Motor driver setting duty cycles based on temperature

Abstract

This invention discloses a motor driver that sets the duty cycle based on temperature. The motor driver senses the temperature of the environment in which the motor is located, sets a duty cycle modulation value based on the sensed temperature, and modulates a preset duty cycle according to this modulation value to form a start-up duty cycle. The motor driver sets or modulates the duty cycle of one or more waveforms of a start-up signal to be equal to the start-up duty cycle. The motor driver outputs a start-up signal to the motor.

Description

[Technical Field]

[0001] This invention relates to motor drives, and more particularly to a motor drive that sets the duty cycle based on temperature. [Previous Technology]

[0002] In electronic devices, fans are often used to cool processors and other heat-generating components. However, when a fan is placed in a low-temperature environment and a conventional motor driver attempts to start the fan motor at low temperatures, the motor becomes stuck due to the solidification of the lubricant between the bearings and balls, causing the conventional motor driver to fail to start the motor smoothly. [Summary of the Invention]

[0003] To address the shortcomings of existing technologies, the present invention provides a motor driver based on a temperature-set duty cycle. The motor driver based on a temperature-set duty cycle of the present invention includes a temperature sensor, a temperature duty cycle modulation circuit, a start-up duty cycle determination circuit, a start-up signal generation circuit, and a drive circuit. The temperature sensor is configured to sense a temperature of a motor or its surrounding environment as a sensed temperature, and output a temperature sensing signal. The temperature duty cycle modulation circuit is connected to the temperature sensor. The temperature duty cycle modulation circuit is configured to output a duty cycle modulation indication signal based on the temperature sensing signal. The start-up duty cycle determination circuit is connected to the temperature duty cycle modulation circuit. The start-up duty cycle determination circuit is configured to modulate a preset duty cycle according to the duty cycle modulation indication signal to form a start-up duty cycle, and output a start-up duty cycle indication signal based on the start-up duty cycle. The start-up signal generation circuit is connected to the start-up duty cycle determination circuit. The start signal generating circuit is configured to set or modulate the duty cycle of one or more waveforms of a start signal to be equal to the start duty cycle, based on the start duty cycle indication signal. The drive circuit is connected to the start signal generating circuit. The drive circuit is configured to output a drive signal to the motor based on the start signal.

[0004] In addition, the present invention provides a motor driving method based on temperature-set duty cycle. The motor driving method based on temperature-set duty cycle of the present invention includes the following steps: sensing a temperature of a motor or its environment as a sense temperature, and outputting a temperature sensing signal; outputting a duty cycle modulation indication signal based on the temperature sensing signal; modulating a preset duty cycle based on the duty cycle modulation indication signal to form a start-up duty cycle; modulating a preset duty cycle based on the duty cycle modulation value to form a start-up duty cycle; outputting a start-up duty cycle indication signal based on the start-up duty cycle; setting or modulating the duty cycle of one or more of a plurality of waveforms of a start-up signal to be equal to the start-up duty cycle based on the start-up duty cycle indication signal; and outputting a drive signal to the motor based on the start-up signal.

[0005] As described above, the present invention provides a motor driver that sets the duty cycle based on temperature. The motor driver of the present invention can adjust the drive signal output to the motor based on temperature, thereby modulating the thrust borne by the motor. In particular, when the lubricant between the bearings and balls of the motor solidifies and becomes viscous at low temperatures, it can increase the thrust borne by the motor to smoothly start and drive the motor.

[0006] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention.

Implementation Method

[0018] The following describes the implementation of the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the accompanying drawings of the present invention are only simple illustrations and are not depictions based on actual dimensions, as stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of protection of the present invention. In addition, the term "or" used herein should be interpreted as potentially including any combination of one or more of the associated listed items, depending on the actual situation.

[0019] Please refer to Figures 1 and 2, wherein Figure 1 is a block diagram of a motor driver based on temperature-set duty cycle according to the first embodiment of the present invention, and Figure 2 is a flowchart of the steps of the motor driving method based on temperature-set duty cycle according to the first embodiment of the present invention.

