A ship hybrid power intelligent power generation unit cooperative control method

Abstract

The application aims to provide a ship hybrid power intelligent power generation unit cooperative control method, comprising an ammonia fuel engine and a three-phase permanent magnet synchronous motor, the ammonia fuel engine adopts throttle torque control, and the three-phase permanent magnet synchronous motor adopts speed control; the ammonia fuel engine is provided with a pre-preparation feedforward ammonia injection amount dynamic correction lookup table, a speed regulation ammonia injection amount MAP lookup table, an idle ammonia injection amount MAP lookup table and a smoke limit lookup table, the smoke limit lookup table takes boost pressure, boost temperature and air flow as input, the idle ammonia injection amount MAP lookup table takes cooling water temperature and estimated speed as input, the speed regulation ammonia injection amount MAP lookup table takes pedal position and estimated speed as input, and the feedforward ammonia injection amount dynamic correction lookup table takes estimated speed and estimated torque as input, so as to comprehensively optimize ammonia injection amount and control ammonia engine speed. The application can realize cooperative control of the ammonia fuel engine and the permanent magnet motor, reduce the use of sensors, improve system control performance and be applied to mass production.

Description

Technical Field

[0001] The present invention relates to a ship control method, specifically a ship hybrid power control method. Background Technology

[0002] Currently, marine power systems, which are mainly based on diesel engines, have the disadvantages of high pollution, low energy consumption, and high carbon emissions. Therefore, there is an urgent need to find a low-carbon and efficient power system to meet the increasingly stringent carbon reduction requirements and adapt to the future goals of low-carbonization and even zero carbon.

[0003] Ammonia fuel, as a clean fuel, is widely used in the chemical industry. As a zero-carbon fuel, it has also attracted increasing attention in the marine propulsion field in recent years. Although the concept of ammonia fuel engines has been proposed in the shipbuilding industry, mature products are still lacking due to technological limitations. On the one hand, there is a lack of comprehensive research on the performance of ammonia fuel engines; on the other hand, there is no clear technical solution for matching ammonia fuel engines with appropriate power systems. Therefore, the research and development of ammonia fuel engines is still in its initial stage, and hybrid power systems for ammonia fuel engines are currently a technological void.

[0004] Marine hybrid power systems combine the advantages of traditional internal combustion engine propulsion and pure electric propulsion. Hybrid systems offer significant advantages in overall energy efficiency, energy conservation and emission reduction, and vibration and noise reduction. Furthermore, compared to pure electric propulsion systems, they can achieve long driving ranges with smaller capacity batteries at a lower cost. Hybrid systems based on ammonia fuel engines can meet the requirements of zero-carbon power while mitigating the low efficiency and cold-start difficulties of ammonia fuel engines. The introduction of an electric motor can also improve the dynamic characteristics of ammonia fuel engines, achieving complementary advantages from multiple power sources. Hybrid systems based on ammonia fuel engines will become one of the best power forms for future zero-carbon power.

[0005] Currently, power generation units based on ammonia fuel engines simply mechanically couple the ammonia fuel engine and the electric motor, with each controller operating independently. This leads to uncoordinated control and wasted hardware. Furthermore, the entire power generation unit requires coordinated control to maximize its advantages. Summary of the Invention

[0006] The purpose of this invention is to provide a collaborative control method for intelligent hybrid power generation units in ships that overcomes the shortcomings of poor control performance caused by separate control of the engine and motor in traditional hybrid power generation units.

[0007] The objective of this invention is achieved as follows:

[0008] This invention discloses a collaborative control method for a ship hybrid intelligent power generation unit, characterized by: including an ammonia fuel engine and a three-phase permanent magnet synchronous motor; the ammonia fuel engine employs throttle torque control, and the three-phase permanent magnet synchronous motor employs speed control; the ammonia fuel engine includes pre-prepared feedforward ammonia injection quantity dynamic correction lookup table, speed-regulating ammonia injection quantity MAP lookup table, no-load ammonia injection quantity MAP lookup table, and smoke limit lookup table. The smoke limit lookup table uses boost pressure, boost temperature, and air flow as inputs; the no-load ammonia injection quantity MAP lookup table uses cooling water temperature and estimated speed as inputs; the speed-regulating ammonia injection quantity MAP lookup table uses pedal position and estimated speed as inputs; and the feedforward ammonia injection quantity dynamic correction lookup table uses estimated speed and estimated torque as inputs, thereby comprehensively optimizing the ammonia injection quantity to control the ammonia engine speed.

