A control method and control system for a micro turbine engine

Abstract

The present invention discloses a control method and control system for a micro-turbine engine, which primarily includes automatic correction of the starting fuel quantity and fuel closing control. At the beginning of engine startup, an initial starting fuel quantity is given and an initial fuel supply PWM signal is output. A determination is made as to whether the speed increase rate dn is greater than a preset rate of change D. If dn is greater than D, the starting fuel quantity is decreased by a preset fuel reduction amount and a corrected fuel supply PWM signal is output. If dn is not greater than D, the starting fuel quantity remains unchanged and a current fuel supply PWM signal is output. A determination is made as to whether the fuel growth rate is less than the speed growth rate. If so, the current fuel supply PWM signal remains unchanged. If not, the fuel growth rate is equal to the limited fuel growth rate, and a limited fuel supply PWM signal is output. This method enables the micro-turbojet engine to start quickly and enter an idling state quickly, improving the start success rate. During the throttle application process from idling to rated speed, the speed response is fast and speed fluctuation is minimal.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a control method and a control system for a micro turbine engine. Background Art

[0002] A micro-turbojet engine is a complex aerodynamic and thermodynamic machine, with speeds reaching over 100,000 revolutions per minute and turbine inlet temperatures exceeding 1000°C. Its nonlinear characteristics vary dramatically with flight altitude and Mach number. Therefore, engine speed and temperature must operate within design safety limits. Typical safety protection limit designs employ a hard oil cut based on extreme over-limit judgment to protect the turbine from overheating. This simple safety protection design often results in speed fluctuations in the closed-loop speed system due to inappropriate oil cut patterns, and can even lead to accidents such as unstable combustion, fluctuating speeds, and mid-flight stalls.

[0003] Moreover, the existing open-loop oil quantity control often has oil quantity deviation, resulting in abnormal speed changes, start failure, slow speed increase after start, etc. Summary of the Invention

[0004] In view of the above shortcomings, the technical problem to be solved by the present invention is: to provide a control method and control system for a micro-turbine engine, so that the turbojet engine can have a fast response when starting, smoothly enter the slow-speed working condition, have a fast response when adding and reducing the engine, and have a strong anti-interference ability.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for controlling a micro-turbine engine comprises the following steps:

[0007] S1. Start the engine, the starting oil volume = the initial starting oil volume, and output the initial oil supply PWM signal;

[0008] S2, obtaining the engine speed increase rate dn;

[0009] S3, determining whether the speed increase change rate dn is greater than the preset change rate D;

[0010] If it is greater than, the starting oil volume is reduced according to the preset oil reduction amount, and the corresponding corrected oil supply PWM signal is output, and then S2 is executed; if it is not greater than, the current starting oil volume remains unchanged, and the corresponding current oil supply PWM signal is output;

[0011] S5. Obtain fuel growth rate and speed growth rate;

[0012] S6. Determine whether the fuel growth rate is less than the speed growth rate;

[0013] S7. If it is less than, the current fuel supply PWM signal remains unchanged; if it is not less than, the fuel growth rate = the limited fuel growth rate, and the corresponding limited fuel supply PWM signal is output.

[0014] Preferably, the S4 is specifically:

[0015] If it is greater, the corresponding preset oil reduction amount is called according to the speed increase change rate dn, the corresponding corrected oil supply PWM signal is output, and then S2 is executed.

[0016] The preferred embodiment further comprises the following steps:

[0017] S8, obtaining the actual engine speed, target speed, and feedforward fuel supply PWM signal;

[0018] S9. Using an incremental PID speed regulator, based on the actual speed, the target speed, and the feedforward oil supply PWM signal, output a corresponding first oil supply PWM signal;

[0019] S10. Control the oil pump according to the first oil supply PWM signal to stabilize the engine speed.

