connected between the first and second DC clamping terminals DC3 and DC4.

[0093] The junction between the first and second controllable semiconductor switches S1 and S2 defines the first AC bridge terminal AC1, and the junction between the third and fourth controllable semiconductor switches S3 and S4 defines the second AC bridge terminal AC2.

[0094] A first controllable semiconductor switch S1 and a first diode D1 are connected in series and arranged to conduct in the same direction. The first controllable semiconductor switch S1 is electrically connected to the first AC bridge terminal AC1, and the first diode D1 is electrically connected to the first DC bridge terminal DC1.

[0095] The second controllable semiconductor switch S2 and the second diode D2 are connected in series and arranged to conduct in the same direction. The second controllable semiconductor switch S2 is electrically connected to the first AC bridge terminal AC1, and the second diode D2 is electrically connected to the second DC bridge terminal DC2.

[0096] The third controllable semiconductor switch S3 and the third diode D3 are connected in series and arranged to conduct in the same direction. The third controllable semiconductor switch S3 is electrically connected to the second AC bridge terminal AC2, and the third diode D3 is electrically connected to the first DC bridge terminal DC1.

[0097] The fourth controllable semiconductor switch S4 and the fourth diode D4 are connected in series and arranged to conduct in the same direction. The fourth controllable semiconductor switch S4 is electrically connected to the second AC bridge terminal AC2, and the fourth diode D4 is electrically connected to the second DC bridge terminal DC2.

[0098] All controllable semiconductor switches S1, S2, ..., S8 in the switching module are of the same type and have the same ratings. Figure 4A In the switch module 10 shown, all controllable semiconductor switches S1, S2, ..., S8 are IGBTs. Each IGBT is associated with an anti-parallel diode (i.e., diodes D1a, D2a, ..., D8a). It should be understood that other controllable semiconductor switches can also be used.

[0099] refer to Figure 4B The first and second controllable semiconductor switches S1 and S2 are of the same type and are implemented in a first pre-packaged module M1 in which the first and second controllable semiconductor switches S1 and S2 are arranged to be turned on in the same direction. In other words, the first and second controllable semiconductor switches S1 and S2 are implemented using a pair of controllable semiconductor switches that are packaged together in a conventional pre-packaged module.

[0100] The third and fourth controllable semiconductor switches S3 and S4 are of the same type and are implemented in a second pre-packaged module M2 in which the third and fourth controllable semiconductor switches S3 and S4 are arranged to be turned on in the same direction. In other words, the third and fourth controllable semiconductor switches S3 and S4 are implemented using a pair of controllable semiconductor switches that are packaged together in a conventional pre-packaged module.

[0101] The fifth controllable semiconductor switch S5 and the first diode D1 are implemented as a third pre-packaged module M3 in which the fifth controllable semiconductor switch S5 and the first diode D1 are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the fifth controllable semiconductor switch S5 and the first diode D1, although they are actually used in the active clamping circuit 16 and the H-bridge circuit 12 respectively, are also implemented using a controllable semiconductor switch and diode that are packaged together in a conventional pre-packaged module.

[0102] The sixth controllable semiconductor switch S6 and the second diode D2 are implemented as a fourth pre-packaged module M4 in which the sixth controllable semiconductor switch S6 and the second diode D2 are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the sixth controllable semiconductor switch S6 and the second diode D2, although they are actually used in the active clamping circuit 16 and the H-bridge circuit 12 respectively, are also implemented using a controllable semiconductor switch and diode that are packaged together in a conventional pre-packaged module.

[0103] The seventh controllable semiconductor switch S7 and the third diode D3 are implemented as a fifth pre-packaged module M5 in which the seventh controllable semiconductor switch S7 and the third diode D3 are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the seventh controllable semiconductor switch S7 and the third diode D3, although they are actually used in the active clamping circuit 16 and the H-bridge circuit 12 respectively, are also implemented using controllable semiconductor switches and diodes that are packaged together in a conventional pre-packaged module.

[0104] The eighth controllable semiconductor switch S8 and the fourth diode D4 are implemented as a sixth pre-packaged module M6 in which the eighth controllable semiconductor switch S8 and the fourth diode D4 are connected in anti-series electrical connection (i.e., arranged to conduct in opposite directions). In other words, the eighth controllable semiconductor switch S8 and the fourth diode D4, although they are actually used in the active clamping circuit 16 and the H-bridge circuit 12 respectively, are also implemented using controllable semiconductor switches and diodes that are packaged together in a conventional pre-packaged module.

[0105] In this arrangement, six conventional or "off-the-shelf" pre-packaged modules are required to implement the switching module. For example, the first and second pre-packaged modules M1 and M2 could be half-bridge modules. Figure 4CAn example of a half-bridge module is shown, in which a pair of IGBTs and an anti-parallel diode are connected in series and arranged to conduct in the same direction. Alternatively, as described above, the first, second, third, and fourth controllable switches S1, S2, ..., S4 can be implemented using a single pre-packaged module with two pairs of controllable semiconductors defining two arms, provided that the arm terminals are not electrically connected together (e.g., the DC terminals are not interconnected). The third, fourth, fifth, and sixth pre-packaged modules M3, M4, ..., M6 can be chopper modules, wherein each chopper module includes a controllable semiconductor switch (e.g., an IGBT and an anti-parallel diode) connected in anti-series to a diode. Figure 4D and 4E An example of a chopper module is shown, in which an IGBT and an anti-parallel diode are electrically connected in anti-series with the diode. The IGBT and diode are arranged to conduct in opposite directions. The third and fifth pre-packaged modules M3 and M5 can be used. Figure 4D The chopper module shown is used to implement this, and the fourth and sixth pre-packaged modules M4 and M6 can be used. Figure 4E The chopper module shown is used to implement this.