[0020] The motor drive method based on temperature-set duty cycle of the present invention may include steps S101 to S106 as shown in FIG2, which may be executed by the motor driver based on temperature-set duty cycle of the present invention as shown in FIG1 or FIG4.

[0021] In the first embodiment, the motor driver based on temperature-set duty cycle of the present invention includes a temperature sensor TSE, a temperature duty cycle modulation circuit TDY, a start duty cycle determination circuit SDT, a start signal generation circuit STA, and a drive circuit DRV, as shown in FIG1.

[0022] The temperature sensor TSE, temperature duty cycle modulation circuit TDY, start duty cycle determination circuit SDT, start signal generation circuit STA, and drive circuit DRV described herein each include one or more hardware components. For example, but not limited to, the temperature sensor TSE includes a thermistor, thermocouple, or other hardware components with temperature sensing function. The temperature duty cycle modulation circuit TDY, start duty cycle determination circuit SDT, and start signal generation circuit STA may include, for example, but not limited to, a processor or other hardware components with the same function. The drive circuit DRV may include, for example, but not limited to, multiple upper bridge switches and multiple lower bridge switches. The first terminals of the multiple upper bridge switches are coupled to a common voltage, and the second terminals of the multiple upper bridge switches are respectively connected to the first terminals of the multiple lower bridge switches. The drive circuit DRV is connected to the control terminal of each of the multiple upper bridge switches and the multiple lower bridge switches.

[0023] As shown in Figure 1, the temperature duty cycle modulation circuit TDY is connected to the temperature sensor TSE and the start-up duty cycle determination circuit SDT. The start-up signal generation circuit STA is connected to the start-up duty cycle determination circuit SDT and the drive circuit DRV. The drive circuit DRV is connected to the motor MT. The motor MT described herein can be a single-phase motor or a three-phase motor.

[0024] The temperature sensor TSE senses the temperature of the motor MT or the environment in which the motor MT is located as a sense temperature (step S101 in Figure 2), and outputs a temperature sensing signal TEMP based on this sense temperature.

[0025] The temperature duty cycle modulation circuit TDY acquires a sensed temperature indicated by a temperature sensing signal TEMP received from the temperature sensor TSE, and outputs a duty cycle modulation indication signal MUDUY based on this sensed temperature. For example, the temperature duty cycle modulation circuit TDY can calculate a temperature difference between this sensed temperature and a temperature threshold value (step S102 in FIG2), set a duty cycle modulation value corresponding to this temperature difference (step S103 in FIG2), and output a duty cycle modulation indication signal MUDUY based on this duty cycle modulation value. In this way, the duty cycle modulation amount is set according to the amount of temperature change.

[0026] The start duty cycle determination circuit SDT modulates a preset duty cycle based on a duty cycle modulation value indicated by a duty cycle modulation indication signal MUDUY received from the temperature duty cycle modulation circuit TDY, to form a start duty cycle (step S104 in Figure 2), and then outputs a start duty cycle indication signal STADUTY based on this start duty cycle.

[0027] The start signal generating circuit STA sets or modulates the duty cycle of one or more of the multiple waveforms of a start signal to be equal to a start duty cycle based on a start duty cycle indicated by a start duty cycle indication signal STADUTY received from the start duty cycle determining circuit SDT (step S105 in Figure 2).

[0028] The drive circuit DRV outputs a drive signal to the motor MT based on a start signal received from the start signal generation circuit STA, so as to start the motor MT and drive the motor MT to run after start-up (step S106 in FIG2).

[0029] In other words, the motor driver of the present invention adjusts the drive on the motor MT according to the temperature of the motor MT or the environment in which the motor MT is located, so that the thrust on the motor MT changes with the temperature of the motor MT or the environment in which the motor MT is located, so that the motor driver of the present invention can smoothly drive the motor MT with appropriate thrust to maintain its desired operation regardless of temperature changes. In particular, when the ambient temperature drops to an excessively low value, causing the lubricant between the bearings and balls of the motor to solidify and become sticky, the motor driver of the present invention can still smoothly start the motor.

