Electronic system with heat dissipation and feedforward active noise control function

Abstract

The electronic system comprises a fan module, an embedded controller, an error microphone, an active noise reduction controller, and a speaker module. The error microphone captures noise generated by the electronic system in operation and outputs a corresponding error signal. The active noise reduction controller calculates a narrow-band noise of a relevant actual single-blade fundamental frequency noise or an actual BPF fundamental frequency noise and a corresponding phase difference in the noise generated by the fan module in actual operation based on the error signal and fan information provided by the embedded controller, and drives the speaker module to provide an anti-phase noise signal accordingly. The value of the error signal is adjusted to 0 by adaptively adjusting the anti-phase noise signal to cancel the noise generated by the electronic system in operation, thereby simultaneously providing heat dissipation and noise reduction functions.

Description

Technical Field

[0001] The present invention provides an electronic system with heat dissipation and feedforward active noise control functions, and more particularly an electronic system with heat dissipation and feedforward active narrowband noise control functions. Background Technology

[0002] In today's information society, computer systems have become an indispensable information tool for most people. To prevent components from overheating and causing power reduction or damage, computer systems generally use fans to provide cooling, either to expel heat generated inside the device or to draw in cool air from outside.

[0003] The fan's speed and static pressure determine its airflow. The noise level of a fan is roughly proportional to the fifth root of its speed; the faster the speed, the stronger the heat dissipation, but the louder the noise. As central processing units become more powerful, the waste heat generated inside the device also increases. In addition, the trend of miniaturization reduces heat flow efficiency. How to balance heat dissipation and noise reduction is an important issue. Summary of the Invention

[0004] This invention provides an electronic system with heat dissipation and feedforward active noise control functions, comprising a fan module, an embedded controller, an error microphone, an active noise cancellation controller, and a speaker module. The fan module operates according to a fan control signal to provide heat dissipation. The embedded controller provides the fan control signal and a synchronization signal, wherein the synchronization signal contains information about the structure and operational settings of the fan module. The error microphone detects noise generated during the operation of the electronic system to provide a corresponding error signal. The active noise cancellation controller calculates an actual single-blade fundamental frequency, an actual blade passage frequency fundamental frequency, an actual blade passage frequency multiple, and a phase shift for the fan module at each operating speed; provides a phase compensation signal based on the synchronization signal, wherein the phase compensation signal contains the actual single-blade fundamental frequency, the actual blade passage frequency fundamental frequency, the actual blade passage frequency multiple, and the phase shift for the fan module operating at a current speed; and generates a speaker control signal based on the error signal and the phase compensation signal. The loudspeaker module is used to generate an anti-phase noise signal based on the loudspeaker control signal. The anti-phase noise signal includes at least a first noise cancellation waveform and a second noise cancellation waveform. The first noise cancellation waveform is the inverse signal of the fundamental frequency of the actual single blade, and the second noise cancellation waveform is the inverse signal of the fundamental frequency of the actual blade passage frequency. Attached Figure Description

[0005] Figure 1 This is a functional block diagram of an electronic system with heat dissipation and feedforward active noise control functions according to an embodiment of the present invention.

[0006] Figure 2 This is a schematic diagram illustrating the implementation of the active noise cancellation controller in an embodiment of the present invention.

[0007] Figure 3 This is a flowchart illustrating the operation of the electronic system in offline mode according to an embodiment of the present invention.

[0008] Figure 4 This is a flowchart illustrating the operation of the electronic system in online mode according to an embodiment of the present invention.

