An efficiency optimal control method for an electrically excited double-salient controlled rectifier power generation system

Abstract

A method for optimal control of the efficiency of an electrically excited double-pole controlled rectifier power generation system, which changes the conduction angle of the angle position control of the controlled rectifier of the electrically excited double-pole generator under the premise of maintaining the bus voltage; records the torque, load-side current and voltage, and current of each winding of the electrically excited double-pole power generation system under different operating conditions and different conduction angles, and calculates the input power, excitation loss and output power of the controlled rectifier power generation system, and further calculates the overall efficiency of the system; establishes an efficiency optimization model of an electrically excited double-pole controlled rectifier power generation system in combination with the data of system efficiency under different operating conditions; obtains the conduction angle of the controlled rectifier when the efficiency is optimal under different operating conditions in combination with the controlled rectifier efficiency optimization PSO-BP model; and realizes optimal control of the system efficiency under different operating conditions in combination with the conduction angle. The present invention realizes the control of the sum of various losses to a minimum state under a wide range of operating conditions, thereby achieving the control target of optimal efficiency of the rectifier power generation system.

Description

Technical Field

[0001] The present invention relates to the field of electrical control, and in particular to an efficiency optimization control method for an electrically excited double-salient-pole controlled rectifier power generation system. Background Art

[0002] The electrically excited double-salient-pole generator is a motor with a salient-pole tooth-slot structure on both the stator and the rotor. Its structural feature is that in addition to the armature winding, the stator is also provided with an independent excitation winding to provide the excitation magnetic field, and no permanent magnets or windings are installed on the rotor. By adjusting the excitation current, the internal magnetic field of the generator can be adjusted, and the output performance of the generator can be adjusted through an external rectifier controller. The electrically excited double-salient-pole generator has a simple and reliable structure. When the controlled rectifier and the rotary transformer fail, it can be converted into an uncontrolled rectifier control mode to continue working. Therefore, it is particularly suitable for applications such as more-electric aircraft that require high reliability of motor operation.

[0003] The electrically excited doubly salient generator is the energy source and core component of the aviation power supply system. The operating efficiency of the electrically excited doubly salient generator affects the energy utilization rate of the entire aircraft electrical system. Reducing the overall loss of the electrically excited doubly salient rectifier power generation system and improving the operating efficiency of the power generation system are important methods to improve the energy utilization efficiency of more-electric aircraft and reduce fuel consumption and pollution emissions.

[0004] Controllable rectification of an electrically excited double-salient-pole generator is an important technical means to improve the output voltage and output power of an electrically excited double-salient-pole power generation system. Among the existing control methods, the angle position control method is more commonly used, in which a conduction angle β is set. The motor uses the same set conduction angle β in the entire operating range. The use of a controllable rectification angle position control method can improve the output voltage and output power of an electrically excited double-salient-pole generator.

[0005] However, there is currently a lack of scientific basis for the selection of the controllable rectifier conduction angle. The same conduction angle cannot always keep the electrically excited double-pole power generation system operating at the optimal efficiency under different working conditions. The use of different conduction angles will affect the output characteristics of the electrically excited double-pole generator, resulting in changes in parameters such as torque, load-side current and voltage, and each winding current, which will further affect the input power, overall loss and output power of the power generation system. The use of different conduction angles will lead to changes in the efficiency of the electrically excited double-pole power generation system. However, the issue of how to scientifically select the conduction angle that optimizes the output efficiency of the power generation system remains to be studied.