[0020] Preferably, after S9, the following steps are further included:

[0021] determining whether the first fuel supply PWM signal exceeds a preset amplitude;

[0022] If exceeded, it enters over-temperature protection mode;

[0023] Get the nozzle temperature T;

[0024] Determine whether the nozzle temperature T is greater than the preset Tmax-ΔT;

[0025] If it is greater than, the over-temperature protection module is triggered, and the oil reduction amount ΔQ is calculated using the formula ΔQ = X1*[T-(Tmax-ΔT)]. Then, the corrected starting oil amount Q is calculated using the formula Q = Q-ΔQ. According to the corrected starting oil amount Q, the corresponding second oil supply PWM signal is output;

[0026] If it is not greater than, exit the over-temperature protection;

[0027] S10. Control the oil pump according to the second oil supply PWM signal to stabilize the engine speed.

[0028] The preferred embodiment further comprises the following steps:

[0029] Determine whether the nozzle temperature T is greater than the preset Tmax;

[0030] If it is greater than, the oil reduction amount ΔQ is calculated using the formula ΔQ = X2 * (T-Tmax); then the corrected starting oil amount Q is calculated using the formula Q = Q-ΔQ, and the corresponding second oil supply PWM signal is output according to the corrected starting oil amount Q;

[0031] If it is not greater than, exit the over-temperature protection.

[0032] The preferred embodiment further comprises the following steps:

[0033] Determine whether the nozzle temperature T is greater than the preset Tmax+ΔT;

[0034] If it is greater than, the over-temperature protection module is triggered, and the oil reduction amount ΔQ is calculated using the formula ΔQ = X3*[T-(Tmax+ΔT)]. Then, the corrected starting oil amount Q is calculated using the formula Q = Q-ΔQ. According to the corrected starting oil amount Q, the corresponding second oil supply PWM signal is output;

[0035] If it is not greater than, exit the over-temperature protection.

[0036] In a preferred embodiment, the feedforward fuel supply PWM signal is obtained from a preset second curve diagram, wherein the second curve diagram is preset according to the engine speed and the fuel supply PWM signal.

[0037] A control system for a micro-turbine engine, comprising an electronic control unit (ECU), an oil pump, an engine, a speed sensor, a starting oil quantity correction unit, and a fuel limiting unit, each electrically connected to the ECU. The speed sensor is used to collect the engine speed and transmit it to the ECU. The starting oil quantity correction unit is used to obtain an engine speed increase rate dn and then determine whether the speed increase rate dn is greater than a preset change rate D. If so, the starting oil quantity is gradually reduced by a preset oil reduction amount and a corresponding corrected oil supply PWM signal is output to the ECU. The determination is repeated until it is no greater than the preset change rate D. If not, the current starting oil quantity remains unchanged and a corresponding oil supply PWM signal is output to the ECU. The fuel limiting unit is used to obtain a fuel growth rate and a speed growth rate and then determine whether the fuel growth rate is less than the speed growth rate. If so, the current oil supply PWM signal is output to the ECU. If not, the fuel growth rate equals a limited fuel growth rate and a corresponding limited oil supply PWM signal is output to the ECU. The control unit controls the oil pump based on the received oil supply PWM signal to control the engine speed.

[0038] Preferably, the system further includes a PID speed regulation unit, which includes an incremental PID speed regulator. The incremental PID speed regulator outputs a corresponding first oil supply PWM signal to the electronic control unit based on the actual speed, the target speed and the feedforward oil supply PWM signal. The electronic control unit controls the oil pump based on the received first oil supply PWM signal.

[0039] Preferably, the system further includes an over-temperature protection unit, which is used to generate and transmit a corresponding second oil supply PWM signal to the electronic control unit according to the nozzle temperature T when the first oil supply PWM signal exceeds a preset amplitude, and the electronic control unit adjusts the oil pump according to the received second oil supply PWM signal.