[0009] in:

[0010] 10: Processor;

[0011] 20: Fan module;

[0012] 30: Embedded controller;

[0013] 40: Speaker module;

[0014] 50: Error microphone;

[0015] 60: Active noise cancellation controller;

[0016] 62: Frequency calculator;

[0017] 64: Signal generator;

[0018] 66: Digital filter;

[0019] 68: Speaker driver circuit;

[0020] 70: Secondary path compensation transfer function module;

[0021] 72: Secondary path transfer function module;

[0022] 74: Noise weighting and conversion module;

[0023] 76: Adaptive filter;

[0024] 100: Electronic systems;

[0025] 310-340, 410-450: Steps;

[0026] S FG Fan control signal;

[0027] S MIC Speaker control signal;

[0028] S SYN Synchronization signal;

[0029] x(n): Phase compensation signal;

[0030] x'(n): Correction phase compensation signal;

[0031] y(n): Inverted noise signal;

[0032] y'(n): Corrects inverting noise signals;

[0033] e(n): Error signal;

[0034] e'(n): Processed error signal;

[0035] d(n): Noise signal. Detailed Implementation

[0036] Figure 1 This is a functional block diagram of an electronic system 100 with heat dissipation and feedforward active noise control functions according to an embodiment of the present invention. The electronic system 100 includes a processor 10, a fan module 20, an embedded controller (EC) 30, a speaker module 40, an error microphone 50, and an active noise cancellation (ANC) controller 60.

[0037] The processor 10 may be a central processing unit (CPU) or a graphics processing unit (GPU). It is the key computing engine in the electronic system 100, responsible for executing the instructions and programs required by the operating system, and is also the main source of waste heat in the electronic system 100.

[0038] The fan module 20 may have different structures depending on its type, but it mainly uses a motor to drive the fan blades to rotate, drawing cooler air into the chassis and expelling hotter air from inside, thereby achieving a heat dissipation effect. In this invention, the fan module 20 will use a fan control signal S provided by the embedded controller 30. FG To operate, the fan control signal S FG The larger the value, the faster the motor speed in fan module 20, resulting in stronger heat dissipation, but also generating more noise. During the operation of electronic system 100, fan module 20 is typically the primary source of noise. In one embodiment, the fan control signal S... FGThe signal can be a square wave signal with pulse width modulation (PWM), which adjusts the motor speed in fan module 20 by changing its duty cycle. In one embodiment, fan module 20 may include one or more axial or centrifugal fans. However, the number of fans, fan type, and fan drive method included in fan module 20 do not limit the scope of this invention.

[0039] The embedded controller 30 stores the EC codes for various operations of the relevant electronic system 100 and the timing of important power-on signals. In the power-off state, the embedded controller 30 remains running, waiting for user power-on notifications; in the power-on state, the embedded controller 30 controls the system's standby / sleep state, keyboard controller, charging indicator light, and motor speed in the fan module 20. The embedded controller 30 typically includes a temperature sensor (not shown). Figure 1 This monitors the operating temperature of the processor 10 and outputs a fan control signal S accordingly. FG As the operating temperature of processor 10 increases, the fan control signal S... FG The longer the working cycle, the faster the motor speed in fan module 20; the lower the operating temperature of processor 10, the faster the fan control signal S... FG The shorter the working cycle, the slower the motor speed in fan module 20.

[0040] The loudspeaker module 40 is an electronic component that converts electronic signals into sound signals. It typically includes a diaphragm and a drive circuit consisting of an electromagnet and a voice coil. The loudspeaker module 40 can control the sound according to a loudspeaker control signal S provided by the ANC controller 60. MIC To operate, when the speaker control signal S MIC When current passes through the voice coil, the voice coil vibrates with the frequency of the current, and the diaphragm connected to the voice coil also vibrates, thereby pushing the surrounding air to vibrate and produce sound. In this embodiment of the invention, the diaphragm of the speaker module 40 is disposed within the air outlet structure of the fan module 20, and can be controlled according to the speaker control signal S. MIC This generates an inverted noise signal y(n).

