Hybrid excitation controllable power generation system based on temperature detection and control method thereof

Abstract

The application discloses a hybrid excitation controllable power generation system based on temperature detection and a control method thereof, and relates to the technical field of power generation, in particular to a hybrid excitation controllable power generation system based on temperature detection and a control method thereof. The hybrid excitation controllable power generation system comprises a hybrid excitation motor, a power generation controller, switches K1-K2, the hybrid excitation motor comprises an electrically excited synchronous reluctance motor and a permanent magnet synchronous motor arranged coaxially, and the power generation controller comprises a rectification power circuit, an excitation power circuit, a power generation control unit, current sensors Ha-Hc, a voltage sensor, a temperature sensor one, a temperature sensor two and a position sensor for detecting the rotor position of the hybrid excitation motor. The power generation control unit determines the control mode of the hybrid excitation power distribution controllable power generation system according to the electrically excited synchronous reluctance motor stator winding temperature signal and the permanent magnet synchronous motor stator winding temperature signal, and outputs switch signals to control the closing or opening of the switches. The application effectively detects short-circuit faults and avoids demagnetization of permanent magnets caused by high temperature, and realizes the minimum copper loss of the power generation system under the premise of safe and reliable operation of the power generation system.

Description

Technical Field

[0001] This invention relates to power generation systems, and more particularly to a hybrid excitation controllable power generation system based on temperature detection and its control method. Background Technology

[0002] In the current development of aviation technology, due to the continuous increase in electrical power consumption and the proliferation of electrical equipment and electric actuation mechanisms, the requirements for reliability, maintainability, operability, and fuel economy are becoming increasingly stringent. Multi-electric / fully electric aircraft have become the development trend for both civil and military aircraft and helicopters. As the core component for completing electromechanical energy conversion, the selection of the starter generator is of great significance to the performance of electric / fully electric aircraft.

[0003] Permanent magnet synchronous motors (PMSMs) are widely used in industry, shipbuilding, and electric vehicles due to their simple structure, high power density, and high efficiency. However, their application in aviation power systems is limited, mainly because the air gap magnetic field of PMSMs is difficult to adjust, and demagnetization during faults is challenging. Hybrid excitation motors employ a parallel magnetic circuit structure, decoupling the permanent magnet and electrically excited magnetic circuits. This improves excitation efficiency while reducing the risk of irreversible demagnetization of the permanent magnets. Furthermore, in this hybrid excitation motor, the permanent magnets are located in the rotor while the excitation windings are located in the stator. The motor structure is simple, inheriting the inherent brushless advantage of reluctance motors. The simple rotor structure is suitable for high-speed operation, making it of significant research value and application advantages in aviation power systems.

[0004] When hybrid excitation motors are used in aviation power systems, regulated output over a wide speed range is required. Due to the differences in characteristics between permanent magnet synchronous motors (PMSMs) and electrically excited synchronous reluctance motors (EMS), the armature responses of the two motors differ under load. The EMS, with its high impedance characteristics, exhibits more severe armature response, leading to phase shift in the hybrid excitation motor and consequently, the generation and flow of reactive power. In power generation systems employing uncontrolled rectification, the constraint of a power factor of 1 for the entire motor results in equal reactive power generation between the PMSM and the reluctance motor, leading to significant reactive power flow in the hybrid excitation motor and inhibiting the effective output of the high-power-density PMSM. Especially at low speeds, the large current angle and severe armature response significantly increase the required excitation power, increasing copper losses and reducing the system's efficiency.

[0005] Therefore, the above problems urgently need to be solved. Summary of the Invention

[0006] Purpose of the invention: The first purpose of this invention is to provide a temperature-detection-based hybrid excitation controllable power generation system. By detecting the temperature of the permanent magnet synchronous motor and the electrically excited synchronous reluctance motor in the hybrid excitation motor, the control mode can be determined. This can effectively detect short-circuit faults and avoid high-temperature demagnetization of permanent magnets, thereby minimizing copper loss in the power generation system while ensuring safe and reliable operation.

[0007] A second objective of this invention is to provide a control method for the temperature-detection-based hybrid excitation controllable power generation system.

[0008] Technical solution: To achieve the above objectives, this invention discloses a temperature-detection-based hybrid excitation controllable power generation system, comprising a hybrid excitation motor, a power generation controller, switch K1, and switch K2.