[0040] After adopting the above technical solution, the beneficial effects of the present invention are:

[0041] The control method and control system of the micro-turbine engine of the present invention mainly stabilizes the engine speed through automatic starting fuel quantity correction and fuel closing control. The automatic starting fuel quantity correction is to set an initial starting fuel quantity at the beginning of the engine start so that the initial fuel supply PWM signal can be used to control the oil pump. During the starting process, the engine speed increase rate dn is compared with the preset change rate D. When dn is greater than D, the starting fuel quantity is gradually reduced by the preset fuel reduction amount, and the corresponding corrected fuel supply PWM signal is output. The above determination is repeated until dn is no greater than D, the starting fuel quantity remains constant, and the corresponding current fuel supply PWM signal is output, indicating that the engine has successfully started. After the start is successful, the fuel growth rate and speed growth rate are obtained to determine whether the fuel growth rate is less than the speed growth rate. If so, the current fuel supply PWM signal remains unchanged. If not, the fuel growth rate is equal to the limited fuel growth rate, and the corresponding limited fuel supply PWM signal is output. As can be seen, the present invention enables the micro-turbojet engine to start quickly, quickly enter the slow state, and improve the starting success rate. During the throttle-on process from slow state to rated speed, the speed response is fast and the speed fluctuation is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a flow chart of a control method of a micro-turbine engine in the present invention;

[0043] Figure 2 This is a principle block diagram of the speed feedforward and closed-loop control in the present invention;

[0044] Figure 3 7 is a temperature protection curve diagram of the over-temperature protection unit in the embodiment;

[0045] Figure 4 It is a schematic diagram of the process of over-temperature protection in the present invention;

[0046] Figure 5It is a principle block diagram of the control system of the micro turbine engine in the present invention. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0048] Example 1:

[0049] like Figure 1 As shown, a control method for a micro-turbine engine includes the following steps:

[0050] Step S1: Start the engine, the starting oil volume = the initial starting oil volume, and output the initial oil supply PWM signal to control the oil pump;

[0051] Step S2: Obtain the engine speed increase rate dn;

[0052] Step S3, determining whether the speed increase change rate dn is greater than a preset change rate D;

[0053] Step S4: If it is greater than, that is, dn>D, the starting fuel amount is reduced according to the preset fuel reduction amount, and the corresponding corrected fuel supply PWM signal is output, and then S2 is executed; if it is not greater than, that is, dn≤D, the current starting fuel amount remains unchanged, and the corresponding current fuel supply PWM signal is output, and the engine is successfully started at this time; specifically, the preset fuel reduction amount is obtained from the first curve diagram based on the speed increase rate dn, and the first curve diagram is a curve with the speed increase rate dn and the fuel reduction amount as coordinates.

[0054] Step S5: After the engine is successfully started, obtain the fuel growth rate and the speed growth rate;

[0055] Step S6: determining whether the fuel growth rate is less than the speed growth rate;

[0056] Step S7: If it is less than, that is, the fuel growth rate < the speed growth rate, the current fuel supply PWM signal remains unchanged; if it is not less than, that is, the fuel growth rate ≥ the speed growth rate, the fuel growth rate = the limited fuel growth rate, and the corresponding limited fuel supply PWM signal is output.

[0057] The control method of the present invention mainly includes automatic correction of the starting oil quantity and fuel limitation. The automatic correction of the starting oil quantity is set based on the fact that the open-loop oil quantity control in the existing technology often has oil quantity deviation, resulting in abnormal speed changes, starting failure, slow speed increase after starting, etc.

[0058] During the motor-drag ignition stage, the starting oil quantity is in a slightly rich oil state to facilitate starting. During this stage, the engine speed is collected in real time, and the speed increase rate dn is obtained based on the speed. The speed increase rate dn is then compared with the preset change rate D. Based on the comparison result, the starting oil quantity is controlled to decrease according to the preset oil reduction amount or remain constant, so that the engine speed steadily increases to the slow-moving state at an appropriate speed increase rate, thereby solving the technical problem of starting oil quantity deviation causing abnormal speed changes and engine starting failure.