[0030] Please refer to Figure 3, which is a flowchart of the steps of adjusting the duty cycle of the drive signal used to start the motor in a low-temperature environment in the motor drive method based on temperature setting duty cycle according to the second embodiment of the present invention.

[0031] The motor drive method based on temperature-set duty cycle of the present invention may further include steps S201 to S202 as shown in FIG3, which can be executed by the motor driver based on temperature-set duty cycle of the present invention as shown in FIG1 or FIG4.

[0032] After the temperature sensor TSE senses the temperature of the motor MT or the environment in which the motor MT is located as a sensed temperature (step S101 in FIG2), the temperature duty cycle modulation circuit TDY determines whether this sensed temperature is lower than a temperature threshold value (step S201 in FIG3) and outputs a duty cycle modulation indication signal MUDUY.

[0033] If the sensed temperature of the motor MT or the environment in which the motor MT is located is not lower than a temperature threshold value, the temperature duty cycle modulation circuit TDY does not calculate a temperature difference between this sensed temperature and the temperature threshold value (i.e., it does not execute step S102 of Figure 2), and does not further set and output a duty cycle modulation value corresponding to this temperature difference (or in practice, outputs a duty cycle modulation value of zero). When the start duty cycle determination circuit SDT does not receive a duty cycle modulation value (or in practice receives a duty cycle modulation value of zero), it does not increase a preset duty cycle (i.e., it does not execute step S103 of Figure 2). At this time, the temperature sensor TSE can continuously sense the temperature of the motor MT or the environment in which the motor MT is located (step S101 of Figures 2 and 3).

[0034] Conversely, if the sensing temperature of the motor MT or the environment in which the motor MT is located is lower than a temperature threshold value, the start duty cycle determination circuit SDT adjusts the duty cycle by a preset duty cycle based on a non-zero duty cycle modulation value indicated by a duty cycle modulation indication signal MUDUY received from the temperature duty cycle modulation circuit TDY. The adjusted preset duty cycle is used as a start duty cycle (step S202 in Figure 2).

[0035] After the start duty cycle determination circuit SDT sets a start duty cycle (step S202 in FIG2), the start signal generation circuit STA sets or modulates the duty cycle of one or more of the multiple waveforms of a start signal to be equal to a start duty cycle (step S105 in FIG2 and FIG3). Then, the drive circuit DRV outputs a drive signal to the motor MT according to this start signal to start the motor MT and drive the motor MT to run after starting (step S106 in FIG2 and FIG3).

[0036] When the ambient temperature of the motor MT is too low (such as below the above-mentioned temperature threshold), the solidification of the lubricant between the bearings and balls of the motor MT will cause the multiple mechanical components to stick together and fail to operate normally. At this time, the motor driving method of the present invention increases the thrust on the motor MT so as to smoothly push the motor MT.

[0037] Please refer to Figure 4, which is a block diagram of a motor driver based on temperature-set duty cycle according to the third embodiment of the present invention.

[0038] In the third embodiment, the motor driver based on temperature-set duty cycle of the present invention, as shown in FIG4, includes a temperature sensor TSE, a temperature duty cycle modulation circuit TDY, a start duty cycle determination circuit SDT, a start signal generation circuit STA, and a drive circuit DRV, and further includes a waveform pattern generation circuit PAN and an oscillation signal generation circuit OSC.

[0039] As shown in Figure 4, the temperature duty cycle modulation circuit TDY is connected to the temperature sensor TSE and the start-up duty cycle determination circuit SDT. The start-up signal generation circuit STA is connected to the start-up duty cycle determination circuit SDT, the waveform generation circuit PAN, and the drive circuit DRV. The drive circuit DRV is connected to the oscillation signal generation circuit OSC and the motor MT.

