An electromagnetic actuator temperature compensation method based on timing length translation and variable time length scaling bidirectional correction

Abstract

The application discloses an electromagnetic actuator temperature compensation method based on timing length translation and variable time length scaling bidirectional correction, and aims at solving the problem that the dynamic characteristics of electromagnets are deteriorated due to the continuous heating of energized coils and the change of ambient temperature of the electromagnetic actuator applied to the gas volume regulation of a reciprocating compressor. The method comprises the following steps: S1, determining a control parameter target value and a response time curve family; S2, judging the influence mode of temperature rise on the response time of the electromagnetic actuator, and selecting a corresponding timing length translation or variable time length scaling compensation method for compensation. The compensation method can effectively restore the displacement output response of the electromagnetic actuator, and avoid the problem that the dynamic characteristics of the electromagnet are deteriorated due to the temperature change, thereby affecting the gas volume regulation effect of the reciprocating compressor.

Description

Technical Field

[0001] This invention is based on an electromagnetic actuator for regulating the air volume of a reciprocating compressor. It proposes a temperature compensation method for the electromagnetic actuator based on bidirectional correction of timed long translation and variable time scaling, which effectively solves the problem of deterioration of the dynamic characteristics of the electromagnet caused by temperature changes. Background Technology

[0002] Reciprocating compressors, as a type of positive displacement compressor, are widely used in petrochemical, coal chemical, oil and gas extraction, metallurgy, refrigeration, gas storage, and natural gas transportation. They are not only core equipment in the energy industry but also energy-intensive power equipment. To address the common problems of mismatched operating conditions and inability to adaptively adjust to different system requirements, it is necessary to regulate the gas flow rate of reciprocating compressors to meet varying production demands. Among numerous gas flow rate regulation methods, the partial-stroke top-opening inlet valve regulation method, with its ability to achieve precise 0-100% gas flow rate control and significant energy-saving effects, has been widely adopted in the petrochemical and natural gas industries.

[0003] Currently, most domestic air volume control systems rely on hydraulic actuators to partially open the intake valve for regulation. This involves mounting the actuator on the intake valve and using hydraulic pressure to drive its extension and retraction, thereby controlling the valve's opening and closing. An example is the HydroCOM hydraulic air volume control system (CN03158561.2) developed by Hoerbiger GmbH in Austria. However, hydraulic air volume control systems require a dedicated hydraulic system, and each valve needs its own hydraulic actuator and hydraulic lines for inlet, return, and leakage recovery. Therefore, hydraulic air volume control systems suffer from complex structures and are prone to leaks.

[0004] Replacing hydraulic drive with electromagnetic drive can effectively solve the above problems. Furthermore, electromagnetic actuators offer advantages such as fast response, easy installation, and sensitive adjustment. However, the dynamic characteristics of electromagnetic actuators are highly sensitive to temperature changes. The continuous heating of the electromagnet's energized coil and changes in ambient temperature inevitably lead to variations in the electromagnet's operating temperature, resulting in varying degrees of deterioration in the dynamic characteristics of the electromagnetic actuator. This ultimately reduces the accuracy of airflow regulation and increases load adjustment deviation, negatively impacting the compressor's flow control performance and stable operation.

[0005] Common electromagnet temperature compensation methods are divided into direct and indirect methods. Direct temperature compensation requires an additional temperature compensation device, increasing equipment costs. Indirect methods typically compensate the output of the electromagnetic actuator by adjusting the drive current or the PWM duty cycle. For example, patent CN105179671A provides a temperature compensation method for a proportional solenoid valve based on constant current control. However, this method increases energy loss during the voltage boosting process, and excessive current further exacerbates the temperature rise. Patent CN109000025A discloses a solenoid valve control system with temperature compensation that indirectly compensates the temperature of the electromagnetic coil by adjusting the PWM duty cycle. However, this temperature compensation method cannot be effectively applied to the temperature compensation of air volume regulating electromagnetic actuators. In some scenarios, such as when changes in electromagnet temperature cause changes in both the time the actuator completes ejection and the time it holds at the maximum displacement, adjusting the PWM duty cycle alone cannot provide effective compensation. Furthermore, due to the high frequency and large driving force characteristics of air volume regulating electromagnetic actuators, they have an adjustment dead zone and a limited adjustable duty cycle range. The PWM duty cycle adjustment method cannot achieve compensation across the entire air volume load range. Summary of the Invention

