Power tool and motor drive for a power tool

Abstract

A power tool and a motor driver for a power tool. The motor driver can include a motor, a power input, a switching network, and an electronic controller. The switching network is electrically connected to the power input and the motor. The switching network includes an integrated circuit. The integrated circuit includes switching elements and gate drivers for the switching elements. The electronic controller is electrically connected to the switching network. The electronic controller controls operation of the motor by providing control signals to the switching network.

Description

[0001] Related applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 681,232, filed August 9, 2024, and U.S. Provisional Patent Application No. 63 / 727,739, filed December 4, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This utility model relates to a motor driver for power tools. Background Technology

[0003] The electrical circuitry of power tools typically includes a motor, a power input unit, and a controller that provides control signals to operate the motor. There is still a need for power tool configurations that offer smaller size and weight, faster switching speeds, higher work efficiency, and improved runtime for battery-powered power tools. Utility Model Content

[0004] One embodiment provides a motor driver for a power tool motor, the motor driver comprising: a motor; a power input section; a switching network electrically connected to the power input section and the motor, the switching network including an integrated circuit including switching elements and gate drivers for the switching elements; and an electronic controller electrically connected to the switching network, the controller being configured to control the operation of the motor by providing control signals to the switching network.

[0005] One embodiment provides a motor driver for a power tool motor, the motor driver comprising: a power supply; a switching network electrically connected to the power supply, the switching network including an integrated circuit including switching elements and gate drivers for the switching elements; at least one output terminal electrically connected to the switching network; and an electronic controller electrically connected to the power supply and communicatively connected to the switching network, the controller being configured to control the operation of the switching elements by providing control signals to the switching network.

[0006] One embodiment provides a motor driver for a power tool motor, the motor driver including: a power supply; and a switching network electrically connected to the power supply, the switching network including an integrated circuit, input terminals, and output terminals, the integrated circuit including switching elements and a gate driver for the switching elements, the input terminals being electrically connected to the gate driver for the switching elements, the input terminals being configured to receive and provide the control signals to the gate driver, wherein the gate driver controls the operation of the switching elements, and the output terminals being electrically connected to the switching network, the output terminals being configured to provide the output of the switching elements to the motor.

[0007] In some aspects, the technology described in this utility model relates to an electric tool comprising: a motor; a power input section; a switching network electrically connected between the power input section and the motor, the switching network including an integrated circuit including switching elements and gate drivers for the switching elements; and an electronic controller electrically connected to the switching network and configured to operate the motor by providing control signals to the integrated circuit.

[0008] In some embodiments, the integrated circuit includes an output portion electrically connected to a terminal of the motor.

[0009] In some embodiments, the switching network is a three-phase inverter and includes a plurality of integrated circuits, the plurality of integrated circuits including three high-side switching elements and three low-side switching elements and corresponding plurality of gate drivers, wherein the integrated circuit is one of the plurality of integrated circuits, and wherein the switching element is one of the three high-side switching elements or the three low-side switching elements.

[0010] In some embodiments, the integrated circuit includes a drain terminal connected to the drain of the switching element, a source terminal connected to the source of the switching element, a control terminal connected to the control input of the gate driver, and a power terminal connected to the power input of the gate driver, wherein the control terminal is electrically connected to the output pin of the electronic controller, and the power terminal is electrically connected to an auxiliary power supply.

[0011] In some embodiments, the integrated circuit is a first integrated circuit, wherein the switching element is a first high-side wide-bandgap semiconductor field-effect transistor, wherein the gate driver is a first high-side gate driver, and wherein the switching network is a three-phase inverter comprising the first integrated circuit, the second integrated circuit, and the third integrated circuit, wherein the first integrated circuit further comprises a first low-side wide-bandgap semiconductor field-effect transistor and a first low-side gate driver for the first low-side wide-bandgap semiconductor field-effect transistor, wherein the second integrated circuit comprises a second high-side wide-bandgap semiconductor field-effect transistor, a second high-side gate driver for the second high-side wide-bandgap semiconductor field-effect transistor, a second low-side wide-bandgap semiconductor field-effect transistor, and a second low-side gate driver for the second low-side wide-bandgap semiconductor field-effect transistor, and wherein the third integrated circuit comprises a third high-side wide-bandgap semiconductor field-effect transistor, a third high-side gate driver for the third high-side wide-bandgap semiconductor field-effect transistor, a third low-side wide-bandgap semiconductor field-effect transistor, and a third low-side gate driver for the third low-side wide-bandgap semiconductor field-effect transistor.

[0012] In some embodiments, the first integrated circuit includes a positive bus terminal, a negative bus terminal, a first control terminal for the first high-side gate driver, a second control terminal for the first low-side gate driver, a power supply terminal, and a terminal. The first high-side wide-bandgap semiconductor field-effect transistor is connected between the positive bus terminal and the terminal, and the first low-side wide-bandgap semiconductor field-effect transistor is connected between the terminal and the negative bus terminal. The positive bus terminal is electrically connected to the positive bus of the power input section, and the negative bus terminal is electrically connected to the negative bus of the power input section.

[0013] In some embodiments, the power tool further includes: an input circuit electrically connected between the electronic controller and the switching network, the input circuit being configured to: receive a control signal from the electronic controller and provide the control signal to the first integrated circuit, the second integrated circuit, and the third integrated circuit.

[0014] In some embodiments, the switching network includes a plurality of integrated circuits connected in parallel between the power input and a terminal of the motor, wherein the plurality of integrated circuits includes the integrated circuit.

[0015] In some aspects, the technology described in this utility model relates to a motor drive for power tools, the motor drive comprising: a power bus; a switching network electrically connected to the power bus and including an integrated circuit, the integrated circuit including switching elements and gate drivers for the switching elements; and an electronic controller electrically connected to the switching network and configured to operate the switching elements by providing control signals to the integrated circuit.

[0016] In some embodiments, the switching network is a three-phase inverter and includes a plurality of integrated circuits, the plurality of integrated circuits including three high-side switching elements and three low-side switching elements and corresponding plurality of gate drivers, wherein the integrated circuit is one of the plurality of integrated circuits, and wherein the switching element is one of the three high-side switching elements or the three low-side switching elements.