[0040] The temperature duty cycle modulation circuit TDY can set multiple corresponding duty cycle modulation values ​​based on the temperature difference between the temperature of the motor MT or its environment and a temperature threshold value sensed by the temperature sensor TSE, and output a duty cycle modulation indication signal MUDUY.

[0041] For example, the plurality of duty cycle modulation values ​​indicated in the duty cycle modulation indication signal MUDUY may include an initial duty cycle modulation value, a final duty cycle modulation value, or both.

[0042] Next, the start-up duty cycle determination circuit SDT can modulate an initial duty cycle INTDUTY based on an initial duty cycle modulation value indicated by a duty cycle modulation indication signal MUDUY received from the temperature duty cycle modulation circuit TDY, to form an initial start-up duty cycle. Alternatively, the start-up duty cycle determination circuit SDT can modulate a final duty cycle FNLDUTY based on a final duty cycle modulation value indicated by this duty cycle modulation indication signal MUDUY, to form a final start-up duty cycle.

[0043] The duty cycle of the earliest or a number of earlier waveforms of a start duty cycle indicator signal STADUTY generated by the start duty cycle determination circuit SDT is equal to an initial start duty cycle, and / or the duty cycle of the last or a number of later waveforms of the start duty cycle indicator signal STADUTY is equal to a final start duty cycle.

[0044] The start signal generating circuit STA can set the duty cycle of other waveforms in a start duty cycle indicator signal STADUTY based on an initial start duty cycle and a final start duty cycle. The duty cycles of these other waveforms are between an initial start duty cycle and a final start duty cycle.

[0045] The waveform pattern generation circuit PAN can store multiple reference pattern waveform signals.

[0046] The start signal generation circuit STA modulates multiple waveforms of multiple reference pattern waveform signals obtained from the waveform pattern generation circuit PAN based on multiple waveforms of a start duty cycle indication signal STADUTY received from the start duty cycle determination circuit SDT, so as to output multiple start signals.

[0047] The drive circuit DRV uses the voltage levels of multiple waveforms of multiple start signals received from the start signal generation circuit STA and the voltage levels of multiple waveforms of an oscillation signal received from the oscillation signal generation circuit OSC to determine the duty cycle of multiple waveforms of a drive signal.

[0048] The drive circuit DRV outputs a drive signal to the motor MT to start the motor MT and drive the motor MT to run after starting.

[0049] Please refer to Figure 5, which is a schematic diagram of the initial duty cycle of the drive signal output by the motor driver based on the temperature-set duty cycle according to the fourth embodiment of the present invention as a function of time.

[0050] The duty cycle determining circuit SDT can be started as shown in Figure 5, which can adjust an initial duty cycle INTDUTY from the first initial ratio INDUTY10 to the second initial ratio INDUTY11.

[0051] Please refer to Figure 6, which is a schematic diagram of the initial duty cycle and the final duty cycle of the drive signal output by the motor driver based on the temperature-set duty cycle according to the fifth embodiment of the present invention as a function of time.

[0052] The start-up duty cycle determining circuit SDT can, as shown in Figure 6, adjust an initial duty cycle INTDUTY from the first initial ratio INDUTY20 to the second initial ratio INDUTY21, and adjust a final duty cycle FNLDUTY from the first final ratio FNDUTY20 to the second final ratio FNDUTY21.

[0053] Please refer to Figure 7, which is a schematic diagram of a motor driver based on temperature-based duty cycle of the sixth embodiment of the present invention, which sets multiple duty cycles to correspond to multiple temperatures respectively.

[0054] As shown in Figure 1 or Figure 4, the temperature duty cycle modulation circuit TDY can set multiple reference modulation temperatures and their corresponding multiple reference modulation duty cycles. For example, as shown in Figure 7, there are multiple reference modulation temperatures TM1, TM2, TM3 and their corresponding multiple reference modulation duty cycles DTY1, DTY2, DTY3. Different reference modulation temperatures can correspond to different reference modulation duty cycles. Generally, the lower the temperature, the more severe the viscosity, and a larger reference modulation duty cycle is needed to increase the starting thrust of the motor MT.

