Permanent magnet water pump system for wafer manufacturing temperature control equipment and control method

Abstract

The invention discloses a permanent magnet water pump system for wafer manufacturing temperature control equipment and a control method, and belongs to the technical field of semiconductor manufacturing. The system comprises a permanent magnet synchronous motor, a magnetic coupler, an impeller, a pump cavity and a controller. The magnetic coupler achieves non-contact torque transmission through the driving half shaft, the driven half shaft and the isolation sleeve, heat conduction is isolated, and motor parameters are prevented from being affected by temperature. The controller estimates magnetic coupling angle deviation by utilizing a nonlinear elastic angle-torque relation based on a position-sensorless algorithm, realizes high-precision rotor angle estimation in combination with current information, and has intelligent protection functions of slipping, locking, idling and the like. The problems that a traditional alternating current asynchronous motor is narrow in speed regulation range and poor in low-speed load and a permanent magnet motor parameter temperature excursion are solved, and the alternating current asynchronous motor has the advantages of being wide in speed range, high in precision, high in reliability, high in adaptability and the like and is suitable for high-cleanliness and high-precision temperature control scenes in wafer manufacturing.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a permanent magnet water pump system and control method for temperature control equipment in wafer manufacturing. Background Technology

[0002] Referring to patents CN116266062B, CN115129092B, and CN117213291A, during wafer manufacturing, it is necessary to ensure the efficient and stable transfer of heat or cold in the temperature control or refrigeration system. As a core component driving the flow of circulating fluid, the efficient and precise control of the water pump is particularly important. For example, in the metal-oxide-semiconductor (MOSFET) process, during the gate oxide layer growth process, temperature fluctuations need to be controlled within ±1℃, which places even higher demands on the control precision of the water pump.

[0003] Traditional water pump systems connect the motor and load via a mechanical shaft, often using an AC asynchronous motor. In traditional systems, even though the mechanical shaft may conduct heat, the inherent parameters of the electrically excited AC asynchronous motor do not change significantly with temperature variations. However, AC asynchronous motors suffer from limited speed range and low-speed load differentials, failing to meet the higher precision and efficiency requirements of wafer manufacturing temperature control equipment. Furthermore, permanent magnet synchronous motors, with their built-in permanent magnets eliminating the need for induction excitation, avoid the rotor excitation losses of AC asynchronous motors. They also offer superior efficiency and higher power density across the entire load range, making them a more energy-efficient alternative.

[0004] To address the above problems, this invention provides a permanent magnet water pump system and control method for temperature control equipment in wafer manufacturing. The system uses a permanent magnet synchronous motor as the main body of the pump and a magnetic shaft to connect the motor to the load. Using a permanent magnet synchronous motor allows for a wider speed range; using a magnetic shaft isolates temperature transmission, avoiding changes in the motor's parameters when controlled without position sensors. However, permanent magnet synchronous motors require accurate rotor angles when driven by vector control; and when using a magnetic shaft connection, there is a magnetic coupling angle deviation between the active and passive half-shafts. The main challenge in replacing an AC asynchronous motor with a rigid shaft with a permanent magnet synchronous motor and magnetic shaft is to balance this magnetic coupling angle deviation and achieve a rotor angle estimation that better matches the system. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a permanent magnet water pump system and control method for temperature control equipment in wafer manufacturing, thereby solving the problems of: 1) the limited speed range, low-speed load difference, and high energy consumption of AC asynchronous motor water pumps; 2) the influence of temperature on the body parameters of water pumps using permanent magnet synchronous motors; and 3) the difficulty in obtaining angle estimation when using permanent magnet synchronous motors with magnetic shafts.

[0006] This invention provides a permanent magnet water pump system for temperature control equipment in wafer manufacturing, comprising: a permanent magnet synchronous motor, a magnetic coupling, an impeller, a pump chamber, and a controller;

[0007] The magnetic coupling includes an active half-shaft, a passive half-shaft, and an isolation sleeve; the controller includes a current sampling and conversion module, a magnetic coupling angle estimation module, a rotor angle estimation module, a protection logic module, and an inverter drive module.