[0006] After searching, the Chinese patent application number CN111313779A discloses a controllable rectifier minimum copper loss control method based on an electrically excited double-pole generator, providing users with a control solution that effectively suppresses copper loss and reduces heat generation. The technical scheme is as follows: the control process includes the acquisition and calculation of motor parameters, obtaining the corresponding relationship between the shutdown angle and copper loss under different working conditions, establishing a controllable rectifier copper loss model and performing copper loss minimum control, wherein: the acquisition and calculation of motor parameters is to maintain the bus voltage at the rated voltage, keep the working condition unchanged, measure the relevant parameters under the working condition, and calculate the copper loss under the working condition; on the basis of the above operations, change the working condition, measure the parameters under different working conditions and calculate the corresponding copper loss, and obtain the corresponding relationship between the shutdown angle and copper loss under different working conditions; on the basis of the above corresponding relationship between the shutdown angle and copper loss, use an extreme learning machine to establish a controllable rectifier copper loss model; use the above copper loss model to obtain the shutdown angle when the copper loss is the minimum under all working conditions, and use the shutdown angle to select the corresponding shutdown angle according to the actual operating conditions for control to achieve the purpose of minimum copper loss control. This project takes the overall loss and system efficiency of the electrically excited double-pole controlled rectifier power generation system as the optimization target, collects torque, speed, winding current and other parameters, and constructs the optimal efficiency model of the electrically excited double-pole controlled rectifier power generation system based on the BP neural network algorithm after particle swarm optimization to achieve optimal control of the power generation system efficiency. Compared with this invention, the minimum copper loss optimization method is different in that: 1. The present invention calculates the mechanical power and excitation power by collecting parameters such as torque, speed, winding current, etc., to calculate the input power of the generator; 2. The present invention introduces the particle swarm optimization BP neural network (PSO-BP) algorithm to construct the optimal efficiency model of the electrically excited double-pole controlled rectifier power generation system, and the result of system efficiency optimization is more accurate; 3. The present invention takes the overall loss and overall efficiency of the power generation system as the optimization target, and no longer optimizes a single parameter of the power generation system. The control process covers the comprehensive optimization of multiple losses such as copper loss and iron loss.

[0007] In the prior art, the control method for optimizing the efficiency of the controlled rectifier power generation system of the electrically excited double-pole generator has the disadvantages of lack of scientific basis for the selection of the conduction angle, failure to minimize the overall loss of the power generation system, and failure to optimize the system to the maximum extent. There is a lack of a method that can make the electrically excited double-pole power generation system operate in the most efficient mode in the full range of operating conditions. Summary of the invention

[0008] In order to solve the above technical problems, the present invention proposes an efficiency optimal control method for an electrically excited double-pole controlled rectifier power generation system, which can quickly model the efficiency of the electrically excited double-pole controlled rectifier power generation system, obtain the efficiency optimal control parameters, and achieve the optimal efficiency of the power generation system under the entire operating range.

[0009] To achieve the above object, the technical solution of the present invention is as follows:

[0010] An efficiency optimal control method for an electrically excited double-salient controlled rectifier power generation system, comprising:

[0011] S1. Keep the bus voltage at the rated voltage, keep the working condition unchanged, change the conduction angle in the controlled rectifier angle position control of the electrically excited doubly salient generator, and measure the torque, load side current and voltage, and current of each winding corresponding to different conduction angles under the working condition;

[0012] In step S1, keeping the operating condition unchanged means keeping the speed and load of the electrically excited double-salient-pole generator unchanged;

[0013] Changing the angle position of the controlled rectifier to control the conduction angle refers to changing the angle position of the controlled rectifier in the electrically excited double-salient controlled rectifier power generation system to control the conduction angle, thereby changing the various losses of the power generation system and thus changing the power generation power;

[0014] S2. Using the above parameters, combined with the internal resistance of the excitation winding, the load resistance and the speed, the input power, excitation loss and output power of the electrically excited double-pole generator are calculated, and the overall efficiency of the electrically excited double-pole power generation system is calculated to obtain the relationship between the controllable rectifier conduction angle and the system efficiency under this working condition;

[0015] The calculation method of excitation loss, torque input power and system input power is:

[0016] P if =i f_RMS *i f_RMS *r f

[0017] P t =1000*n*t / 9550

[0018] P in =P if +P t

[0019] Where P if is the excitation loss of the electrically excited doubly salient-pole generator, i f_RMS is the excitation current i detected in S1 f The effective value, r f is the internal resistance of the field winding. t is the torque input power of the electrically excited double-salient-pole generator, n is the speed of the electrically excited double-salient-pole generator, t is the instantaneous torque of the electrically excited double-salient-pole generator detected in S1, P in Input power to the electrically excited double-salient-pole generating system;