[0055] After the temperature duty cycle modulation circuit TDY obtains a sensed temperature of the motor MT or its environment from the temperature sensor TSE, as shown in Figure 1 or Figure 4, the temperature duty cycle modulation circuit TDY calculates a temperature difference between the sensed temperature indicated by the temperature sensing signal TEMP and a temperature threshold value. Then, the temperature duty cycle modulation circuit TDY compares this sensed temperature with multiple reference modulation temperatures to determine a reference modulation duty cycle corresponding to a reference modulation temperature with the same temperature difference, and outputs a duty cycle modulation indication signal MUDUY indicating a reference modulation duty cycle to the start duty cycle determination circuit SDT.

[0056] If necessary, the temperature duty cycle modulation circuit TDY can establish a graph based on multiple set reference modulation temperatures and their corresponding reference modulation duty cycles, and construct a curve in this graph. The temperature duty cycle modulation circuit TDY can use this curve to find a reference modulation temperature that has the same temperature difference between the sensed temperature and a temperature threshold value as a reference modulation duty cycle value, and output a duty cycle modulation indication signal MUDUY indicating this duty cycle modulation value.

[0057] Next, the start duty cycle determination circuit SDT modulates a preset duty cycle according to a duty cycle modulation value indicated by a duty cycle modulation indication signal MUDUY to form a start duty cycle, and then outputs a start duty cycle indication signal STADUTY according to this start duty cycle.

[0058] Next, the start signal generating circuit STA sets or modulates the duty cycle of one or more of the multiple waveforms of a start signal to be equal to a start duty cycle according to a start duty cycle indicated by a start duty cycle indication signal STADUTY.

[0059] Finally, the drive circuit DRV outputs a drive signal to the motor MT based on this start signal, so as to start the motor MT and drive the motor MT to run after start (step S106 in Figure 2).

[0060] Please refer to Figures 8 and 9, wherein Figure 8 is a waveform diagram of the reference pattern waveform signal of the motor driver based on temperature setting duty cycle according to the seventh embodiment of the present invention, and Figure 9 is a waveform diagram of the reference pattern waveform signal, oscillation signal and drive signal of the motor driver based on temperature setting duty cycle according to the seventh embodiment of the present invention.

[0061] For example, the multiple reference pattern waveform signals output by the waveform pattern generating circuit PAN shown in Figure 4 may be the same as the multiple reference pattern waveform signals PUS, PVS, and PWS shown in Figure 8, and may include multiple third harmonic waveforms, or in practice may include multiple sine wave waveforms.

[0062] The start signal generating circuit STA can modulate multiple reference pattern waveform signals PUS, PVS, and PWS based on a start duty cycle indication signal STADUTY received from the start duty cycle determining circuit SDT, thereby forming multiple start signals STUS, STVS, and STWS as shown in Figure 8.

[0063] For example, the oscillation signal received by the drive circuit DRV from the oscillation signal generation circuit OSC may be the same as the oscillation signal OLS shown in Figure 9, which includes multiple triangular wave waveforms, or in practice may include multiple sawtooth wave waveforms.

[0064] The drive circuit DRV can compare the voltages of multiple waveforms of multiple start signals STUS, STVS, and STWS with the voltages of multiple waveforms of multiple oscillation signals OLS to determine the duty cycle of multiple waveforms of multiple drive signals DRUS, DRVS, and DRWS output to the motor MT.

[0065] Please refer to Figures 10 and 11, wherein Figure 10 is a waveform diagram of the signal of the motor driver based on temperature-set duty cycle according to the eighth embodiment of the present invention at room temperature, and Figure 11 is a waveform diagram of the signal of the motor driver based on temperature-set duty cycle according to the eighth embodiment of the present invention at low temperature.

[0066] As shown in Figures 10 and 11, a detection indication signal DES at a high level for a certain period of time can be used as a sensing time. As shown in Figure 1 or Figure 4, the temperature sensor TSE of the motor driver of the present invention can sense the temperature of the motor MT or its environment during this sensing time.