[0008] The permanent magnet synchronous motor and the magnetic coupling are connected to the driving half-shaft, and the impeller and the magnetic coupling are connected to the driven half-shaft. The isolation sleeve is used for spatial isolation between the driving half-shaft and the driven half-shaft.

[0009] The controller is connected to the permanent magnet synchronous motor (PMSM) for controlling and driving the PMSM. Specifically: the inverter drive module in the controller is connected to the PMSM for driving the PMSM; the current sampling and conversion module is connected to the inverter drive module and the rotor angle estimation module, for obtaining the phase current of the PMSM from the inverter drive module, and then calculating the direct-axis current and quadrature-axis current by rotating coordinate transformation based on the estimated rotor angle; the magnetic coupling angle estimation module is connected to the current sampling and conversion module, for calculating the magnetic coupling angle deviation based on the direct-axis current and quadrature-axis current; the rotor angle estimation module is connected to the magnetic coupling angle estimation module and the current sampling and conversion module, for estimating the rotor angle based on the magnetic coupling angle deviation and current information; and the protection logic module is connected to the magnetic coupling angle estimation module, for determining the operating condition of the PMSM and executing protection measures.

[0010] This invention provides a control method for a permanent magnet water pump system in a temperature control equipment for wafer manufacturing, comprising the following steps:

[0011] Sensorless rotor angle estimation:

[0012] Step 1: Sample the phase current of the permanent magnet synchronous motor and obtain the direct-axis current and quadrature-axis current through rotating coordinate transformation;

[0013] Step 2: Calculate the electromagnetic torque based on the main parameters of the permanent magnet synchronous motor, the direct-axis current and quadrature-axis current from Step 1;

[0014] Step 3: Input the electromagnetic torque from Step 2 into the nonlinear elastic angle-torque relationship formula to solve for the magnetic coupling deviation angle of the magnetic coupling;

[0015] Step 4: Calculate the load electrical angle based on the currently estimated rotor angle, the number of pole pairs of the permanent magnet synchronous motor, and the magnetic coupling deviation angle;

[0016] Step 5: Calculate the electrical angle error based on the currently estimated rotor angle and load electrical angle.

[0017] ε coupl =θ e_est -θ e_load

[0018] In the formula, θ e_est For the estimated rotor angle, θ e_load For the load electrical angle, ε coupl This refers to electrical angle error;

[0019] Step 6: Calculate the total error based on the electrical angle error and back EMF error, or calculate the total error based on the electrical angle error and flux linkage error; send the total error to the PI controller and output the estimated rotor angular velocity;

[0020] Step 7: Integrate the estimated rotor angular velocity to obtain a new estimated rotor angle, completing the sensorless rotor angle calculation closed loop; apply the rotor angle, which takes into account the magnetic coupling deviation angle information, to the vector control of the permanent magnet synchronous motor to achieve precise operation of the permanent magnet synchronous motor plus magnetic coupling system;

[0021] Protection and control:

[0022] The tripping angle of the magnetic coupling is Δθ max When the magnetic coupling deviation angle is greater than 85% Δθ max At this point, the permanent magnet synchronous motor is decelerated until the magnetic coupling deviation angle is less than 80% Δθ. max ;

[0023] When the magnetic coupling deviation angle is approximately 0 and the electromagnetic torque of the permanent magnet synchronous motor is not zero, slippage is determined, and the motor is stopped immediately.

[0024] Optionally, in step 2, the main body parameters of the permanent magnet synchronous motor and the direct-axis current i are... d and cross-axis current i q To calculate electromagnetic torque T em Specifically, these include:

[0025] T em =1.5p[ψ f i q +(L d -L q )i d i q ]

[0026] Where, ψ f For the permanent magnet flux linkage of a permanent magnet synchronous motor, L q L d These are the quadrature-axis inductance and direct-axis inductance of a permanent magnet synchronous motor.