[0009] The hybrid excitation motor includes an electrically excited synchronous reluctance motor and a permanent magnet synchronous motor arranged coaxially, and the generator controller includes a rectifier power circuit, an excitation power circuit, a generator control unit, and a current sensor H. a Current sensor H b Current sensor H c Voltage sensor H f Temperature sensor 1, temperature sensor 2, and a position sensor for detecting the rotor position of the hybrid excitation motor;

[0010] The output terminal of the armature winding of the electrically excited synchronous reluctance motor is connected to the input terminal of the permanent magnet synchronous motor. The output terminal of the permanent magnet synchronous motor is connected to the input terminal of the rectifier power circuit. The positive output terminal of the rectifier power circuit is connected to the first contact of switch K2, the second contact of switch K2 is connected to the positive input terminal of the load, and the negative output terminal of the rectifier power circuit is connected to the negative input terminal of the load. The positive input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the first contact of switch K1, the second contact of switch K1 is connected to the positive output terminal of the excitation power circuit, and the negative input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the negative output terminal of the excitation power circuit.

[0011] Current sensor H a Current sensor H b Current sensor H c The measured three-phase armature winding current i of the hybrid excitation motor a i b i c Transmitted to the power generation control unit, voltage sensor H f The voltage signal u at the output of the rectifier power circuit obtained by detection o The rotor position signal of the hybrid excitation motor, detected by the position sensor, is transmitted to the power generation control unit; the stator winding temperature signal T of the electrically excited synchronous reluctance motor, detected by temperature sensor one and temperature sensor two respectively, is transmitted to the power generation control unit.a Temperature signal T of the stator winding of the permanent magnet synchronous motor b The signal is transmitted to the power generation control unit; the power generation control unit then uses the stator winding temperature signal T of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b Determine the control mode of the hybrid excitation power distribution controllable generator system, and the output switching signal S. K1 S K2 Control the closing or opening of switches K1 and K2 respectively.

[0012] The electrically excited synchronous reluctance motor includes an electrically excited synchronous reluctance motor stator core, an electrically excited synchronous reluctance motor rotor core, an electrically excited synchronous reluctance motor excitation winding, and an electrically excited synchronous reluctance motor armature winding. The electrically excited synchronous reluctance motor stator core includes several stator poles evenly distributed, and the electrically excited synchronous reluctance motor rotor core includes several rotor poles evenly distributed. The electrically excited synchronous reluctance motor excitation winding and the electrically excited synchronous reluctance motor armature winding are both wound on the stator poles of the electrically excited synchronous reluctance motor stator core.

[0013] Preferably, the permanent magnet synchronous motor includes a permanent magnet synchronous motor stator core, a permanent magnet synchronous motor rotor core, a permanent magnet synchronous motor armature winding, and a permanent magnet. The permanent magnet synchronous motor stator core includes several stator poles evenly distributed, the permanent magnet adopts a surface-mount structure, and the permanent magnet synchronous motor is a three-phase 10-pole structure.

[0014] Furthermore, the rectifier power circuit includes power switching transistors T1, T2, T3, T4, T5, and T6, diodes D1, D2, D3, D4, D5, and D6, and capacitor C1. The emitter of power switching transistor T1 is connected to the anode of diode D1, and the collector of power switching transistor T1 is connected to the cathode of diode D1. The emitter of power switching transistor T2 is connected to the anode of diode D2, and the collector of power switching transistor T2 is connected to the cathode of diode D2. The emitter of power switching transistor T3 is connected to the anode of diode D3, and the collector of power switching transistor T3 is connected to the cathode of diode D3. The emitter of power switching transistor T4 is connected to the anode of diode D4, and the collector of power switching transistor T4 is connected to the cathode of diode D4. The emitter of power switching transistor T5 is connected to the anode of diode D5, and the collector of power switching transistor T5 is connected to the cathode of diode D5. The emitter of power switch T6 is connected to the anode of diode D6, and the collector of power switch T6 is connected to the cathode of diode D6. The emitter of power switch T1 is connected to the collector of power switch T4, the emitter of power switch T3 is connected to the collector of power switch T6, and the emitter of power switch T5 is connected to the collector of power switch T2. The collectors of power switch T1, T3, and T5 form the positive output terminal of the rectifier power circuit. The emitters of power switch T4, T6, and T2 form the negative output terminal of the rectifier power circuit. The emitters of power switch T1, T3, and T5 form the input terminals of the rectifier power circuit. The rectified power output terminal passes through capacitor C1, and the generator control unit outputs control signals PWMT1~T6 to control the chopping of power switches T1~T6 in the rectifier power circuit.