[0067] At room temperature, as shown in Figure 1 or Figure 4, the drive circuit DRV of the motor driver of the present invention outputs a drive signal DTS0 as shown in Figure 10 to the motor MT, so as to drive the motor MT to run at a speed of a motor speed signal RPM, and cause the motor MT to generate a motor current signal IMTS0 as shown in Figure 10.

[0068] At low temperatures, the drive circuit DRV of the motor driver of the present invention, as shown in Figure 1 or Figure 4, outputs a drive signal DTS1 as shown in Figure 11 to the motor MT, so as to drive the motor MT to run at a speed of a motor speed signal RPM, and cause the motor MT to generate a motor current signal IMTS1 as shown in Figure 10.

[0069] It is worth noting that the motor MT is more difficult to drive at low temperatures than at normal temperatures. For example, the lubricating oil may solidify at low temperatures, causing multiple mechanical components of the motor to stick together and making it difficult to drive. Therefore, the duty cycle of multiple waveforms of a drive signal DTS1 output to the motor MT at low temperatures is higher than the duty cycle of multiple waveforms of a drive signal DTS0 output to the motor MT at normal temperatures.

[0070] At low temperatures, the drive circuit DRV of the motor driver of the present invention increases the duty cycle of a drive signal DTS1, thereby increasing the current value of a motor current signal IMTS1 of the motor MT, thus increasing the thrust on the motor MT, so that the motor MT can still start smoothly at low temperatures, and the operating speed at low temperatures can be the same as the operating speed at normal temperatures.

[0071] In summary, the present invention provides a motor driver that sets the duty cycle based on temperature. The motor driver of the present invention can adjust the drive signal output to the motor based on temperature, thereby modulating the thrust borne by the motor. In particular, when the lubricant between the bearings and balls of the motor solidifies and becomes viscous at low temperatures, it can increase the thrust borne by the motor to smoothly start and drive the motor.

[0072] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention specification and drawings are included in the scope of the patent application of the present invention. [Simplified Explanation of the Diagram]

[0007] Figure 1 is a block diagram of a motor driver based on temperature-set duty cycle according to the first embodiment of the present invention.

[0008] Figure 2 is a flowchart of the steps of the motor driving method based on temperature setting duty cycle according to the first embodiment of the present invention.

[0009] Figure 3 is a flowchart of the steps of adjusting the duty cycle of the drive signal used to start the motor in a low-temperature environment in the motor drive method based on temperature setting duty cycle according to the second embodiment of the present invention.

[0010] Figure 4 is a block diagram of a motor driver based on temperature-set duty cycle according to the third embodiment of the present invention.

[0011] Figure 5 is a schematic diagram of the initial duty cycle of the drive signal output by the motor driver based on temperature-set duty cycle according to the fourth embodiment of the present invention as a function of time.

[0012] Figure 6 is a schematic diagram of the initial duty cycle and the final duty cycle of the drive signal output by the motor driver based on the temperature-set duty cycle according to the fifth embodiment of the present invention as a function of time.

[0013] Figure 7 is a schematic diagram of a motor driver based on temperature-based duty cycle of the sixth embodiment of the present invention, which sets multiple duty cycles to correspond to multiple temperatures respectively.

[0014] Figure 8 is a waveform diagram of the reference pattern waveform signal of the motor driver based on temperature setting duty cycle according to the seventh embodiment of the present invention.

[0015] Figure 9 is a waveform diagram of the reference pattern waveform signal, oscillation signal and drive signal of the motor driver based on temperature setting duty cycle according to the seventh embodiment of the present invention.

[0016] Figure 10 is a waveform diagram of the signal of the motor driver based on temperature-set duty cycle according to the eighth embodiment of the present invention at room temperature.

[0017] Figure 11 is a waveform diagram of the signal of the motor driver based on temperature-set duty cycle according to the eighth embodiment of the present invention at low temperature.

