Motor commutation waveform generating circuit

Abstract

The motor commutation waveform generating circuit includes an edge detection circuit for accessing a sensing signal of a motor to derive a clock signal indicating a commutation switching point of the motor; an angle cutting circuit controlled by the clock signal to output an angle indication pulse indicating a rotation angle of the motor; a synthesized wave generating circuit for sequentially changing a waveform voltage corresponding to a required angle using the angle indication pulse and segmenting the output; and a signal combining circuit controlled by the clock signal to combine the waveform voltage signals generated by the synthesized wave generating circuit to obtain a plurality of synthesized waveforms for the driving control system of the motor to modulate the pulse width for driving control. The motor commutation waveform generating circuit can be applied to any waveform synthesizing circuit for motor driving system commutation, without using micro control unit (MCU) algorithm or microprocessor (CPU) calculation, and is low in cost and easy to integrate with high and low voltage circuits.

Description

Technical Field

[0001] This invention relates to a motor commutation waveform generation circuit, and more particularly, to a commutation waveform generation circuit that generates a commutation waveform for motor drive, which is then pulse-modulated and applied to motor drive control. Background Technology

[0002] A frequency converter (VFD) is a type of adjustable speed drive system that uses variable frequency drive technology to change the frequency and amplitude of the operating voltage of an AC motor, thereby smoothly controlling the speed and torque of the AC motor. The most common type is an AC / AC converter where both the input and output are AC. Before the advent of VFDs, applications requiring motor speed adjustment needed to use a DC motor, or a VS motor with a built-in coupler to reduce the actual speed of the motor during operation. VFDs simplify these processes, reduce equipment size, and significantly lower maintenance rates.

[0003] Inverters also allow motors to operate in a pre-planned manner, further reducing mechanical and electronic stress. For example, when a typical inverter starts, the speed changes continuously, while the acceleration changes discontinuously. In conveyor belt applications, the S-curve function can be used to make the acceleration during acceleration and deceleration also change continuously, making the acceleration and deceleration process smoother and reducing gaps in the conveyor belt during acceleration and deceleration.

[0004] There are many ways to drive motors with frequency converters, the simplest of which is V / f pure quantity control. In this method, the inverter's output voltage is directly proportional to the output frequency, making it suitable for constant torque loads. The relationship between voltage and frequency is called the V / f curve. Some V / f control inverters have a curve where the output voltage is proportional to the square of the output frequency, or multiple settable V / f curves. Two commonly used drive technologies are vector control and direct torque control (DTC). These adjust the magnitude and angle of the output voltage based on the output current and motor speed to precisely control the motor's flux and torque.

[0005] The output of the frequency converter is generated by using an inverter to output AC voltage in the form of pulse width modulation (PWM). Among them, sine wave PWM is the most direct way to adjust the motor voltage and frequency. If the reference signal exceeds the carrier wave, a high potential is output, and vice versa. This generates an output signal whose pulse width changes with time. After filtering, the output signal is close to a sine wave.

[0006] Existing frequency converters require an embedded system with a microprocessor or digital signal processor at its core to control the converter's operation. The relevant programs reside in the firmware of the microprocessor or digital signal processor. The frequency converter provides display information, variables, and function block parameters, which users can modify through an operator or communication to monitor and protect the frequency converter and the driven motors and equipment.

[0007] Adjusting the magnitude and angle of the motor speed output voltage requires mathematical algorithm calculations through the internal circuitry of a microprocessor (CPU) or microcontroller unit (MCU) to generate a commutation waveform, which is then provided to the motor drive control system for pulse width modulation and drive control. The internal circuit calculation process generates computational delays, and the overall circuit integration is relatively difficult and costly. Summary of the Invention

[0008] The purpose of this invention is to provide a motor commutation waveform generation circuit, a novel arbitrary waveform synthesis circuit for commutation in motor drive systems, which does not use microcontroller unit (MCU) algorithms or microprocessor (CPU) for calculation, and is low in cost and easy to integrate with high and low voltage circuits.

[0009] Another objective of this invention is to provide a motor commutation waveform generation circuit for three-phase motors. This circuit is easily integrated to provide a synthesized commutation waveform signal and can be directly integrated with a drive circuit system. Similarly, it is easily applied to sensorless motor drive systems, directly detecting the output voltage of the drive motor to obtain the synthesized commutation waveform. It can also be applied to stepper motor drive systems, where two synthesized sine waves with a 90-degree phase difference are used for micro-stepping control, and the angle resolution is easily expanded and improved.