[0020] The calculation method of system output power and system efficiency is:

[0021] P L =i DC *u DC

[0022] η=P L / P in

[0023] Where P L is the output power of the electrically excited double-salient-pole generator system, i DC is the output current detected in S1, u DC is the output voltage detected in S1. η is the efficiency of the electrically excited double-salient-pole power generation system;

[0024] S3, changing the working condition, repeating S1 and S2, and obtaining the relationship between the conduction angle and the system efficiency of the electrically excited double-salient-pole controlled rectifier power generation system under different working conditions;

[0025] In step S3, the corresponding relationship between the conduction angle and the efficiency of the power generation system under different working conditions is obtained, which means that under the corresponding working condition range, the speed or load is changed at equal intervals, and under the same working condition, the angle position of the controlled rectifier in the electrically excited double-salient controlled rectifier power generation system is changed at equal intervals to control the conduction angle, and the parameters of different conduction angles are collected and the system efficiency is calculated to obtain the relationship between the conduction angle and the efficiency of the power generation system;

[0026] S4. Using the relationship between the conduction angle and system efficiency of the electrically excited double-pole controlled rectifier power generation system under the different working conditions, a PSO-BP algorithm is used to establish an efficiency model of the electrically excited double-pole controlled rectifier power generation system;

[0027] S5. Using the efficiency model of the electrically excited double-salient-pole controlled rectifier power generation system, obtain the conduction angle when the efficiency is optimal under all operating conditions;

[0028] S6. By using the conduction angle corresponding to the optimal efficiency under all operating conditions, the conduction angle of the controlled rectifier corresponding to the optimal efficiency under the operating condition can be selected for control according to the actual operating condition of the electrically excited double-salient-pole generator, thereby achieving optimal efficiency control;

[0029] In step S6, the efficiency optimal control refers to using the above-mentioned power generation system efficiency model to obtain the conduction angle that optimizes the system efficiency according to the actual operation of the electrically excited double-pole controlled rectifier power generation system, and adaptively performing the system efficiency optimal control according to the operating conditions.

[0030] As a further improvement of the present invention, in step S1, the conduction angle in the controllable rectifier angle position control of the electrically excited doubly salient pole generator is changed, so that the conduction angle is within the range of 0° to 60°, and a sampling point is taken every 10°.

[0031] As a further improvement of the present invention, in step S3, the changing of the working condition includes taking 10 or more sampling points at equal intervals within the rated power range of the load under the condition that the speed remains unchanged;

[0032] In step S3, the changing working condition includes taking 5 or more sampling points within the rated speed range when the load remains unchanged.

[0033] As a further improvement of the present invention, in step S3, the operating condition range is a speed of 4000 to 8000 r / min and a load of 1 to 10 kW.

[0034] As a further improvement of the present invention, in step S4, the learning and training method of the PSO-BP algorithm includes:

[0035] S41, using the PSO algorithm to optimize the weights and thresholds of the BP neural network algorithm to form a PSO-BP algorithm;

[0036] S42, inputting various parameters of the electrically excited double-salient-pole controlled rectifier power generation system into the PSO-BP algorithm for training, and verifying the obtained training results;

[0037] S43. After the PSO-BP algorithm is trained, the rotational speed, load and controllable rectifier conduction angle are input to obtain the system efficiency obtained by regression of the PSO-BP algorithm, that is, to obtain the efficiency model of the electrically excited double-salient-pole controlled rectifier power generation system.

[0038] As a further improvement of the present invention, in step S4, the rotation speed, load and controllable rectifier conduction angle are independent variables of the PSO-BP algorithm, and the system efficiency is the dependent variable of the PSO-BP algorithm.