[0106] The third, fourth, fifth, and sixth pre-packaged modules M3, M4, ..., M6 can also be as follows: Figure 4C The half-bridge module shown has one IGBT in its pair disabled, thus making the switch redundant without affecting the corresponding anti-parallel diode. This is in Figure 4F As shown, one of the IGBTs is a phantom to indicate its redundancy. It can be seen that the gate and emitter terminals of the phantom IGBT are short-circuited. This allows the use of six (or fewer) identical pre-packaged half-bridge modules to implement the switching module 10—where for the third, fourth, fifth, and sixth pre-packaged modules M3, M4, ..., M6, only one IGBT is switched on and off. The other IGBT is disabled, but current can still flow through its corresponding anti-parallel diode.

[0107] like Figure 2 and Figures 3A-3C The H-bridge circuit and active clamping circuit shown are implemented using MOSFETs, which minimizes conduction losses. For example... Figures 4A-4F The IGBTs shown may be cheaper, but the switching modules will have higher conduction losses. Both arrangements using MOSFETs or IGBTs will require a total of six (or fewer) pre-packaged modules M1, M2, ..., M6.

[0108] Although the following description pertains to the switching module 10 using IGBTs, it should be understood that other types of controllable semiconductor switches may be used, for example, Figure 2 and Figures 3A-3B The MOSFET shown.

[0109] refer to Figures 5A-5F Describe the coil commutation process of the switching module 10 implemented using IGBT.

[0110] exist Figure 5A In the first stage shown, I coil =+I dc , where I coil It is the coil current, and I dc The current is supplied by a DC current source (e.g., DC current source 56 described below). The first and fourth controllable semiconductor switches S1 and S4 are turned on. All other controllable semiconductor switches are turned off. The current is... Figure 5A The direction indicated by the middle arrow is that the current flows from the first DC bridge terminal DC1 through the first diode D1, the first controllable semiconductor switch S1, the coil 14, the fourth controllable semiconductor switch S4 and the fourth diode D4 to the second DC bridge terminal DC2, and then through the coil 14.

[0111] exist Figure 5B In the second stage shown, the first and fourth controllable semiconductor switches S1 and S4 remain closed. The second, third, sixth, and seventh controllable semiconductor switches S2, S3, S6, and S7 are closed. This applies a negative voltage across coil 14. coil =-V clamp V coil It is the coil voltage, and V clamp This is the DC voltage across capacitor C in the active clamping circuit 16 (i.e., the capacitor voltage). The coil current begins to decrease, and capacitor C discharges. When the coil current reaches a threshold (e.g., I...), the discharge continues. coil =+I dc / 2), then the process transitions to Figure 5C The third stage is shown in the diagram.

[0112] In the third stage, the first controllable semiconductor switch S1 is turned off. The second, third, fourth, sixth, and seventh controllable semiconductor switches S2, S3, S4, S6, and S7 remain on. This maintains a negative voltage across coil 14. The coil current continues to decrease and approaches zero. Capacitor C charges. When the coil current reaches zero, the process transitions to... Figure 5D The fourth stage is shown in the diagram.

[0113] In the fourth stage, the second, third, fourth, sixth, and seventh controllable semiconductor switches S2, S3, S4, S6, and S7 remain on. This maintains a negative voltage across coil 14. The already negative coil current continues to become even more negative. Capacitor C discharges. When the coil current reaches a threshold (e.g., I...), ... coil =-I dc / 2), the process transitions to Figure 5EThe fifth stage is shown in the diagram.

[0114] In the fifth stage, the fourth controllable semiconductor switch S4 is turned off. The second, third, sixth, and seventh controllable semiconductor switches S2, S3, S6, and S7 remain on. This maintains a negative voltage across coil 14. The coil current continues to become more negative and approaches -I. dc Capacitor C is charged. When the coil current reaches -I... dc At that time, the process transitioned to Figure 5F The sixth stage is shown in the diagram. While switches S6 and S7 can remain on until the end of the fifth stage, they can also be disconnected during the fifth stage because their anti-parallel diodes D6a and D7a will carry current. The advantage of disconnecting switches S6 and S7 during the fifth stage is that when the coil current reaches -I... dc The fifth stage ends automatically, and if the switch remains on, the coil current will exceed -I. dc That is, there is a risk that the coil current may overshoot.

[0115] In the sixth stage, I coil =-I dc (That is, the coil current has changed from +I) dc Switching to -I dc And the second and third semiconductor switches S2 and S3 remain on.

[0116] The net charge flowing into or out of capacitor C during the coil commutation process is determined by the duration of each of the second through fifth stages. For a given clamping voltage, DC current, and coil inductance, the total duration of these stages remains constant. However, the timing of the transitions between the second and third stages, and between the fourth and fifth stages, will determine the net charge on the capacitor and thus the change in the capacitor voltage. For example, if the second and fourth stages become shorter, while the third and fifth stages become longer by the same amount, a net charge will flow into capacitor C, and the capacitor voltage at the end of the coil commutation process will be greater than it was at the beginning of the commutation process. The stage duration can be adjusted, for example, by adjusting the coil current threshold that triggers the end of each stage.

[0117] Although not shown, the coil current can be changed from -I using the corresponding coil commutation process. dc Switch to +I dc Specifically, in the first phase, I coil =-I dcThe second and third controllable semiconductor switches S2 and S3 are turned on. All other controllable semiconductor switches are turned off. Current flows through coil 14, from the first DC bridge terminal DC1 through the third diode D3, the third controllable semiconductor switch S3, coil 14, the second controllable semiconductor switch S2, and the second diode D2 to the second DC bridge terminal DC2.