[0015] Furthermore, the excitation power circuit includes power switching transistors T7 and T8, diodes D7 and D8, and capacitor C2. The emitter of power switching transistor T7 is connected to the cathode of diode D7, forming the positive output terminal of the excitation power circuit. The collector of power switching transistor T7 is connected to the cathode of diode D8, forming the positive input terminal of the excitation power circuit. The emitter of power switching transistor T8 is connected to the anode of diode D7, forming the negative output terminal of the excitation power circuit. The collector of power switching transistor T8 is connected to the anode of diode T8, forming the negative input terminal of the excitation power circuit. The input terminal of the excitation power circuit passes through capacitor C2, and the generator control unit outputs the control signal PWM. T7～T8 The power switching transistors T7 and T8 in the excitation power control circuit are used for chopping.

[0016] Preferably, the hybrid excitation motor further includes a housing, an end cover adapted to the housing, and a shaft located inside the housing for housing the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor.

[0017] Furthermore, the power generation control unit is connected to an external battery, and the power generation control unit communicates with the external data bus.

[0018] Furthermore, the position sensor is connected to the power generation control unit through a decoder and a speed calculation unit. The rotor position signal of the hybrid excitation motor detected by the position sensor is transmitted to the power generation control unit after the speed is calculated by the decoder and the speed calculation unit.

[0019] The present invention discloses a control method for a hybrid excitation controllable power generation system based on temperature detection, comprising the following steps:

[0020] The current signal of the armature winding of the hybrid excitation motor is obtained by detecting the current sensor, the output voltage signal of the rectified power armature is obtained by the voltage sensor, the rotor position signal of the hybrid excitation motor is obtained by detecting the position sensor, and the winding temperature signals of the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor are obtained by the temperature sensor, and then sent to the power generation control unit.

[0021] The power generation control unit determines the control mode of the hybrid excitation power distribution controllable power generation system based on the stator winding temperature signals of the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor, and controls the closing or opening of switches K1 and K2 respectively based on the output switch signals.

[0022] The specific methods for determining the control mode of the hybrid excitation power distribution controllable power generation system and controlling the closing or opening of switches K1 and K2 with output switch signals are as follows:

[0023] The system receives the start signal from the data bus, completes the self-test procedure, and the power generation control unit detects the speed of the hybrid excitation motor, waiting for the speed n to reach the speed range required for system operation, i.e., n... min ≤n≤n max When switch K1 is closed, the generator controller performs power generation control and compares the stator winding temperature T of the electrically excited synchronous reluctance motor. a With set temperature T a * And the stator winding temperature T of the permanent magnet synchronous motor b With a given temperature T b * ;

[0024] When T a ≤T a *When the system enters control mode one, the control objective of control mode one is to minimize the copper loss of the power generation system under constant voltage operation, and to establish the minimum excitation current I required for constant voltage output of the hybrid excitation motor under different operating conditions. f With minimum weak magnetic current I d The lookup table is stored in the generator control unit; based on the load and the speed signal received by the generator control unit, the minimum excitation current I at this time is obtained. f * With the minimum d-axis weak magnetic current I d * The generator control unit adjusts the duty cycle of power switches T7 and T8 in the excitation power circuit to adjust the current of the excitation winding to I. f * The generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β PWM is generated through SVPWM control. T1～T6 The signal controls the switching on and off of the six power switching transistors T1 to T6 in the rectifier power circuit to maintain constant voltage output with minimum copper loss in the power generation system;

[0025] If T a >T a * Then determine T b With T b * The relationship, if T b ≤T b * Entering control mode two, the control objective of control mode two is to reduce the stator winding temperature of the permanent magnet synchronous motor to a given value T under constant pressure operation. b * The following describes the minimum excitation current I in control mode one. f Based on this, the excitation current is increased, and the generator control unit searches for the minimum field weakening current I based on the increased excitation current. dThe generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, the d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β Through SVPWM control, PWMT1 to T6 signals are generated to control the switching on and off of the six power switches T1 to T6 in the rectifier power circuit. This is done when the temperature of the stator winding of the permanent magnet synchronous motor drops to a given value T. b * The following measures aim to minimize copper losses under the premise of constant voltage output;

[0026] If T b >T b * This indicates that the load has exceeded the operating range of the power generation system. The power generation control unit issues an unloading command, disconnects switch K2, and disconnects switch K1.