Claims

1. A motor driver with a temperature-based duty cycle setting, comprising: a temperature sensor configured to sense a temperature of a motor or its environment as a sense temperature, and to output a temperature sensing signal; and a temperature duty cycle modulation circuit connected to the temperature sensor, configured to output a duty cycle modulation indication signal based on the temperature sensing signal. A start duty cycle determining circuit is connected to the temperature duty cycle modulation circuit and configured to modulate a preset duty cycle according to the duty cycle modulation indication signal to form a start duty cycle, and output a start duty cycle indication signal according to the start duty cycle. A start signal generating circuit, connected to the start duty cycle determining circuit, is configured to set or modulate the duty cycle of one or more of a plurality of waveforms of a start signal to be equal to the start duty cycle, based on the start duty cycle indication signal. And a drive circuit connected to the start signal generation circuit, configured to output a drive signal to the motor according to the start signal; The temperature duty cycle modulation circuit is configured to set a plurality of reference modulation temperatures and a plurality of reference modulation duty cycles corresponding to each other, wherein the plurality of reference modulation duty cycles are different from each other; wherein the temperature duty cycle modulation circuit is configured to establish a graph based on the plurality of reference modulation temperatures and the plurality of reference modulation duty cycles, wherein the horizontal axis of the graph represents temperature and indicates the plurality of reference modulation temperatures, and the vertical axis of the graph represents duty cycle and indicates the plurality of reference modulation duty cycles; wherein the temperature duty cycle modulation circuit is configured to construct a curve in the graph, wherein the first of the plurality of portions of the curve falls between the first reference modulation temperature and the second reference modulation temperature, and this first portion of the curve remains aligned with the first reference modulation duty cycle in the graph and does not change with temperature. Wherein, the second of the plurality of portions of the curve falls between the second and third reference modulation temperatures, one end of the second portion of the curve aligns with the first reference modulation duty cycle and the other end aligns with the second reference modulation duty cycle in the curve graph, the second portion of the curve decreases linearly with increasing temperature, the second reference modulation temperature is greater than the first reference modulation temperature but less than the third reference modulation temperature; wherein the temperature duty cycle modulation circuit is configured to calculate a temperature difference between the sensed temperature indicated by the temperature sensing signal and a temperature threshold value; wherein the temperature duty cycle modulation circuit is configured to find, based on the curve of the curve graph, the reference modulation duty cycle corresponding to the reference modulation temperature with the same temperature difference as a duty cycle modulation value, and output a duty cycle modulation indication signal indicating the duty cycle modulation value to the start duty cycle determination circuit.

2. The motor driver with a temperature-based duty cycle as described in claim 1, wherein, When the sensed temperature is lower than the temperature threshold, the start-up duty cycle determination circuit increases the preset duty cycle according to the duty cycle modulation indication signal to form the start-up duty cycle.

3. The motor driver with a temperature-based duty cycle as described in claim 2, wherein, When the sensed temperature is not lower than the temperature threshold value, the start-up duty cycle determination circuit does not increase the preset duty cycle according to the duty cycle modulation indication signal, and directly uses the preset duty cycle as the start-up duty cycle.

4. The motor driver based on temperature-set duty cycle as described in claim 1, wherein the start-up duty cycle determining circuit modulates an initial duty cycle according to the duty cycle modulation indication signal to form an initial start-up duty cycle, and the duty cycle of the earliest or a plurality of the waveforms of the start-up signal output by the start-up signal generating circuit is equal to the initial start-up duty cycle.

5. The motor driver based on temperature-set duty cycle as claimed in claim 1, wherein the start duty cycle determining circuit modulates a final duty cycle according to the duty cycle modulation indication signal to form a final start duty cycle, and the duty cycle of the last or later of the plurality of waveforms of the start signal output by the start signal generating circuit is equal to the final start duty cycle.

6. The motor driver based on temperature-set duty cycle as described in claim 1 further comprises: a waveform generation circuit connected to the start signal generation circuit, wherein the start signal generation circuit modulates a plurality of reference waveform signals obtained from the waveform generation circuit according to the start duty cycle indication signal, and outputs the start signal according to the modulated plurality of reference waveform signals.