[0017] In some embodiments, the integrated circuit includes a drain terminal connected to the drain of the switching element, a source terminal connected to the source of the switching element, a control terminal connected to the control input of the gate driver, and a power terminal connected to the power input of the gate driver, wherein the control terminal is electrically connected to the output pin of the electronic controller, and the power terminal is electrically connected to an auxiliary power supply.

[0018] In some embodiments, the integrated circuit is a first integrated circuit, wherein the switching element is a first high-side wide-bandgap semiconductor field-effect transistor, wherein the gate driver is a first high-side gate driver, and wherein the switching network is a three-phase inverter comprising the first integrated circuit, the second integrated circuit, and the third integrated circuit, wherein the first integrated circuit further comprises a first low-side wide-bandgap semiconductor field-effect transistor and a first low-side gate driver for the first low-side wide-bandgap semiconductor field-effect transistor, wherein the second integrated circuit comprises a second high-side wide-bandgap semiconductor field-effect transistor, a second high-side gate driver for the second high-side wide-bandgap semiconductor field-effect transistor, a second low-side wide-bandgap semiconductor field-effect transistor, and a second low-side gate driver for the second low-side wide-bandgap semiconductor field-effect transistor, and wherein the third integrated circuit comprises a third high-side wide-bandgap semiconductor field-effect transistor, a third high-side gate driver for the third high-side wide-bandgap semiconductor field-effect transistor, a third low-side wide-bandgap semiconductor field-effect transistor, and a third low-side gate driver for the third low-side wide-bandgap semiconductor field-effect transistor.

[0019] In some embodiments, the first integrated circuit includes a positive bus terminal, a negative bus terminal, a first control terminal for the first high-side gate driver, a second control terminal for the first low-side gate driver, a power supply terminal, and a terminal. The first high-side wide-bandgap semiconductor field-effect transistor is connected between the positive bus terminal and the terminal, and the first low-side wide-bandgap semiconductor field-effect transistor is connected between the terminal and the negative bus terminal. The positive bus terminal is electrically connected to the positive bus of the power bus, and the negative bus terminal is electrically connected to the negative bus of the power bus.

[0020] In some embodiments, the motor driver further includes: an input circuit electrically connected between the electronic controller and the switching network, the input circuit being configured to: receive a control signal from the electronic controller and provide the control signal to the first integrated circuit, the second integrated circuit, and the third integrated circuit.

[0021] In some embodiments, the switching network includes a plurality of integrated circuits connected in parallel between the power bus and a phase terminal of the motor, wherein the plurality of integrated circuits includes the integrated circuit.

[0022] In some aspects, the present invention relates to a power tool comprising: a brushless DC motor; a power input section; a first integrated circuit electrically connected between a phase terminal of the brushless DC motor and the power input section, the first integrated circuit including a first gallium nitride field-effect transistor and a first gate driver for the first gallium nitride field-effect transistor; a second integrated circuit electrically connected between the phase terminal of the brushless DC motor and the power input section and in parallel with the first integrated circuit, the second integrated circuit including a second gallium nitride field-effect transistor and a second gate driver for the second gallium nitride field-effect transistor; and an input circuit configured to receive a control signal from an electronic controller and provide the control signal to the first integrated circuit and the second integrated circuit.

[0023] In some embodiments, the first integrated circuit includes a drain terminal connected to the drain of the first gallium nitride field-effect transistor, a source terminal connected to the source of the first gallium nitride field-effect transistor, a control terminal connected to a control input of the gate driver, and a power terminal connected to a power input of the gate driver, wherein the control terminal is configured to receive the control signal from the input circuit, and the power terminal is electrically connected to an auxiliary power supply.

[0024] Other aspects of the various embodiments will become apparent from the detailed description and accompanying drawings. Attached Figure Description

[0025] Figure 1 This is a perspective view of a power tool according to some embodiments.

[0026] Figure 2 A battery pack according to some embodiments is shown.

[0027] Figure 3 It is based on some implementation methods Figure 1 A simplified block diagram of the control system of a power tool.

[0028] Figure 4 This is a simplified block diagram of an electric tool, including its electrical circuitry, according to some embodiments.

[0029] Figure 5A The following are illustrated according to some embodiments. Figure 4 An exemplary schematic diagram of a wide-bandgap transistor in the transistor shown.

[0030] Figure 5B The following are illustrated according to some embodiments. Figure 5A An exemplary schematic diagram of a parallel configuration of wide-bandgap transistors is shown.

[0031] Figure 5C The following are illustrated according to some embodiments. Figure 4 An exemplary schematic diagram of the first integrated circuit (IC) configuration shown.

[0032] Figure 5D The following are illustrated according to some embodiments. Figure 4 An exemplary schematic diagram of the second IC configuration of the integrated circuit shown.

[0033] Figure 6A The following are illustrated according to some embodiments. Figure 5D An exemplary implementation of the first configuration of the second IC configuration shown.

[0034] Figure 6B The following are illustrated according to some embodiments. Figure 5D An exemplary implementation of the second configuration 620 of the second IC configuration shown.

[0035] Figure 6C The use according to some implementation methods is shown. Figure 5D An exemplary implementation of the third configuration of the second IC configuration shown.

[0036] Figure 7 An exemplary embodiment of a first switch network configuration for a switch network 350 according to some implementations is shown.

[0037] Before explaining any embodiment in detail, it should be understood that each embodiment, in its application, is not limited to the details of the construction and arrangement of the components described in the following description or shown in the drawings. Each embodiment can be practiced or implemented in various ways. Furthermore, it should be understood that the wording and terminology used in this invention are for illustrative purposes and should not be considered restrictive. The use of "comprising," "including," or "having," and variations thereof in this invention is intended to cover the items listed thereafter and their equivalents, as well as additional items. The terms "installation," "connection," and "coupling" are used broadly and cover both direct and indirect installation, connection, and coupling. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings and may include electrical connections or electrical couplings, whether direct or indirect. Additionally, unless otherwise stated, at least when used with numerical values, approximate terms such as "about," "approximately," and "generally" may refer to within 1%, 2.5%, 5%, or 10% of said value. Detailed Implementation

[0038] Figure 1An embodiment of a power tool 100 including a brushless direct current (“BLDC”) motor is shown. The power tool 100 is, for example, an impact driver including an upper body 102, a handle 104, a battery receiving portion 106, an output drive mechanism or device 108, and a trigger 110. The power tool 100 further includes a motor, such as a motor 305 (within the housing body 102 and having a rotor and a stator). Figure 3 The rotor is coupled to a motor shaft, which is arranged to produce output outside the housing via an output drive or mechanism 108. The housing of the power tool 100 (e.g., body 102 and handle 104) is made of a durable and lightweight plastic material. The drive 108 is made of a metal (e.g., steel) output spindle. A battery receiving section 106 is configured to receive and be coupled to a battery pack, such as a battery pack 200 that supplies power to the power tool 100. Figure 2 The battery receiving portion 106 includes a connection structure for engaging a mechanism that secures the battery pack and a terminal block for electrically connecting the battery pack 200 to the power tool 100. In some embodiments, the power tool 100 may be an alternating current (AC) powered power tool that includes a rectifier for supplying DC voltage to the motor 305.

