High-speed response power control method and system for engine power turbine shaft

Abstract

The invention discloses a high-speed response power control method and system for an engine power turbine shaft, and the method comprises the steps: calculating a torque limit value MKP limit value of the engine power turbine shaft under a power limit value condition based on the rotating speed, collected in real time, of the power turbine shaft; based on the torque Mkp measured value, collected in real time, of the power turbine shaft, the deviation value epsilon (t) of the current Mkp measured value-MKP limit value is calculated, and then the engine fuel flow limit value Wf limit value is obtained through calculation; and the engine fuel flow is limited not to exceed the engine fuel flow limit value Wf, so that the engine power turbine shaft torque does not exceed the limit value. According to the method, starting from two influence factors of the power of the power turbine shaft of the engine, two parameters of the rotating speed and the torque of the power turbine shaft of the engine are introduced, so that the power limit target value is more accurate, and the precision is higher; according to the method, the engine power is reduced directly by limiting the fuel flow of the engine, adjustment response lag caused by other factors such as an intermediate conversion link is avoided, and the method has the advantages of being simple in control method, high in response speed, high in control precision and wide in application range and has good practicability.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation engine control, and in particular relates to a power control method and system for a high-speed response engine power turbine shaft. Background Art

[0002] The turboshaft engine numerical control system is used to control the turboshaft engine. It is necessary to limit the output power of the turboshaft engine power turbine shaft to prevent the torque of the engine power turbine shaft from exceeding its allowable limit value or exceeding the input torque limit of the helicopter main reducer, so as to ensure that the engine works safely within the working envelope. At present, the turboshaft engine numerical control system controls the engine state by adjusting the engine fuel flow rate to keep the speed of the engine power turbine shaft constant at 100% speed or other specified values. After the engine enters the idle slow state, the higher the engine fuel flow rate, the higher the speed Ng of the engine gas generator, and the higher the output torque and output power of the engine power turbine; conversely, the smaller the engine fuel flow rate, the lower the speed Ng of the engine gas generator, and the lower the output torque and output power of the engine power turbine.

[0003] One or more torque sensors are installed on the output shaft of the turboshaft engine power turbine, and the torque value of the turboshaft engine power turbine output shaft is calculated by the output signal of the torque sensor. After the torque value of the turboshaft engine power turbine output shaft reaches its limit requirement value, the engine is not allowed to increase its state and output more power to avoid over-torque of the engine power turbine shaft; or after the torque of the engine power turbine output shaft exceeds the limit value, the engine state is reduced to reduce its output power. The existing method of limiting the output power of the power turbine shaft is mainly achieved by limiting the speed Ng of the engine gas generator: first, the torque function f(Mkp 测量值 ,MKP 限制值 ) is converted into a limiting function of the rotation speed Ng; then, the torque of the engine power turbine output shaft is indirectly regulated by limiting the rotation speed Ng of the engine gas generator, so that the output power of the engine power turbine output shaft does not exceed the limit. However, the above limiting method has the following disadvantages:

[0004] 1) The control method is complex: the existing method needs to convert the torque of the engine power turbine output shaft into the engine gas generator Ng through the PID control method; then limit the speed of the engine gas generator Ng, indirectly realizing the limitation of the torque of the engine power turbine output shaft;

[0005] 2) Large control error: According to the engine output power calculation formula, the engine output power is affected by two parameters: the speed and torque of the engine power turbine shaft. Therefore, even if the torque does not exceed the limit value, when the speed is higher, the output power of the engine power turbine output shaft will exceed the limit value;

[0006] 3) The power limiting process responds slowly: When the engine power turbine shaft is transiently over-torqued, the limit value converted into the speed Ng after adjustment is higher than the speed Ng adjustment demand value caused by the transient static droop of the engine power turbine shaft speed. Therefore, torque limitation will not be performed. It is necessary to wait until the engine power turbine shaft speed adjustment is stable before responding to the torque limitation, which will cause a delay in the adjustment response. Summary of the invention

[0007] The object of the present invention is to provide a high-speed response engine power turbine shaft power control method and system, aiming to solve the above-mentioned problems.