7. The temperature-based duty cycle motor driver as claimed in claim 1 further comprises: an oscillation signal generating circuit connected to the drive circuit and configured to output an oscillation signal, wherein the drive circuit compares the voltage level of the oscillation signal with the voltage level of the start signal to determine the duty cycle of a plurality of waveforms of the drive signal.

8. A motor driving method based on temperature-based duty cycle setting, comprising the following steps: setting multiple reference modulation temperatures and their corresponding multiple reference modulation duty cycles, wherein, The multiple reference modulation duty cycles are different from each other; a graph is established based on the multiple reference modulation temperatures and their corresponding multiple reference modulation duty cycles, wherein the horizontal axis of the graph represents temperature and indicates the multiple reference modulation temperatures, and the vertical axis of the graph represents duty cycle and indicates the multiple reference modulation duty cycles; a curve is constructed in the graph, wherein the first of the multiple portions of the curve falls between the first and second reference modulation temperatures, and this first portion of the curve remains aligned with the first reference modulation duty cycle in the graph and does not change with temperature, while the second of the multiple portions of the curve falls between the second and third reference modulation temperatures, one end of this second portion of the curve is aligned with the first reference modulation duty cycle in the graph and the other end is aligned with the second reference modulation duty cycle, and the second portion of the curve decreases linearly with increasing temperature, and the second reference modulation temperature is greater than the first reference modulation temperature but less than the third reference modulation temperature; Sensing a temperature of a motor or its surrounding environment as a sensing temperature to generate a temperature sensing signal; calculating a temperature difference between the sensing temperature indicated by the temperature sensing signal and a temperature threshold value. Based on the curve of the graph, find the reference modulation duty cycle corresponding to the reference modulation temperature that has the same temperature difference as the reference modulation temperature as a duty cycle modulation value, and output a duty cycle modulation indication signal indicating the duty cycle modulation value. Based on the duty cycle modulation indication signal, a preset duty cycle is modulated to form a start duty cycle; Based on the duty cycle modulation value, a preset duty cycle is modulated to form a start-up duty cycle; Based on the stated start duty cycle, output a start duty cycle indication signal; Based on the start duty cycle indication signal, the duty cycle of one or more of a plurality of waveforms of a start signal is set or modulated to be equal to the start duty cycle; and based on the start signal, a drive signal is output to the motor.

9. The motor drive method based on temperature-set duty cycle as described in claim 8 further includes the following steps: when the sensed temperature is lower than the temperature threshold value, the preset duty cycle is increased according to the duty cycle modulation indication signal to form the start-up duty cycle.

10. The motor drive method based on temperature-set duty cycle as described in claim 8 further includes the following steps: When the sensed temperature is not lower than the temperature threshold value, according to the duty cycle modulation indication signal, the preset duty cycle is not increased, and the preset duty cycle is directly used as the start-up duty cycle.

11. The motor drive method based on temperature-set duty cycle as described in claim 8 further comprises the following steps: modulating an initial duty cycle according to the duty cycle modulation indication signal to form an initial start-up duty cycle; and setting the duty cycle of the earliest or a plurality of the waveforms of the start-up signal equal to the initial start-up duty cycle.

12. The motor drive method based on temperature-set duty cycle as described in claim 8 further comprises the following steps: modulating a final duty cycle according to the duty cycle modulation indication signal to form a final start duty cycle; setting the duty cycle of the last generated or the later generated of the plurality of waveforms of the start signal to be equal to the final start duty cycle.

13. The motor drive method based on temperature-set duty cycle as described in claim 8 further includes the following steps: modulating multiple reference pattern waveform signals according to the start-up duty cycle to output the start-up signal.

14. The motor drive method for setting the duty cycle based on temperature as described in claim 8 further includes the following steps: comparing the voltage level of an oscillation signal with the voltage level of the start signal to determine the duty cycle of a plurality of waveforms of the drive signal.

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