[0059] After the engine starts successfully, the engine inertia is greater than the fuel pump inertia, resulting in a relatively slow engine speed increment and insufficient intake air, leading to incomplete fuel combustion. This can cause the engine temperature to rise sharply during the start-up to slow-down phase, leading to overheating. For this reason, after the engine starts successfully, the fuel and speed are collected in real time. The fuel growth rate and speed growth rate are calculated based on the fuel and speed. The fuel growth rate is then compared with the speed growth rate. When the fuel growth rate is less than the speed growth rate, it indicates that the engine is steadily entering the slow-down state and the current fuel pump state can be maintained. When the fuel growth rate is not less than the speed growth rate, the fuel growth rate is limited to less than the speed growth rate. This limits the fuel growth rate to the speed growth rate, allowing the engine to steadily enter the slow-down state.

[0060] It can be seen that after adopting the method of the present invention, the micro turbojet engine can start quickly, quickly enter the slow-speed state, and improve the starting success rate; in the throttle process from the slow-speed state to the rated speed, the speed response is fast and the speed fluctuation is small.

[0061] like Figure 2 As shown, the control method of the present invention also includes feedforward + PID closed-loop control of the engine speed, including the following steps:

[0062] Step S8: obtaining the actual speed, target speed and feedforward fuel supply PWM signal of the engine, where the feedforward fuel supply PWM signal can be a calibration quantity in the speed open-loop control;

[0063] Step S9: using an incremental PID speed regulator to output a corresponding first fuel supply PWM signal based on the actual speed, the target speed, and the feedforward fuel supply PWM signal;

[0064] Step S10: Control the oil pump according to the first oil supply PWM signal to stabilize the engine speed.

[0065] The speed control method of the present invention is based on a feedforward oil supply PWM signal in an open-loop mode, combined with an incremental PID speed regulator based on a speed closed loop. The incremental PID speed regulator consists of a proportional part, an integral part, and a differential part based on the prediction of the speed change rate, thereby achieving rapid speed following throttle response and small steady-state speed fluctuation.

[0066] like Figure 4 As shown, in this embodiment, after step S9, the following steps are further included:

[0067] determining whether the first fuel supply PWM signal exceeds a preset amplitude;

[0068] If exceeded, it enters over-temperature protection mode;

[0069] Get the nozzle temperature T;

[0070] Determine whether the nozzle temperature T is greater than the preset Tmax-ΔT;

[0071] If it is greater than, that is, T>Tmax-ΔT, the over-temperature protection module is triggered and the fuel reduction amount ΔQ is calculated using the formula ΔQ=X1*[T-(Tmax-ΔT)]. Then, the corrected starting fuel amount Q is calculated using the formula Q=Q-ΔQ. Based on the corrected starting fuel amount Q, the corresponding second fuel supply PWM signal is output.

[0072] If it is not greater than, that is, T≤Tmax-ΔT, exit the over-temperature protection;

[0073] Step S10: Control the oil pump according to the second oil supply PWM signal to stabilize the engine speed.

[0074] The following steps are also included:

[0075] Determine whether the nozzle temperature T is greater than the preset Tmax;

[0076] If it is greater than, that is, T>Tmax, use the formula ΔQ=X2*(T-Tmax) to calculate the oil reduction amount ΔQ; then use the formula Q=Q-ΔQ to calculate the corrected starting oil amount Q, and output the corresponding second oil supply PWM signal based on the corrected starting oil amount Q;

[0077] If it is not greater than, that is, T≤Tmax-ΔT, exit the over-temperature protection.

[0078] The following steps are also included:

[0079] Determine whether the nozzle temperature T is greater than the preset Tmax+ΔT;

[0080] If it is greater than, that is, T>Tmax+ΔT, the over-temperature protection module is triggered and the fuel reduction amount ΔQ is calculated using the formula ΔQ=X3*[T-(Tmax+ΔT)]. Then, the corrected starting fuel amount Q is calculated using the formula Q=Q-ΔQ. Based on the corrected starting fuel amount Q, the corresponding second fuel supply PWM signal is output.