[0039] Figure 1 An impact wrench is shown; however, power tool 100 may include drills, circular saws, jig saws, band saws, reciprocating saws, screwdrivers, angle grinders, straight grinders, hammers, multi-tools, impact wrenches, rotary hammers, impact actuators, angle drills, electric ratchet wheels, electric torque wrenches, hydraulic pulse tools, hydraulic tensioning tools, bolt tightening tools, reaction arm tools, riveting tools, nail guns, staple guns, TC bolt guns, portable power supplies that use an inverter to convert battery power to AC output, etc.

[0040] Figure 2 A battery pack 200 according to some embodiments is shown. The battery pack 200 is a power tool battery pack generally used to power power tools such as power tool 100. The battery pack 200 includes a housing 205 and an interface portion 210 for connecting the battery pack 200 to a device (e.g., power tool 100). In some embodiments, the battery pack 200 includes lithium-ion battery cells. In other embodiments, the battery pack 200 may have different chemical systems, such as nickel-cadmium, nickel metal hydride, etc. In the illustrated embodiment, the battery pack 200 is an 18-volt battery pack. In other embodiments, the output voltage level of the battery pack 200 may be different. For example, the battery pack 200 may be a 4-volt battery pack, a 28-volt battery pack, a 36-volt battery pack, a 72-volt battery pack, or other voltages (the voltage referred to herein may be simply called voltage). The battery pack 200 may also have various capacities (e.g., 3, 4, 5, 6, 8, or 12 ampere-hours).

[0041] The battery pack 200 also includes terminals for connection to the power tool 100. The terminals of the battery pack 200 include positive and negative terminals for supplying and receiving power from the battery pack 200. In some embodiments, the battery pack 200 also includes data terminals for communication with the power tool 100. For example, the battery pack 200 may include a microcontroller to monitor one or more characteristics of the battery pack 200, and the data terminals can communicate with the power tool 100 regarding the monitored characteristics.

[0042] Figure 3 It is based on some implementation methods Figure 1 A simplified block diagram of the control system of the power tool 100. The control system includes a controller 300. The controller 300 is electrically and / or communicatively connected to various modules or components of the power tool 100. For example, the controller 300 shown is electrically connected to a motor 305, a power supply 310, a trigger switch 315 (connected to a trigger 320), one or more sensors or sensing circuits 325, one or more indicators 330, a user input module 335, a power input module 340, and a switch network 350 (e.g., including a single switch for a brushed motor or multiple switches for a brushless motor). The controller 300 includes a combination of hardware and software operable to control the operation of the power tool 100, monitor the operation of the power tool 100, activate one or more indicators 330 (e.g., LEDs), etc.

[0043] The controller 300 includes a plurality of electrical and electronic components that provide power, operation control, and protection to components and modules within the controller 300 and / or the power tool 100. For example, the controller 300 particularly includes a processing unit 355 (e.g., a microprocessor, microcontroller, or other suitable programmable device), a memory 360, an input unit 365, and an output unit 370. The processing unit 355 particularly includes a control unit 375, an ALU 380, and a plurality of registers 385 (in... Figure 3 The system is shown as a set of registers and is implemented using a known computer architecture (e.g., a modified Harvard architecture, von Neumann architecture, etc.). The processing unit 355, memory 360, input unit 365, and output unit 370, as well as various modules or circuits connected to the controller 300, are connected via one or more control and / or data buses (e.g., common bus 390). For illustrative purposes, the data is shown as a set of registers and is implemented using a known computer architecture (e.g., a modified Harvard architecture, von Neumann architecture, etc.). Figure 3 The diagram generally illustrates the control and / or data bus. Given the inventive features described herein, the use of one or more control and / or data buses for interconnection and communication between various modules, circuits, and components is known to those skilled in the art.

[0044] Memory 360 is a non-transitory computer-readable medium, including, for example, a program storage area and a data storage area. The program storage area and data storage area may include combinations of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, hard disk, SD card, or other suitable magnetic, optical, physical, or electronic memory devices. Processing unit 355 is connected to memory 360 and executes software instructions that can be stored in RAM of memory 360 (e.g., during execution), ROM of memory 360 (e.g., on a substantially permanent basis), or another non-transitory computer-readable medium such as another memory or disk. Software included in an implementation of power tool 100 may be stored in memory 360 of controller 300. Software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. Controller 300 is configured to retrieve from memory 360 and execute instructions related to the control processes and methods described herein. In other configurations, controller 300 includes additional, fewer, or different components.

[0045] In some embodiments, the power tool 100 includes a battery pack interface comprising a combination of mechanical components (e.g., guide rails, recesses, latches, etc.) and electrical components (e.g., one or more terminals) configured and operable to interface the power tool 100 with a power source 310 (e.g., battery pack 200) (e.g., mechanical, electrical, and communicative connection). For example, power supplied to the power tool 100 by the battery pack 200 is provided to a power input module 340 via the battery pack interface. The power input module 340 includes a combination of active and passive components to regulate or control the power received from the battery pack 200 before power is supplied to the controller 300. The battery pack interface also supplies power to a switching network 350 and to a motor 305 via the power input module 340. The battery pack interface also includes, for example, a communication line 395 for providing a communication line or link between the controller 300 and the battery pack 200.