[0010] One embodiment of the present invention provides a motor commutation waveform generation circuit for generating a corresponding composite commutation waveform of a motor, which is provided to the drive control system of the motor for pulse width modulation control. The circuit includes: an edge detection circuit for receiving the sensing signal of the motor and deriving a clock signal indicating the commutation switching point of the motor; an angle cutting circuit controlled by the clock signal to generate an angle indicator pulse wave indicating the rotation angle of the motor; a composite waveform generation circuit that uses the angle indicator pulse wave to sequentially change the waveform voltage corresponding to the required angle and outputs it in segments; and a signal merging circuit controlled by the clock signal to merge the waveform voltage signals generated by the composite waveform generation circuit to obtain multiple composite waveforms for use by the drive system of the motor for control.

[0011] In one embodiment of the present invention, the sensing signal of the motor is a Hall signal output by at least two Hall elements.

[0012] In one embodiment of the present invention, the sensing signal of the motor is the drive output voltage signal of the motor.

[0013] In one embodiment of the present invention, the edge detection circuit includes: a plurality of resonators, an OR gate and a D flip-flop. The plurality of resonators are used to perform pulse edge detection on each of the sensing signals after the sensing signal of the motor is received, and output the pulse edge detection signal to the OR gate to control the circuit clock of the D flip-flop.

[0014] In one embodiment of the present invention, the angle cutting circuit includes: two capacitors controlled by a switch controlled by the clock signal to perform constant current charging and discharging, respectively obtaining a first voltage and a second voltage, which are triangular wave voltage waveforms relative to the clock signal;

[0015] Two reference voltage generation modules, controlled by a clock signal-controlled switch, respectively input the first voltage and the second voltage to output waveform signals representing a first x-voltage and a second x-voltage that are multiples of the first voltage and the second voltage, respectively, where 0 <x<1;

[0016] Two comparators are input to the first voltage and the first x voltage, and the second voltage and the second x voltage, respectively. After comparison, the angle indication pulse is output through a latch.

[0017] In one embodiment of the present invention, the reference voltage generation module is used to change different x-multiples by utilizing the variation signal of the angle indicator pulse.

[0018] In one embodiment of the present invention, each of the reference voltage generation modules includes an operational amplifier, a resistor divider network, a multiplexer, and a shift register. The first voltage and the second voltage are transmitted through the operational amplifier and the resistor divider network to generate multiple voltage values ​​of varying magnitudes to the multiplexer. The angle indicator pulse variation signal is transmitted through the shift register to control the multiplexer to switch different reference potentials and output waveform signals of the first x voltage and the second x voltage.

[0019] In one embodiment of the present invention, the synthesized wave generation circuit includes an operational amplifier and a sin value resistor voltage divider network. The operational amplifier uses a 2V voltage and the voltage divided by the sin value resistor voltage divider network to control the multiplexer to switch different reference potentials and output six different output waveform voltage signals by means of the angle indicator pulse variation signal through the shift register.

[0020] In one embodiment of the present invention, the signal combining circuit includes multiple sets of multiplexers and shift registers. The shift registers are controlled by the clock signal to control the multiplexers to combine the waveform voltage signals generated by the composite waveform generation circuit to obtain multiple composite waveforms for use by the drive system of the motor.

[0021] In one embodiment of the present invention, the multiplexer of the signal combining circuit takes in the sensing signal of the motor to synchronize the plurality of synthesized waveforms with the sensing signal of the motor by an arbitrary angle.

[0022] The motor commutation waveform generation circuit provided in this embodiment of the invention is used to generate commutation waveforms for motor drive. After pulse modulation, these waveforms are applied to the motor drive control system, such as sine waves or composite waveforms used in field-oriented control (FOC), or arbitrary composite commutation waveforms. In practice, it can receive Hall effect sensor signals, or obtain the waveform directly by comparing the output voltage of the drive stage without a sensor. For example, it can obtain the clock signal for every 60 degrees of rotation of a three-phase motor. Each two clock intervals are further subdivided into smaller angle indication signals to generate the basic shape of the waveform within each 60-degree interval. Finally, these signals are combined to form an arbitrary composite waveform of 360 degrees, which is then supplied to the motor drive system for commutation.