[0118] In the second stage, the second and third controllable semiconductor switches S2 and S3 remain closed. The first, fourth, fifth, and eighth controllable semiconductor switches S1, S4, S5, and S8 are closed. This applies a positive voltage across coil 14. coil =+V clamp The coil current begins to become less negative, and capacitor C discharges. When the coil current reaches a threshold (e.g., I...), coil =-I dc When / 2), the process transitions to the third stage.

[0119] In the third stage, the third controllable semiconductor switch S3 is turned off. The first, second, fourth, fifth, and eighth controllable semiconductor switches S1, S2, S4, S5, and S8 remain on. This maintains a positive voltage across coil 14. The coil current continues to become less negative and approaches zero. Capacitor C charges. When the coil current reaches zero, the process transitions to the fourth stage.

[0120] In the fourth stage, the first, second, fourth, fifth, and eighth controllable semiconductor switches S1, S2, S4, S5, and S8 remain closed. This maintains a positive voltage across coil 14. The now positive coil current continues to increase. Capacitor C discharges. When the coil current reaches a threshold (e.g., I...), ... coil =+I dc When / 2), the process transitions to the fifth stage.

[0121] In the fifth stage, the second controllable semiconductor switch S2 is turned off. The first, fourth, fifth, and eighth controllable semiconductor switches S1, S4, S5, and S8 remain on. This maintains a positive voltage across coil 14. The coil current continues to increase and approaches +1. dc Capacitor C is charged. When the coil current reaches +I... dc At this point, the process transitions to the sixth stage. Although the fifth and eighth switches S5 and S8 can remain on until the end of the fifth stage, they can also be disconnected during the fifth stage because their anti-parallel diodes D5a and D8a will carry current. The advantage of disconnecting the fifth and eighth switches S5 and S8 during the fifth stage is that when the coil current reaches +I... dc The fifth stage ends automatically, and if the switch remains on, the coil current will exceed +I. dc That is, there is a risk that the coil current may overshoot.

[0122] In the sixth stage, I coil =+I dc (That is, the coil current has changed from -I) dc Switch to +I dc And the first and fourth semiconductor switches S1 and S4 remain on.

[0123] If a MOSFET is used to implement the switching module 10, the MOSFET may only need to be turned off before current stops flowing through the corresponding anti-parallel diode, and may only need to be turned on after current has started flowing through the corresponding anti-parallel diode. In other words, an idle time is typically required to allow for the coil commutation process to avoid short-circuiting the capacitor C of the active clamping circuit 16. For example, in Figure 5C In the third stage shown, but implemented using a MOSFET instead of an IGBT, it is necessary to immediately disconnect the ninth controllable semiconductor switch S9 before disconnecting the first controllable semiconductor switch S1. Disconnecting the first controllable semiconductor switch S1 turns on the body diode of the eleventh controllable semiconductor switch S11. Therefore, the eleventh controllable semiconductor switch S11 is turned on immediately after the first controllable semiconductor switch S1 is disconnected.

[0124] Switching module 10 can be associated with one or more electronic circuits (e.g., control circuitry, gating driver circuitry for driving controllable semiconductor switches, etc.). The electronic circuitry can communicate with the main controller via, for example, a fiber optic link or other electrically isolated communication channel. The electronic circuitry will typically require a power supply. In one arrangement, the power for the electronic circuitry can be provided by the capacitor C of switching module 10, rather than by a separate power supply. [Reference] Figure 6 The switching module 10 may therefore include a power supply circuit 18 (e.g., a low-voltage power supply circuit) electrically connected in parallel with the capacitor C between the first and second DC clamping terminals DC3, DC4. The power supply circuit 18 may be electrically connected to one or more local electronic circuits 20, 22. The power supply circuit may be a power converter (e.g., a buck power converter) to obtain a suitable output voltage from the capacitor voltage. For example, a suitable power converter may be a DC / DC power converter, such as a forward converter or a flyback converter. The capacitor C may be charged by a DC current source through the first and second DC bridge terminals DC1, DC2, or by a current induced in a coil 14 electrically connected to the first and second AC bridge terminals AC1, AC2, wherein in the latter case, the induced current will flow through one or more semiconductor devices of the H-bridge circuit 12 and the active clamping circuit 16. Once the capacitor C has been charged, for example by performing a pre-charging process, the power supply circuit 18 may be used to supply power to one or more electronic circuits 20, 22 associated with the switching module 10.

[0125] refer to Figure 7 The switching module 10 may also include a battery 24 (or a battery pack comprising multiple electrically connected batteries), which is electrically connected in parallel with a capacitor C between the first and second DC clamp terminals DC3, DC4. Integrating additional energy storage beyond what is required for energy recovery can provide a distributed energy storage network for a power electronic switching assembly comprising multiple electrically connected switching modules. The battery voltage and state of charge (SoC) of battery 24 can be controlled by an active clamping circuit 16. The active clamping circuit 16 can be designed to match the battery voltage range across permissible variations in the SoC of battery 24. In some cases, such as during overspeed conditions of a DC motor comprising multiple switching modules, and where each switching module is electrically connected to the stator coil of the DC motor, battery 24 can also be used to absorb excess power induced in coil 14 electrically connected to the first and second AC bridge terminals AC1, AC2. (Refer to below...) Figure 9 An example describing a DC motor.