[0006] To address the problem of deterioration in the dynamic characteristics of electromagnetic actuators caused by temperature variations, this invention proposes a temperature compensation method for electromagnetic actuators based on bidirectional correction using time-duration translation and variable-duration scaling. The method is characterized by:

[0007] This invention is based on an electromagnetic actuator for regulating the air volume of a reciprocating compressor, the structure of which and its working principle are as follows:

[0008] (1) Structure as follows Figure 1 As shown, this electromagnetic actuator is a moving iron type electromagnet with a fixed coil. The armature and push rod are the moving parts of the actuator, and the two are connected by threads.

[0009] (2) Figure 2 The schematic diagram illustrates the working process of this electromagnetic actuator: When a positive excitation signal is applied to the coil, the coil begins to charge, increasing the electromagnetic force. When the electromagnetic force exceeds the spring's reaction force, the armature is attracted downwards, causing the push rod to push downwards. The push rod then pushes the unloading device's fork to force open the intake valve, allowing gas in the cylinder to flow back to the intake chamber through the intake valve. When the positive excitation signal is applied completely, the electromagnetic force gradually decreases. When the electromagnetic force is less than the spring's reaction force, the armature and push rod retract, the valve closes, and the remaining gas remains in the cylinder for compression. This electromagnetic actuator, combined with the partial-stroke intake valve opening technology, enables stepless gas volume regulation in a reciprocating compressor.

[0010] The dynamic response parameters of the electromagnetic actuator under a given load are as follows:

[0011] When an excitation voltage signal is applied to the electromagnet coil, the electromagnetic actuator drives the air valve to open and close. A schematic diagram of its dynamic response is shown below. Figure 3 As shown. T S The working cycle of the electromagnetic actuator is equal to one working cycle of the reciprocating compressor. T1 is the time from receiving the key phase signal to the actuator completing the ejection action. T2 is the time from the ejection action to the completion of the retraction action of the electromagnetic actuator. T3 is the time from the completion of the retraction action of the electromagnetic actuator to the end of the working cycle. t is the forward energization time of the electromagnetic actuator.

[0012] T1, T2, and T3 are the time response parameters of the electromagnet, T S = 60 / n, in seconds, where n is the compressor speed. T S It is determined solely by the compressor speed and does not change with the excitation voltage signal, and T3 = T s Since T1 and T2 are considered as the target control parameters during the operation of the electromagnetic actuator, the control process is simplified. The process for determining T1 and T2 is as follows:

[0013] (1) Determine the operating parameters based on the working conditions and production requirements, including: reciprocating compressor speed n, reciprocating compressor load K, and crankshaft angle θ when the intake valve is pushed out at 100% load. P Among them, the crankshaft angle θ when the intake valve pushes out at 100% load. P It can be calculated from the expansion process.

[0014] (2) The intake valve delay closing time can be derived from the operating parameters.

[0015] (3) Determine the power supply method: This electromagnetic actuator can achieve delayed closure of the intake valve through two power supply methods: variable duration and fixed duration. The variable duration power supply method changes the duty cycle t / T of the excitation voltage signal. s The timed long-term power supply method is achieved by delaying or advancing the power supply, such as... Figures 4 to 6 As shown, t0 is the forward voltage delay time; t0>0 indicates delayed power-on, and t0<0 indicates early power-on. Keeping t0 constant, the duty cycle t / T is increased... s To extend T2, thus delaying the intake valve's closing time, this method uses variable-duty-time scaling adjustment; maintaining the duty cycle t / T. s By keeping T2 constant and increasing t0, the ejection time of the electromagnet can be delayed, thus achieving delayed closing of the intake valve. This method involves timed long-distance adjustment. To ensure that the electromagnetic actuator ejects during the compressor intake process, the target response time can be determined sequentially based on the operating conditions and parameters. and

[0016]

[0017]

[0018] in, Can be in the range Choose any value from the options.