[0041] Error microphone 50 is used to capture noise during the operation of electronic system 100 and output a corresponding error signal e(n) to ANC controller 60, where d(n) represents the noise signal to be eliminated during the operation of electronic system 100. Since fan module 20 is the main noise source, error microphone 50 can be placed near the air outlet of fan module 20. Error microphone 50 can detect noise through a main path and a secondary path: the main path is related to the signal transmission path between fan module 20 and error microphone 50, through which noise signal d(n) is captured; while the secondary path is related to the signal transmission path between speaker module 40 and error microphone 20, through which a corrected inverted noise signal y'(n) of the relevant inverted noise signal y(n) is captured. More specifically, the error signal e(n) output by error microphone 50 is the difference between noise signal d(n) and corrected inverted noise signal y'(n), and the smaller the value of error signal e(n), the better the noise reduction effect. In one embodiment, the error microphone 50 may be a digital microelectromechanical system (MEMS) microphone, which has high heat resistance, high vibration resistance, and high resistance to radio frequency interference. However, the type of error microphone 50 does not limit the scope of this invention.

[0042] The ANC controller 60 can receive a synchronization signal S from the embedded controller 30. SYN and receiving the error signal e(n) from the error microphone 50, wherein the synchronization signal S SYN This includes information on the structure of the relevant fan module 20 (e.g., the number of fan blades) and its operating settings (e.g., motor speed in different modes). Based on the synchronization signal S... SYN Based on the error signal e(n), the ANC controller 60 can calculate the narrowband noise in the noise generated by the fan module 20 during actual operation, and then provide the speaker control signal S accordingly. MIC The speaker module 40 is driven so that the anti-phase noise signal y(n) provided by the speaker module 40 can effectively cancel the noise signal d(n), that is, the error signal e(n) is reduced to 0 as much as possible.

[0043] Figure 2 This is a schematic diagram illustrating the implementation of the ANC controller 60 in an embodiment of the present invention. The ANC controller 60 includes a frequency calculator 62, a signal generator 64, a digital filter 66, a speaker driver circuit 68, a secondary path compensation transfer function module 70, a secondary path transfer function module 72, a noise weighting and conversion module 74, and an adaptive filter 76.

[0044] In this invention, the electronic system 100 can operate in an offline mode and an online mode, wherein the offline mode can determine information about the frequency phase shift at a specific motor speed, while the online mode can provide feedforward active noise control.

[0045] Figure 3 A flowchart of the electronic system 100 operating in offline mode is shown, which includes the following steps:

[0046] Step 310: The fan module 20 operates at a specific fan speed.

[0047] Step 320: Measure the noise frequency and corresponding power at a specific fan speed.

[0048] Step 330: Calculate the phase shift relationship of each noise frequency at a specific fan speed.

[0049] Step 340: Design a phase compensation signal x(n) for a specific fan speed.

[0050] The noise source of the fan module 20 during operation comes from the airflow caused by the motor rotation. The narrow-frequency components may originate from the thickness noise caused by the volume displacement generated by the fan blade movement, or from the blade passing frequency (BPF) noise caused by the variable load forces on the fan blade surface (including axial lift and fan surface tension). Since BPF and related harmonics are related to the pressure disturbance generated when each fan blade passes through a fixed reference point, specific narrow-frequency noise is generated when periodic pressure waves are generated at the fan blade tip. The frequency calculator 62 of the ANC controller 60 can use the synchronization signal S provided by the embedded controller 30... SYN The current rotational speed, estimated single-blade frequency, and number of blades of fan module 20 are known, where the BPF value is the product of the motor rotational speed and the number of blades of fan module 20. Assuming that fan module 20 has 37 blades, Table 1 below shows the data calculated by the frequency calculator 62, but does not limit the scope of this invention. The unit of motor rotational speed is rpm, and the unit of frequency is Hertz.