[0126] refer to Figure 8 The switching module 10 may also include a dynamic braking system 26, which is electrically connected in parallel with the capacitor C between the first and second DC clamping terminals DC3 and DC4. The dynamic braking system 26 can be of any suitable type. For example, such as... Figure 8 As shown, the dynamic braking system 26 includes a braking resistor 28 and a controllable semiconductor switch 30 connected in series between the first and second DC clamping terminals DC3 and DC4. The dynamic braking system 26 also includes a diode 32 connected in parallel with the braking resistor 28. The dynamic braking system 26 can be used, for example, to provide short-term power dissipation during overspeed conditions of a DC motor.

[0127] refer to Figure 9 The DC motor 50 includes: - With multiple stator coils 541, 542, ..., 54 n The stator is 52, where n is an integer greater than or equal to 2. - Rotor (not shown). - DC current source 56, and - Power electronic switching assembly 58.

[0128] The power electronic switching assembly 58 includes n switching modules 101, 102, ..., 10 n As mentioned above. It should be understood that the power electronic switching assembly 58 can also be used. Figure 2 , Figure 3A and Figure 3B The switch module shown is used to implement this, where the controllable semiconductor switch is a MOSFET, or using... Figure 4A and Figure 4BThe switch module shown is used to implement this, where the controllable semiconductor switch is an IGBT. Switch modules implemented using other types of controllable semiconductor switches can also be used.

[0129] Each switch module 101, 102, ..., 10 n The first and second AC bridge terminals AC1 and AC2 are electrically connected to the corresponding stator coils 541, 542, ..., 54 n The first DC bridge terminal DC1 of the first switch module 101 is electrically connected to the first DC terminal 60 of the DC current source 56. The nth switch module 10 n The second DC bridge terminal DC2 of the first switch module 101 is electrically connected to the second DC bridge terminal DC2 of the DC current source 56, and the first and second DC bridge terminals DC1 and DC2 of the remaining switch modules are connected in series. For example, the second DC bridge terminal DC2 of the first switch module 101 is electrically connected to the first DC bridge terminal DC1 of the second switch module 102, the second DC bridge terminal DC2 of the second switch module 102 is electrically connected to the first DC bridge terminal of the third switch module, and so on, up to the (n-1)th switch module 10. (n-1) The second DC bridge terminal DC2 is electrically connected to the nth switch module 10. n The first DC bridge terminal is DC1. In other words, switch modules 101, 102, ..., 10 n It can be electrically connected between the first and second DC terminals 60 and 62 of the DC current source 56 in a series chain structure, such as... Figure 9 As shown in the image.

[0130] Figure 9 The second set of switch modules is also shown, which is connected to the first set of switch modules 101, 102, ..., 10 in a series chain link structure. n They are connected in parallel between the first and second DC terminals of the DC current source 56. In fact, three or more sets of switch modules connected in a series chain structure can be electrically connected in parallel between the first and second DC terminals of the DC current source 56.

[0131] Stator coils 541, 542, ..., 54 n They can be housed in slots formed in stator 52. Stator coils 541, 542, ..., 54 n The rotor (not shown) can be of any suitable type (e.g., single-layer, double-layer, etc.) and can be arranged around the stator to have any suitable winding topology. The rotor (not shown) rotates relative to the stationary stator 52 and is separated from the stator 52 by an air gap. As mentioned above, the rotor (not shown) can have any suitable configuration.

[0132] Figure 9The DC current source 56 shown is a power converter (e.g., an AC / DC power converter) having first and nth switch modules 101, 102 electrically connected to the power electronic switching assembly 58. n The DC current source 50 has first and second DC terminals 60, 62, and three AC terminals 64 electrically connected to an AC circuit or power grid (e.g., a three-phase power grid). Although not shown, the DC current source could also be another DC motor, such as a generator that provides a DC output voltage. The DC motor 50 can be operated as a motor or a generator. In particular, power can be supplied from the DC current source 56 to the switching modules 101, 102, ..., 103. n To drive the rotor (not shown), or the rotor can be driven to rotate (e.g., by a prime mover), and electricity can be supplied to the stator coils 541, 542, ..., 54 n Generated from switch modules 101, 102, ..., 10 n Provide DC current source 56. Other DC current sources can also be used.

[0133] Each switch module 101, 102, ..., 10 n It may also include a controller (not shown), adapted to respond to the coil commutation process (i.e., where the current flows through stator coils 541, 542, ..., 54...). n The current (which repeatedly reverses while the DC motor 50 is operating) commutates the corresponding switching module. Alternatively, one or more controllers may be associated with two or more switching modules, and each controller is adapted to commutate the switching module according to the corresponding coil commutation process. Each switching module 101, 102, ..., 10 n Stator coils 541, 542, ..., 54 n The coils can be commutated, and the commutation processes of the corresponding coils can be interleaved. The stator coils 541, 542, ..., 54 of the DC motor 50... n These can be arranged around the stator 52 to provide multiple phase-shifted coil voltages—typically multi-phase. For example, a DC motor 50 with p phases may include at least a first group of p stator coils, whose EMFs are phase-shifted by 360 / p° relative to each other, where p is an integer greater than or equal to 2, one cycle of the stator fundamental frequency occupies 360°, and each EMF experiences two zero-crossings per cycle. The DC motor 50 can have any convenient number of stator coils (i.e., n can be any suitable number), and therefore can have more phases, with small phase shifts between EMFs. The number of coil commutation events per stator fundamental frequency cycle is equal to twice the number of phases, so successive coil commutations become interleaved. At any given time, several overlapping coil commutation events may be in progress.

[0134] The timing parameters for each coil commutation event can be changed or adjusted to provide control over the corresponding switching modules 101, 102, ..., 100. n Closed-loop control of the voltage across capacitor C in the active clamping circuit 16.

[0135] refer to Figure 10 and Figure 11 The power converter 70 includes: - Transformer assembly 72, having multiple phase-coupled first coils 741, 742, ..., 74 n and multiple second coils 761, 762, ..., 76 n , - DC current source 78, and - Power electronic switching assembly 80.