[0081] If it is not greater than, that is, T≤Tmax+ΔT, exit the over-temperature protection.

[0082] The feedforward fuel supply PWM signal is obtained from a preset second curve diagram, which is preset according to the engine speed and the fuel supply PWM signal.

[0083] To prevent runaway control, the output of the incremental PID speed regulator requires limiting. However, this can still lead to overheating due to excess oil. Once overheating occurs, it can cause permanent damage to the engine's turbine structure. Therefore, this situation must be avoided in the actual control of turbojet engines. Traditional overheating control methods generally use hard oil reduction after overheating. This method causes the speed to drop quickly after oil reduction, but the temperature to drop slowly, resulting in fluctuating speed hunting and even stalling.

[0084] To address the above issues, the present invention utilizes a thermocouple temperature sensor to collect nozzle temperature T, then compares it with a preset Tmax-ΔT, a preset Tmax, and a preset Tmax+ΔT. The preset Tmax-ΔT is the over-temperature protection warning temperature, Tmax is the over-temperature protection temperature, and Tmax+Tmax+ΔT is the severe over-temperature protection line. Based on the comparison results, i.e., the degree of over-temperature, the corresponding X1, X2, and X3 are retrieved, and the corresponding formula is used to derive the corresponding fuel reduction amount ΔQ. The fuel amount is reduced based on the fuel reduction amount ΔQ to control the oil pump, thereby preventing safety accidents caused by engine turbine overheating.

[0085] like Figure 3 As shown, the comparison between the nozzle temperature T and the preset Tmax-ΔT, preset Tmax, and preset Tmax+ΔT is equivalent to Figure 4 Based on the relationship between the nozzle temperature and the temperature protection level, the present invention sets three temperature protection levels: the first (Tmax-ΔT) is the over-temperature warning level, the second (Tmax) is the over-temperature protection level, and the third (Tmax+ΔT) is the severe over-temperature protection level. Fuel reduction measures of varying degrees are implemented based on the distance between the feedback nozzle temperature T and the three temperature protection levels.

[0086] Example 2:

[0087] like Figure 5 As shown, a control system for a micro-turbine engine is applied to the control method for a micro-turbine engine described in Example 1. The system includes an electronic control unit and an oil pump, an engine, a speed sensor, a temperature sensor, a starting oil quantity correction unit, and a fuel limiter unit, each electrically connected to the electronic control unit. The speed sensor is used to collect the engine speed, and the temperature sensor is used to collect the nozzle temperature T, converting them into corresponding electrical signals and transmitting them to the electronic control unit.

[0088] The starting oil quantity correction unit is used to obtain the engine speed increase rate of change dn, and then determine whether the speed increase rate of change dn is greater than the preset change rate D; if it is greater, that is, dn>D, the starting oil quantity is reduced according to the preset oil reduction amount, and the corresponding corrected oil supply PWM signal is output to the electronic control unit, and the judgment is repeated until dn≤D; if it is not greater, that is, dn≤D, the current starting oil quantity remains unchanged, and the corresponding oil supply PWM signal is output to the electronic control unit; the decrement amount is obtained from the preset first curve diagram, which is a curve diagram with the speed increase rate and the oil reduction amount as calibrated quantities; the starting oil quantity correction unit is used to make the engine speed steadily increase to the slow-moving state at an appropriate speed increase rate, thereby solving the technical problem of starting oil quantity deviation causing abnormal speed change and engine starting failure.

[0089] Among them, the fuel limiting unit is used to obtain the fuel growth rate and the speed growth rate, and then determine whether the fuel growth rate is less than the speed growth rate; if it is less than, that is, the fuel growth rate < speed growth rate, the current fuel supply PWM signal is output to the electronic control unit; if it is not less than, that is, the fuel growth rate ≥ speed growth rate, the fuel growth rate = limited fuel growth rate, and the corresponding limited fuel supply PWM signal is output to the electronic control unit; the control unit controls the oil pump according to the received oil supply PWM signal to control the engine speed; after the engine is successfully started by the fuel limiting unit, it can enter the slow-speed state at a steady speed to avoid the engine inertia being greater than the oil pump inertia, the engine speed increment is relatively lagging, the intake air is relatively insufficient, resulting in incomplete fuel combustion, and the engine temperature may rise sharply from the start to the slow-speed stage, causing overheating.