[0023] The advantages of this invention are that it is applied to an arbitrary waveform synthesis circuit for commutation in a motor drive system, without using MCU algorithms or CPU calculations, resulting in low cost and easy integration with high and low voltage circuits. When applied to three-phase motors, it is easy to integrate the circuit, providing commutation synthesis waveform signals and can be directly integrated with the drive circuit system. Similarly, it is easily applied to sensorless motor drive systems, directly detecting the output voltage of the drive motor to obtain the commutation synthesis waveform.

[0024] The motor commutation waveform generation circuit provided in this embodiment of the invention can also be applied to a stepper motor drive system. Two synthesized sine waves with a 90-degree phase difference are applied to the control of micro-stepping, and the angle resolution can be easily expanded and improved. Attached Figure Description

[0025] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] Figure 1 This is a schematic diagram of a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram of the Hall element sensing signal input and angle cutting circuit in a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of a sensorless motor drive system and an angle cutting circuit in a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of the edge detection circuit in the motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0030] Figure 5 This is a schematic diagram of a reference voltage generation module in a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0031] Figure 6 for Figure 2 The diagram shows a pulse signal in the motor commutation waveform generation circuit.

[0032] Figure 7 This is a schematic diagram of the synthesized wave generation circuit in a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0033] Figure 8 This is a table showing the correspondence between sin values ​​of a sine wave and resistance.

[0034] Figure 9 This is a schematic diagram of the Sin voltage value.

[0035] Figure 10 This is a schematic diagram of the signal merging circuit in a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0036] Figure 11 This is a schematic diagram of the circuit simulation results of the motor commutation waveform generation circuit provided in one embodiment of the present invention, with a three-phase Hall signal input.

[0037] Figure 12 for Figure 11 A schematic diagram illustrating its derivative applications.

[0038] Figure 13 This is a schematic diagram of the simulation results of a motor commutation waveform generation circuit provided in one embodiment of the present invention to drive the output voltage signal input.

[0039] Figure 14 This is a schematic diagram of a synthetic wave generation circuit for a stepper motor application, provided in one embodiment of the present invention.

[0040] Figure 15 For application Figure 14 A schematic diagram of a signal combining circuit.

[0041] Figure 16 This is a schematic diagram of the circuit simulation results for a stepper motor application of a motor commutation waveform generation circuit provided in one embodiment of the present invention.

[0042] [Explanation of Labels in the Attached Image]

[0043] 100: Motor

[0044] 101, 102, 103: Hall effect elements

[0045] 200: Edge detection circuit

[0046] 201, 202, 203: Resonator

[0047] 220: OR Gate

[0048] 230:D trigger

[0049] 300: Angle Cutting Circuit

[0050] 301, 302: Inverters

[0051] 311, 312, 331, 332: Switches

[0052] 333: Operational Amplifier

[0053] 334: Multiplexer

[0054] 335: Shift Register

[0055] 336: Resistor voltage divider network

[0056] 341, 342: Comparators

[0057] 350: Latch

[0058] 400: Synthetic Wave Generation Circuit

[0059] 410: Operational amplifier

[0060] 420: Sin value resistor voltage divider network

[0061] 421, 422, 423, 424, 425, 426: Multiplexers

[0062] 431, 432, 433, 434, 435, 436: Shift registers

[0063] 500: Signal combining circuit

[0064] 511, 512, 513: Multiplexers

[0065] 521, 522, 523: Shift registers

[0066] H: Sensing signal

[0067] H1, H2, H3: Hall signals

[0068] U, V, W: Voltage signals

[0069] SCK: Clock Signal

[0070] HA: Angle Clock Signal

[0071] SVCK: Angle Indicator Pulse

[0072] PH: Synthetic waveform

[0073] Ca, Cb: Capacitance

[0074] VA: First voltage

[0075] VB: Second voltage

[0076] VAx: First x-voltage

[0077] VBx: Second x voltage

[0078] I1, I2: Constant current source

[0079] Vxgen: Reference Voltage Generation Module

[0080] R: Resistance

[0081] SU1, SU2, SU3, SD1, SD2, SD3: Waveform voltage signals

[0082] PH1, PH2, PH3: Composite waveforms of sine waves Detailed Implementation

[0083] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. The accompanying drawings are simplified schematic diagrams, which are only used to illustrate the basic structure of the present invention. Therefore, only the components related to the present invention are marked in these drawings. The components shown are not drawn according to the number, shape, size ratio, etc. of the implementation. The actual specifications and dimensions of the components in the implementation are a selective design, and the layout of the components may be more complex.