[0019] The control processes of T1 and T2 are achieved by adjusting the forward energizing time t and the delayed energizing time t0. Furthermore, the response characteristic curves of T1-t and T2-t at t0=0 within the operating temperature range of the actuator can be obtained by fitting experimental data as follows: keeping the temperature constant, from t=0.5T... S Initially, increment t by 1 ms. When the electromagnetic actuator can fully extend, record the t value after each 1 ms increment, along with the corresponding T1 and T2 values, until the electromagnetic actuator can no longer fully retract. Repeat the above steps for each set of temperatures within the actuator's operating range, and fit the obtained experimental data into T1-t and T2-t curves, as shown below. Figures 7 to 8 As shown. Where q i Let i be the operating temperature, i = 1, 2, ..., n. q min Minimum operating temperature, q max Let t0 be the maximum operating temperature and Δq be the temperature gradient. When t0 ≠ 0, the value of T2 is still equal to the value of T2 when t0 = 0, and the value of T1 is equal to the value of T1 when t0 = 0 plus the value of t0 at this moment.

[0020] The ranges of T2 and t can be obtained through the following experimental test: reduce the forward energizing time t until the electromagnetic actuator can no longer eject; the minimum values ​​of T2 and t in this critical state are respectively... min and t min Increase the forward energizing time t until the electromagnetic actuator can no longer be withdrawn. The critical state T2 and t are its maximum values ​​T and T, respectively. max and t max When T2 is not in (T min ,T max ) within the range or t not within (t) min ,t max When the range is within ), the electromagnetic actuator cannot work properly.

[0021] When the electromagnet experiences a temperature rise Δq within one cycle, it causes T1 and T2 to deviate from their set values, resulting in a change in the displacement output waveform of the actuator. The displacement output change caused by temperature variation can be categorized into three cases: displacement waveform shift, waveform scaling, and simultaneous translation and scaling. These three cases can be specifically represented as follows:

[0022]

[0023] Where T1' and T2' are the response time parameters after the temperature drift occurs, and ΔT and α represent the offset of T1 and the scaling of T2 caused by the temperature change, respectively.

[0024] To ensure the accuracy of air volume regulation, temperature compensation is needed to adjust T1 and T2 back to the target values ​​for the electromagnetic actuator. This method indirectly compensates the electromagnetic actuator by reconfiguring the excitation signal parameters t and t0 through variable-duration scaling and timing-duration translation. Figures 9 to 10 As shown.

[0025] The specific implementation steps of this method are as follows:

[0026] S1 determines the target values ​​of the control parameters and the family of response time curves, including the following steps:

[0027] S1.1 Referring to the formula described above, determine the target response time sequentially based on the operating conditions and production requirements.

[0028] S1.2 Referring to the experimental data fitting method described above, a family of T1-t curves (t0=0) at different temperatures and a family of T2-t curves at different temperatures are obtained, and the initial values ​​t' and t0' of t and t0 are determined according to the families of curves.

[0029] S2 determines the impact of temperature rise on the response time of the electromagnetic actuator and selects the appropriate time-duration translation or variable-duration scaling compensation method for compensation, including the following steps:

[0030] S2.1 Measure the temperature change Δq of the electromagnet.

[0031] S2.2 Observe the T1-t curve family and T2-t curve family at the initial temperature q and (q+Δq) respectively, and determine the type of change in the displacement waveform output. If the temperature change only causes the displacement waveform to scale, go to S2.3; if the temperature change causes the displacement waveform to shift and scale simultaneously, go to S2.4; if the temperature change only causes the displacement waveform to shift, go to S2.5.

[0032] S2.3 Locate the T2-t curve at temperature (q+Δq) on the family of T2-t curves, and determine the range of this curve (T) using the experimental testing methods described above. min ,T max ),like or If this exceeds the adjustment range of this method, an alarm message will be output; if Then, use variable duration scaling adjustment to draw a straight line. The curve intersects the curve at a point, and the x-coordinate of this point is taken as the new positive energizing time, denoted as t". Due to the existence of residual magnetism, a change in t will cause a change in T1. Therefore, after the variable duration adjustment, the time-duration translation adjustment method needs to be used again, and then proceed to S2.5.