[0136] The power electronic switching assembly 80 includes n switching modules 101, 102, ..., 10 n As mentioned above. It should be understood that the power electronic switching assembly 80 can also be used. Figure 2 , Figure 3A and Figure 3B The switch module shown is used to implement this, where the controllable semiconductor switch is a MOSFET, or using... Figure 4A and Figure 4B The switch module shown is used to implement this, where the controllable semiconductor switch is an IGBT. Switch modules implemented using other types of controllable semiconductor switches can also be used. Figure 11 The example shown is a switching module implemented using MOSFETs.

[0137] Each switch module 101, 102, ..., 10 n The first and second AC bridge terminals AC1 and AC2 are electrically connected to the corresponding first coils 741, 742, and 743 of the transformer assembly 72. n . Figure 11 An optional series capacitor SC is shown connected between the first AC terminal AC1 of the switch module 101 and the corresponding first coil 741. The first DC bridge terminal DC1 of the first switch module 101 is electrically connected to the first DC terminal 82 of the DC current source, and the nth switch module 10... nThe second DC bridge terminal DC2 can be electrically connected to the second DC terminal 84 of the DC current source 78, and the first and second DC bridge terminals DC1 and DC2 of the remaining switching modules are connected in series. For example, the second DC bridge terminal DC2 of the first switching module 101 is electrically connected to the first DC bridge terminal DC1 of the second switching module 102, the second DC bridge terminal DC2 of the second switching module 102 is electrically connected to the first DC bridge terminal DC1 of the third switching module, and so on, until the second DC bridge terminal DC2 of the (n-1)th switching module is electrically connected to the nth switching module 10. n The first DC bridge terminal is DC1. In other words, switch modules 101, 102, ..., 10 n It can be electrically connected between the first and second DC terminals 82 and 84 of the DC current source 78 in a series chain structure, such as... Figure 10 As shown in the image.

[0138] Each switch module 101, 102, ..., 10 n It can be used as a DC / AC power converter, where the output current waveform is in each of the first coils 741, 742, ..., 74 n The voltage is generated in the circuit. For example, to generate a positive voltage in the corresponding first coil, the first, fourth, fifth, and eighth controllable semiconductor switches S1, S4, S5, and S8 of the switching module can be turned on, while the remaining controllable semiconductor switches are turned off. To generate a negative voltage in the corresponding first coil, the second, third, sixth, and seventh controllable semiconductor switches S2, S3, S6, and S7 of the switching module can be turned on, while the remaining controllable semiconductor switches are turned off. The output current waveform can have any suitable frequency, for example, approximately 1-10 kHz or higher. This allows for minimization of the size of the transformer assembly 72 and enables high power density.

[0139] More specifically, in order to generate a positive voltage in the corresponding first coil, the first, fourth, fifth, and eighth controllable semiconductor switches S1, S4, S5, and S8 can be switched on. In this state, one of the second and third controllable semiconductor switches S2 and S3 can be switched on to short-circuit the DC current source (state A). If neither the second nor the third controllable semiconductor switches S2 and S3 are switched on (state B), the voltage at the DC current source is equal to the clamping voltage.

[0140] To generate a negative voltage in the corresponding first coil, the second, third, sixth, and seventh controllable semiconductor switches S2, S3, S6, and S7 can be switched on. In this state, one of the first and fourth controllable semiconductor switches S1 and S4 can be switched on to short-circuit the DC current source (state C). If neither the first nor the fourth controllable switches S1 and S4 are switched on (state D), the voltage at the DC current source is equal to the clamping voltage.

[0141] Therefore, the voltage at the DC current source is a square wave with an amplitude equal to the clamping voltage. The average voltage is set by the duty cycles of states A and B, and by the duty cycles of states C and D. The applied switching modes—including those for the ninth, tenth, eleventh, and twelfth controllable semiconductor switches S9, S10, ..., S12—can be optimally selected to minimize the number of switching events, and the power entering the circuit from the DC current source is regulated by controlling the average DC input voltage.

[0142] Each second coil is 761, 762, ..., 76 n Electrically connected to the corresponding AC / DC power converters 861, 862, ..., 86 n Any suitable AC / DC power converter can be used. For example, such as... Figure 10 As shown, each AC / DC power converter 861, 862, ..., 86 n It has electrical connections to the corresponding second coils 761, 762, ..., 76 n The AC power converter has two AC terminals and two DC terminals electrically connected to the DC circuit 88. The DC circuit 88 includes a capacitor 90. AC / DC power converters 861, 862, ..., 86... n Other arrangements can be used, and they can be electrically connected in different ways, for example, where the AC / DC power converters are electrically connected in, for example, series, parallel or series-parallel.

[0143] If an AC output voltage is required, it can be obtained from the DC circuit 88 using any suitable DC / AC power converter 92. For example, such as Figure 10 As shown, the DC / AC power converter 92 has two DC terminals 94, 96 electrically connected to the DC circuit 88, and three AC terminals 98 that provide the desired AC output voltage at a desired frequency (e.g., 60 Hz).