[0009] The present invention may also include:

[0010] 1. The speed control of a three-phase permanent magnet synchronous motor includes: an active flux observer to estimate the motor angle, a speed observer to observe the speed, and a dual-loop control of the motor speed and current using a speed PID loop and a current PID loop.

[0011] The expression for the active flux observer is:

[0012]

[0013]

[0014] ψ CM =K active ψ2|ψ2| -1

[0015] ψ VM =∫u-Ri+w v dt+L q i

[0016]

[0017]

[0018] The expression for the rotational speed observer is:

[0019]

[0020]

[0021]

[0022]

[0023] Where: K active For active flux; L d It is a direct-axis inductor; L qFor axial inductance; r req For virtual resistance; i d For stator direct-axis current; i q For stator quadrature-axis current; K E ψ1 is the stator flux linkage; u is the stator voltage; i is the stator current; w v For interference; k p k is the scaling factor for the flux linkage observer. i ψ is the integral coefficient; ψ2 is the active flux vector; ψ CM For the current model, the corresponding magnetic flux linkage is ψ. VM For the magnetic flux corresponding to the voltage model; Quadrature axis current estimate; n is the estimated motor speed. pp J is the number of pole pairs of the motor; s This refers to the moment of inertia of the motor. K is the estimated load torque value. p K is the proportional coefficient of the speed observer; i K is the integral coefficient; d U' is the differential coefficient; q ε is the quadrature-axis voltage; ε is the error operator.

[0024] 2. The conversion relationship between the estimated speed of the ammonia fuel engine and the estimated speed of the three-phase permanent magnet synchronous motor is as follows:

[0025]

[0026] Where: n e For ammonia fuel engine speed; θ e This refers to the crankshaft rotation angle; Estimate the angle of the motor rotor; T e For engine torque; η m This refers to the motor efficiency.

[0027] 3. Sample the three-phase currents of the three-phase permanent magnet synchronous motor and the given reference voltage, and convert them into the corresponding α and β axis currents and voltages in the Clark coordinate system. Using the α and β axis currents and the reference voltage as inputs, calculate the estimated value of the motor rotor angle through the active flux linkage observer expression. Using the estimated value of the motor rotor angle as input, perform Park transformation on the stator currents under the α and β axes to obtain the stator current under the dq axis. Using the stator current under the dq axis as input and the given reference voltage under the dq axis as input, calculate the estimated motor speed and the estimated load torque through the speed observer expression. The difference between the estimated motor speed and the given speed is fed into the speed PID loop. The speed PID loop outputs the reference dq axis current, and the difference between it and the actual stator dq axis current fed back by the motor passes through the current PID loop to output the given reference voltage under the α and β axes. Finally, the SVPWM waveform generation module sends a signal to the inverter to control the motor stator current to control the speed.

[0028] 4. The estimated motor speed and estimated motor load torque obtained from motor control are processed by formula... The process is converted into ammonia engine speed and load torque. The ammonia engine speed and torque are used as inputs to query the dynamic correction table for feedforward ammonia injection quantity to obtain the feedforward value. The pedal position obtained from the required torque, together with the engine speed, is used as inputs to query the speed-regulating ammonia injection quantity MAP table as the increment. The coolant temperature and engine speed are used as inputs to query the no-load ammonia injection quantity MAP table to obtain the no-load ammonia injection quantity. Boost pressure, boost temperature, and airflow are used as inputs to query the smoke limit as the ammonia injection quantity limit. Finally, the feedforward ammonia injection quantity, speed-regulating ammonia injection quantity, and no-load ammonia injection quantity are accumulated, and the smoke limit is used as the limit. A MIN / MAX strategy is employed to output the ammonia injection quantity required by the engine, thus completing the engine throttle torque control.