[0008] The present invention is mainly achieved through the following technical solutions:

[0009] A high-speed response power control method for an engine power turbine shaft comprises the following steps:

[0010] Step S1: Based on the real-time collected speed of the power turbine shaft, calculate the torque limit value MKP of the engine power turbine shaft under the power limit value condition 限制值 ;

[0011] Step S2: Based on the torque Mkp of the power turbine shaft acquired in real time 测量值 , calculate the current Mkp 测量值 -MKP 限制值 The deviation value ε(t) of the engine fuel flow limit value Wf is calculated. 限制值 :

[0012]

[0013] Where: Wfb is the current torque limit value MKP 限制值 The corresponding basic value of engine fuel flow;

[0014] Kp is the error amplification factor;

[0015] Ti is the error integration period;

[0016] Limit the starting fuel flow to not exceed the engine fuel flow limit value Wf 限制值 , so that the engine power turbine shaft torque does not exceed the limit value.

[0017] In order to better implement the present invention, further, in the step S1, according to power = (torque × speed) / 9550, the torque limit value MKP under the power limit value condition is calculated. 限制值 .

[0018] In order to better implement the present invention, further, in the step S1, a two-dimensional table of engine power turbine shaft speed-engine power turbine shaft torque is constructed, and based on the real-time collected power turbine shaft speed, the two-dimensional table is searched to obtain the engine power turbine shaft torque, and the torque limit value MKP is used as 限制值 .

[0019] In order to better implement the present invention, further, in step S2, a two-dimensional table of engine power turbine shaft torque-engine fuel flow is constructed based on the torque limit value MKP in step S1. 限制值 , look up the two-dimensional table to obtain the engine fuel flow rate, and use it as the engine fuel flow rate basic value Wfb.

[0020] In order to better implement the present invention, further, a two-dimensional table of engine power turbine shaft torque-engine fuel flow is constructed based on the engine bench test method.

[0021] In order to better implement the present invention, further, step S2 includes the following steps:

[0022] Step S21: Based on the torque Mkp of the power turbine shaft collected in real time 测量值 , calculate the current Mkp 测量值 -MKP 限制值 The deviation value ε(t) is used to calculate PI based on the deviation value ε(t) to obtain WfPI:

[0023]

[0024] Step S22: Based on the torque limit value MKP in step S1 限制值 , find the two-dimensional table of engine power turbine shaft torque-engine fuel flow to obtain the engine fuel flow basic value Wfb;

[0025] Step S23: Calculate the current engine fuel flow limit value Wf 限制值 =Wfb+WfPI, limiting the fuel flow rate to not exceed the engine fuel flow rate limit value Wf 限制值 .

[0026] The present invention is mainly achieved through the following technical solutions:

[0027] A high-speed response engine power turbine shaft power control system, based on the above-mentioned high-speed response engine power turbine shaft power control method, includes a torque measurement module, a speed measurement module, a torque limit value calculation module, a torque limit basic fuel flow calculation module, a fuel flow limit value calculation module and a fuel flow control module;

[0028] The torque measurement module is used to obtain the output torque of the turboshaft engine power turbine shaft through a torque sensor, and the speed measurement module is used to obtain the output speed of the turboshaft engine power turbine shaft through a speed sensor;

[0029] The torque limit value calculation module is used to calculate the torque limit value MKP of the engine power turbine shaft by using the output speed and power limit of the turboshaft engine power turbine shaft 限制值 ;

[0030] The torque limit basic fuel flow calculation module is used to calculate the torque limit value MKP based on the 限制值 Look up the table to obtain the basic value of engine fuel flow Wfb;

[0031] The fuel flow limit value calculation module is used to calculate the fuel flow limit value based on the engine fuel flow base value Wfb and the output torque of the turboshaft engine power turbine shaft and the torque limit value MKP of the engine power turbine shaft. 限制值 The PI calculation result of the deviation value ε(t) is used to calculate the engine fuel flow limit value Wf 限制值 ;

[0032] The fuel flow control module is used to control the fuel flow based on the engine fuel flow limit value Wf 限制值 , controls the fuel regulator of the turboshaft engine, thereby changing the temperature and pressure of the combustion chamber, and regulating the power of the fuel turbine and power turbine.