[0046] Indicator 330 includes, for example, one or more light-emitting diodes (“LEDs”). Indicator 330 may be configured to display the status of power tool 100 or information associated with power tool 100. For example, indicator 330 may be configured to indicate measured electrical characteristics of power tool 100, the status of power tool 100, etc. User input module 335 is operatively coupled to controller 300 to, for example, select forward or reverse operating mode, torque and / or speed settings of power tool 100 (e.g., using torque and / or speed switches), etc. In some embodiments, user input module 335 includes a combination of digital and analog input or output devices required to achieve a desired operating level of power tool 100, such as one or more knobs, one or more dials, one or more switches, one or more buttons, etc.

[0047] Switching network 350 controls motor 305 based on control signals from a motor controller, such as controller 300. Switching network 350 includes a plurality of electronic switches (e.g., FETs, bipolar transistors, etc.) connected together to form an active network that controls motor 305 using pulse width modulation (PWM) signals. For example, switching network 350 may receive PWM signals from controller 300 to drive motor 305. Typically, when trigger 320 is pressed, current is supplied from power supply 310 to motor 305 via switching network 350. When trigger 320 is not pressed, current is not supplied from power supply 310 to motor 305. For example, a trigger pull sensor senses the amount and force by which trigger 320 is pulled. In some examples, the output of switching network 350 is provided to an AC outlet to power an AC device.

[0048] Motor 305 can be energized based on the state of trigger 320. Typically, motor 305 is energized when trigger 320 is activated and de-energized when trigger 320 is deactivated. In the illustrated embodiment, trigger 320 can be biased (e.g., using a biasing member such as a spring) such that when trigger 320 is released by the user, trigger 320 moves away from the handle of power tool 100 in a second direction. In some embodiments, controller 300 determines the shutdown state of power tool 100 based on a trigger pull sensor. For example, controller 300 can determine that power tool 100 is no longer operated based on the absence of input from the trigger pull sensor and / or a predetermined amount of time since the trigger pull sensor was released.

[0049] Figure 4This is a simplified block diagram of a power tool 100 including a power circuit 400, according to some embodiments. Circuit 400 includes a controller 300, a motor 305, a power supply 310, a power input section 340, and a switching network 350. The power supply 310 is electrically connected to the power input section 340. The power supply 310 provides a direct current (DC) operating voltage to the power input section 340, which is then supplied to the motor 305 (e.g., motor coils) via the switching network 350 controlled by the controller 300. Alternatively, in some embodiments, the power supply 310 is an AC power supply, and a rectifier is provided in the power input section 340 to convert the AC power into DC power supplied to the controller 300 and the switching network 350. The power input section 340 is electrically connected to the controller 300 and the switching network 350. In some embodiments, the power input section 340, the controller 300, and the switching network 350 are electrically and communicatively connected via a shared bus (not labeled). For example, the shared bus includes a power bus that comprises a positive bus and a negative bus. In this example, the power input unit 340 is connected to the switch network 350 via the shared bus. In some embodiments, the controller 300 is a controller for the entire power tool 100 (e.g., only a single controller exists in the power tool 100). Alternatively or additionally, in some embodiments, the power circuit 400 includes a housekeeping power supply to provide power to components that may not be directly involved in the main functions of the power circuit 400, such as control circuits, monitoring systems, or protection mechanisms. Alternatively, in some embodiments, the controller 300 is dedicated to the power circuit 400, and particularly to the switch network 350.

[0050] Switching network 350 is electrically connected to motor 305. In some embodiments, motor 305 is a brushless direct current (BLDC) motor. In some embodiments, power supply 310 is a battery pack, such as battery pack 200. Switching network 350 is also electrically and communicatively connected to controller 300. Switching network 350 includes at least one integrated circuit 405. An integrated circuit is an electronic device composed of a plurality of interconnected electronic components. Integrated circuit 405 is electrically connected to power input section 340. Integrated circuit 405 is configured to receive control signals from controller 300 and control the operation of motor 305. Integrated circuit 405 may include at least one gate driver 410 and at least one transistor 415. Gate driver 410 is electrically connected to transistor 415. Gate driver 410 activates transistor 415 based on input from controller 300. In some embodiments, gate driver 410 is a power amplifier that receives a low-power input from power supply 310 via controller 300 and generates a high-current drive input for transistor 415.

[0051] In some embodiments, gate driver 410 provides a pulse width modulation (PWM) signal to transistor 415 to switch transistor 415 at a specific frequency with a specific duty cycle. Alternatively, in some embodiments, gate driver 410 may send an on signal to transistor 415 so that transistor 415 remains on. When transistor 415 is on, motor 305 receives current from power supply 310. For example, the current flowing through transistor 415 flows into pole A (e.g., a phase terminal), pole B, or pole C of motor 305.

[0052] In some embodiments, transistor 415 is a wide-bandgap semiconductor field-effect transistor (FET), such as an enhancement-mode high electron mobility transistor (E-HEMT). Wide-bandgap semiconductor FETs are made of materials such as gallium nitride (GaN) (e.g., GaN FET or GaNE-HEMT), silicon carbide (SiC), etc., and have a bandgap, for example, in the range of about 3-4 electron volts (eV). Wide-bandgap semiconductors exhibit several characteristics that offer advantages over conventional field-effect transistors (FETs) (e.g., MOSFETs). In particular, wide-bandgap semiconductors can be operated at very high frequencies (e.g., 100 kHz, 200 kHz, 400 kHz, etc.) while losing less heat than MOSFETs operating at lower frequencies (e.g., 25 kHz, 50 kHz, etc.). Compared to conventional FETs, wide-bandgap semiconductors have lower on-state losses, smaller size, faster switching speeds, and less or no reverse recovery. Wide-bandgap semiconductors provide more efficient operation, thereby improving the runtime of battery-powered power tools (e.g., power tool 100).

[0053] Because wide-bandgap semiconductor transistors can operate at very high frequencies, transistor 415 provides a higher resolution signal at the output. Specifically, the switching frequency can be extended above the human hearing threshold (e.g., greater than 20 kHz to approximately 100 kHz), which can reduce auditory discomfort to the user during operation. Compared to MOSFETs, the energy storage capacity can be reduced for the same total output energy rating due to the increased frequency during operation of the wide-bandgap semiconductor. Additionally, smaller heat sinks and fans can be used because the wide-bandgap semiconductor operates more efficiently than MOSFETs, thus generating less heat during operation. Therefore, by replacing MOSFETs with wide-bandgap semiconductor devices within the switching network 350, the size and weight of components within the power tool 100 can be reduced, and the efficiency of the power circuit 400 can be improved. The switching network 350 and integrated circuit 405 are not limited to the configuration and arrangement of components described in the illustrated embodiment. The configuration of the switching network 350 and integrated circuit 405 will be described in more detail below. Unlike conventional MOSFET transistors, the high switching frequency of the wide-bandgap semiconductor also provides a small dead time (e.g., 100 nanoseconds or less) between switching from one state to the next. In some cases, reducing the amount of time between the activation and deactivation of two switching elements in a half-bridge configuration of one or more integrated circuits (i.e., dead time) reduces the harmonic content of the motor phase current, which improves conversion efficiency.