[0084] The following descriptions of the embodiments are with reference to the accompanying drawings, illustrating specific embodiments in which the invention may be practiced. Directional terms used in this invention, such as "up" and "down," are only for reference to the accompanying drawings. Therefore, the directional terms used are for illustration and understanding of this application, and not for limiting this application. Furthermore, in the specification, unless explicitly stated otherwise, the word "comprising" will be understood to mean including the stated components, but does not exclude any other components.

[0085] The motor commutation waveform generation circuit provided in this embodiment of the invention is used to generate commutation waveforms for motor drive. It can be applied to two-phase, three-phase, or multi-phase motor drive control systems and is applied to the motor drive control system after pulse modulation. It receives a Hall element sensing signal input, or directly compares the output voltage of the drive stage without a sensor to obtain a clock signal for each 60-degree rotation of a three-phase motor. Each two clock intervals are further subdivided into smaller angle indication signals, which are then used to generate the basic shape of the waveform within each 60-degree interval. These signals are then combined to form an arbitrary composite waveform of 360 degrees, generating the corresponding motor commutation composite waveform, such as a sine wave or a composite waveform used by FOC (Focus on the Motor Control System). This waveform is then provided to the motor drive control system for pulse width modulation and control of the motor drive system for commutation.

[0086] See Figure 1 This is a schematic diagram of a motor commutation waveform generation circuit provided in one embodiment of the present invention. The motor commutation waveform generation circuit provided in one embodiment of the present invention includes: an edge detection circuit 200, used to receive a sensing signal H from a motor 100 and derive a clock signal SCK to indicate the commutation switching point of the motor 100; an angle cutting circuit 300, controlled by the clock signal SCK to generate an angle indication pulse SVCK indicating the rotation angle of the motor 100; a composite waveform generation circuit 400, using the angle indication pulse SVCK to sequentially change the waveform voltage corresponding to the required angle and output it in segments; and a signal combining circuit 500, controlled by the clock signal SCK, to combine the waveform voltage signals generated by the composite waveform generation circuit 400 to obtain multiple composite waveforms PH for use by the drive system of the motor 100 for control.

[0087] The motor commutation waveform generation circuit provided in this embodiment of the invention features real-time and fast response, and eliminates the delay of MCU algorithms or CPU calculations. It uses simple circuitry and capacitors, resulting in low circuit cost and easy integration with high and low voltage circuits. The circuit resolution can be easily expanded, allowing for precise segmentation into smaller motor rotation angles. Detailed implementation instructions are as follows:

[0088] See Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the Hall element sensing signal input and angle cutting circuit 300 in a motor commutation waveform generation circuit provided in one embodiment of the present invention. Figure 3 This is a schematic diagram of a sensorless motor drive system and angle cutting circuit 300 in a motor commutation waveform generation circuit provided in one embodiment of the present invention. In one embodiment, the sensing signal H of the motor 100 is the Hall signal H1, H2, H3 output by at least two Hall elements (in this embodiment, three Hall elements 101, 102, and 103) (e.g., Figure 2(as shown); or in another embodiment, the sensing signal H of the motor 100 is the drive output voltage signal UVW of the motor 100 (as shown). Figure 3 As shown), the drive output voltage signal UVW replaces Hall elements 101, 102, 103 and their Hall signals H1, H2, H3, and the rest of the subsequent embodiments are applied in the same way. The following embodiments use the Hall signals H1, H2, H3 output by the three Hall elements 101, 102, 103 as illustrative examples.

[0089] See Figure 4 This is a schematic diagram of the edge detection circuit 200 in the motor commutation waveform generation circuit provided in one embodiment of the present invention. After the edge detection circuit 200 receives the sensing signal H from the motor 100, each sensing signal H (H1, H2, H3) undergoes pulse edge detection by a resonator 201, 202, 203, and is output to an OR gate 220 to control the circuit clock of a D flip-flop 230, thus deriving the clock signal SCK. Since the detected Hall signal point is the switching point where the motor 100 rotates 60 degrees, the derived clock signal SCK generates an angle clock signal HA representing 60 degrees per half cycle (e.g., ...). Figure 6 (Diagram of pulse wave signal).