[0033] S2.4 Locate the T2-t curve at temperature (q+Δq) on the family of T2-t curves, and determine the range of this curve (T) using the experimental testing methods described above. min ,T max ),like or If this exceeds the adjustment range of this method, an alarm message will be output; if Then, use variable duration scaling adjustment to draw a straight line. The curve intersects with the curve at a point, and the x-coordinate of this point is taken as the new positive energizing time, denoted as t". At this point, the adjustment of T2 has ended. In order to adjust T1 while keeping T2 unchanged, the timing shift adjustment is switched to S2.5.

[0034] S2.5 Locate the T1-t curve at temperature (q+Δq) on the family of T1-t curves (t0=0), and determine the domain of this curve (t) using the experimental testing method described above. min ,t max Let x = t n , where t n For the forward power supply time at this moment, if t n ≤t min or t n ≥t max If t exceeds the adjustment range of this method, an alarm message will be output; min < n <t max Then, using timed long-distance translation adjustment, draw the straight line x = t. n The curve intersects at a point, and the ordinate of this intersection point is labeled T1'. Let... After calculating △T1, let the compensation amount for the delayed positive power supply time be △t0 = △T1, and add △t0 to the delayed positive power supply time t0' before the control to obtain the new delayed positive power supply time t0.

[0035] The principle flowchart of the whole process is as follows: Figure 11 As shown Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of the electromagnetic air volume regulating actuator of the reciprocating compressor involved in this invention;

[0037] 1. Outer shell 2. Coil 3. Limiting plate 4. Push rod 5. Pole shoe

[0038] 6. Armature 7. Screw 8. Mounting hole

[0039] Figure 2 This is a schematic diagram illustrating the working principle of the electromagnetic air volume regulating actuator for the reciprocating compressor involved in this invention.

[0040] Figure 3 This is a schematic diagram showing the excitation voltage signal and the displacement output signal of the actuator during one working cycle of the compressor.

[0041] Figure 4 A schematic diagram showing the excitation voltage signal and the displacement output signal of the actuator when the intake valve closes on time.

[0042] Figure 5 This is a schematic diagram showing the excitation voltage signal and the actuator displacement output signal when the intake valve is delayed in closing by adjusting the time.

[0043] Figure 6 This is a schematic diagram showing the excitation voltage signal and the actuator displacement output signal when the intake valve is delayed in closing by adjusting the time length.

[0044] Figure 7 This is a schematic diagram of the T1-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing.

[0045] Figure 8 This is a schematic diagram of the T2-t response characteristic curve of the actuator within its operating temperature range, obtained through experimental testing.

[0046] Figure 9 This is a schematic diagram illustrating the principle of temperature compensation through variable duration scaling.

[0047] Figure 10 This is a schematic diagram illustrating the principle of temperature compensation through timed long-distance translation adjustment.

[0048] Figure 11 This is a flowchart illustrating a temperature compensation method for an electromagnetic actuator based on bidirectional correction of timed long translation and variable duration scaling proposed in this invention.

[0049] Figure 12 The T1-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 1 is shown.

[0050] Figure 13 The T2-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 1 is shown.

[0051] Figure 14 The T1-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 2 is shown.

[0052] Figure 15 The T2-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 2 is shown.

[0053] Figure 16 The T1-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 3 is shown.

[0054] Figure 17 The T2-t response characteristic curve of the actuator within the operating temperature range obtained through experimental testing in Example 3 is shown. Detailed Implementation

[0055] Example 1:

[0056] Taking a reciprocating compressor with an operating speed of 300 r / min, an intake pressure of 0.1 MPa, an exhaust pressure of 0.3 MPa, and an electromagnetic actuator with 4100 coil turns, a coil diameter of 40 mm, a spring stiffness coefficient of 70000 N / m, and an operating temperature range of 20℃-45℃ as an example. Assume the initial operating temperature is 30℃.