[0054] Figure 5A The following are illustrations of a method for using according to some embodiments. Figure 4 This is an exemplary schematic diagram of a discrete single-element wide-bandgap transistor 500 in transistor 415 of the power circuit 400 shown. The wide-bandgap transistor 500 is a GaN (gallium nitride) enhancement-mode high electron mobility transistor (HEMT), a type of transistor used in power electronic devices (e.g., GaN FETs). The wide-bandgap transistor 500 is a three-terminal device with a source (S), drain (D), and gate (G). The structure of the wide-bandgap transistor 500 can consist of a thin GaN layer sandwiched between two AlGaN (aluminum gallium nitride) layers. For example, the GaN layer acts as a channel for electrons to flow from the source (S) to the drain (D). The AlGaN layer acts as a barrier, reducing the electron density in the channel and allowing for better control of the electron flow. A GaN HEMT is an enhancement-mode transistor, meaning a gate voltage needs to be applied to the device to create a conductive channel in the GaN layer, allowing current to flow from the source to the drain. GaN HEMTs have high electron mobility, meaning electrons can move faster in the channel, resulting in a higher current density than conventional silicon MOSFET devices. Figure 5A An example of an integrated circuit consisting of only a single GaN FET (referred to as a discrete GaN FET) is shown. Figure 5A In the example, the integrated circuit does not include a gate driver.

[0055] Figure 5B The following are illustrated according to some embodiments. Figure 5A The diagram shows an example schematic of a parallel configuration 510 of wide-bandgap transistors 500. The parallel configuration 510 includes three (3) wide-bandgap transistors 500 connected in parallel. The drains (D) of the wide-bandgap transistors 500 are connected to each other. The sources of the wide-bandgap transistors 500 are connected to each other. The wide-bandgap transistors 500 can be driven by a gate signal provided at the gate (G) of the wide-bandgap transistors 500. Discrete GaN FETs are typically rated for blocking voltage and on-state resistance. The amount of power that can be handled by a GaN FET can be limited by the power dissipated in the GaN FET (e.g., conduction losses). The power loss generated by a GaN FET is due to the on-state resistance. Similar to a linear resistor, a GaN FET arranged in a parallel configuration will reduce power loss by reducing the on-state resistance to 1 / n (where n is the number of GaN FETs connected in parallel). Figure 5A An example of such a configuration of discrete GaN FETs in parallel is shown. In the example shown, the three GaN FETs placed in parallel result in a reduction of the on-state resistance to [value missing]. Figure 5A One-third of the on-state resistance of a discrete GaN FET.

[0056] Figure 5C The following are illustrations of a method for using according to some embodiments. Figure 4 An exemplary schematic diagram of a first integrated circuit (IC) configuration 520 of the integrated circuit 405 of the power circuit 400 shown. The first IC configuration 520 includes... Figure 5AThe transistor driver 522 (i.e., gate driver) and wide-bandgap transistor 500 are described herein. The transistor driver 522 is electrically connected to the gate (G) of the wide-bandgap transistor 500. The transistor driver 522 is configured to receive control signals from a controller, such as controller 300, and to send an on signal to the wide-bandgap transistor 500. The gate of the wide-bandgap transistor 500 is connected to the transistor driver 522. The first IC configuration 520 includes a source terminal connected to the source of the wide-bandgap transistor 500. The first IC configuration 520 includes a drain terminal connected to the wide-bandgap transistor 500. The first IC configuration 520 includes a drive terminal connected to the transistor driver 522 of the wide-bandgap transistor 500. The first IC configuration 520 includes a control terminal for providing control signals to the transistor driver 522 of the wide-bandgap transistor 500. The control terminal is connected to an output pin of the electronic controller 300 to receive control signals. The first IC configuration 520 also includes a power supply terminal for receiving control power from a power input section 340 to operate the transistor driver 522 of the wide-bandgap transistor 500. In some cases, the drive terminal is connected to the power input section 340, and the source terminal is connected to the motor output terminal. In other cases, the source terminal is connected to the power input section 340, and the drive terminal is connected to the motor output terminal.

[0057] Figure 5D The following are illustrations of a method for using according to some embodiments. Figure 4 An exemplary schematic diagram of the second IC configuration 540 of the integrated circuit 405 in the power circuit 400 shown. The second IC configuration 540 includes, as Figure 5C The first transistor driver 522A and the second transistor driver 522B (hereinafter referred to as "driver 522") described herein, and as follows Figure 5AThe first wide-bandgap transistor 500A and the second wide-bandgap transistor 500B (hereinafter referred to as "transistor 500", i.e., transistor switch) are described herein. A driver 522 is electrically connected to the gate (G) of each transistor 500. The driver 522 is configured to receive a control signal from a controller, such as controller 300, and to send an on signal to transistor 500. The source (S) of the first wide-bandgap transistor 500A is electrically connected to the drain (D) of the second wide-bandgap transistor 500B. A second IC configuration 540 includes a motor pole interface between the source (S) of the first wide-bandgap transistor 500A and the drain (D) of the second wide-bandgap transistor 500B. The motor pole interface is electrically connected to a motor pole, such as motor 305. In some embodiments, the first wide-bandgap transistor 500A may be a high-side transistor, and the second wide-bandgap transistor 500B may be a low-side transistor. For example, transistor 500 is configured as a half-bridge. In this example, the high-side transistor is electrically connected between the positive bus of the power input section 340 and a plurality of terminals of the motor 305, and the low-side transistor is electrically connected between the negative bus of the power input section 340 and a plurality of terminals of the motor 305. Furthermore, the switching network 350 includes a plurality of half-bridges. In some embodiments, the second IC configuration 540 includes a plurality of transistors 500, which include a plurality of first wide-gap transistors 500A as high-side transistors and a plurality of second wide-gap transistors 500B as low-side transistors. For example, the transistors 500 are configured as a full bridge. In another example, the second IC configuration 540 includes twelve (12) of the transistors 500.