[0039] As a further improvement of the present invention, the electrically excited double-pole controlled rectifier power generation system includes an electrically excited double-pole generator A1 and a generator controller A2, wherein the generator controller A2 includes an excitation controller A3, a DC output voltage u DC The output voltage sensor A4 is used to detect the DC output current i DC The output current sensor A5 and the load A6 are used to detect the excitation current i f The excitation current sensor A7, the resolver A8 for detecting the rotor position angle θ, the controllable rectifier A9, the system efficiency optimal control method A10, the torque and speed sensor A11 for detecting the motor torque t and the speed n, the generator controller A2 adopts the control method of the output voltage outer loop and the excitation current inner loop, the output voltage outer loop is controlled by the PI controller according to the feedback DC output voltage u DC And the reference value of the output voltage u ref Calculate the reference value of the excitation current ifref The excitation current inner loop calculates the duty cycle d of the excitation controller A3 through the PID controller, so that the bus voltage is stabilized at the rated voltage. The speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator are obtained through the torque and speed sensor A11, the bus current sensor and the voltage sensor, and the winding current sensor. According to the speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator, the input power, excitation loss and output power are calculated. The system power corresponding to the conduction angle under different working conditions is further calculated, and the conduction angle data corresponding to the optimal efficiency of the electrically excited double-pole power generation system under different working conditions are selected to perform system optimal control of the electrically excited double-pole power generation system.

[0040] The present invention includes changing the conduction angle of the angle position control of the controlled rectifier of the electrically excited double-pole generator under the premise of maintaining the bus voltage; recording the torque of the electrically excited double-pole generator under different working conditions and different conduction angles, the load side current and voltage, and the current of each winding, and calculating the efficiency of the power generation system; using the PSO-BP algorithm to establish an efficiency model of the electrically excited double-pole controlled rectifier power generation system in combination with the obtained system efficiency data; combining the PSO-BP algorithm model of the controllable rectifier system efficiency to obtain the controlled rectifier conduction angle when the efficiency is optimal under different working conditions; combining the conduction angle to achieve optimal efficiency control under different working conditions. The present invention is suitable for applications such as aviation power generation systems that have strict requirements on efficiency.

[0041] The beneficial effects of the present invention are as follows:

[0042] (1) The present invention utilizes the original controller and sensor of the electrically excited double-pole controlled rectifier power generation system, and has the advantages of simple and reliable structure, high technical maturity, and low failure rate.

[0043] (2) The present invention collects parameters such as the torque, load-side voltage and current, and winding current of the electrically excited double-pole generator at different conduction angles under different operating conditions, calculates the total system loss and further obtains the system efficiency. The calculation result is relatively accurate and has a relatively scientific reference significance for the efficiency calculation of the electrically excited double-pole controlled rectifier system.

[0044] (3) The present invention utilizes a machine learning algorithm to achieve rapid modeling of the efficiency of the power generation system, and obtain the system efficiency distribution over a wide range of operating conditions with less experimental testing work, which greatly saves experimental workload, calculation amount and calculation time, and provides a reference for the optimization of other system parameters.

[0045] (3) The present invention takes system efficiency as the optimization goal, involves optimization analysis of multiple losses, and uses the PSO-BP algorithm to obtain the relationship between the conduction angle and system efficiency in the angular position control method to achieve rapid adjustment control, effectively suppressing the overall loss of the system, so that the system always operates in the most efficient working state under the full range of operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 It is a control block diagram of an efficiency optimal control method for an electrically excited double-salient controlled rectifier power generation system;

[0048] Figure 1 The parameter i in f is the excitation current, in this case the rated range is 0~6A; u DC is the bus voltage, which in this example ranges from 250 to 330 V; i DC is the bus current, which in this case ranges from 0 to 33A; d is the excitation drive duty cycle, which ranges from 0 to 1; β is the conduction angle in the controllable rectifier angle position control, which ranges from 0 to 120°;

[0049] Figure 2 is a stereogram of an electrically excited doubly salient pole generator;