[0027] Beneficial Effects: Compared with the prior art, the present invention has the following significant advantages: First, the hybrid excitation controllable power generation system of the present invention monitors the stator winding temperature of the permanent magnet synchronous motor and the electrically excited synchronous reluctance motor in real time, and switches the control mode according to the temperature. Based on the working requirements and the status of the two motors, it optimizes the power allocation under the premise of ensuring safe and stable operation. Second, the temperature detection of the hybrid excitation controllable power generation system of the present invention can simultaneously detect stator winding short-circuit faults, improving the reliability of the system. Finally, the parallel hybrid excitation controllable power generation system and its control method of the present invention can release the power output capacity of high power density permanent magnet synchronous motors, which is beneficial to improving the design difficulties of excitation mechanism in traditional hybrid excitation uncontrolled rectifier power generation systems in wide-speed power generation, thereby broadening the application speed range. Attached Figure Description

[0028] Figure 1 This is a system connection block diagram of the present invention;

[0029] Figure 2 This is a cross-sectional schematic diagram of the permanent magnet synchronous motor in this invention;

[0030] Figure 3 This is a cross-sectional schematic diagram of the electrically excited synchronous reluctance motor in this invention;

[0031] Figure 4 This is a schematic diagram of the cross-section of the hybrid excitation motor in this invention;

[0032] Figure 5This is a structural diagram of the rectifier power circuit in this invention;

[0033] Figure 6 This is a structural diagram of the excitation power circuit in this invention;

[0034] Figure 7 This is the control flowchart of the present invention. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0036] like Figure 1 As shown, the present invention provides a temperature-detection-based hybrid excitation controllable power generation system, which includes a hybrid excitation motor, a power generation controller, a switch K1, and a switch K2.

[0037] The hybrid excitation motor includes an electrically excited synchronous reluctance motor and a permanent magnet synchronous motor arranged coaxially. The generator controller includes a rectifier power circuit, an excitation power circuit, a generator control unit, a decoder, a speed calculation unit, and a current sensor H. a Current sensor H b Current sensor H c Voltage sensor H f Temperature sensor 1, temperature sensor 2, and a position sensor for detecting the rotor position of the hybrid excitation motor; the position sensor is connected to the power generation control unit via a decoder and a speed calculation unit.

[0038] One end of the armature winding of the electrically excited synchronous reluctance motor is connected in a star configuration. The output end of the armature winding of the electrically excited synchronous reluctance motor is connected to the input end of the permanent magnet synchronous motor. The output end of the permanent magnet synchronous motor is connected to the input end of the rectifier power circuit. The positive output terminal of the rectifier power circuit is connected to the first contact of switch K2, the second contact of switch K2 is connected to the positive input terminal of the load, and the negative output terminal of the rectifier power circuit is connected to the negative input terminal of the load. The positive input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the first contact of switch K1, the second contact of switch K1 is connected to the positive output terminal of the excitation power circuit, and the negative input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the negative output terminal of the excitation power circuit.

[0039] Current sensor H a Current sensor H b Current sensor H c The measured three-phase armature winding current i of the hybrid excitation motor a i b i c Transmitted to the power generation control unit, voltage sensor H f The voltage signal u at the output of the rectifier power circuit obtained by detection oThe rotor position signal of the hybrid excitation motor, detected by the position sensor, is transmitted to the power generation control unit. Specifically, the rotor position signal is processed by a decoder and a speed calculation unit to obtain the speed of the hybrid excitation motor, which is then transmitted to the power generation control unit. Temperature sensors one and two respectively detect the stator winding temperature signal T of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b The signal is transmitted to the power generation control unit; the power generation control unit then uses the stator winding temperature signal T of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b Determine the control mode of the hybrid excitation power distribution controllable generator system, and the output switching signal S. K1 S K2 Control the closing or opening of switches K1 and K2 respectively.