[0051] 500 8.3 16.6 24.9 33.2 37 307.1 614.2 921.3 1000 16.6 33.2 49.8 66.4 37 614.2 1228.4 1842.6 1500 25 50 75 100 37 925 1850 2775 2000 33.3 66.6 99.9 133.2 37 1232.1 2464.2 3696.3 2500 41.7 83.4 125.1 166.8 37 1542.9 3085.8 4628.7 3000 50 100 150 200 37 1850 3700 5550 3500 58.3 116.6 174.9 233.2 37 2157.1 4314.2 6471.3 4000 66.7 133.4 200.1 266.8 37 2467.9 4935.8 7403.7 4500 75 150 225 300 37 2775 5550 8325 5000 83.3 166.6 249.9 333.2 37 3082.1 6164.2 9246.3 5500 91.6 183.2 274.8 366.4 37 3389.2 6778.4 10167.6 5700 95 190 285 380 37 3515 7030 10545

[0052] Table 1

[0053] As mentioned above, the fan module 20 may have different speed settings, and the noise signals generated by different speeds may be phase-shifted due to the tolerance of the electronic system 100. Therefore, the present invention will first calculate the phase shift information of each speed of the relevant fan module 20 in offline mode.

[0054] After the fan module 20 operates at a specific speed in step 310, the actual noise frequency and corresponding power at that specific speed are measured in step 320. In one embodiment, step 320 may include operations such as sound signal segmentation, sound signal zero-padding, sound signal conversion, and sound signal peak determination. More specifically, when the electronic system 100 operates in offline mode, the error microphone 50 captures the noise signal generated by the fan module 20 at a specific fan speed, segments the captured noise signal into multiple segments (e.g., each segment contains 1024 sampling points), extends the length of each segment sequence (e.g., extends each segment length to 1024×8 sampling points), places the original 1024 sampling points of the noise signal at the beginning of each extended segment sequence, and then zero-padding the 1024×7 additional sampling points at the end of each segment sequence. Next, the present invention applies a Fast Fourier Transform (FFT) to each zero-padding sequence to convert the noise signal from the time domain into a power-frequency response in the frequency domain. Finally, the present invention determines the peak value in the frequency response to calculate the actual BPF fundamental frequency and actual BPF multipliers at this specific fan speed. The values ​​of the actual BPF fundamental frequency and actual BPF multipliers may differ from the theoretical values ​​shown in Table 1 by ±100Hz.

[0055] In step 330, the present invention calculates the phase shift relationship of each noise frequency at a specific fan speed. In one embodiment, since the signal processing of the BPF fundamental frequency affects the BPF harmonic signals, the speaker driver circuit 68 can control the speaker module 40 to sequentially play the BPF fundamental frequency signal, second harmonic signal, ..., Nth harmonic signal (N is an integer greater than 1) of the noise signal at a specific fan speed, until all harmonic signals at that specific fan speed have been processed.

[0056] The following describes the detailed implementation of step 330. The power of the audio signal is related to its frequency. First, a dynamic phase sine wave containing K sequence lengths is provided for the BPF fundamental frequency signal, with each sequence having a phase shift. for Therefore, the signal of the k-th sequence can be expressed as: Where K is an integer greater than 1, and k is an integer between 1 and K. That is, when the phase of the BPF fundamental frequency signal is fixed, the phase difference of each sequence in its sine wave is fixed (e.g., 40°, 60°, 80°…), while the phase difference of each sequence in the aforementioned dynamic phase sine wave increases. The degree changes (e.g., at K=12, the degrees are 40°, 90°, 140°... in sequence).

[0057] Next, the speaker driver circuit 68 controls the speaker module 40 to sequentially play dynamic phase sine waves at specific fan speeds. The error microphone 50 captures the signals and calculates the power of each sequence, then sets the phase of the sequence with the lowest power as the phase shift of the noise frequency. For example, for the dynamic phase sine wave of the relevant BPF fundamental frequency signal, if its second sequence... With the lowest power, the phase offset of the BPF baseband signal will be set to... For the dynamic phase sine wave of the relevant BPF second harmonic signal, if its k-th sequence With the lowest power, the phase offset of the BPF second harmonic signal will be set to...