[0144] Power electronic switching components (e.g., Figure 9 The power electronic switching assembly 58 shown, or Figure 10 The power electronic switching assembly 80 shown includes switching modules 101, 102, ..., 10. n It can be bypassed in case of a fault in the H-bridge or active clamping circuit. (Reference) Figure 12A bypass switch Q1 (e.g., a mechanical switch or a controllable semiconductor switch) can be electrically connected between the first and second DC bridge terminals DC1, DC2 of each switching module 10. The bypass switch Q1 will typically be open (or it will typically be open to prevent current from flowing through the bypass circuit between the first and second DC bridge terminals), but it can be selectively switched on (or closed) to bypass the H-bridge circuit 12. This allows the power electronic switching assembly to potentially continue operating at a slightly reduced rating if one or more of the switching modules have failed and need to be bypassed. Instead of applying a direct short circuit across the first and second DC bridge terminals DC1, DC2, the bypass switch Q1 can also be electrically connected in series with an energy-absorbing device (not shown), such as a rheostat or capacitor. This can be beneficial in some applications where a direct short circuit may be undesirable.

[0145] This disclosure provides at least the following examples: Example 1. A switch module (1; 10) comprising: H-bridge circuit (2; 12), the H-bridge circuit comprising: The first and second AC bridge terminals (AC1, AC2) can be electrically connected to the corresponding coils (4; 14). The first and second DC bridge terminals (DC1, DC2) can be electrically connected to a DC current source (56; 78) or the DC bridge terminals of another switching module. The first switching assembly is electrically connected between the first AC bridge terminal (AC1) and the first DC bridge terminal (DC1). The first switching assembly includes a first controllable semiconductor switch (S1) and a first semiconductor device (S9; D1) connected in series. The second switching assembly is electrically connected between the first AC bridge terminal (AC1) and the second DC bridge terminal (DC2). The second switching assembly includes a second controllable semiconductor switch (S2) and a second semiconductor device (S10; D2) connected in series. The third switching assembly is electrically connected between the second AC bridge terminal (AC2) and the first DC bridge terminal (DC1). The third switching assembly includes a third controllable semiconductor switch (S3) and a third semiconductor device (S11; D3) connected in series. A fourth switching assembly, electrically connected between the second AC bridge terminal (AC2) and the second DC bridge terminal (DC2), comprises a fourth controllable semiconductor switch (S4) and a fourth semiconductor device (S12; D4) connected in series; and An active clamping circuit (6; 16), the active clamping circuit comprising: First and second DC clamping terminals (DC3, DC4). The fifth controllable semiconductor switch (S5) is electrically connected between the first DC clamping terminal (DC3) and the node between the first controllable semiconductor switch (S1) and the first semiconductor device (S9; D1). The sixth controllable semiconductor switch (S6) is electrically connected between the second DC clamping terminal (DC4) and the junction between the second controllable semiconductor switch (S2) and the second semiconductor device (S10; D2). The seventh controllable semiconductor switch (S7) is electrically connected between the first DC clamp terminal (DC3) and the junction between the third controllable semiconductor switch (S3) and the third semiconductor device (S11; D3). The eighth controllable semiconductor switch (S8) is electrically connected between the second DC clamp terminal (DC4) and the junction between the fourth controllable semiconductor switch (S4) and the fourth semiconductor device (S12; D4), and The energy storage device (C) is electrically connected between the first and second DC clamp terminals (DC3, DC4).

[0146] Example 2. According to the switch module (1) of Example 1, wherein the first semiconductor device is the ninth controllable semiconductor switch (S9), the second semiconductor device is the tenth controllable semiconductor switch (S10), the third semiconductor device is the eleventh controllable semiconductor switch (S11), and the fourth semiconductor device is the twelfth controllable semiconductor switch (S12).

[0147] Example 3. The switch module (1) according to Example 2, wherein: The first and second controllable semiconductor switches (S1, S2) are of the same type and are implemented as a pre-packaged module (M1) in which the first and second controllable semiconductor switches (S1, S2) are arranged to be turned on in the same direction. The third and fourth controllable semiconductor switches (S3, S4) are of the same type and are implemented as a pre-packaged module (M2) in which the third and fourth controllable semiconductor switches (S3, S4) are arranged to be turned on in the same direction. The fifth and ninth controllable semiconductor switches (S5, S9) are of the same type and are implemented as a pre-packaged module (M3) in which the fifth and ninth controllable semiconductor switches (S5, S9) are arranged to conduct in the same direction. The sixth and tenth controllable semiconductor switches (S6, S10) are of the same type and are implemented as a pre-packaged module (M4) in which the sixth and tenth controllable semiconductor switches (S6, S10) are arranged to conduct in the same direction. The seventh and eleventh controllable semiconductor switches (S7, S11) are of the same type and are implemented as a pre-packaged module (M5) in which the seventh and eleventh controllable semiconductor switches (S7, S11) are arranged to conduct in the same direction, and The eighth and twelfth controllable semiconductor switches (S8, S12) are of the same type and are implemented as a pre-packaged module (M6) in which the eighth and twelfth controllable semiconductor switches (S8, S12) are arranged to be turned on in the same direction.

[0148] Example 4. The switching module (1) according to Example 1 or Example 2, wherein all controllable semiconductor switches (S1, S2, ..., S12) of the H-bridge circuit (2) and the active clamping circuit (6) are MOSFETs.

[0149] Example 5. The switching module according to Example 4, wherein: The first and ninth controllable semiconductor switches (S1, S9) are connected in anti-series in a common-drain configuration. The second and tenth controllable semiconductor switches (S2, S10) are connected in anti-series electrical connection in a common-source configuration. The third and eleventh controllable semiconductor switches (S3, S11) are connected in anti-series electrical connection in a common-drain configuration, and The fourth and twelfth controllable semiconductor switches (S4, S12) are connected in anti-series electrical connection in a common-source configuration.

[0150] Example 6. The switching module (10) according to Example 1, wherein the first semiconductor device is a first diode (D1), the second semiconductor device is a second diode (D2), the third semiconductor device is a third diode (D3), and the fourth semiconductor device is a fourth diode (D4).