[0057] S1 determines the target values ​​of the control parameters and the family of response time curves:

[0058] S1.1 Reciprocating compressor speed n = 300 r / min, working cycle T s =200ms, crankshaft angle θ when intake valve pushes out at 100% load P =40°. According to production requirements, the load needs to be adjusted from K=100% to K=50%. Therefore, the intake valve delay closing time can be determined:

[0059]

[0060] Therefore, it can be determined

[0061]

[0062] Pick Then it can be further determined

[0063]

[0064] S1.2 A family of T1-t curves (t0=0) and a family of T2-t curves at 20℃-45℃ were fitted using experimental data, as shown below. Figure 12 and Figure 13 As shown. The initial operating temperature is 30℃, according to... Figure 11 and Figure 12 We know that t' = 132 ms. Among them, T 10The initial value of T1 is when t0 = 0.

[0065] S2 determines the impact of temperature rise on the response time of the electromagnetic actuator and selects the appropriate time-duration translation or variable-duration scaling compensation method for compensation.

[0066] S2.1 The temperature change Δq = 5℃ was measured.

[0067] S2.2 According to Figure 12 and Figure 13 It was found that when the temperature changed to 35 degrees Celsius, the T2 value remained unchanged, while the T1 value changed, indicating that the temperature rise caused the overall shift of the displacement waveform.

[0068] S2.5 according to Figure 12 At 35℃, t can be determined using the experimental testing method described above. max =135ms,t min =121ms, at this time t n =t'=132ms,t min < n <t max Using a timed long-distance translation adjustment, a straight line x = 132 ms is plotted. This straight line intersects the T1-t curve at 35℃ at a single point. The ordinate of this intersection point is marked as T1' = 87 ms. Let the compensation amount of the delayed positive power supply time be Δt0 = ΔT1. Add Δt0 to the delayed positive power supply time t0' before the control, and get the new delayed positive power supply time t0” = -48 + 11 = -37ms.

[0069] Example 2

[0070] Taking the reciprocating compressor and electromagnetic actuator in Example 1 as an example, assume the initial operating temperature is 35℃.

[0071] S1 determines the target values ​​of the control parameters and the family of response time curves:

[0072] S1.1 Reciprocating compressor speed n = 300 r / min, working cycle T s =200ms, crankshaft angle θ when intake valve pushes out at 100% load P =40°. According to production requirements, the load needs to be adjusted from K=100% to K=90%. Therefore, the intake valve delay closing time can be determined:

[0073]

[0074] Therefore, it can be determined

[0075]

[0076] Pick Then it can be further determined

[0077]

[0078] S1.2 A family of T1-t curves (t0=0) and a family of T2-t curves at 20℃-45℃ were fitted using experimental data, as shown below. Figure 14 and Figure 15 As shown. The initial operating temperature is 35℃, according to... Figure 11 and Figure 12 We know that t' = 125 ms. Among them, T 10 The initial value of T1 is when t0 = 0.

[0079] S2 determines the impact of temperature rise on the response time of the electromagnetic actuator and selects the appropriate time-duration translation or variable-duration scaling compensation method for compensation.

[0080] S2.1 The temperature change Δq = 10℃ was measured.

[0081] S2.2 According to Figure 14 and Figure 15 It was found that when the temperature changed to 45 degrees Celsius, the T1 value remained unchanged, while the T2 value changed, indicating that the temperature rise caused the displacement waveform to scale.

[0082] S2.3 According to Figure 15 At 45℃, T can be determined using the experimental testing method described above. max =125ms,T min =4ms, Using the variable duration scaling adjustment method, draw a straight line. The positive energizing time is adjusted to the x-coordinate of the intersection point t” = 128ms. The T2-t curve at 45℃ intersects at one point.