[0040] like Figure 2 As shown, the electrically excited synchronous reluctance motor includes an electrically excited synchronous reluctance motor stator core 1, an electrically excited synchronous reluctance motor rotor core 2, an electrically excited synchronous reluctance motor excitation winding 3, and an electrically excited synchronous reluctance motor armature winding 4. The electrically excited synchronous reluctance motor stator core 1 includes 12 stator poles evenly distributed, and the electrically excited synchronous reluctance motor rotor core includes 10 rotor poles evenly distributed. The electrically excited synchronous reluctance motor excitation winding 3 and the electrically excited synchronous reluctance motor armature winding 4 are both wound on the stator poles of the electrically excited synchronous reluctance motor stator core.

[0041] like Figure 3 As shown, the permanent magnet synchronous motor includes a permanent magnet synchronous motor stator core 5, a permanent magnet synchronous motor rotor core 6, a permanent magnet synchronous motor armature winding 7, and a permanent magnet 8. The permanent magnet synchronous motor stator core 5 includes 24 stator poles evenly distributed. The permanent magnet synchronous motor permanent magnet 8 adopts a surface-mount structure. The permanent magnet synchronous motor is a three-phase 10-pole structure.

[0042] like Figure 4 As shown, the hybrid excitation motor also includes a housing 9, an end cover 10 adapted to the housing 9, and a shaft 11 located inside the housing for housing the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor, wherein the rotor 2 of the excitation synchronous reluctance motor and the rotor 6 of the permanent magnet synchronous motor are mounted in parallel on the shaft 11.

[0043] like Figure 5As shown, the rectifier power circuit includes power switching transistors T1, T2, T3, T4, T5, and T6, diodes D1, D2, D3, D4, D5, and D6, and capacitor C1. The emitter of power switching transistor T1 is connected to the anode of diode D1, and the collector of power switching transistor T1 is connected to the cathode of diode D1. The emitter of power switching transistor T2 is connected to the anode of diode D2, and the collector of power switching transistor T2 is connected to the cathode of diode D2. The emitter of power switching transistor T3 is connected to the anode of diode D3, and the collector of power switching transistor T3 is connected to the cathode of diode D3. The emitter of power switching transistor T4 is connected to the anode of diode D4, and the collector of power switching transistor T4 is connected to the cathode of diode D4. The emitter of power switching transistor T5 is connected to the anode of diode D5, and the collector of power switching transistor T5 is connected to the cathode of diode D5. The emitter of power switch T6 is connected to the anode of diode D6, and the collector of power switch T6 is connected to the cathode of diode D6. The emitter of power switch T1 is connected to the collector of power switch T4, the emitter of power switch T3 is connected to the collector of power switch T6, and the emitter of power switch T5 is connected to the collector of power switch T2. The collectors of power switch T1, T3, and T5 form the positive output terminal of the rectifier power circuit. The emitters of power switch T4, T6, and T2 form the negative output terminal of the rectifier power circuit. The emitters of power switch T1, T3, and T5 respectively form the input terminals of the rectifier power circuit. The output terminal of the rectifier power circuit passes through capacitor C1, and the generator control unit outputs control signals PWMT1~T6 to control the chopping of power switches T1~T6 in the rectifier power circuit.

[0044] like Figure 6 As shown, the excitation power circuit includes power switch T7, power switch T8, diode D7, diode D8, and capacitor C2. The emitter of power switch T7 is connected to the cathode of diode D7, forming the positive output terminal of the excitation power circuit. The collector of power switch T7 is connected to the cathode of diode D8, forming the positive input terminal of the excitation power circuit. The emitter of power switch T8 is connected to the anode of diode D7, forming the negative output terminal of the excitation power circuit. The collector of power switch T8 is connected to the anode of diode T8, forming the negative input terminal of the excitation power circuit. The input terminal of the excitation power circuit passes through capacitor C2, and the power generation control unit outputs the control signal PWM. T7～T8 The power switching transistors T7 and T8 in the excitation power control circuit are used for chopping.

[0045] The present invention discloses a control method for a hybrid excitation controllable power generation system based on temperature detection, comprising the following steps:

[0046] Current sensor H a Current sensor H b Current sensor H c The measured three-phase armature winding current i of the hybrid excitation motor a i b i c Transmitted to the power generation control unit; voltage sensor H f The voltage signal u at the output of the rectifier power circuit obtained by detection o The rotor position signal of the hybrid excitation motor, detected by the position sensor, is used to calculate the speed of the hybrid excitation motor, which is then transmitted to the power generation control unit. Temperature sensors one and two respectively detect the stator winding temperature signal T of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b The signal is transmitted to the power generation control unit, which then uses the temperature signal T from the stator winding of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b Determine the control mode and output switching signal S of the hybrid excitation power distribution controllable generator system. K1 S K2 Control the closing or opening of switches K1 and K2 respectively.