[0058] Finally, in step 340, the present invention repeats steps 310-330 for each fan speed of the fan module 20 to design a corresponding phase compensation signal x(n) for each fan speed, wherein the fundamental frequency and harmonics of the BPF have different power and phase.

[0059] Figure 4 The flowchart shown illustrates the operation of electronic system 100 in online mode, which includes the following steps:

[0060] Step 410: Error microphone 50 captures noise and provides a corresponding error signal e(n).

[0061] Step 420: The ANC controller 60 receives the synchronization signal S from the embedded controller 30. SYN The number of fan blades in fan module 20 and the motor speed in each mode are obtained, and the corresponding phase compensation signal x(n) is provided.

[0062] Step 430: The ANC controller 60 calculates the actual single-blade fundamental frequency, actual harmonic frequency, and actual BPF of the fan module 20 during operation based on the error signal e(n) and the phase compensation signal x(n), and provides the speaker control signal S accordingly. MIC .

[0063] Step 440: The speaker module 40 operates according to the speaker control signal S MIC This generates an inverted noise signal y(n).

[0064] Step 450: The ANC controller 60 provides a corrected reference signal x'(n) for the secondary path correction reference signal x(n), and corrects the reverse noise signal y(n) to provide a corrected reverse noise signal y'(n); execute step 310.

[0065] In step 410, when the electronic system 100 is operating in online mode, the error microphone 50 captures noise and provides a corresponding error signal e(n). As mentioned earlier, the error signal e(n) provided by the error microphone 50 is the difference between the noise signal d(n) and the corrected inverted noise signal y'(n), and the noise signal d(n) mainly comes from the rotation of the fan blades when the fan module 20 is operating.

[0066] In step 420, the signal generator 64 of the ANC controller 60 provides a corresponding phase compensation signal x(n) based on the data calculated by the frequency calculator 62 and the data obtained in the offline mode. The phase compensation signal x(n) includes information such as the actual octave, actual BPF, phase shift, and sound pressure level spectrum (dBSPL) of the fan module 20 at the current speed, which can determine the speaker control signal S. MIC The reference power value is obtained, and the speaker control signal S can be changed by adjusting the parameter W(Z) of the digital filter 66. MIC The power value.

[0067] In steps 430 and 440, the digital filter 66 of the ANC controller 60 drives the speaker driver circuit 68 to output the speaker control signal S based on the error signal e(n) and the phase compensation signal x(n). MIC This drives the speaker module 40 to provide an anti-phase noise signal y(n), where W(Z) represents the adjustable operating parameters of the digital filter 66.

[0068] The inherent characteristics of the speaker module 40 and the white noise it sends to the fan module 20 during operation affect the secondary path between the speaker module 40 and the error microphone 50. Assuming the inverted noise signal y(n) currently provided by the speaker module 40 can completely cancel the noise signal d(n), after transmission via the secondary path, the inverted noise signal y(n) captured by the error microphone 50 may not be able to completely cancel the noise signal d(n) due to signal attenuation or distortion. Therefore, in step 450, the secondary path compensation transfer function module 70 of the ANC controller 60 can obtain the estimated signal of the secondary path from the embedded controller 30. Then based on the predicted signal The reference signal x(n) is corrected to provide the corrected reference signal x'(n). The secondary path transfer function module 72 of the ANC controller 60 can be a spectrum analyzer to measure the actual frequency response S(Z) of the secondary path, and then correct the inverse noise signal y(n) accordingly to provide the corrected inverse noise signal y'(n), thereby compensating for the impact of the secondary path on signal transmission.

[0069] The noise weighting conversion module 74 is coupled to the error microphone 50 and processes the error signal e(n) measured by the error microphone 50 according to a specific signal weighting and signal conversion method. The processed error signal e'(n) is then transmitted to the adaptive filter 76. In one embodiment, the noise weighting conversion module 74 may use A-weighting and Fast Fourier Transform (FFT) to process the error signal e(n). However, the signal weighting and signal conversion methods used by the noise weighting conversion module 74 do not limit the scope of this invention.