[0033] The beneficial effects of the present invention are as follows:

[0034] 1) The power limiting method is simple: the present invention controls the output torque of the engine power turbine shaft by directly limiting the engine fuel flow rate; the power limiting process of the present invention no longer needs to convert the torque limit into the engine gas engine speed Ng limit, and then indirectly limit the engine power turbine shaft torque by limiting the Ng speed;

[0035] 2) The power limit target value is more accurate and has higher precision: Based on the two influencing factors of the engine power turbine shaft power, the present invention introduces two parameters, the speed and torque of the engine power turbine shaft, to make the power limit target value more accurate and has higher precision;

[0036] 3) The power limiting process responds faster: When the output power of the engine power turbine shaft exceeds the limit value, the present invention directly reduces the engine power by limiting the engine fuel flow, avoiding other factors such as intermediate conversion links that cause delayed regulation response. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a flow chart of the power control method of the engine power turbine shaft with high-speed response of the present invention;

[0038] Figure 2 It is a principle block diagram of the power control system of the engine power turbine shaft with high-speed response of the present invention. DETAILED DESCRIPTION

[0039] Embodiment 1:

[0040] A high-speed response power control method for an engine power turbine shaft comprises the following steps:

[0041] (1) Based on the collected turboshaft engine power turbine shaft speed, according to the calculation formula of power turbine shaft power = (torque × speed) / 9550, the torque limit value MKP corresponding to the power limit value condition at different speeds of the engine power turbine shaft is obtained. 限制值 ;

[0042] (2) According to the formula: Set the current Mkp 测量值 -MKP 限制值 Substitute the deviation value ε(t) into the calculation formula to obtain the engine fuel flow limit value Wf 限制值 ; Directly control the engine fuel flow so that the engine output power does not exceed the limit value.

[0043] The invention has the advantages of simple control method, fast response speed, high control accuracy and wide application. The invention directly controls the engine fuel flow rate without conversion through intermediate links, and has a fast response speed; when calculating the torque limit value, the engine power turbine speed is introduced, so that the accuracy of the engine power turbine shaft power limit is higher.

[0044] Embodiment 2:

[0045] A high-speed response power control method for an engine power turbine shaft, such as Figure 1 As shown, the following steps are included:

[0046] ① Collect the rotation speed of the turboshaft engine power turbine shaft;

[0047] ② According to the calculation formula of torque = (output power × 9550) / speed, the torque limit value MKP of the power turbine shaft corresponding to the power limit value conditions at different speeds is obtained. 限制值 ;

[0048] ③ Collect the torque of the turboshaft engine power turbine shaft;

[0049] ④Calculate the current Mkp 测量值 -MKP 限制值 The deviation value ε(t) is used to calculate PI based on the deviation value ε(t) to obtain the result WfPI:

[0050]

[0051] ⑤ Torque limit value MKP based on the power turbine shaft 限制值 , determine the engine fuel flow base value Wfb;

[0052] ⑥Finally, add the PI calculation result WfPI and the engine fuel flow base value Wfb corresponding to the current limit value to obtain the current engine fuel flow limit value Wf 限制值 =Wfb+WfPI, thereby limiting the engine fuel flow to not exceed this limit value, making the engine power turbine shaft torque not exceed the limit value, and ultimately achieving the power turbine shaft power limitation.

[0053] Preferably, the turboshaft engine power turbine shaft power calculation formula is: power = (torque × speed) / 9550, and a two-dimensional table is set in the turboshaft engine numerical control system software. The table contains engine power turbine shaft torque values ​​corresponding to different engine power turbine shaft speeds that are pre-calculated, wherein one dimension is the engine power turbine shaft speed N2, and the other dimension is the engine power turbine shaft torque Mkp; the turboshaft engine numerical control system software collects and calculates the current engine power turbine shaft speed N2 in each control cycle, and uses the N2 speed to find the position corresponding to the current speed in the engine power turbine shaft speed N2 dimension in the two-dimensional table, and then finds the Mkp value corresponding to this position in the engine power turbine shaft torque Mkp dimension in the two-dimensional table, which is the MKP limit value. The collection and calculation of the current engine turbine shaft speed is the same as the prior art, so it will not be repeated here.