[0090] The system also includes a PID speed control unit, which includes an incremental PID speed regulator. The incremental PID speed regulator outputs a corresponding first oil supply PWM signal to the electronic control unit based on the actual speed, target speed and feedforward oil supply PWM signal. The electronic control unit controls the oil pump based on the received first oil supply PWM signal. Figure 2 PID speed control unit realizes fast speed following throttle response and small steady-state speed fluctuation

[0091] The system also includes an over-temperature protection unit, which is used to generate and transmit a corresponding second oil supply PWM signal to the electronic control unit according to the nozzle temperature T when the first oil supply PWM signal exceeds a preset amplitude. The electronic control unit adjusts the oil pump according to the received second oil supply PWM signal. Figure 3 and Figure 4 , use the over-temperature protection unit to achieve over-temperature protection to avoid safety accidents.

[0092] like Figure 5As shown, the control system of the micro-turbine engine of the present invention uses an initial PWM signal to control the oil pump at the initial stage of engine starting. After starting, the electronic control unit starts the starting oil quantity correction unit to automatically correct the starting oil quantity. Specifically, the starting oil quantity is corrected in real time by using the speed increase change rate. For example, the starting oil quantity is reduced according to a preset oil reduction amount or the current starting oil quantity is kept constant. This realizes automatic correction of the starting oil quantity, reduces speed fluctuations, and improves the probability of successful engine starting.

[0093] After the engine is started successfully, the electronic control unit starts the fuel limiting unit, which limits the fuel growth rate to the speed growth rate, so that the engine can steadily enter the slow speed state.

[0094] It can be seen that the present invention helps the micro turbojet engine to start quickly, quickly enter the slow-speed state, and improve the starting success rate; in the throttle process from the slow-speed state to the rated speed, the speed response is fast and the speed fluctuation is small; the temperature of the nozzle is always controlled within a safe range to prevent the engine turbine from overheating.

[0095] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made within the spirit and principles of the present invention, as well as improvements to the control method and control system of the same micro-turbine engine, should be included in the scope of protection of the present invention.

Claims

1. A control method for a micro-turbine engine, characterized in that: The following steps are involved: S1. Start the engine, the starting oil volume = the initial starting oil volume, and output the initial oil supply PWM signal; S2, obtaining the engine speed increase rate dn; S3, determining whether the speed increase change rate dn is greater than the preset change rate D; If it is greater than, the starting oil volume is reduced according to the preset oil reduction amount, and the corresponding corrected oil supply PWM signal is output, and then S2 is executed; if it is not greater than, the current starting oil volume remains unchanged, and the corresponding current oil supply PWM signal is output; S5. Obtain fuel growth rate and speed growth rate; S6. Determine whether the fuel growth rate is less than the speed growth rate; S7. If it is less than, the current fuel supply PWM signal remains unchanged; if it is not less than, the fuel growth rate = the limited fuel growth rate, and the corresponding limited fuel supply PWM signal is output; The S4 is specifically: If it is greater than, according to the speed increase rate dn, the corresponding preset oil reduction amount is called, the corresponding corrected oil supply PWM signal is output, and then S2 is executed; The following steps are also included: S8, obtaining the actual engine speed, target speed, and feedforward fuel supply PWM signal; S9. Using an incremental PID speed regulator, outputting a corresponding first fuel supply PWM signal based on the actual speed, the target speed, and the feedforward fuel supply PWM signal; S10. Control the oil pump according to the first oil supply PWM signal to stabilize the engine speed.