[0070] The adaptive filter 76 is coupled to the secondary path compensation transfer function module 70 and the noise weighting conversion module 74. It processes the corrected phase compensation signal x'(n) and the processed error signal e'(n) according to a specific algorithm, thereby adjusting the parameters W(Z) of the digital filter 66. More specifically, the corrected phase compensation signal x'(n) includes information such as the actual motor speed of the fan module 20, the actual single-blade fundamental frequency, the actual harmonics, the actual BPF, and the phase shift. The adaptive filter 76 then uses the processed error signal e'(n) to calculate the corrected actual single-blade fundamental frequency, the corrected actual harmonics, and the corrected actual BPF, among other related narrowband noise information, during the operation of the fan module 20, and adjusts the parameters W(Z) of the digital filter 66 accordingly. In this way, when the digital filter 66 drives the speaker drive circuit 68 to output the speaker control signal S... MIC At that time, the inverted noise signal y(n) generated by the speaker module 40 will reflect the actual operating status of the fan module 20 and the current noise reduction level. More specifically, the inverted noise signal y(n) includes at least a first noise cancellation waveform and a second noise cancellation waveform, wherein the first noise cancellation waveform is an inverted signal related to the actual single blade fundamental frequency, and the second noise cancellation waveform is an inverted signal related to the actual BPF fundamental frequency.

[0071] In one embodiment, the adaptive filter 76 may process the corrected phase compensation signal x'(n) and the processed error signal e'(n) according to the least mean square (LMS) algorithm. However, the algorithm used by the adaptive filter 76 does not limit the scope of the present invention.

[0072] In summary, the electronic system 100 of this invention first calculates the phase shift information of the relevant fan module 20 at each rotational speed in offline mode. Then, when operating in online mode, the error microphone 50 captures noise and outputs a corresponding error signal. The ANC controller 60 calculates the narrowband noise (actual single-blade fundamental frequency noise or actual BPF fundamental frequency noise) in the noise generated by the fan module 20 during actual operation based on the error signal and the fan information provided by the embedded controller 30. Based on this, it drives the speaker module 40 to provide an inverse noise signal y(n), so that the inverse noise signal y(n) can cancel the noise generated by the electronic system 100 during operation. By adaptively adjusting the inverse noise signal to bring the error signal value to 0, this invention addresses the important issues of heat dissipation and noise reduction, and can compensate for the phase shift caused by system tolerances to improve the accuracy of active noise control.

[0073] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made in accordance with the claims of the present invention should be included within the scope of the present invention.

Claims

1. An electronic system with heat dissipation and feedforward active noise control functions, comprising: A fan module is used to operate according to a fan control signal to provide heat dissipation. An embedded controller is used to provide the fan control signal and a synchronization signal, wherein the synchronization signal contains information on the structure and operation settings of the fan module; An error microphone is used to detect noise generated during the operation of the electronic system in order to provide a corresponding error signal; An active noise cancellation controller is used to: Find the actual single-blade fundamental frequency, the actual blade passing frequency fundamental frequency, the actual BPF harmonic frequency, and the phase offset of the fan module at each speed. A phase compensation signal is provided based on the synchronization signal, wherein the phase compensation signal includes the actual single-blade fundamental frequency, the actual blade passage frequency fundamental frequency, the actual BPF harmonic frequency, and the phase offset when the fan module is operating at a current speed; and A loudspeaker control signal is generated based on the error signal and the phase compensation signal; and A loudspeaker module is used to generate an anti-phase noise signal based on the loudspeaker control signal, wherein the anti-phase noise signal includes at least a first noise cancellation waveform and a second noise cancellation waveform, the first noise cancellation waveform being an inverse signal of the fundamental frequency of the actual single blade, and the second noise cancellation waveform being an inverse signal of the fundamental frequency of the actual blade passage frequency. in, This active noise cancellation controller is also used for: Measure the actual frequency response of one of the signal transmission paths between the speaker module and the error microphone; and The inverted noise signal is corrected based on the actual frequency response to provide a corrected inverted noise signal.