[0058] GaN FETs can be sensitive to disturbances in the gate drive signal. In one example, an E-HEMT might require around 5 volts to conduct fully (with low losses) but may not tolerate more than 6 volts. Therefore, the signal path from the gate driver to the power device can include a very low inductance signal path. The more power devices driven from the same gate driver circuit, the more complex the parallel connection of multiple GaN FETs can become.

[0059] GaN FETs can be fabricated on silicon substrates to reduce manufacturing overhead because the large infrastructure for silicon integrated circuit fabrication already exists. Silicon substrate fabrication also allows for the integration of other silicon-based circuits, such as integrated gate drives, over-temperature detection, over-current detection, non-destructive current measurement, and short-circuit detection. Most integrated GaN FETs are easy to implement in electronic devices. Control power can be supplied to the integrated circuit along with one or two gate signals. These gate signals can be regulated by the integrated circuit and delivered to the GaN FET in an optimal manner, ensuring reliable operation. In the case of a single GaN FET, the output of the integrated GaN circuit can be a single drain connection (e.g., ...). Figures 5A-5CAlternatively, in the case of two internal GaNFETs in a half-bridge configuration, it can be a single source-drain connection (e.g., Figure 5D (Sometimes referred to as the poles of the inverter). These poles of the half-bridge are then connected to the motor leads to include the motor driver. Due to the highly integrated nature of this power device (i.e., the integrated circuit), the permissible power dissipated within the device is limited. For example... Figure 7 As shown, several half-bridges are connected in parallel (e.g., Figure 5D This provides additional benefits for power dissipation.

[0060] Parallel connection of GaN integrated circuits (e.g., such as Figure 7 As shown, this can lead to the sharing of load current through each GaN device (e.g., a GaN FET or GaN IC). When power devices are connected in parallel, current sharing has two components: static and dynamic. Static current sharing is defined as the extent to which parallel power devices share current when they are fully conducting or “on.” Dynamic current sharing is defined as the extent to which parallel power devices share current when they switch from being blocked or “off” to conducting or “on” and vice versa. One factor affecting static current sharing is the on-state resistance, or RDS-on, of the GaN device. Most E-HEMTs exhibit a positive temperature coefficient on RDS-on. This means that as the device carrying the maximum current heats up, its RDS-on also increases, thus reducing the amount of current flowing through the device. In this way, when it comes to static current sharing, the device tends to self-balance.

[0061] Factors influencing dynamic current sharing include gate threshold, VGS(th), transconductance (Gm), and IC / device layout. VGS(th) is the voltage level at the device gate when the device begins to turn on and conduct current. When considering parallel GaN devices (e.g., parallel-connected GaN E-HEMT devices), the device with the lowest VGS(th) will turn on first. Transconductance can be considered as the current gain rating of a GaN device and is the mechanism that relates the applied gate voltage of a GaN device to the current it can conduct. In a parallel GaN device configuration, the single device with the highest transconductance can conduct the maximum current. In GaN devices, transconductance has a negative temperature coefficient, meaning that as the device heats up, the transconductance, or "current gain," decreases, thereby reducing the amount of current being conducted by that device. The current path between the gate driver and the GaN FET, or the gate-source loop as known in the art, can also affect dynamic current sharing. For example, for two GaN FETs, if the conductor distance between the gate driver and the GaN FET is different, this can cause the GaN FET with the higher output to experience current sharing imbalance, overheating, or premature failure. Due to the high-speed switching characteristics of GaN FETs, symmetry when connecting multiple devices to the same gate driver can contribute to dynamic current sharing. Having an integrated gate driver in the same IC as the GaN FET makes symmetry easier to achieve, for example, because there is no longer an additional route for the connection between the gate driver and the GaN FET, and the gate-source loop is roughly the same for all GaN FETs because they use the same package.

[0062] As discussed in this invention, in order to minimize dynamic current sharing, the circuit can be combined with an integrated GaN FET (e.g., including a GaN gate driver) at the power stage input, power stage output, or both, as shown below.

[0063] Figures 6A-6C This illustrates a technique for reducing dynamic current sharing when multiple GaN FETs are connected in parallel between the power input and one terminal of the motor 305. Figure 6A It shows the use of Figure 4 The power circuit 400 shown Figure 5DAn exemplary embodiment of the first configuration 600 of the second IC configuration 540 shown is illustrated. The first configuration 600 includes two (2) configurations of the input circuit 605 and the second IC configuration 540, for example, the second IC configuration 540A and the second IC configuration 540B. The input circuit 605 is configured to receive control signals from a controller (such as controller 300). The input circuit 605 provides control signals to driver 522. Specifically, the input circuit 605 may receive a single signal for controlling two FETs of the first IC configuration 540A and a single signal for controlling two FETs of the second IC configuration 540B. The input circuit 605 may provide a separate signal for each FET of the first IC configuration 540A and the second IC configuration 540B. The input circuit 605 is also configured to provide power to the second IC configuration 540A and the second IC configuration 540B from a power source such as power supply 310. The input circuit may include, for example, an amplifier circuit that allows amplification and splitting of the control signals, such that a single signal can be provided to two outputs. Input circuit 605 minimizes the risk of dynamic current sharing in parallel integrated GaN power devices (such as second IC configuration 540A and second IC configuration 540B). Driver 522 of second IC configuration 540A and second IC configuration 540B is configured to receive control signals and control the operation of transistor 500 to provide an output for operating a motor (such as motor 305). Second IC configuration 540A and second IC configuration 540B each include a motor pole interface between the source (S) and drain (D) of transistor 500, and the motor pole interfaces of second IC configuration 540A and second IC configuration 540B are electrically connected to each other. The output from the motor pole outlet is provided to the pole of a motor, such as motor 305. In some embodiments, Figure 4 The switching network 350 includes, for example, Figure 6A The second IC configuration 540A and the second IC configuration 540B are configured in the middle.