[0083] S2.5 according to Figure 14 At 45℃, t can be determined using the experimental testing method described above. max =135ms,t min =122ms, at this time t n =t”=128ms,t min < n <t max Using a timed long-distance translation adjustment, a straight line x = 128 ms is plotted. This straight line intersects the T1-t curve at 45℃ at a single point. The ordinate of this intersection point is marked as T1' = 71 ms. Let the compensation amount for the delayed positive power supply time be Δt0 = ΔT1. Add Δt0 to the delayed positive power supply time t0' before the control, and finally obtain the new delayed positive power supply time t0” = 25 - 31 = -6ms.

[0084] Example 3:

[0085] Taking the reciprocating compressor and electromagnetic actuator in Example 1 as an example, assume the initial operating temperature is 25℃.

[0086] S1 determines the target values ​​of the control parameters and the family of response time curves:

[0087] S1.1 Reciprocating compressor speed n = 300 r / min, working cycle T s =200ms, crankshaft angle θ when intake valve pushes out at 100% load P =40°. According to production requirements, the load needs to be adjusted from K=100% to K=70%. Therefore, the intake valve delay closing time can be determined:

[0088]

[0089] Therefore, it can be determined

[0090]

[0091] Pick Then it can be further determined

[0092]

[0093] S1.2 A family of T1-t curves (t0=0) and a family of T2-t curves at 20℃-45℃ were fitted using experimental data, as shown below. Figure 16 and Figure 17 As shown. The initial operating temperature is 25℃, according to... Figure 16 and Figure 17 We know that t' = 124 ms. Among them, T 10 The initial value of T1 is when t0 = 0.

[0094] S2 determines the impact of temperature rise on the response time of the electromagnetic actuator and selects the appropriate time-duration translation or variable-duration scaling compensation method for compensation.

[0095] S2.1 The temperature change Δq = 5℃ was measured.

[0096] S2.2 According to Figure 16 and Figure 17It was found that when the temperature changed to 30 degrees Celsius, both the T1 and T2 values ​​changed, indicating that the temperature rise caused both the overall shift of the displacement waveform and the scaling of the displacement waveform.

[0097] S2.4 According to Figure 17 At 30℃, T can be determined using the experimental testing method described above. max =123ms,T min =7ms, Using the variable duration scaling adjustment method, draw a straight line. The positive energizing time is adjusted to the x-coordinate of the intersection point t” = 130ms. The T2-t curve at 30℃ intersects at one point.

[0098] S2.5 according to Figure 16 At 30℃, t can be determined using the experimental testing method described above. max =134.5ms,t min =121ms, at this time t n =t”=130ms,t min < n <t max Using a timed long-distance translation adjustment, a straight line x = 130 ms is plotted. This straight line intersects the T1-t curve at 30℃ at a single point. The ordinate of this intersection point is marked as T1' = 100 ms. Let the compensation amount for the delayed positive power supply time be Δt0 = ΔT1. Add Δt0 to the delayed positive power supply time t0' before the control, and get the new delayed positive power supply time t0” = 11 - 58 = -47ms.