[0047] The specific methods for determining the control mode of the hybrid excitation power distribution controllable power generation system and for the output switch signals SK1 and SK2 to control the closing or opening of switches K1 and K2 respectively are as follows:

[0048] The system receives the start signal from the data bus, completes the self-test procedure, and the power generation control unit detects the speed of the hybrid excitation motor, waiting for the speed n to reach the speed range required for system operation, i.e., n... min ≤n≤n max When switch K1 is closed, the generator controller performs power generation control and compares the stator winding temperature T of the electrically excited synchronous reluctance motor. a With set temperature T a * And the stator winding temperature T of the permanent magnet synchronous motor b With a given temperature T b * ;

[0049] When T a ≤T a *When the system enters control mode one, the control objective of control mode one is to minimize the copper loss of the power generation system under constant voltage operation, and to establish the minimum excitation current I required for constant voltage output of the hybrid excitation motor under different operating conditions. f With minimum weak magnetic current I d The lookup table is stored in the generator control unit; based on the load and the speed signal received by the generator control unit, the minimum excitation current I at this time is obtained. f * With the minimum d-axis weak magnetic current I d * The generator control unit adjusts the duty cycle of power switches T7 and T8 in the excitation power circuit to adjust the current of the excitation winding to I. f * The generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β PWM is generated through SVPWM control. T1～T6 The signal controls the switching on and off of the six power switching transistors T1 to T6 in the rectifier power circuit to maintain constant voltage output with minimum copper loss in the power generation system;

[0050] If T a >T a * Then determine T b With T b * The relationship, if T b ≤T b * Entering control mode two, the control objective of control mode two is to reduce the stator winding temperature of the permanent magnet synchronous motor to a given value T under constant pressure operation. b * The following describes the minimum excitation current I in control mode one. f Based on this, the excitation current is increased, and the generator control unit searches for the minimum field weakening current I based on the increased excitation current. dThe generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, the d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β Through SVPWM control, PWMT1 to T6 signals are generated to control the switching on and off of the six power switches T1 to T6 in the rectifier power circuit. This is done when the temperature of the stator winding of the permanent magnet synchronous motor drops to a given value T. b * The following measures aim to minimize copper losses under the premise of constant voltage output;

[0051] If T b >T b * This indicates that the load has exceeded the operating range of the power generation system. The power generation control unit issues an unloading command, disconnects switch K2, and disconnects switch K1.

[0052] This invention switches control modes by detecting the stator winding temperature of a permanent magnet synchronous motor and an electrically excited synchronous reluctance motor. It optimizes power allocation while ensuring the safe and stable operation of both motors, and simultaneously detects short-circuit faults in the stator windings, thus improving system reliability. This optimized power allocation control method can unleash the power output capacity of high-power-density permanent magnet synchronous motors, which helps to overcome the design difficulties of excitation mechanisms in traditional hybrid-excitation uncontrolled rectifier power generation systems in wide-speed power generation, thereby broadening the application speed range.