[0029] The advantages of this invention are:

[0030] 1. This invention proposes a hardware design scheme and collaborative control method for a marine hybrid intelligent power generation unit. The hardware design eliminates the crankshaft sensor of the ammonia fuel engine, instead aligning the center line of the wide-toothed signal disk at the crankshaft flywheel end with the spatial axis of the three-phase permanent magnet motor in the A-direction. This design allows for the calculation of the crankshaft angle of the ammonia engine by acquiring the position of the motor rotor, without the need for complex conversions. This saves on sensor hardware costs and significantly reduces the signal processing load on the engine controller, saving computational space.

[0031] 2. The collaborative control strategy of the hybrid intelligent power generation unit adopts engine throttle torque control and motor speed control, which fully considers the dynamic characteristics of both. That is, it takes advantage of the motor's fast dynamic response to quickly reach a high speed state, while the engine uses throttle control to load, which can make the engine work in the high speed range as much as possible, resulting in better engine economy.

[0032] 3. The three-phase permanent magnet synchronous motor adopts a sensorless control method, using active flux to observe the rotor angle and an extended state observer to estimate the motor speed and torque. The estimated torque of the motor can be used as a feedforward input for the ammonia fuel engine, which greatly improves the dynamic response of the ammonia engine. At the same time, the sensorless speed control method also saves the motor speed sensor, which saves two sensors for the entire power unit and reduces hardware costs.

[0033] 4. The motor adopts speed control, which can directly use the speed loop to drag the ammonia fuel engine to idle speed during the start-up phase, without switching control modes during the power output phase, thus reducing the control difficulty.

[0034] 5. Another advantage of this invention is that it uses an ammonia fuel engine, which is clean and low-carbon, in line with the development direction of green ships. Attached Figure Description

[0035] Fig. 1 This is a schematic diagram of the control structure of the present invention;

[0036] Fig. 2 This is a hardware structure layout diagram of the present invention. Detailed Implementation

[0037] The invention will now be described in more detail with reference to the accompanying drawings:

[0038] Combination Figs. 1-2 A hardware design scheme and collaborative control strategy for a ship hybrid intelligent power generation unit includes: a lookup table 1 for feedforward ammonia injection quantity dynamic correction, a lookup table 2 for speed regulation ammonia injection quantity MAP, a lookup table 3 for no-load ammonia injection quantity MAP, and a lookup table 4 for smoke limit in the control of an ammonia fuel engine; and a speed observer 5, a speed PID 6, a current PID 7, an active flux observer 8, and an SVPWM module 9 in the control of a three-phase permanent magnet synchronous motor.

[0039] A hardware design scheme and collaborative control strategy for a ship hybrid intelligent power generation unit includes an integrated ammonia fuel engine, a three-phase permanent magnet synchronous motor, a diesel engine control method, and a three-phase permanent magnet synchronous motor control method.

[0040] In the intelligent power generation unit, the center line of the shaft corresponding to the wide tooth gap of the flywheel signal disk in the ammonia fuel engine is aligned with the spatial position axis of phase A of the stator winding of the three-phase permanent magnet synchronous motor. At the same time, phase A is aligned with the direct axis in both the three-phase coordinate system and the quadrature-direct axis coordinate system. Meanwhile, the crankshaft sensor of the ammonia fuel engine is eliminated.

[0041] The ammonia engine uses throttle torque control, while the three-phase permanent magnet synchronous motor uses speed control.

[0042] The speed control of a three-phase permanent magnet synchronous motor includes an active flux observer to estimate the motor angle, a speed observer to observe the speed, and a dual-loop control of the motor speed and current using a speed PID loop and a current PID loop.

[0043] The expression for the active flux observer is:

[0044]

[0045]

[0046] ψ CM =K active Ψ2|Ψ2| -1 (3)

[0047] Ψ VM =∫u-Ri+w v dt+L q i (4)

[0048]

[0049]

[0050] The expression for the rotational speed observer is:

[0051]

[0052]

[0053]

[0054]