2. The electronic system as claimed in claim 1, characterized in that, The active noise cancellation controller includes: A frequency calculator is used to determine, based on the synchronization signal, one estimated single-blade fundamental frequency, one estimated single-blade double frequency, and one estimated BPF fundamental frequency of the fan module at each speed. A signal generator is used to perform a sound signal cutting operation, a sound signal zero-padding operation, a sound signal conversion operation and a sound signal peak determination operation on the signal detected by the error microphone to determine the actual single blade fundamental frequency, the actual blade passing frequency fundamental frequency and the actual BPF multiplier frequency when the fan module operates at each speed. as well as A digital filter is used to perform operations on the phase compensation signal to determine a reference power value for the speaker control signal.

3. The electronic system as described in claim 2, characterized in that, The error microphone is also used to detect a noise signal generated when the fan module operates at a specific speed. The speaker module also plays one of the noise signals, a BPF fundamental frequency signal, which is a first dynamic phase sine wave containing multiple sequence lengths; The active noise reduction controller is further used to set the phase corresponding to the sequence with the lowest power in the first dynamic phase sine wave as the phase offset of the BPF fundamental frequency signal in the noise signal; After playing the BPF fundamental frequency signal of the noise signal, the speaker module further plays at least one N-fold frequency signal of the noise signal, the at least one N-fold frequency signal being a second dynamic phase sine wave containing a plurality of sequence lengths; The active noise reduction controller is further configured to set the phase corresponding to the sequence with the lowest power in the second dynamic phase sine wave as the phase offset of the at least one N-fold harmonic signal in the noise signal. as well as N is an integer greater than 1.

4. The electronic system as claimed in claim 2, characterized in that, The active noise cancellation controller also includes: An adaptive filter is used to adjust the parameters used by the digital filter when performing operations based on the phase compensation signal and the error signal, thereby adaptively adjusting the power value of the speaker control signal.

5. The electronic system as claimed in claim 4, characterized in that, The adaptive filter system uses a least mean square algorithm to process the phase compensation signal and the error signal.

6. The electronic system as claimed in claim 4, characterized in that, The active noise cancellation controller also includes: A secondary path compensation transfer function module, coupled to the embedded controller, receives the estimated signal of the secondary path and then corrects the phase compensation signal based on the estimated signal of the secondary path to provide a corrected phase compensation signal; and A noise weighting and conversion module is used to process the error signal according to a specific signal weighting method and a specific signal conversion method to provide a processed error signal, wherein: This secondary path relates to the signal transmission path between the speaker module and the error microphone; and The adaptive filter adjusts the parameters used by the digital filter when performing operations based on the corrected phase compensation signal and the processed error signal.

7. The electronic system as claimed in claim 6, characterized in that, The active noise cancellation controller also includes: The secondary path transfer function module is used to measure the actual frequency response of the secondary path and then correct the inverted noise signal accordingly to provide a corrected inverted noise signal.

8. The electronic system as claimed in claim 6, characterized in that, The active noise cancellation controller is further used to adjust the parameters used by the digital filter when performing the operation based on the corrected phase compensation signal and the processed error signal, thereby adaptively adjusting the power value of the speaker control signal to reduce the value of the error signal.

9. The electronic system as claimed in claim 1, characterized in that, The error microphone is located at the air outlet of the fan module.

10. The electronic system as claimed in claim 1, characterized in that, This active noise cancellation controller is also used for: The embedded controller receives an estimated frequency response from one of the signal transmission paths between the speaker module and the error microphone; and The phase compensation signal is corrected based on the estimated frequency response to provide a corrected phase compensation signal.

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