Claims

1. A temperature compensation method for an electromagnetic actuator based on bidirectional correction of timed long translation and variable time scaling, characterized in that: Based on an electromagnetic actuator for regulating the air volume of a reciprocating compressor, this electromagnetic actuator is a moving iron type electromagnet with a fixed coil, and the armature and push rod are the moving parts of the actuator, which are connected by threads. Its working principle is that when a positive excitation signal is applied to the coil, the armature is attracted, the air valve is forcibly opened, and the gas flows back; when the positive excitation signal is applied, the armature is reset, the air valve is closed, and the remaining gas enters the compression stage. The electromagnetic actuator includes three dynamic response parameters: T1 is the time from receiving the key phase signal to the actuator completing the ejection action; T2 is the time from ejection to retraction; and T3 is the time from retraction to the end of the current work cycle. The working cycle of the electromagnetic actuator is T. Where n is the speed of the reciprocating compressor, and Therefore, only T1 and T2 are used as target control parameters during the operation of the electromagnetic actuator, thus simplifying the control process. The control process of T1 and T2 is achieved by adjusting the forward energizing time t and the delayed energizing time t0. The T1-t response characteristic curves and T2-t response characteristic curves at t0=0 within the operating temperature range of the actuator are obtained through the following experimental test method: keeping the temperature constant, from t=0.5T... S Initially, increment t by 1ms. When the electromagnetic actuator can fully extend, record the t value after each 1ms increment and the corresponding T1 and T2 values, until the electromagnetic actuator can no longer fully retract. Repeat the above steps for each set of temperatures within the actuator's operating range, and fit the obtained experimental data into T1-t response characteristic curves and T2-t response characteristic curves. When t0≠0, the value of T2 is still equal to the T2 value at t0=0, and the value of T1 is equal to the T1 value at t0=0 plus the t0 value at this moment. The ranges of T2 and t were obtained through the following experimental test method: The forward energizing time t was decreased until the electromagnetic actuator could no longer eject; T2 and t in this critical state were the minimum values ​​of T1 and T2, respectively. min and t min Increase the forward energizing time t until the electromagnetic actuator can no longer be withdrawn. The critical state T2 and t are its maximum values ​​T and T, respectively. max and t max ; Temperature compensation for the electromagnetic actuator is performed through the following steps: S1 determines the target values ​​of the control parameters and the family of response time curves, including the following steps: S1.1 Determine the target response time sequentially based on operating conditions and production requirements. Its expression is: ； ； Can be in the range Choose any value from θ, where θ P The crankshaft angle when the intake valve is pushed out at 100% load is calculated from the expansion process. n is the speed of the reciprocating compressor; The intake valve delay closing time is given by the formula. Confirmed; K represents the load of the reciprocating compressor; S1.2 Based on the experiment, a family of T1-t curves at different temperatures and a family of T2-t curves at different temperatures were obtained, and the initial values ​​t' and t0' of t and t0 were determined based on the families of curves. S2 determines the impact of temperature rise on the response time of the electromagnetic actuator and selects the appropriate time-duration translation or variable-duration scaling compensation method for compensation, including the following steps: S2.1 Measure the temperature change ∆q of the electromagnet; S2.2 Observe the initial temperature q and (q+∆q) respectively. Curve family and The family of curves determines the type of change in the displacement waveform output. If the temperature change only causes the displacement waveform to scale, proceed to S2.

3. If the temperature change causes both offset and scaling of the displacement waveform, proceed to S2.

4. If the temperature change only causes the displacement waveform to offset, proceed to S2.

5. S2.3 in Find the temperature (q+∆q) on the family of curves The response characteristic curve is determined according to step S1.2, and its range (T) is calculated. min ,T max ),like ≤T min or ≥T max If T exceeds the adjustment range of this method, an alarm message will be output; min < <T max Then, using variable duration scaling adjustment, draw the straight line y = The curve intersects the curve at temperature (q+∆q) at a point. The x-coordinate of this point is taken as the new positive power supply time, denoted as . Due to the presence of residual magnetism, changes in t will cause changes in T1. Therefore, after the variable duration adjustment, the time-duration translation adjustment method needs to be used again, turning to S2.5; S2.4 in Find the temperature (q+∆q) on the family of curves The curve, according to step S1.2, determines the range (T) of the curve. min ,T max ),like ≤T min or ≥T max If T exceeds the adjustment range of this method, an alarm message will be output; min < <T max Then, using variable duration scaling adjustment, draw the straight line y = The curve intersects the curve at a point, and the x-coordinate of this point is taken as the new positive power supply time, denoted as . At this point, the adjustment of T2 has ended. In order to adjust T1 while keeping T2 unchanged, switch to timed long-distance translation adjustment and switch to S2.

5. S2.5 in Find the temperature (q+∆q) on the family of curves (t0=0) Response characteristic curve, determine the domain of the curve (t) min ,t max Let x = t n , where t n For the positive power supply time at this moment, if t n ≤t min or t n ≥t max If t exceeds the adjustment range of this method, an alarm message will be output; min <t n <t max Then, using timed long-distance translation adjustment, draw the straight line x = t. n The curve intersects at a point, and the ordinate of this intersection point is labeled T1'; let... ;calculate Then, adjust the compensation amount for the delayed positive power supply time. ,Will Added to the delayed positive power supply time before regulation The new delayed positive power supply time is obtained. .

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