[0054] Among them, Mkp 测量值 The current engine power turbine shaft torque value Mkp collected and calculated by the turboshaft engine numerical control system. The current engine power turbine shaft torque value Mkp collection and calculation is the same as the prior art, so it will not be repeated.

[0055] Preferably, the current MKP 限制值 The corresponding engine fuel flow base value Wfb can be obtained through the engine bench test method. A two-dimensional table is set in the turboshaft engine numerical control system software, in which the corresponding engine fuel flow Wf under different engine power turbine shaft torque Mkp measured in advance by the engine bench test method is shown, one dimension of which is the engine power turbine shaft torque Mkp, and the other dimension is the engine fuel flow Wf; the turboshaft engine numerical control system software searches for the position corresponding to the current MKP limit value in the engine power turbine shaft torque Mkp dimension in the two-dimensional table in each control cycle according to the current MKP limit value, and then searches for the Wf value corresponding to this position in the engine fuel flow Wf dimension in the two-dimensional table, which is Wfb.

[0056] Embodiment 3:

[0057] A high-speed response power control system for an engine power turbine shaft, such as Figure 2 As shown, it includes a fuel regulator, a combustion chamber, a gas turbine, a power turbine, a main reducer, a rotor, a torque sensor, a speed sensor, a torque measurement module, a speed measurement module, a power limit setting module, a torque limit value calculation module, a torque limit basic fuel flow calculation module, a fuel flow limit value calculation module, and a fuel flow control module, wherein the fuel regulator, the combustion chamber, the gas turbine, and the power turbine belong to a turboshaft engine, the main reducer and the rotor belong to a helicopter, and the torque measurement module, the speed measurement module, and the fuel flow control module are all prior arts, so they are not described in detail.

[0058] The torque measurement module obtains the output torque of the power turbine shaft of the turboshaft engine through a torque sensor, the speed measurement module obtains the output speed of the power turbine shaft of the turboshaft engine through a speed sensor, and the torque limit value calculation module uses the power turbine shaft output speed N2 measured by the speed measurement module and the power limit value given by the power limit value giving module, and uses the formula: power = (torque × speed) / 9550 to calculate the torque limit value corresponding to this power.

[0059] The torque limit basic fuel flow calculation module has a built-in two-dimensional data table for calculating the current MKP 限制值 The corresponding engine fuel flow basic value Wfb is obtained by the engine bench test method when the engine power turbine shaft output torque reaches MKP 限制值 The fuel flow rate at this time is a mature technology, so it will not be repeated here. The data table shows the corresponding engine fuel flow rate Wf under different power turbine shaft torque Mkp of the engine measured by the pre-engine bench test method, one dimension of which is the engine power turbine shaft torque Mkp, and the other dimension is the engine fuel flow rate Wf.

[0060] The fuel flow limit value calculation module calculates the current Mkp obtained by the torque measurement module. 测量值 and the MKP of the previous moment 限制值 Subtract to get the deviation value ε(t), and use the calculation formula Get the fuel flow correction value; add the fuel flow correction value WfPI to the engine fuel flow base value Wfb corresponding to the current MKP limit value calculated by the torque limit basic fuel flow calculation module to get the current engine fuel flow limit value Wf 限制值 =Wfb+WfPI.

[0061] The fuel flow control module calculates Wf based on the fuel flow limit value calculation module 限制值Control the fuel regulator of the turboshaft engine to change the temperature and pressure of the combustion chamber, so that the power of the fuel turbine and the power turbine is reduced according to the reduction of the fuel flow limit value, and finally the output power of the turboshaft engine power turbine shaft is limited when it exceeds the limit value.