[0064] Figure 6B It shows that Figure 5D The second IC configuration 540 shown is used for Figure 4An exemplary embodiment of a second configuration 620 of the power circuit 400 shown is described. The second configuration 620 includes two (2) configurations of an output circuit 625 and a second IC configuration 540, for example, a second IC configuration 540A and a second IC configuration 540B. Drivers 522 of the second IC configurations 540A and 540B are configured to receive control signals from a controller (such as controller 300). Drivers 522 control the operation of transistors 500 in the second IC configurations 540A and 540B. Each of the second IC configurations 540A and 540B includes an output between the source (S) and drain (D) of transistor 500. The outputs of the second IC configurations 540A and 540B are electrically connected to the output circuit 625. The output circuit 625 includes a motor pole output that provides the outputs of the second IC configurations 540A and 540B to a motor (such as motor 305). The output circuit 625 minimizes the risk of dynamic current sharing in parallel integrated GaN power devices, such as the second IC configuration 540A and the second IC configuration 540B.

[0065] Figure 6C It shows the use of Figure 5D The second IC configuration 540 shown is used for Figure 4 An exemplary embodiment of the third configuration 640 of the power circuit 400 shown is illustrated. The third configuration 640 includes two (2) configurations of an input circuit 605, an output circuit 625, and a second IC configuration 540, such as second IC configuration 540A and second IC configuration 540B. The input circuit 605 is configured to receive control signals from a controller (such as controller 300). The input circuit 605 provides control signals to a driver 522. The input circuit 605 is also configured to provide power to the second IC configuration 540A and second IC configuration 540B from a power source such as power supply 310. The driver 522 of the second IC configuration 540A and second IC configuration 540B is configured to receive control signals and control the operation of transistor 500 to provide outputs. The outputs of the second IC configuration 540A and second IC configuration 540B are each disposed between the source (S) and drain (D) of transistor 500. The outputs of the second IC configuration 540A and second IC configuration 540B are electrically connected to the output circuit 625. The output circuit 625 includes providing the outputs of the second IC configuration 540A and the second IC configuration 540B to the motor pole output of a motor (such as motor 305).

[0066] Figure 7 It shows the use of Figure 5D The second IC configuration 540 shown is used for Figure 4An exemplary embodiment of the first switch network configuration 700 of the switch network 350 shown is presented. The first switch network configuration 700 is a three-phase inverter configuration. The first switch network configuration 700 includes a switch network 350. The switch network 350 includes three (3) configurations (e.g., six (6) switching elements) of a second IC configuration 540, such as, for example, second IC configuration 540A, second IC configuration 540B, and second IC configuration 540C. The drains (D) of the respective first wide-bandgap transistors 500A of the second IC configurations 540A, 540B, and 540C are connected to each other. The sources of the respective second wide-bandgap transistors 500B of the second IC configurations 540A, 540B, and 540C are electrically connected to each other. The common drain (D) and source (S) are connected to the positive and negative terminals of the battery pack, respectively, to receive power from the battery pack 200. Driver 522 is configured to receive control signals from a controller, such as controller 300, and to send an on signal to transistor 500. Second IC configurations 540A, 540B, and 540C include motor pole interfaces between the source (S) of a corresponding first wide-bandgap transistor 500A and the drain (D) of a corresponding second wide-bandgap transistor 500B. The respective motor pole interfaces of second IC configurations 540A, 540B, and 540C are each electrically connected to a pole of a motor (such as motor 305).

[0067] Therefore, the various embodiments described in this utility model provide a power converter device with a wide bandgap semiconductor.

Claims

1. A power tool characterized by comprising: include: motor; Power input section; A switching network electrically connected between the power input section and the motor, the switching network including an integrated circuit including a switching element and a gate driver for the switching element; and An electronic controller electrically connected to the switching network and configured to operate the motor by providing control signals to the integrated circuit.

2. The power tool of claim 1, wherein, The integrated circuit includes an output portion that is electrically connected to a terminal of the motor.

3. The power tool of claim 1, wherein, The switching network is a three-phase inverter and includes a plurality of integrated circuits, the plurality of integrated circuits including three high-side switching elements and three low-side switching elements and a corresponding plurality of gate drivers, wherein the integrated circuit is one of the plurality of integrated circuits, and wherein the switching element is one of the three high-side switching elements or the three low-side switching elements.

4. The power tool of claim 1, wherein, The integrated circuit includes a drain terminal connected to the drain of the switching element, a source terminal connected to the source of the switching element, a control terminal connected to the control input of the gate driver, and a power terminal connected to the power input of the gate driver, wherein the control terminal is electrically connected to the output pin of the electronic controller, and the power terminal is electrically connected to an auxiliary power supply.

5. The power tool of claim 4, wherein, The drain terminal is electrically connected to the positive bus of the power input section, and the source terminal is electrically connected to the motor terminal.

6. The power tool of claim 4, wherein, The source terminal is electrically connected to the negative bus of the power input section, and the drain terminal is electrically connected to the motor terminal.

7. The power tool of claim 1, wherein, The integrated circuit is a first integrated circuit, wherein the switching element is a first high-side wide-bandgap semiconductor field-effect transistor, and wherein the gate driver is a first high-side gate driver. The switching network described therein is a three-phase inverter comprising the first integrated circuit, the second integrated circuit, and the third integrated circuit. The first integrated circuit further includes a first low-side wide-bandgap semiconductor field-effect transistor and a first low-side gate driver for the first low-side wide-bandgap semiconductor field-effect transistor. The second integrated circuit includes a second high-side wide-bandgap semiconductor field-effect transistor, a second high-side gate driver for the second high-side wide-bandgap semiconductor field-effect transistor, a second low-side wide-bandgap semiconductor field-effect transistor, and a second low-side gate driver for the second low-side wide-bandgap semiconductor field-effect transistor. The third integrated circuit includes a third high-side wide-bandgap semiconductor field-effect transistor, a third high-side gate driver for the third high-side wide-bandgap semiconductor field-effect transistor, a third low-side wide-bandgap semiconductor field-effect transistor, and a third low-side gate driver for the third low-side wide-bandgap semiconductor field-effect transistor.

8. The power tool of claim 7, wherein, The first integrated circuit includes a positive bus terminal, a negative bus terminal, a first control terminal for the first high-side gate driver, a second control terminal for the first low-side gate driver, a power supply terminal, and a terminal. The first high-side wide-bandgap semiconductor field-effect transistor is connected between the positive bus terminal and the terminal, and the first low-side wide-bandgap semiconductor field-effect transistor is connected between the terminal and the negative bus terminal. The positive bus terminal is electrically connected to the positive bus of the power input section, and the negative bus terminal is electrically connected to the negative bus of the power input section.