[0027] Optionally, in step 3, the magnetic coupling angle deviation Δθ is calculated by: setting T = T emSubstituting into the nonlinear elastic angle-torque relationship formula T=K1Δθ+K2Δθ 3 The magnetic coupling angle deviation Δθ is obtained.

[0028] Optionally, the first-order coefficients K1 and third-order coefficients K2 are obtained from static tests by slowly rotating the motor end, recording the torque-angle curve, and fitting it using least squares.

[0029] Optionally, in step 4, the currently estimated rotor angle θ e_est The load electrical angle θ is calculated using the number of pole pairs p of the permanent magnet synchronous motor and the magnetic coupling deviation angle Δθ. e_load =(θ e_est / p-Δθ)·p.

[0030] Optionally, in step 6, the total error can be calculated using the following methods:

[0031] If the sensorless rotor angle observer uses the back EMF observation method, based on the back EMF error ε bemf The total error ε in the calculation of electrical angle error total =ε bemf +K coupl sin(ε coupl );

[0032] Back potential error ε bemf The specific method of obtaining it is:

[0033]

[0034] Among them, R s L s For the resistance and inductance of the permanent magnet synchronous motor body, i α i β For the α and β axis currents of the permanent magnet synchronous motor after coordinate transformation, u α u β These are the α and β axis voltages after the phase voltage coordinate transformation of the permanent magnet synchronous motor. These are the observed values ​​of the α and β shaft phase currents of the permanent magnet synchronous motor. τ1 and τ2 are the observed back EMF values ​​of the α and β axes of the permanent magnet synchronous motor, respectively, and the observed coefficients.

[0035] If the sensorless rotor angle observer uses the nonlinear flux linkage method, based on the flux linkage error ε... flux The total error in the electrical angle error calculation is calculated by taking the total error ε. total =ε flux +K coupl sin(ε coupl ).

[0036] flux linkage error ε flux The specific method of obtaining it is:

[0037]

[0038] Among them, R s i is the resistance of the permanent magnet synchronous motor body. α i β For the α and β axis currents of the permanent magnet synchronous motor after coordinate transformation, u α u β These are the α and β axis voltages after the phase voltage coordinate transformation of the permanent magnet synchronous motor. These are the observed values ​​of the α and β axis flux linkages of the permanent magnet synchronous motor.

[0039] Optionally, K coupl K is a dimensionless weighted gain used to compensate for coupling. When the speed of the permanent magnet synchronous motor is less than 10% of its rated speed, K... coupl Setting it to 0, the linearity of the high-speed region is increased to

[0040] Optionally, when using the traditional three-stage method to start the permanent magnet synchronous motor, the estimated initial value of the rotor angle is assigned from the open-loop angle of the IF starting stage; or, when using the high-frequency injection method to identify the static angle, the estimated initial value of the rotor angle is assigned from the angle identified by the high-frequency injection; or, after the rotor angle is estimated in step 7, the rotor angle is updated cyclically.

[0041] The present invention has at least the following beneficial effects:

[0042] 1. Wide speed range, high precision control, and greater energy efficiency. Replacing the traditional AC asynchronous motor with a permanent magnet synchronous motor significantly widens the speed range and improves low-speed load capacity, meeting the stringent requirements of wafer manufacturing for high precision and high response in temperature control systems. Especially in variable load scenarios involving water pumps, the permanent magnet synchronous motor and frequency converter system achieves energy savings of over 25% compared to traditional AC asynchronous motors.

[0043] 2. Temperature isolation and parameter stability. A magnetic coupling enables contactless torque transmission between the motor and pump body, effectively isolating heat conduction and preventing parameter changes in the permanent magnet motor due to temperature drift, thus ensuring the stability of sensorless control.