[0062] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A high-speed response engine power turbine shaft power control method, characterized in that: The following steps are involved: Step S1: Based on the real-time collected speed of the power turbine shaft, calculate the torque limit value MKP of the engine power turbine shaft under the power limit value condition 限制值 ; Step S2: Based on the torque Mkp of the power turbine shaft acquired in real time 测量值 , calculate the current Mkp 测量值 -MKP 限制值 The deviation value ε(t) of the engine fuel flow limit value Wf is calculated. 限制值 : Where: Wfb is the current torque limit value MKP 限制值 The corresponding basic value of engine fuel flow; Kp is the error amplification factor; Ti is the error integration period; Limit the starting fuel flow to not exceed the engine fuel flow limit value Wf 限制值 , so that the engine power turbine shaft torque does not exceed the limit value.

2. A high-speed response engine power turbine shaft power control method according to claim 1, characterized in that: In step S1, the torque limit value MKP under the power limit value condition is calculated according to power=(torque×speed) / 9550. 限制值 .

3. A high-speed response engine power turbine shaft power control method according to claim 2, characterized in that: In the step S1, a two-dimensional table of engine power turbine shaft speed-engine power turbine shaft torque is constructed, and based on the real-time collected power turbine shaft speed, the torque of the engine power turbine shaft is obtained by searching the two-dimensional table and serving as the torque limit value MKP 限制值 .

4. The method for controlling the power of a high-speed response engine power turbine shaft according to claim 1, characterized in that: In step S2, a two-dimensional table of engine power turbine shaft torque-engine fuel flow is constructed based on the torque limit value MKP in step S1. 限制值 , look up the two-dimensional table to obtain the engine fuel flow rate, and use it as the engine fuel flow rate basic value Wfb.

5. A high-speed response engine power turbine shaft power control method according to claim 4, characterized in that: A two-dimensional table of engine power turbine shaft torque-engine fuel flow is constructed based on the engine bench test method.

6. A high-speed response engine power turbine shaft power control method according to claim 4, characterized in that: The step S2 comprises the following steps: Step S21: Based on the torque Mkp of the power turbine shaft collected in real time 测量值 , calculate the current Mkp 测量值 -MKP 限制值 The deviation value ε(t) is used to calculate PI based on the deviation value ε(t) to obtain WfPI: Step S22: Based on the torque limit value MKP in step S1 限制值 , find the two-dimensional table of engine power turbine shaft torque-engine fuel flow to obtain the engine fuel flow basic value Wfb; Step S23: Calculate the current engine fuel flow limit value Wf 限制值 =Wfb+WfPI, limiting the fuel flow rate to not exceed the engine fuel flow rate limit value Wf 限制值 .

7. A high-speed response engine power turbine shaft power control system, based on the high-speed response engine power turbine shaft power control method according to any one of claims 1 to 6, characterized in that: It includes a torque measurement module, a speed measurement module, a torque limit value calculation module, a torque limit basic fuel flow calculation module, a fuel flow limit value calculation module and a fuel flow control module; The torque measurement module is used to obtain the output torque of the turboshaft engine power turbine shaft through a torque sensor, and the speed measurement module is used to obtain the output speed of the turboshaft engine power turbine shaft through a speed sensor; The torque limit value calculation module is used to calculate the torque limit value MKP of the engine power turbine shaft by using the output speed and power limit of the turboshaft engine power turbine shaft 限制值 ; The torque limit basic fuel flow calculation module is used to calculate the torque limit value MKP based on the 限制值 Look up the table to obtain the basic value of engine fuel flow Wfb; The fuel flow limit value calculation module is used to calculate the fuel flow limit value based on the engine fuel flow base value Wfb and the output torque of the turboshaft engine power turbine shaft and the torque limit value MKP of the engine power turbine shaft. 限制值 The PI calculation result of the deviation value ε(t) is used to calculate the engine fuel flow limit value Wf 限制值 ; The fuel flow control module is used to control the fuel flow based on the engine fuel flow limit value Wf 限制值 , controls the fuel regulator of the turboshaft engine, thereby changing the temperature and pressure of the combustion chamber, and regulating the power of the fuel turbine and power turbine.

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