[0055] Where: K active For active flux; L d It is a direct-axis inductor; L q For axial inductance; r req For virtual resistance; i d For stator direct-axis current; i q For stator quadrature-axis current; K E ψ1 is the stator flux linkage; u is the stator voltage; i is the stator current; w v For interference; k p k is the scaling factor for the flux linkage observer. i ψ is the integral coefficient; ψ2 is the active flux vector; ψ CM For the current model, the corresponding magnetic flux linkage is ψ. VM For the magnetic flux corresponding to the voltage model; Quadrature axis current estimate; n is the estimated motor speed. pp J is the number of pole pairs of the motor;s This refers to the moment of inertia of the motor. K is the estimated load torque value. p K is the proportional coefficient of the speed observer; i K is the integral coefficient; d U' is the differential coefficient; q ε is the quadrature-axis voltage; ε is the error operator;

[0056] The throttle torque control method used in ammonia fuel engines includes: using a smoke limit lookup table with boost pressure, boost temperature, and air flow as inputs; a no-load ammonia injection quantity MAP lookup table with coolant temperature and estimated speed as inputs; a speed-regulating ammonia injection quantity MAP lookup table with pedal position and estimated speed as inputs; and a feedforward ammonia injection quantity dynamic correction lookup table with estimated speed and estimated torque as inputs to comprehensively optimize the ammonia injection quantity and thus control the ammonia engine speed.

[0057] A hardware design scheme and collaborative control strategy for a marine hybrid intelligent power generation unit, characterized in that the conversion relationship between the estimated speed of the ammonia fuel engine and the estimated speed of the motor is as follows:

[0058]

[0059] Where: n e For ammonia fuel engine speed; θ e This refers to the crankshaft rotation angle; Estimate the angle of the motor rotor; T e For engine torque; η m This refers to the motor efficiency.

[0060] The detailed control process is as follows: First, the three-phase current of the three-phase permanent magnet synchronous motor and the given reference voltage are sampled and converted into the corresponding α and β axis currents and voltages in the Clark coordinate system. Using the α and β axis currents and the reference voltage as inputs, the estimated value of the motor rotor angle is calculated by the active flux linkage observer 8 using equations (1)-(6). Using the estimated value of the motor rotor angle as input, the stator current under the α and β axes is transformed by Park to obtain the stator current under the dq axis. Using the stator current under the dq axis as input and the given reference voltage under the dq axis as input, the estimated motor speed and the estimated load torque are calculated by the speed observer 5 using equations (7)-(10). The difference between the estimated motor speed and the given speed is entered into the speed PID loop 6. The speed PID loop 6 outputs the reference dq axis current and the difference between the actual stator dq axis current fed back by the motor. After passing through the current PID loop 7, the given reference voltage under the α and β axes is output. Finally, the SVPWM waveform generation module 9 sends a signal to the inverter 10 to control the motor stator current to control the speed.

[0061] The estimated motor speed and load torque obtained from motor control are converted into ammonia engine speed and load torque using equation (11). The ammonia engine speed and torque are used as inputs to query the dynamic correction table 1 for feedforward ammonia injection quantity to obtain the feedforward value. The pedal position obtained from the required torque, together with the engine speed, is used as inputs to query the speed-regulating ammonia injection quantity MAP table 2 as the increment. The coolant temperature and engine speed are used as inputs to query the no-load ammonia injection quantity MAP table to obtain the no-load ammonia injection quantity. The boost pressure, boost temperature, and airflow are used as inputs to query the smoke limit as the ammonia injection quantity limit. Finally, the feedforward ammonia injection quantity, speed-regulating ammonia injection quantity, and no-load ammonia injection quantity are accumulated, and the MIN / MAX strategy is used to output the required ammonia injection quantity for the engine, thus completing the engine throttle torque control.

[0062] The crankshaft angle signal required for other engine controls can be given by formula (11) and used to determine the top dead center, cylinder, and fuel injection timing.