[0090] See Figure 2 and Figure 3 The angle cutting circuit 300 includes two capacitors, Ca and Cb, and switches 311 and 312 controlled by the clock signal SCK perform constant current charging and discharging to obtain a first voltage VA and a second voltage VB. The triangular wave voltage waveforms of the two voltages relative to the clock signal SCK are shown in the figure. Figure 6 (See the schematic diagram of the pulse signal). The aforementioned clock signal SCK controls two inverters 301 and 302 connected in series, which in turn control switches 311 and 312 of two constant current sources I1 and I2 to charge and discharge capacitors Ca and Cb at constant current. Typically, the constant current source I2 is twice the constant current source I1, ensuring that the charging and discharging times of capacitors Ca and Cb are the same.

[0091] Please refer to the following: Figure 2 and Figure 3, two reference voltage generation modules Vxgen are controlled by switches 331 and 332 controlled by the clock signal SCK, and input the first voltage VA and the second voltage VB respectively, and output waveform signals of a first x voltage VAx and a second x voltage VBx that are x times the first voltage VA and the second voltage VB respectively, where 0 < x < 1; two comparators 341 and 342 input the first voltage VA and the first x voltage VAx, and the second voltage VB and the second x voltage VB respectively, and after comparison, output an angle indication pulse SVCK through a latch 350 (in practice, an inverter can be added at the output end, and the inverted signal is convenient for design and interpretation), such as Figure 6 the pulse signal schematic diagram).

[0092] Please refer to again Figure 5 , Figure 5 Taking the input of the first voltage VA as an example, the reference voltage generation module Vxgen can change different x multiples by using the variation signal of the angle indication pulse SVCK. Each reference voltage generation module Vxgen includes an operational amplifier 333, a resistor voltage division network 336, a multiplexer 334 and a shift register 335. The first voltage VA and the second voltage VB pass through the operational amplifier 333 and then generate multiple voltage values of different magnitudes at the nodes of the resistor voltage division network 336 (formed by multiple identical resistors R in series) to the multiplexer 334. The variation signal of the angle indication pulse SVCK controls the multiplexer 334 to switch different reference potentials through the shift register 335 and output the waveform signals of the first x voltage VAx and the second x voltage VBx. For example, for six equal divisions, x = 5 / 6, 4 / 6, 3 / 6, 2 / 6, 1 / 6.

[0093] The angle indication pulse SVCK controls the multiplexer 334 to switch different reference potentials and output the first x voltage VAx at different times (the rotation angle position of the motor 100) in sequence. Since the first voltage VA represents the time when the motor rotates 60 degrees, and is represented by the magnitude of the voltage value, the resistors R are designed in a geometric progression. For example, for 12 equal divisions, there are 12 resistors R, and each resistor R represents 5 degrees. The corresponding voltages are changed from top to bottom to the multiplexer 334, that is, 12 equal components of 5 degrees each are sequentially cut out, and 11 such angle indication pulses SVCK can be obtained.

[0094] Please refer to Figure 6 , the angle clock signal HA obtained by the edge detection circuit 200 represents 60 degrees per half cycle, and the clock signal SCK is an indication short pulse signal for every 60 degrees. For example, by using a six-equal division cutting method, 5 indication signals of the angle indication pulse SVCK can be obtained within every 60 degrees.

[0095] Please refer to Figure 7The synthesized wave generation circuit 400 includes an operational amplifier 410, a sin-value resistor divider network 420, six multiplexers 421, 422, 423, 424, 425, 426, and shift registers 431, 432, 433, 434, 435, 436. The operational amplifier 410 uses a 2V voltage and the voltage divided by the sin-value resistor divider network 420 to control the multiplexers 421, 422, 423, 424, 425, 426 to switch different reference potentials and output six different output waveform voltage signals SU1, SU2, SU3, SD1, SD2, SD3.

[0096] The six multiplexers 421, 422, 423, 424, 425, 426 and the shift registers 431, 432, 433, 434, 435, 436 each represent the change in time when the motor rotates 100 degrees by 60 degrees, and are SU1-3 and SD1-3; SU1-3 are used to generate the corresponding 180-degree range of the sine wave, and are designed to lag by 30 degrees, in the following order: 30-90 degrees (SU1, rising), 90-150 degrees (SU2, falling), 150-210 degrees (SU3, falling). (Shrinking rapidly); while SD1 to SD3 are used to generate the other 180-degree range of the corresponding sine wave, in the following order: 210-270 degrees (SD1, falling), 270-330 degrees (SD2, rising), 330-300 degrees (SD3, rising rapidly). By controlling the multiplexers 421, 422, 423, 424, 425, and 426 with different reference voltages in the sequence SU1 rising → SU2 falling → SU3 falling rapidly → SD1 falling → SD2 rising → SD3 rising rapidly, the waveform can be obtained. Further applications can also generate arbitrary waveforms. Taking the synthesized waveform used by FOC as an example, it can be obtained by only changing the reference rising / falling potentials of SU1 / SU2 and SD1 / SD2.