[0044] 3. Sensorless angle estimation improves reliability. An innovative magnetic coupling angle deviation model is introduced, combined with current sampling and nonlinear elastic angle-torque relationship, to achieve high-precision rotor angle estimation without position sensors. This reduces system complexity and cost, and improves long-term operational reliability.

[0045] 4. Intelligent protection mechanism to prevent failure. Based on real-time monitoring of magnetic coupling angle and electromagnetic torque, it features multiple protection strategies including slippage detection, seizure protection, and idling speed reduction to prevent equipment damage or process interruption, improving system safety and maintenance convenience. It is suitable for high-cleanliness, high-precision temperature control scenarios in wafer manufacturing. Slippage refers to the passive half-shaft rotating faster than the drive shaft due to a sudden decrease in load, or the coupling angle becoming too advanced. Seizure refers to the passive half-shaft failing to rotate due to mechanical failure. Idling refers to the passive half-shaft being underloaded, causing the corresponding water pump pipeline to close and preventing water flow.

[0046] 5. Self-tuning of nonlinear parameters, strong adaptability. Through static testing and least squares fitting, the nonlinear stiffness coefficients (K1, K2) of the magnetic coupling are automatically extracted, enabling accurate modeling and rapid adaptation of different coupling models, enhancing the system's versatility and scalability. Attached Figure Description

[0047] The features and advantages of the invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the invention in any way. In the drawings:

[0048] Figure 1 This is a schematic diagram of a permanent magnet water pump system for a temperature control equipment in wafer manufacturing, according to a specific embodiment of the present invention.

[0049] Figure 2 This is a schematic diagram of rotor angle estimation for a permanent magnet water pump based on back EMF observation, according to a specific embodiment of the present invention.

[0050] Figure 3 This is a schematic diagram of rotor angle estimation for a permanent magnet water pump based on nonlinear flux linkage observation, according to a specific embodiment of the present invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0052] like Figure 1 As shown, a permanent magnet water pump system for temperature control equipment in wafer manufacturing includes: a permanent magnet synchronous motor 1, a magnetic coupling 2, an impeller 3, a pump chamber 4, and a controller 5.

[0053] The magnetic coupling 2 includes a driving half-shaft 21, a driven half-shaft 22, and an isolation sleeve 23. The controller 5 includes a current sampling and conversion module 51, an inverter drive module 52, a magnetic coupling angle estimation module 53, a rotor angle estimation module 54, and a protection logic module 55.

[0054] The permanent magnet synchronous motor 1 and the magnetic coupling 2 are connected to the active half shaft 21, the impeller 3 and the passive half shaft 22 of the magnetic coupling 2 are connected, and the isolation sleeve 23 is used for spatial isolation between the active half shaft 21 and the passive half shaft 22.

[0055] The controller 5 is connected to the permanent magnet synchronous motor 1 and is used to control and drive the permanent magnet synchronous motor 1. Specifically, the controller includes: an inverter drive module 52 connected to the permanent magnet synchronous motor 1 to drive the permanent magnet synchronous motor 1; a current sampling and conversion module 51 connected to the inverter drive module 52 and the rotor angle estimation module 54 to obtain the phase current of the permanent magnet synchronous motor 1, and to calculate the direct-axis current and quadrature-axis current by estimating the rotor angle and performing a rotational coordinate transformation; a magnetic coupling angle estimation module 53 connected to the current sampling and conversion module 51 to calculate the magnetic coupling angle deviation based on the direct-axis current and quadrature-axis current; a rotor angle estimation module 54 connected to the magnetic coupling angle estimation module 53 and the current sampling and conversion module 51 to estimate the rotor angle based on the magnetic coupling angle deviation and current information; and a protection logic module 55 connected to the magnetic coupling angle estimation module 54 to determine the operating condition of the permanent magnet synchronous motor and execute protection.