9. The power tool as claimed in claim 7, characterized in that, Further includes: An input circuit, electrically connected between the electronic controller and the switching network, is configured as follows: The electronic controller receives control signals and provides the control signals to the first integrated circuit, the second integrated circuit, and the third integrated circuit.

10. The power tool of claim 9, wherein, Further includes: An output circuit, electrically connected between the switching network and the motor, is configured as follows: The system receives outputs from the first integrated circuit, the second integrated circuit, and the third integrated circuit, and provides the outputs to the motor.

11. The power tool of claim 1, wherein, The switching element is a gallium nitride enhanced high electron mobility transistor.

12. The power tool of claim 1, wherein, The switching network includes a plurality of integrated circuits connected in parallel between the power input section and a terminal of the motor, wherein the plurality of integrated circuits includes the integrated circuit.

13. A motor driver for an electric power tool, characterized by comprising: The motor driver includes: Power busbar; A switching network electrically connected to the power bus and including an integrated circuit, the integrated circuit including switching elements and gate drivers for the switching elements; and An electronic controller electrically connected to the switching network and configured to operate the switching elements by providing control signals to the integrated circuit.

14. The motor driver of claim 13, wherein, The switching network is a three-phase inverter and includes a plurality of integrated circuits, the plurality of integrated circuits including three high-side switching elements and three low-side switching elements and a corresponding plurality of gate drivers, wherein the integrated circuit is one of the plurality of integrated circuits, and wherein the switching element is one of the three high-side switching elements or the three low-side switching elements.

15. The motor driver of claim 13, wherein, The integrated circuit includes a drain terminal connected to the drain of the switching element, a source terminal connected to the source of the switching element, a control terminal connected to the control input of the gate driver, and a power terminal connected to the power input of the gate driver, wherein the control terminal is electrically connected to the output pin of the electronic controller, and the power terminal is electrically connected to an auxiliary power supply.

16. The motor driver of claim 15, wherein, The drain terminal is electrically connected to the positive bus of the power bus, and the source terminal is electrically connected to the phase terminal of the motor.

17. The motor driver of claim 15, wherein, The source terminal is electrically connected to the negative bus of the power bus, and the drain terminal is electrically connected to the phase terminal of the motor.

18. The motor driver of claim 13, wherein, The integrated circuit is a first integrated circuit, wherein the switching element is a first high-side wide-bandgap semiconductor field-effect transistor, and wherein the gate driver is a first high-side gate driver. The switching network described therein is a three-phase inverter comprising the first integrated circuit, the second integrated circuit, and the third integrated circuit. The first integrated circuit further includes a first low-side wide-bandgap semiconductor field-effect transistor and a first low-side gate driver for the first low-side wide-bandgap semiconductor field-effect transistor. The second integrated circuit includes a second high-side wide-bandgap semiconductor field-effect transistor, a second high-side gate driver for the second high-side wide-bandgap semiconductor field-effect transistor, a second low-side wide-bandgap semiconductor field-effect transistor, and a second low-side gate driver for the second low-side wide-bandgap semiconductor field-effect transistor. The third integrated circuit includes a third high-side wide-bandgap semiconductor field-effect transistor, a third high-side gate driver for the third high-side wide-bandgap semiconductor field-effect transistor, a third low-side wide-bandgap semiconductor field-effect transistor, and a third low-side gate driver for the third low-side wide-bandgap semiconductor field-effect transistor.

19. The motor driver of claim 18, wherein, The first integrated circuit includes a positive bus terminal, a negative bus terminal, a first control terminal for the first high-side gate driver, a second control terminal for the first low-side gate driver, a power supply terminal, and a terminal. The first high-side wide-bandgap semiconductor field-effect transistor is connected between the positive bus terminal and the terminal, and the first low-side wide-bandgap semiconductor field-effect transistor is connected between the terminal and the negative bus terminal. The positive bus terminal is electrically connected to the positive bus of the power bus, and the negative bus terminal is electrically connected to the negative bus of the power bus.

20. The motor driver of claim 18, wherein, Further includes: An input circuit, electrically connected between the electronic controller and the switching network, is configured as follows: The electronic controller receives control signals and provides the control signals to the first integrated circuit, the second integrated circuit, and the third integrated circuit.

21. The motor driver of claim 13, wherein, The switching element is a gallium nitride enhanced high electron mobility transistor.

22. The motor driver of claim 13, wherein, The switching network includes a plurality of integrated circuits connected in parallel between the power bus and a phase terminal of the motor, wherein the plurality of integrated circuits includes the integrated circuit.

23. A power tool characterized by include: Brushless DC motor; Power input section; A first integrated circuit is electrically connected between the phase terminal of the brushless DC motor and the power input section. The first integrated circuit includes a first gallium nitride field-effect transistor and a first gate driver for the first gallium nitride field-effect transistor. The second integrated circuit is electrically connected between the phase terminal of the brushless DC motor and the power input section and is connected in parallel with the first integrated circuit. The second integrated circuit includes a second gallium nitride field-effect transistor and a second gate driver for the second gallium nitride field-effect transistor. and An input circuit is configured to receive control signals from an electronic controller and provide the control signals to the first integrated circuit and the second integrated circuit.

24. The power tool of claim 23, wherein, The first integrated circuit includes a drain terminal connected to the drain of the first gallium nitride field-effect transistor, a source terminal connected to the source of the first gallium nitride field-effect transistor, a control terminal connected to the control input of the gate driver, and a power terminal connected to the power input of the gate driver, wherein the control terminal is configured to receive the control signal from the input circuit, and the power terminal is electrically connected to an auxiliary power supply.

25. The power tool of claim 24, wherein, The drain terminal is electrically connected to the positive bus of the power input section, and the source terminal is electrically connected to the phase terminal.

26. The power tool of claim 24, wherein, The source terminal is electrically connected to the negative bus of the power input section, and the drain terminal is electrically connected to the phase terminal.

27. The power tool of claim 23, wherein the first and second electrical conductors are disposed on a surface of the housing. The first gallium nitride field-effect transistor and the second gallium nitride field-effect transistor are gallium nitride enhancement-mode high electron mobility transistors.

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