[0151] Example 7. The switch module (10) according to Example 6, wherein: The first and second controllable semiconductor switches (S1, S2) are of the same type and are implemented in a pre-packaged module (M1) in which the first and second controllable semiconductor switches (S1, S2) are arranged to be turned on in the same direction, and The third and fourth controllable semiconductor switches (S3, S4) are of the same type and are implemented as a pre-packaged module (M2) in which the third and fourth controllable semiconductor switches (S3, S4) are arranged to be turned on in the same direction. The fifth controllable semiconductor switch (S5) and the first diode (D1) are implemented in a pre-packaged module (M3) in which the fifth controllable semiconductor switch (S5) and the first diode (D1) are connected in anti-series and arranged to conduct in opposite directions. The sixth controllable semiconductor switch (S6) and the second diode (D2) are implemented in a pre-packaged module (M4) in which the sixth controllable semiconductor switch (S6) and the second diode (D2) are connected in anti-series and arranged to conduct in opposite directions. The seventh controllable semiconductor switch (S7) and the third diode (D3) are implemented in a pre-packaged module (M5) wherein the seventh controllable semiconductor switch (S7) and the third diode (D3) are connected in anti-series electrical connection and arranged to conduct in opposite directions. The eighth controllable semiconductor switch (S8) and the fourth diode (D4) are implemented as a pre-packaged module (M6) in which the eighth controllable semiconductor switch (S8) and the fourth diode (D4) are connected in anti-series and arranged to conduct in opposite directions.

[0152] Example 8. A switching module (10) according to Example 6 or Example 7, wherein all controllable semiconductor switches (S1, S2, ..., S8) of the H-bridge circuit (12) and the active clamping circuit (16) are IGBTs.

[0153] Example 9. A switching module (1; 10) according to any of the preceding examples, wherein the energy storage device is a capacitor (C).

[0154] Example 10. The switching module (10) according to any of the preceding examples further includes: a power supply circuit (18) electrically connected in parallel with the energy storage device (C) between the first and second DC clamping terminals (DC3, DC4), the power supply circuit (18) being electrically connected to one or more electronic circuits (20, 22) associated with the switching module (10).

[0155] Example 11. The switching module (10) according to any of the preceding examples further includes: a battery (24) electrically connected in parallel with the energy storage device (C) between the first and second DC clamp terminals (DC3, DC4).

[0156] Example 12. The switching module (10) according to any of the preceding examples further includes: a dynamic braking system (26) electrically connected in parallel with the energy storage device (C) between the first and second DC clamping terminals (DC3, DC4).

[0157] Example 13. A DC motor (50) comprising: It has multiple stator coils (541, 542, ..., 54) n The stator (52); Rotor; DC current source (56); and Power electronic switching assembly (58), the power electronic switching assembly (58) comprising n switching modules (101, 102, ..., 10) according to any of the foregoing examples n ), where n is an integer greater than or equal to 2, and each switch module (101, 102, ..., 10) n The first and second AC bridge terminals (AC1, AC2) are electrically connected to at least one corresponding stator coil (541, 542, ..., 54). n ), wherein the first DC bridge terminal (DC1) of the first switching module (101) is electrically connected to the DC current source (56), and the nth switching module (10) n The second DC bridge terminal (DC2) of the switch module is electrically connected to the DC current source (56), and the first and second DC bridge terminals (DC1, DC2) of the remaining switch modules are connected in series.

[0158] Example 14. The DC motor (50) according to Example 13, wherein the DC current source (56) is another DC motor or power converter, such as an AC / DC converter.

[0159] Example 15. A power converter (70) comprising: Includes multiple first coils (741, 742, ..., 74) n Transformer assembly (72); DC current source (78); and Power electronic switching assembly (80), the power electronic switching assembly (80) comprising n switching modules (101, 102, ..., 10) according to any one of Examples 1 to 9 n ), where n is an integer greater than or equal to 2, and each switch module (101, 102, ..., 10) n The first and second AC bridge terminals (AC1, AC2) are electrically connected to the corresponding first coils (741, 742, ..., 74). n ), wherein the first DC bridge terminal (DC1) of the first switch module (101) is electrically connected to the DC current source (78), and the nth switch module (10) n The second DC bridge terminal (DC2) of the switch module is electrically connected to the DC current source (78), and the first and second DC bridge terminals (DC1, DC2) of the remaining switch modules are connected in series.

Claims

1. A switching module (1; 10), including: H-bridge circuit (2; 12), the H-bridge circuit includes: The first and second AC bridge terminals (AC1, AC2) can be electrically connected to the corresponding coils (4; 14). The first and second DC bridge terminals (DC1, DC2) can be electrically connected to a DC current source (56; 78) or the DC bridge terminals of another switching module. The first switching assembly is electrically connected between the first AC bridge terminal (AC1) and the first DC bridge terminal (DC1). The first switching assembly includes a first controllable semiconductor switch (S1) and a first semiconductor device (S9; D1) connected in series. The second switching assembly is electrically connected between the first AC bridge terminal (AC1) and the second DC bridge terminal (DC2). The second switching assembly includes a second controllable semiconductor switch (S2) and a second semiconductor device (S10; D2) connected in series. The third switching assembly is electrically connected between the second AC bridge terminal (AC2) and the first DC bridge terminal (DC1). The third switching assembly includes a third controllable semiconductor switch (S3) and a third semiconductor device (S11; D3) connected in series. A fourth switching assembly, electrically connected between the second AC bridge terminal (AC2) and the second DC bridge terminal (DC2), comprises a fourth controllable semiconductor switch (S4) and a fourth semiconductor device (S12; D4) connected in series; and An active clamping circuit (6; 16), the active clamping circuit comprising: First and second DC clamping terminals (DC3, DC4). The fifth controllable semiconductor switch (S5) is electrically connected between the first DC clamping terminal (DC3) and the node between the first controllable semiconductor switch (S1) and the first semiconductor device (S9; D1). The sixth controllable semiconductor switch (S6) is electrically connected between the second DC clamping terminal (DC4) and the junction between the second controllable semiconductor switch (S2) and the second semiconductor device (S10; D2). The seventh controllable semiconductor switch (S7) is electrically connected between the first DC clamp terminal (DC3) and the junction between the third controllable semiconductor switch (S3) and the third semiconductor device (S11; D3). The eighth controllable semiconductor switch (S8) is electrically connected between the second DC clamp terminal (DC4) and the junction between the fourth controllable semiconductor switch (S4) and the fourth semiconductor device (S12; D4), and The energy storage device (C) is electrically connected between the first and second DC clamp terminals (DC3, DC4).