[0056] like Figure 2 As shown, in a control method for a permanent magnet water pump system used in wafer manufacturing temperature control equipment, when the back electromotive force observation method is adopted, the rotor angle estimation method is as follows:

[0057] S1: Sample the phase current i of the permanent magnet synchronous motor a i b i c The direct-axis current i is obtained through Clark-Park coordinate transformation. d and cross-axis current i q ;

[0058] S2: Based on the body parameters of the permanent magnet synchronous motor: permanent magnet flux linkage ψ f quadrature axis inductance L q Direct-axis inductor L d The electromagnetic torque T is calculated using the direct-axis current and quadrature-axis current from step S1. em =1.5p[ψ f i q +(L d -L q )i d i q ];

[0059] S3: The electromagnetic torque T = T in step S2 is... em Substituting into the nonlinear elastic angle-torque relationship T=K1Δθ+K2Δθ 3 Formula for calculating the magnetic coupling deviation angle Δθ of the magnetic coupling;

[0060] S4: Based on the currently estimated rotor angle θ e_est The load electrical angle θ is calculated using the number of pole pairs p of the permanent magnet synchronous motor and the magnetic coupling deviation angle Δθ. e_load =(θ e_est / p-Δθ)·p;

[0061] S5: Based on the currently estimated rotor angle θ e_est Load electrical angle θ e_load Calculate the electrical angle error ε coupl =θ e_est -θ e_load ;

[0062] S6: Based on back electromotive force error Electrical angle error ε coupl Calculate the total error ε total =ε bemf +K coupl sin(ε coupl The total error is fed into the PI controller, which outputs the estimated rotor angular velocity ω. e_est =k p ε total +k i ∫ε total dt;

[0063] S7: Integrating the estimated rotor angular velocity yields a new estimated rotor angle θ. e_est =∫ω e_est dt, to complete the closed loop of sensorless rotor angle calculation.

[0064] like Figure 3 As shown, in a control method for a permanent magnet water pump system used in wafer manufacturing temperature control equipment, the specific implementation method uses a nonlinear flux observer, and the rotor angle estimation method is as follows:

[0065] The specific difference lies in the magnetic flux error. The total error in the electrical angle error calculation is calculated by taking the total error ε. total =ε flux +K coupl sin(ε coupl ).

[0066] The nonlinear elastic angle-torque relationship is T = K1Δθ + K2Δθ 3K1 and K2 are obtained through static testing. The entire process of obtaining K1 and K2 involves treating the magnetic coupling as a torsion spring of unknown stiffness, measuring a discrete "torque-torsion angle" curve under static, slow, and inertia-free conditions, and then uniquely solving for K1 and K2 using least squares (or linear regression). Specifically:

[0067] Test platform setup: 1. Motor end: Servo driver + permanent magnet synchronous motor (with 23-bit absolute encoder, resolution 0.005°). 2. Load end: Hysteresis dynamometer (or magnetic powder brake) + second 23-bit encoder (high-precision circular grating can also be used). 3. Intermediate: Magnetic coupling under test (active half connected to the motor shaft, passive half connected to the dynamometer shaft). 4. Data acquisition: Torque flange (accuracy 0.1%) + two encoder angles, sampling frequency 1kHz.

[0068] Experimental steps:

[0069] Step B1: Zeroing. Set the dynamometer to "position lock" mode, with the angle locked at 0°. Slowly rotate the current loop at the motor end until the torque flange reading is just greater than 0, and record the motor encoder angle θ0 at this point. Define Δθ = θ motor -θ load -θ0.

[0070] Step B2: Sampling at equal intervals. The dynamometer remains locked at 0°. The motor end rotates forward at an extremely low speed of 0.1° / s, pausing for 0.5 seconds after every 0.2° rotation, and the steady-state torque T is recorded. i With corresponding Δθ i Continue tightening until T reaches the tripping torque T specified by the manufacturer. max 85% (leaving a 15% safety margin) yields n≈50 sets of discrete points (Δθ) i ,T i ).

[0071] Step B3: Repeat the test in reverse. Rotate in the opposite direction using the same method and take another 50 points to check the hysteresis symmetry; if the difference between the forward and reverse directions is less than 2%, they can be used together; otherwise, the "average curve" can be used subsequently.