[0097] Figure 8 A table showing the correspondence between sinusoidal wave sin values ​​and resistance. Figure 9 This is a schematic diagram of the Sin voltage value. Based on this, a 420-degree resistive voltage divider network is designed. VR1 is used as the reference value. SU1 to 3 receive Sin values ​​from 30 degrees to 210 degrees (including VR1.* and part of VR0.* reference values) to obtain voltage values ​​that change every 5 degrees. SD1 to 3 receive Sin values ​​from 210 degrees to 30 degrees (VR0.* and part of VR1.* reference values) and reflect the voltage values ​​that change every 5 degrees in a mirror-downward manner.

[0098] Please see Figure 10The signal combining circuit 500 is a three-phase / 6-group signal combining circuit. The signal combining circuit 500 includes multiple multiplexers 511, 512, 513 and shift registers 521, 522, 523. The shift registers 521, 522, 523 are controlled by the clock signal SCK, which in turn controls the multiplexers 511, 512, 513 to combine the waveform voltage signals SU1, SU2, SU3, SD1, SD2, SD3 generated by the synthesized waveform generation circuit 400 to obtain multiple synthesized waveforms PH (sine wave synthesized waveforms PH1, PH2, PH3) for use by the drive system of the motor 100. The signal merging circuit 500 merges six sets of partial sine wave signals representing 60 degrees to obtain three output signals PH1 to PH3 for use in the three-phase motor drive system control. The clock signal SCK is the clock signal for every 60 degrees of rotation of the motor 100. With the shift registers 521, 522, and 523 controlling the outputs SU1→SU2→SU3→SD1→SD2→SD3 in sequence, the synthesized sine wave waveforms PH1, PH2, and PH3 can be obtained.

[0099] In this circuit, multiplexers 511, 512, and 513 of the signal merging circuit 500 input the sensing signal H from the motor 100 to synchronize multiple synthesized waveforms PH (sine wave synthesized waveforms PH1, PH2, and PH3) with an arbitrary angle lagging behind the sensing signal H from the motor 100. For example... Figure 11 As shown, H1_EN / H2_EN / H3_EN then incorporates the relevant information of Hall signals H1, H2, and H3, causing the synthesized sine wave waveforms PH1, PH2, and PH3 to lag behind and synchronize with them by 30 degrees. This is applicable to general drive operations. Alternatively, it can be further made to lag behind by any angle for synchronization. Theoretically, this can be applied to motor drive control where the motor magnetic field lags or leads.

[0100] Please see Figure 11 This is the actual circuit simulation result of a three-phase motor using Hall effect signals as sensing signals. v(h1) / v(h2) / v(h3) are the three Hall effect input signals, v(sck) is the clock signal for detecting changes in the Hall effect signals, and v(svck) divides the time of change of the two Hall effect signals into 12 equal parts, with each interval being a 60-degree rotation angle. Each division is an indication signal for a 5-degree angle change. Of course, the division can be designed according to requirements, such as 6 equal parts for 10 degrees, 24 equal parts for 2.5 degrees, and so on. By using v(sck) and v(svck) indicator signals to sequentially switch different reference potentials, a sine wave shape is generated. The sine wave is divided into six two-intervals at 60 degrees. Within these six intervals, corresponding reference potential switching values ​​are given according to the rise and fall of the sine wave to obtain the v(ph1) / v(ph2) / v(ph3) sine wave waveform. The difference from the Hall signal can be designed to lag by 30 degrees to drive the three-phase motor for general commutation operation control.

[0101] Similarly, changing the corresponding six interval potential switching values ​​can generate waveforms such as v(ph1f) / v(ph2f) / v(ph3f), which are then applied to the FOC motor drive control system.

[0102] Furthermore, such as Figure 12 As shown, it is Figure 11 In terms of derivative applications, the technology in this case can arbitrarily change the corresponding six interval potential switching values ​​to generate composite waveforms such as v(ph1g) / v(ph2g) / v(ph3g). This can be used to analyze the impact of different composite waveforms on motor commutation operations and motor control circuits.