2. The micro-turbine engine control method according to claim 1, characterized in that: After S9, the following steps are also included: determining whether the first fuel supply PWM signal exceeds a preset amplitude; If exceeded, it enters over-temperature protection mode; Get the nozzle temperature T; Determine whether the nozzle temperature T is greater than the preset Tmax-ΔT; If it is greater than, the over-temperature protection module is triggered, and the oil reduction amount ΔQ is calculated using the formula ΔQ = X1*[T-(Tmax-ΔT)]. Then, the corrected starting oil amount Q is calculated using the formula Q = Q-ΔQ. According to the corrected starting oil amount Q, the corresponding second oil supply PWM signal is output; If it is not greater than, exit the over-temperature protection; S10. Control the oil pump according to the second oil supply PWM signal to stabilize the engine speed.

3. The micro-turbine engine control method according to claim 2, characterized in that: The following steps are also included: Determine whether the nozzle temperature T is greater than the preset Tmax; If it is greater, use the formula ΔQ = X2*(T-Tmax) to calculate the oil reduction amount ΔQ; Then, the formula Q=Q-ΔQ is used to calculate the corrected starting oil quantity Q, and the corresponding second oil supply PWM signal is output according to the corrected starting oil quantity Q; If it is not greater than, exit the over-temperature protection.

4. The micro-turbine engine control method according to claim 3, characterized in that: The following steps are also included: Determine whether the nozzle temperature T is greater than the preset Tmax+ΔT; If it is greater than, the over-temperature protection module is triggered and the fuel reduction amount ΔQ is calculated using the formula ΔQ=X3*[T-(Tmax+ΔT)]; Then, the formula Q=Q-ΔQ is used to calculate the corrected starting oil quantity Q, and the corresponding second oil supply PWM signal is output according to the corrected starting oil quantity Q; If it is not greater than, exit the over-temperature protection.

5. The micro-turbine engine control method according to any one of claims 1 to 4, characterized in that: The feedforward fuel supply PWM signal is obtained from a preset second curve diagram, which is preset according to the engine speed and the fuel supply PWM signal.

6. A control system for a micro turbine engine, characterized in that: The system includes an electronic control unit and an oil pump, an engine, a speed sensor, a starting oil quantity correction unit and a fuel limit unit electrically connected to the electronic control unit respectively; The speed sensor is used to collect the speed of the engine and transmit it to the electronic control unit; The starting fuel quantity correction unit is used to obtain the engine speed increase change rate dn, and then determine whether the speed increase change rate dn is greater than a preset change rate D; if it is greater, the starting fuel quantity is gradually reduced according to the preset fuel reduction amount, and a corresponding corrected fuel supply PWM signal is output to the electronic control unit, and the judgment is repeated until it is no greater; if it is not greater, the current starting fuel quantity remains unchanged, and the corresponding current fuel supply PWM signal is output to the electronic control unit; The fuel limiting unit is used to obtain the fuel growth rate and the speed growth rate, and then determine whether the fuel growth rate is less than the speed growth rate; if so, output the current fuel supply PWM signal to the electronic control unit; if not, the fuel growth rate = the limited fuel growth rate, and output the corresponding limited fuel supply PWM signal to the electronic control unit; The electronic control unit controls the oil pump according to the received oil supply PWM signal to control the engine speed; The system also includes a PID speed regulation unit, which includes an incremental PID speed regulator. The incremental PID speed regulator outputs a corresponding first oil supply PWM signal to the electronic control unit based on the actual speed, the target speed and the feedforward oil supply PWM signal. The electronic control unit controls the oil pump based on the received first oil supply PWM signal.

7. The micro-turbine engine control system according to claim 6, characterized in that: The system also includes an over-temperature protection unit, which is used to generate and transmit a corresponding second oil supply PWM signal to the electronic control unit according to the nozzle temperature T when the first oil supply PWM signal exceeds a preset amplitude. The electronic control unit adjusts the oil pump according to the received second oil supply PWM signal.

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