[0072] Step B4: Data Preprocessing. Eliminate the starting friction dead zone: Δθ < 0.05° and T < 0.02T. max The points are discarded (nonlinear friction region, not used to fit elasticity). The remaining m groups (Δθ) i ,T i (Then proceed to the next step of the regression.)

[0073] Step B5: Solve for K1 and K2 using least squares, adopting the model: T = K1·Δθ + K2·Δθ3, written in matrix form:

[0074]

[0075] Using the normal equation: x=(A T A) -1 A T b. Solve using MATLAB to obtain K1 and K2. K1 has dimensions [N·m / rad], and K2 has dimensions [N·m / rad]. 3 ].

[0076] For example, a certain -20 pole magnetic coupling, measured values: K1 = 42.7 N·m / rad, K2 = -195.2 N·m / rad 3 Tripping angle Δθ max ≈0.153rad≈8.8°.

[0077] Protection and control:

[0078] The tripping angle of the magnetic coupling is Δθ max When the magnetic coupling deviation angle is greater than 85% Δθ max At this time, the permanent magnet synchronous motor is decelerated until the magnetic coupling deviation angle Δθ is less than 80%; among them, 85% is taken to leave a safety margin, and 80% is taken to retain hysteresis.

[0079] When the magnetic coupling deviation angle is approximately 0, the electromagnetic torque T of the permanent magnet synchronous motor em If the motor does not reach zero speed, it will detect slippage and immediately stop.

[0080] In the experimental case, Δθ max =8.8°, the rated torque of the permanent magnet synchronous motor is denoted as TN.

[0081] Experimental Case 1 (Seizure Condition)

[0082] Step a1: The impeller is manually jammed, and controller 5 samples T. em It rises to 1.8 times TN within 1 ms, with an estimated Δθ of 8.3° (≈0.95Δθ). max , );

[0083] Step b1: Protection logic 55 immediately limits the speed of permanent magnet synchronous motor 1 to 20% of its rated speed and reports a fault;

[0084] Step c1: If the fault is not resolved after 1 second, controller 5 stops driving permanent magnet synchronous motor 1.

[0085] Experimental Case 2 (Outlet valve closed - idling)

[0086] Step a2: Valve closed, flow rate approaches 0, T em The value of Δθ decreased from 0.8 times TN to 0.1 times TN, and the estimated value of Δθ decreased from 5° to 0.3°.

[0087] Step b2: The protection logic determines "idling" and automatically reduces the speed to 20% standby. Normal operation resumes after the valve reopens, with no overcurrent throughout the process.

[0088] As described above, this invention offers high-precision speed-range control and greater energy efficiency. By replacing the traditional AC asynchronous motor with a permanent magnet synchronous motor, the speed range is significantly broadened, and low-speed load capacity is improved, meeting the stringent requirements of wafer manufacturing for high precision and high response in temperature control systems. Especially in variable load scenarios for water pumps, the permanent magnet synchronous motor and frequency converter system achieves energy savings of over 25% compared to traditional AC asynchronous motors. This invention provides temperature isolation and parameter stability. A magnetic coupling enables contactless torque transmission between the motor and pump body, effectively isolating heat conduction and preventing parameter changes in the permanent magnet motor due to temperature drift, ensuring the stability of sensorless control. This invention also features sensorless angle estimation, improving reliability. An innovative magnetic coupling angle deviation model is introduced, combined with current sampling and nonlinear elastic angle-torque relationships, to achieve high-precision rotor angle estimation without position sensors, reducing system complexity and cost, and improving long-term operational reliability. Finally, this invention incorporates an intelligent protection mechanism to prevent failure. Based on real-time monitoring of magnetic coupling angle and electromagnetic torque, this invention features multiple protection strategies, including slippage detection, lock-up protection, and idling speed reduction, to prevent equipment damage or process interruption, improving system safety and maintenance convenience. It is suitable for high-cleanliness, high-precision temperature control scenarios in wafer manufacturing. This invention also features self-tuning of nonlinear parameters, offering strong adaptability. Through static testing and least-squares fitting, the nonlinear stiffness coefficients (K1, K2) of the magnetic coupling are automatically extracted, enabling accurate modeling and rapid adaptation for different coupling models, enhancing system versatility and scalability.