Claims

1. A hybrid excitation controllable power generation system based on temperature detection, characterized in that: Includes a hybrid excitation motor, a generator controller, switch K1, and switch K2. The hybrid excitation motor includes an electrically excited synchronous reluctance motor and a permanent magnet synchronous motor arranged coaxially, and the generator controller includes a rectifier power circuit, an excitation power circuit, a generator control unit, and a current sensor H. a Current sensor H b Current sensor H c Voltage sensor H f Temperature sensor 1, temperature sensor 2, and a position sensor for detecting the rotor position of the hybrid excitation motor; The output terminal of the armature winding of the electrically excited synchronous reluctance motor is connected to the input terminal of the permanent magnet synchronous motor. The output terminal of the permanent magnet synchronous motor is connected to the input terminal of the rectifier power circuit. The positive output terminal of the rectifier power circuit is connected to the first contact of switch K2, the second contact of switch K2 is connected to the positive input terminal of the load, and the negative output terminal of the rectifier power circuit is connected to the negative input terminal of the load. The positive input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the first contact of switch K1, the second contact of switch K1 is connected to the positive output terminal of the excitation power circuit, and the negative input terminal of the excitation winding of the electrically excited synchronous reluctance motor is connected to the negative output terminal of the excitation power circuit. Current sensor H a Current sensor H b Current sensor H c The measured three-phase armature winding current i of the hybrid excitation motor a i b i c Transmitted to the power generation control unit, voltage sensor H f The voltage signal u at the output of the rectifier power circuit obtained by detection o The rotor position signal of the hybrid excitation motor, detected by the position sensor, is transmitted to the power generation control unit; the stator winding temperature signal T of the electrically excited synchronous reluctance motor, detected by temperature sensor one and temperature sensor two respectively, is transmitted to the power generation control unit. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b The signal is transmitted to the power generation control unit; the power generation control unit then uses the stator winding temperature signal T of the electrically excited synchronous reluctance motor. a Temperature signal T of the stator winding of the permanent magnet synchronous motor b Determine the control mode of the hybrid excitation power distribution controllable generator system, and the output switching signal S. K1 S K2 Control the closing or opening of switches K1 and K2 respectively; The power generation control unit detects the speed of the hybrid excitation motor and waits for the speed n to reach the speed range required for system operation, i.e., n min ≤n≤n max When switch K1 is closed, the generator controller performs power generation control and compares the stator winding temperature T of the electrically excited synchronous reluctance motor. a With set temperature T a * And the stator winding temperature T of the permanent magnet synchronous motor b With a given temperature T b * ; When T a ≤T a * When the system enters control mode one, the control objective of control mode one is to minimize the copper loss of the power generation system under constant voltage operation. If T a >T a * Then determine T b With T b * The relationship, if T b ≤T b * Entering control mode two, the control objective of control mode two is to reduce the stator winding temperature of the permanent magnet synchronous motor to a given value T under constant pressure operation. b * the following; If T b >T b * This indicates that the load has exceeded the operating range of the power generation system. The power generation control unit issues an unloading command, disconnects switch K2, and disconnects switch K1.

2. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The electrically excited synchronous reluctance motor includes an electrically excited synchronous reluctance motor stator core, an electrically excited synchronous reluctance motor rotor core, an electrically excited synchronous reluctance motor excitation winding, and an electrically excited synchronous reluctance motor armature winding. The electrically excited synchronous reluctance motor stator core includes a plurality of evenly distributed stator poles, and the electrically excited synchronous reluctance motor rotor core includes a plurality of evenly distributed rotor poles. The electrically excited synchronous reluctance motor excitation winding and the electrically excited synchronous reluctance motor armature winding are both wound on the stator poles of the electrically excited synchronous reluctance motor stator core.

3. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The permanent magnet synchronous motor includes a stator core, a rotor core, an armature winding, and permanent magnets. The stator core has several evenly distributed stator poles, the permanent magnets are surface-mounted, and the motor is a three-phase 10-pole structure.

4. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The rectifier power circuit includes power switches T1, T2, T3, T4, T5, and T6, diodes D1, D2, D3, D4, D5, and D6, and capacitor C1. The emitter of power switch T1 is connected to the anode of diode D1, and the collector of power switch T1 is connected to the cathode of diode D1. The emitter of power switch T2 is connected to the anode of diode D2, and the collector of power switch T2 is connected to the cathode of diode D2. The emitter of power switch T3 is connected to the anode of diode D3, and the collector of power switch T3 is connected to the cathode of diode D3. The emitter of power switch T4 is connected to the anode of diode D4, and the collector of power switch T4 is connected to the cathode of diode D4. The emitter of power switch T5 is connected to the anode of diode D5, and the collector of power switch T5 is connected to the cathode of diode D5. The emitter of power switch T6 is connected to the anode of diode D6, the collector of power switch T6 is connected to the cathode of diode D6, the emitter of power switch T1 is connected to the collector of power switch T4, the emitter of power switch T3 is connected to the collector of power switch T6, and the emitter of power switch T5 is connected to the collector of power switch T2. The collectors of power switch T1, power switch T3, and power switch T5 form the positive output terminal of the rectifier power circuit. The emitters of power switch T4, power switch T6, and power switch T2 form the negative output terminal of the rectifier power circuit. The emitters of power switch T1, power switch T3, and power switch T5 respectively form the input terminals of the rectifier power circuit. The rectified power output terminal passes through capacitor C1, and the generator control unit outputs control signals PWMT1~T6 to control the chopping of power switches T1~T6 in the rectifier power circuit.

5. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The excitation power circuit includes power switches T7 and T8, diodes D7 and D8, and capacitor C2. The emitter of power switch T7 is connected to the cathode of diode D7, forming the positive output terminal of the excitation power circuit. The collector of power switch T7 is connected to the cathode of diode D8, forming the positive input terminal of the excitation power circuit. The emitter of power switch T8 is connected to the anode of diode D7, forming the negative output terminal of the excitation power circuit. The collector of power switch T8 is connected to the anode of diode T8, forming the negative input terminal of the excitation power circuit. The excitation power input terminal passes through capacitor C2, and the generator control unit outputs a control signal PWM. T7～T8 The power switching transistors T7 and T8 in the excitation power control circuit are used for chopping.

6. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The hybrid excitation motor also includes a housing, an end cover adapted to the housing, and a shaft located inside the housing for housing an electrically excited synchronous reluctance motor and a permanent magnet synchronous motor.

7. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The power generation control unit is connected to an external battery, and the power generation control unit communicates with an external data bus.

8. The temperature-detection-based hybrid excitation controllable power generation system according to claim 1, characterized in that: The position sensor is connected to the power generation control unit through a decoder and a speed calculation unit. The rotor position signal of the hybrid excitation motor detected by the position sensor is transmitted to the power generation control unit after the speed is calculated by the decoder and the speed calculation unit.

9. A control method for a temperature-detection-based hybrid excitation controllable power generation system according to any one of claims 1 to 8, characterized in that, Includes the following steps: The current signal of the armature winding of the hybrid excitation motor is obtained by detecting the current sensor, the output voltage signal of the rectified power armature is obtained by the voltage sensor, the rotor position signal of the hybrid excitation motor is obtained by detecting the position sensor, and the winding temperature signals of the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor are obtained by the temperature sensor, and then sent to the power generation control unit. The power generation control unit determines the control mode of the hybrid excitation power distribution controllable power generation system based on the stator winding temperature signals of the electrically excited synchronous reluctance motor and the permanent magnet synchronous motor, and controls the closing or opening of switches K1 and K2 respectively based on the output switch signals.

10. The control method for a temperature-detection-based hybrid excitation controllable power generation system according to claim 9, characterized in that, The specific method for determining the control mode of the controllable power generation system with hybrid excitation power distribution and controlling the closing or opening of switches K1 and K2 with output switch signals is as follows: The system receives the start signal from the data bus and completes the self-test procedure; Enter control mode one, and establish the minimum excitation current I required for constant voltage output of the hybrid excitation motor under different operating conditions. f With minimum weak magnetic current I d The lookup table is stored in the generator control unit; based on the load and the speed signal received by the generator control unit, the minimum excitation current I at this time is obtained. f * With the minimum d-axis weak magnetic current I d * The generator control unit adjusts the duty cycle of power switches T7 and T8 in the excitation power circuit to adjust the current of the excitation winding to I. f * The generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β PWM is generated through SVPWM control. T1~T6 The signal controls the switching on and off of the six power switching transistors T1 to T6 in the rectifier power circuit to maintain constant voltage output with minimum copper loss in the power generation system; Entering control mode two, at the minimum excitation current I of control mode one. f Based on this, the excitation current is increased, and the generator control unit searches for the minimum field weakening current I based on the increased excitation current. d The generator control unit detects and compares the rectified power output voltage signal with the output voltage setpoint signal. After passing through the output voltage regulation stage, it generates the q-axis current setpoint signal. The detected three-phase armature winding current of the hybrid excitation motor is transformed to obtain the actual values ​​of the q-axis and d-axis currents. These are compared with the setpoint values ​​of the q-axis and d-axis currents, respectively. After passing through a PI circuit, d-axis and q-axis voltage vectors are generated. After coordinate transformation, the voltage vector v in the stationary coordinates is obtained. α v β Through SVPWM control, PWMT1~T6 signals are generated to control the switching on and off of the six power switches T1~T6 in the rectifier power circuit. This is done when the temperature of the stator winding of the permanent magnet synchronous motor drops to a given value T. b * The following measures aim to minimize copper losses under the premise of constant voltage output.

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