Claims

1. A collaborative control method for a ship hybrid power intelligent power generation unit, characterized by: This includes an ammonia fuel engine and a three-phase permanent magnet synchronous motor. The ammonia fuel engine uses throttle torque control, while the three-phase permanent magnet synchronous motor uses speed control. The ammonia fuel engine uses tables for pre-feedback ammonia injection quantity dynamic correction, speed-regulating ammonia injection quantity MAP, no-load ammonia injection quantity MAP, and smoke limit. The smoke limit table uses boost pressure, boost temperature, and air flow as inputs. The no-load ammonia injection quantity MAP table uses coolant temperature and estimated speed as inputs. The speed-regulating ammonia injection quantity MAP table uses pedal position and estimated speed as inputs. The feedforward ammonia injection quantity dynamic correction table uses estimated speed and estimated torque as inputs, thereby comprehensively optimizing the ammonia injection quantity to control the ammonia engine speed. The signal disk at the crankshaft flywheel end is arranged with its wide tooth centerline aligned with the spatial axis of the three-phase permanent magnet motor in direction A. The speed control of a three-phase permanent magnet synchronous motor includes: an active flux observer to estimate the motor angle, a speed observer to observe the speed, and a dual-loop control of the motor speed and current using a speed PID loop and a current PID loop. The expression for the active flux observer is: ； ； ； ； ； ； in, Active flux; It is a direct-axis inductor; Axial inductance; For virtual resistance; This refers to the stator direct-axis current. For permanent magnet flux linkage; For stator flux linkage; Stator voltage; Stator current; This is the interference quantity; This is the scaling factor for the magnetic flux observer; The integral coefficient; The active flux linkage vector; For the current model, the corresponding magnetic flux linkage; This represents the magnetic flux linkage corresponding to the voltage model.

2. The method for coordinated control of a ship hybrid power intelligent power generation unit according to claim 1, characterized in that: The expression for the rotational speed observer is: ； ； ； ； in: This refers to the stator quadrature-axis current; Quadrature axis current estimate; This is an estimated value for the motor speed; This represents the number of pole pairs of the motor. This refers to the moment of inertia of the motor. This is an estimated value for the load torque; This is the proportional coefficient for the speed observer; The integral coefficient; These are the differential coefficients; It is the quadrature axis voltage; This is the error operator.

3. The method for coordinated control of a ship hybrid power intelligent power generation unit according to claim 1, characterized in that: The conversion relationship between the estimated speed of an ammonia fuel engine and the estimated speed of a three-phase permanent magnet synchronous motor is as follows: ； in: This refers to the rotational speed of an ammonia fuel engine. This refers to the crankshaft rotation angle; Estimate the angle for the motor rotor; This refers to engine torque; This refers to the motor efficiency.

4. The method for coordinated control of a ship hybrid power intelligent power generation unit according to claim 2, characterized in that: The three-phase currents of the sampled three-phase permanent magnet synchronous motor and the given reference voltage are converted into their corresponding values ​​in the Clark coordinate system. , shaft current and voltage, , The shaft current and reference voltage are used as inputs, and the estimated value of the motor rotor angle is calculated through the active flux observer expression. Using the estimated value of the motor rotor angle as input pair , The stator current under the dq axis is obtained by performing the Park transformation on the stator current under the dq axis. Using the stator current along the dq axis as input and the given reference voltage along the dq axis as input, the estimated motor speed and load torque are calculated using the speed observer expression. The difference between the estimated motor speed and the given speed is fed into the speed PID loop. The difference between the speed PID loop output reference dq axis current and the actual stator dq axis current fed back by the motor is fed into the current PID loop and then outputs the given speed. , The shaft reference voltage is then sent to the inverter via the SVPWM waveform generator to control the motor stator current and thus the speed.

5. The method for coordinated control of a ship hybrid power intelligent power generation unit according to claim 3, characterized in that: The estimated motor speed and estimated motor load torque obtained from motor control are processed by the formula The process is converted into ammonia engine speed and load torque. The ammonia engine speed and torque are used as inputs to query the dynamic correction table for feedforward ammonia injection quantity to obtain the feedforward value. The pedal position obtained from the required torque, together with the engine speed, is used as inputs to query the speed-regulating ammonia injection quantity MAP table as the increment. The coolant temperature and engine speed are used as inputs to query the no-load ammonia injection quantity MAP table to obtain the no-load ammonia injection quantity. Boost pressure, boost temperature, and airflow are used as inputs to query the smoke limit as the ammonia injection quantity limit. Finally, the feedforward ammonia injection quantity, speed-regulating ammonia injection quantity, and no-load ammonia injection quantity are accumulated, and the smoke limit is used as the limit. A MIN / MAX strategy is employed to output the ammonia injection quantity required by the engine, thus completing the engine throttle torque control.

Images