[0050] Figure 3 is a cross-sectional view of an electrically excited doubly salient generator;

[0051] Figure 2 and Figure 3 The diagram is as follows:

[0052] 1. Rotor B1; 2. Stator core B2; 3. Field winding B3; 4. Armature winding B4;

[0053] Figure 4 is the system efficiency corresponding to different loads and conduction angles of the electrically excited doubly salient generator at 8000 rpm;

[0054] Figure 5 It is the principle framework diagram of the particle swarm optimization BP neural network (PSO-BP) algorithm modeling of the efficiency of the electrically excited double-salient-pole power generation system;

[0055] Figure 6 is the conduction angle corresponding to the optimal efficiency in the optimal control method for the efficiency of the electrically excited doubly salient pole generator system;

[0056] Figure 7 It is the system efficiency optimization value of the electrically excited double-pole generator system after adopting the efficiency optimal control method compared with the uncontrolled rectifier system. DETAILED DESCRIPTION

[0057] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0058] Embodiment 1:

[0059] The embodiment of the present invention provides an efficiency optimization control method for an electrically excited double-salient-pole controlled rectifier power generation system. The structure of the electrically excited double-salient-pole generator is as follows: Figure 2 and Figure 3 As shown, it includes a rotor B1 and a stator core B2. The stator is equipped with an excitation winding B3 and an armature winding B4. The excitation magnetic field of the generator is provided by the excitation winding B3. By changing the excitation current in the excitation winding B3, the excitation magnetic field inside the generator can be adjusted.

[0060] The control system of this embodiment is operated as follows Figure 1 As shown, the system mainly consists of an electrically excited double-pole generator A1, a generator controller A2 (including an excitation controller A3), and a controller for detecting the DC output voltage u DC The output voltage sensor A4 is used to detect the DC output current i DC The output current sensor A5 and the load A6 are used to detect the excitation current i f The generator controller A2 adopts the control method of output voltage outer loop and excitation current inner loop. The output voltage outer loop is controlled by PI controller according to the feedback DC output voltage u DC And the reference value of the output voltage u ref Calculate the reference value of the excitation current i fref . The excitation current inner loop calculates the duty cycle d of the excitation controller A3 through the PID controller, so that the bus voltage is stabilized at the rated voltage. The speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator can be obtained through the torque and speed sensor A11, the bus current sensor and the voltage sensor, as well as the winding current sensor. According to the speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator, the input power, excitation loss and output power are calculated, and the system power corresponding to the conduction angle under different working conditions is further calculated. The conduction angle data corresponding to the optimal efficiency of the electrically excited double-pole power generation system under different working conditions are selected to perform system optimal control of the electrically excited double-pole power generation system.

[0061] The efficiency optimization control method of the electrically excited double-salient-pole controlled rectifier power generation system of the present invention comprises:

[0062] The armature winding of the electrically excited double-salient-pole generator is connected to a three-phase full-bridge controlled rectifier, and the excitation winding is connected to an excitation controller. The bus voltage is controlled by the generator controller to keep the bus voltage at the rated voltage.

[0063] S1. Keep the electrically excited doubly salient pole generator working under a certain working condition, that is, keep the speed unchanged, keep the load unchanged, change the conduction angle in the controlled rectifier angle position control of the electrically excited doubly salient pole generator at intervals, and measure the torque, excitation current, output current and output voltage corresponding to different conduction angles. For the selection of the conduction angle, as many points as possible should be selected at even intervals within the entire operating range. The conduction angle selection range in this example is 0° to 60°, and the change interval is 10°. Record the conduction angle, torque, excitation current, output current, output voltage and other data of the electrically excited doubly salient pole generator at this speed and load;

[0064] S2. Calculate the efficiency of the electrically excited double-pole power generation system using the torque, excitation current, output current and output voltage in combination with the internal resistance of the excitation winding and the speed, record the corresponding data of the conduction angle and system efficiency of the electrically excited double-pole generator at the speed and load, and obtain the corresponding relationship between the controllable rectifier conduction angle and the system efficiency under this working condition.