2. The switch module (1) according to claim 1, wherein, The first semiconductor device is the ninth controllable semiconductor switch (S9), the second semiconductor device is the tenth controllable semiconductor switch (S10), the third semiconductor device is the eleventh controllable semiconductor switch (S11), and the fourth semiconductor device is the twelfth controllable semiconductor switch (S12).

3. The switching module (1) according to claim 2, wherein: The first and second controllable semiconductor switches (S1, S2) are of the same type and are implemented as a pre-packaged module (M1) in which the first and second controllable semiconductor switches (S1, S2) are arranged to be turned on in the same direction. The third and fourth controllable semiconductor switches (S3, S4) are of the same type and are implemented as a pre-packaged module (M2) in which the third and fourth controllable semiconductor switches (S3, S4) are arranged to be turned on in the same direction. The fifth and ninth controllable semiconductor switches (S5, S9) are of the same type and are implemented as a pre-packaged module (M3) in which the fifth and ninth controllable semiconductor switches (S5, S9) are arranged to conduct in the same direction. The sixth and tenth controllable semiconductor switches (S6, S10) are of the same type and are implemented as a pre-packaged module (M4) in which the sixth and tenth controllable semiconductor switches (S6, S10) are arranged to conduct in the same direction. The seventh and eleventh controllable semiconductor switches (S7, S11) are of the same type and are implemented as a pre-packaged module (M5) in which the seventh and eleventh controllable semiconductor switches (S7, S11) are arranged to conduct in the same direction, and The eighth and twelfth controllable semiconductor switches (S8, S12) are of the same type and are implemented as a pre-packaged module (M6) in which the eighth and twelfth controllable semiconductor switches (S8, S12) are arranged to be turned on in the same direction.

4. The switching module (1) according to claim 1 or claim 2, wherein, All controllable semiconductor switches (S1, S2, ..., S12) of the H-bridge circuit (2) and the active clamping circuit (6) are MOSFETs.

5. The switching module according to claim 4, wherein: The first and ninth controllable semiconductor switches (S1, S9) are connected in anti-series in a common-drain configuration. The second and tenth controllable semiconductor switches (S2, S10) are connected in anti-series electrical connection in a common-source configuration. The third and eleventh controllable semiconductor switches (S3, S11) are connected in anti-series electrical connection in a common-drain configuration, and The fourth and twelfth controllable semiconductor switches (S4, S12) are connected in anti-series electrical connection in a common-source configuration.

6. The switching module (10) according to claim 1, wherein, The first semiconductor device is a first diode (D1), the second semiconductor device is a second diode (D2), the third semiconductor device is a third diode (D3), and the fourth semiconductor device is a fourth diode (D4).

7. The switching module (10) according to claim 6, wherein: The first and second controllable semiconductor switches (S1, S2) are of the same type and are implemented in a pre-packaged module (M1) in which the first and second controllable semiconductor switches (S1, S2) are arranged to be turned on in the same direction, and The third and fourth controllable semiconductor switches (S3, S4) are of the same type and are implemented as a pre-packaged module (M2) in which the third and fourth controllable semiconductor switches (S3, S4) are arranged to be turned on in the same direction. The fifth controllable semiconductor switch (S5) and the first diode (D1) are implemented in a pre-packaged module (M3) in which the fifth controllable semiconductor switch (S5) and the first diode (D1) are connected in anti-series and arranged to conduct in opposite directions. The sixth controllable semiconductor switch (S6) and the second diode (D2) are implemented in a pre-packaged module (M4) in which the sixth controllable semiconductor switch (S6) and the second diode (D2) are connected in anti-series and arranged to conduct in opposite directions. The seventh controllable semiconductor switch (S7) and the third diode (D3) are implemented in a pre-packaged module (M5) wherein the seventh controllable semiconductor switch (S7) and the third diode (D3) are connected in anti-series electrical connection and arranged to conduct in opposite directions. The eighth controllable semiconductor switch (S8) and the fourth diode (D4) are implemented as a pre-packaged module (M6) in which the eighth controllable semiconductor switch (S8) and the fourth diode (D4) are connected in anti-series and arranged to conduct in opposite directions.

8. The switching module (10) according to claim 6 or claim 7, wherein, All controllable semiconductor switches (S1, S2, ..., S8) of the H-bridge circuit (12) and the active clamping circuit (16) are IGBTs.

9. The switching module (1; 10) according to any of the preceding claims, wherein, The energy storage device is a capacitor (C).

10. The switching module (10) according to any of the preceding claims further comprises: A power supply circuit (18) is electrically connected in parallel with the energy storage device (C) between the first and second DC clamp terminals (DC3, DC4), and the power supply circuit (18) may be electrically connected to one or more electronic circuits (20, 22) associated with the switching module (10).

Images