[0103] Please see Figure 13 This is a schematic diagram of the circuit simulation results of using the drive output voltage signal UVW as input in one embodiment of the present invention. It is applied to, for example, sensorless motor drive control systems, i.e., input signals without Hall elements or encoders. Instead, three drive stage output voltages, v(u) / v(v) / v(w), can be used as inputs, and a resistor network circuit is used to detect and compare the voltages, producing a Hall-like signal after internal processing of v(cpu) / v(cpv) / v(cpw). The remaining signals are the v(sck) signal and v(svck) indicator signal, as described above, to sequentially switch different reference potentials, generating a sine wave shape lagging 30 degrees and a synthesized waveform using FOC.

[0104] The embodiments of the present invention can also be applied to stepper motors, which control rotation at a frequency of one step. To meet the requirement of smooth rotation, micro-stepping control technology has been maturely developed, and it is similar to a sine wave shape. By applying the aforementioned technical methods, the embodiments of the present invention can be extended to such stepper motor applications.

[0105] Revise Figure 7 and Figure 10 This allows for the creation of a stepper motor synthesized wave generation circuit 400 and a signal merging circuit 500. For example... Figure 14 and Figure 15 As shown, by modifying the generation method of sine wave synthesis, the arrangement of sine values ​​varies from 0 to 90 degrees, 90 to 180 degrees, 180 to 270 degrees, and 270 to 360 degrees. Then, by changing the merging order, we obtain the following sine wave synthesized waveforms: PH1 is SD2→SU1→SU2→SD1, and PH2 is SU1→SU2→SD1→SD2, meaning they differ by 90 degrees. Of course, changing this order can yield other phase differences, such as lagging or leading.

[0106] In this circuit, the multiplexers 511 and 512 of the signal merging circuit 500 take in the sensing signal H from the motor 100 to synchronize multiple synthesized waveforms PH (sine wave synthesized waveforms PH1 and PH2) with an arbitrary angle lagging behind the sensing signal H from the motor 100. For example... Figure 15 As shown, HA_EN then incorporates the angle clock signal HA and related information, causing the synthesized sine wave waveforms PH1 and PH2 to lag behind and synchronize with it by 30 degrees. This is applicable to general drive operations. Alternatively, it can be further made to lag behind by any angle for synchronization, which can be applied to the motor drive control theory of motor magnetic field lag or lead.

[0107] Furthermore, finer segmentation angles result in smaller step angles and more precise positioning. Additionally, several clock cycles can be combined to form a sine wave, increasing the resolution angle. The above example uses two frequency cycles to form a sine wave, i.e., 360 degrees / (4 half-cycles * 12 segments) = 7.5 degrees. In applications, the resolution can be as fine as 360 degrees / (12 half-cycles * 24 segments) = 1.25 degrees.

[0108] Please see Figure 16 This is the circuit simulation result for a stepper motor application. As shown in the figure, HA is the stepper square wave signal. It is designed to generate a sine wave composite waveform ph1 in two signal cycles, and generate another sine wave composite waveform ph2 that lags behind the sine wave composite waveform ph1 by 90 degrees. The difference between the two sine wave composite waveforms is 90 degrees, which can be used for micro-stepping control of the stepper motor.

[0109] Using the method described in the previous embodiment, the waveforms are divided into 12 equal parts, as shown in VA / VAx and VB / VBx. A sine wave generation technique is applied to synthesize the sine wave waveforms ph1 and ph2, making them 90 degrees out of phase. Figure 16 The waveform shown is the reference waveform for completing the motor drive control of the microstepping machine.

[0110] The motor commutation waveform generation circuit provided in this embodiment of the invention can be applied to two-phase, three-phase, or multi-phase motor drive control systems. It receives signals from sensing components such as Hall effect sensors or output voltage signals from the drive stage, generates corresponding motor commutation composite waveforms, such as sine waves or composite waveforms used by FOC, and provides them to the motor drive control system for pulse width modulation and drive control.