[0089] It is evident that those skilled in the art can obtain various effects from the various structures according to embodiments of the present invention, which are not directly mentioned in the less cumbersome embodiments. Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the present invention. Other modifications can be readily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

Claims

1. A permanent magnet water pump system for temperature control equipment in wafer manufacturing, characterized in that, Includes: permanent magnet synchronous motor, magnetic coupling, impeller, pump chamber, and controller; The magnetic coupling includes an active half-shaft, a passive half-shaft, and an isolation sleeve; the controller includes a current sampling and conversion module, a magnetic coupling angle estimation module, a rotor angle estimation module, a protection logic module, and an inverter drive module. The permanent magnet synchronous motor is connected to the active half-shaft of the magnetic coupling, the impeller is connected to the passive half-shaft of the magnetic coupling, and the isolation sleeve is used for spatial isolation between the active half-shaft and the passive half-shaft. The controller is connected to the permanent magnet synchronous motor and is used to control and drive the permanent magnet synchronous motor based on the estimated rotor angle.

2. The permanent magnet water pump system for temperature control equipment in wafer manufacturing as described in claim 1, characterized in that, The inverter drive module in the controller is connected to the permanent magnet synchronous motor (PMSM) and is used to drive the PMSM. The current sampling and conversion module is connected to the inverter drive module and the rotor angle estimation module. It is used to obtain the phase current of the PMSM from the inverter drive module, and then calculate the direct-axis current and quadrature-axis current by rotating coordinate transformation based on the estimated rotor angle. The magnetic coupling angle estimation module is connected to the current sampling and conversion module and is used to calculate the magnetic coupling angle deviation based on the direct-axis current and quadrature-axis current. The rotor angle estimation module is connected to the magnetic coupling angle estimation module and the current sampling and conversion module and is used to estimate the rotor angle based on the magnetic coupling angle deviation and current information. The protection logic module is connected to the magnetic coupling angle estimation module and is used to determine the operating condition of the PMSM and execute protection.

3. A control method for a permanent magnet water pump system in a temperature control equipment for wafer manufacturing, characterized in that, Includes the following steps: Step 1: Sample the phase current of the permanent magnet synchronous motor and obtain the direct-axis current and quadrature-axis current through rotating coordinate transformation; Step 2: Calculate the electromagnetic torque based on the main parameters, direct-axis current, and quadrature-axis current of the permanent magnet synchronous motor; Step 3: Input the electromagnetic torque into the nonlinear elastic angle-torque relationship formula to calculate the magnetic coupling deviation angle of the magnetic coupling; Step 4: Calculate the load electrical angle based on the currently estimated rotor angle, the number of pole pairs of the permanent magnet synchronous motor, and the magnetic coupling deviation angle; Step 5: Calculate the electrical angle error based on the currently estimated rotor angle and load electrical angle; Step 6: Calculate the total error based on the electrical angle error and back EMF error, or calculate the total error based on the electrical angle error and flux linkage error; send the total error to the PI controller and output the estimated rotor angular velocity; Step 7: Integrate the estimated rotor angular velocity to obtain a new estimated rotor angle, completing the closed loop of sensorless rotor angle calculation; The rotor angle, which takes into account the magnetic coupling deviation angle information, is applied to the vector control of the permanent magnet synchronous motor to achieve precise control of the permanent magnet synchronous motor plus magnetic coupling system.

4. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 3, characterized in that, It also includes protection controls: The tripping angle of the magnetic coupling is Δθ max When the magnetic coupling deviation angle is greater than 85% Δθ max At this point, the permanent magnet synchronous motor is decelerated until the magnetic coupling deviation angle is less than 80% Δθ. max ; When the magnetic coupling deviation angle approaches 0 and the electromagnetic torque of the permanent magnet synchronous motor is not zero, slippage is detected, and the motor is controlled to stop.

5. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 3, characterized in that, In step 5, the electrical angle error is calculated as follows: e coupl =θ e_est -θ e_load In the formula, θ e_est For the estimated rotor angle, θ e_load For the load electrical angle, ε coupl This refers to the electrical angle error.

6. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 5, characterized in that, In step 2, based on the body parameters of the permanent magnet synchronous motor and the direct-axis current i d and cross-axis current i q To calculate electromagnetic torque T em The method is as follows: T em =1.5p[ψ f i q +(L d -L q )i d i q ] Where, ψ f For the permanent magnet flux linkage of a permanent magnet synchronous motor, L q L d These are the quadrature-axis inductance and direct-axis inductance of a permanent magnet synchronous motor, respectively.

7. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 6, characterized in that, In step 3, the method for solving the magnetic coupling angle deviation angle Δθ is as follows: T = T em Substituting into the nonlinear elastic angle-torque relationship formula T=K1Δθ+K2Δθ 3 The magnetic coupling angle deviation angle Δθ is obtained; the first-order coefficient K1 and the third-order coefficient K2 are obtained from the static test: the torque-angle curve is recorded at the rotating motor end during the test and obtained by least squares fitting.

8. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 7, characterized in that, In step 4, the currently estimated rotor angle θ e_est The load electrical angle θ is calculated using the number of pole pairs p of the permanent magnet synchronous motor and the magnetic coupling deviation angle Δθ. e_load =(θ e_est / p-Δθ)·p.

9. A control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 8, characterized in that, In step 6, the total error is calculated using the following methods: If the rotor angle observer without a position sensor uses the back EMF observation method, based on the back EMF error ε bemf The total error ε in the calculation of electrical angle error total =ε bemf +K coupl sin(ε coupl ); Back potential error ε bemf The method to obtain it is as follows: Among them, R s L s For the resistance and inductance of the permanent magnet synchronous motor body, i α i β For the α and β axis currents of the permanent magnet synchronous motor after coordinate transformation, u α u β These are the α and β axis voltages after the phase voltage coordinate transformation of the permanent magnet synchronous motor. These are the observed values ​​of the α and β shaft phase currents of the permanent magnet synchronous motor. τ1 and τ2 are the observed back EMF values ​​of the α and β axes of the permanent magnet synchronous motor, respectively; If the rotor angle observer without a position sensor uses the nonlinear flux linkage method, based on the flux linkage error ε flux The total error in the electrical angle error calculation is calculated by taking the total error ε. total =ε flux +K coupl sin(ε coupl ); flux linkage error ε flux The method to obtain it is: Among them, R s i is the resistance of the permanent magnet synchronous motor body. α i β For the α and β axis currents of the permanent magnet synchronous motor after coordinate transformation, u α u β These are the α and β axis voltages after the phase voltage coordinate transformation of the permanent magnet synchronous motor. These are the observed values ​​of the α and β axis flux linkages of the permanent magnet synchronous motor; K coupl K is a dimensionless weighted gain used to compensate for coupling. When the speed of the permanent magnet synchronous motor is less than 10% of its rated speed, K... coupl Set to 0; improve linearity in the high-speed region to 10. The control method for a permanent magnet water pump system in a wafer manufacturing temperature control equipment as described in claim 3, characterized in that, When the traditional three-stage method is used to start the permanent magnet synchronous motor, the estimated initial value of the rotor angle is assigned by the open-loop angle of the IF starting stage; or, when the high-frequency injection method is used to identify the static angle, the initial value is assigned by the angle identified by the high-frequency injection; after the rotor angle is estimated in step 7, the rotor angle will be updated cyclically.

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