[0111] In applications, it can be used with Hall effect sensors (HAL ICs) to output sine waves or FOC composite waveforms. After being modulated by the PWM signal of the control system, it controls the rotation of the motor. This is similar to the common method of using an MCU to capture Hall signals, perform mathematical algorithms on them, and generate commutation waveforms. However, the circuit of this invention is simple and inexpensive, and can respond to motor rotation in real time, unaffected by the performance of the MCU instruction cycle. It can also be directly integrated with high-voltage drive stage circuits on a single chip. It is easily applied to motor drive systems, including Hall effect sensor signal input detection, comparison of a 60-degree clock signal, segmentation into very small angle indication signals, and finally, the generation of a composite waveform for application.

[0112] In addition, when applied to applications that do not use Hall elements, the output voltage of the motor drive stage can be directly detected. By simply adding some comparison circuits, the above operation can be performed, comparing the frequency at a 60-degree angle, dividing it into very small angle indication signals, and finally producing a synthesized waveform for application, such as a sine wave or a synthesized waveform used by FOC. This can be directly applied to sensorless motor drive systems or used in combination with systems that have Hall signal detection.

[0113] Applied to stepper motor drive systems, by changing the waveform reference voltage and combination method, it can generate two sine waves with a 90-degree phase difference commonly used in micro-stepping. Furthermore, the resolution can be easily expanded, allowing it to be applied to very small step angles.

[0114] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A motor commutation waveform generation circuit, used to generate a corresponding synthesized commutation waveform of a motor, and provide it to the drive control system of the motor for pulse width modulation control, characterized in that, include: An edge detection circuit is used to receive the sensing signal of the motor and output a clock signal to indicate the commutation switching point of the motor. An angle cutting circuit, controlled by the clock signal, generates an angle indicator pulse to indicate the rotation angle of the motor. A synthesized wave generation circuit uses the angle indication pulse to sequentially change the waveform voltage corresponding to the required angle and outputs it in segments; and A signal combining circuit, controlled by the clock signal, combines the waveform voltage signals generated by the synthesized waveform generation circuit to obtain multiple synthesized waveforms for use by the motor drive system.

2. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The sensing signal of the motor is a Hall signal output by at least two Hall elements.

3. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The sensing signal of the motor is the drive output voltage signal of the motor.

4. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The edge detection circuit includes: multiple resonators, an OR gate, and a D flip-flop. The multiple resonators are used to perform pulse edge detection on each of the sensing signals after the motor is connected, and output the pulse edge detection signal to the OR gate to control the clock of the D flip-flop.

5. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The angle cutting circuit includes: Two capacitors are charged and discharged at a constant current by a switch controlled by the clock signal, resulting in a first voltage and a second voltage, which are triangular wave voltage waveforms relative to the clock signal. Two reference voltage generation modules, controlled by a clock signal-controlled switch, respectively input the first voltage and the second voltage to output waveform signals representing a first x-voltage and a second x-voltage that are multiples of the first voltage and the second voltage, respectively, where 0 <x<1; Two comparators are input to the first voltage and the first x voltage, and the second voltage and the second x voltage, respectively. After comparison, the angle indication pulse is output through a latch.

6. The motor commutation waveform generation circuit as described in claim 5, characterized in that, The reference voltage generation module is used to utilize the angle indicator pulse variation signal to change different x-multiples.

7. The motor commutation waveform generation circuit as described in claim 5, characterized in that, Each of the reference voltage generation modules includes an operational amplifier, a resistor divider network, a multiplexer, and a shift register. The first voltage and the second voltage are processed by the operational amplifier and then by the resistor divider network to generate multiple voltage values ​​of varying magnitudes to the multiplexer. The angle indicator pulse variation signal is controlled by the shift register to switch different reference potentials and output waveform signals of the first x voltage and the second x voltage.

8. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The synthesized wave generation circuit includes an operational amplifier and a sin value resistor voltage divider network, six multiplexers and a shift register. The operational amplifier uses a 2V voltage and the voltage divided by the sin value resistor voltage divider network to control the multiplexers to switch different reference potentials and output six different output waveform voltage signals by using the shift register to control the change signal of the angle-indicating pulse.

9. The motor commutation waveform generation circuit as described in claim 1, characterized in that, The signal combining circuit includes multiple sets of multiplexers and shift registers. The shift registers are controlled by the clock signal to control the multiplexers to combine the waveform voltage signals generated by the composite waveform generation circuit to obtain multiple composite waveforms for use by the drive system of the motor.

10. The motor commutation waveform generation circuit as described in claim 9, characterized in that, The multiplexer of the signal combining circuit takes in the sensing signal from the motor to synchronize the multiple synthesized waveforms by arbitrarily laging the sensing signal from the motor.

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