[0065] The calculation method of excitation loss, torque input power and system input power is:

[0066] P if =i f_RMS *i f_RMS *r f

[0067] P t =1000*n*t / 9550

[0068] P in =P if +P t

[0069] Where P if is the excitation loss of the electrically excited doubly salient-pole generator, i f_RMS is the excitation current i detected in S1 f The effective value, r f is the internal resistance of the field winding. t is the torque input power of the electrically excited double-salient-pole generator, n is the speed of the electrically excited double-salient-pole generator, t is the instantaneous torque of the electrically excited double-salient-pole generator detected in S1, P in Input power to the electrically excited doubly salient generating system.

[0070] The calculation method of system output power and system efficiency is:

[0071] P L =i DC *u DC

[0072] η=P L / P in

[0073] Where P L is the output power of the electrically excited double-salient-pole generator system, i DC is the output current detected in S1, u DC is the output voltage detected in S1. η is the efficiency of the electrically excited double-salient-pole power generation system;

[0074] S3. Change the speed or load of the electrically excited double-pole generator, repeat S1 and S2, and obtain the corresponding data of the conduction angle and system efficiency of the electrically excited double-pole controlled rectifier power generation system under different working conditions, i.e., the same speed and different loads and different speeds and the same loads. For the selection of speed and load, as many points as possible should be selected evenly spaced within the entire operating range. In this example, the load change range is 0kW~10kW, with a change interval of 1kW; the speed range is 4000~8000r / min, with a change interval of 1000r / min. Record the speed, load, conduction angle and system efficiency data of the electrically excited double-pole generator;

[0075] S4. Using the corresponding data of the conduction angle and system efficiency of the electrically excited double-pole controlled rectifier power generation system under the different operating conditions, the PSO-BP algorithm is used to establish an efficiency model of the electrically excited double-pole controlled rectifier power generation system. The speed, load, conduction angle and system efficiency data of the electrically excited double-pole power generation system under different operating conditions are normalized, and the PSO-BP algorithm is trained with the speed, load and conduction angle as independent variables and the system efficiency as the dependent variable. By training and testing the PSO-BP algorithm, the efficiency model of the electrically excited double-pole controlled rectifier power generation system is obtained. Using this model, the independent variables of the efficiency model of the electrically excited double-pole controlled rectifier power generation system are speed, load and conduction angle, and the dependent variable is the efficiency of the electrically excited double-pole power generation system;

[0076] S5. Using the efficiency model of the electrically excited double-salient pole controlled rectifier power generation system, input different conduction angles under any working condition to obtain the system efficiency data under the corresponding conditions. By comparing the system efficiency data corresponding to different conduction angles, the conduction angle corresponding to the optimal system efficiency under the working condition can be found. Then, the conduction angle data that optimizes the efficiency of the electrically excited double-salient pole power generation system under all working conditions is obtained; the full working condition refers to various working times under the operating boundary conditions, that is, various working conditions within the rated power range + rated speed range.

[0077] S6. Utilize the conduction angle when the system efficiency is optimal under the full operating conditions, select the conduction angle corresponding to the controllable rectifier according to the actual operating conditions of the electrically excited double-pole power generation system, and realize optimal control of the system efficiency.

[0078] Furthermore, the different operating conditions include the main external variables that affect the working state of the electrically excited doubly salient generator, namely, the speed and the load. Under different speeds and / or loads, the working state of the electrically excited doubly salient generator is different, so it is necessary to determine the corresponding control parameters according to different operating conditions.

[0079] Furthermore, the learning and training method of the PSO-BP algorithm in the present invention includes:

[0080] S41, using the rotation speed, load and controllable rectifier conduction angle as input parameters of the PSO-BP algorithm, and using the system efficiency as an output parameter of the PSO-BP algorithm for training;

[0081] S12. After the PSO-BP algorithm is trained, the speed, load and controllable rectifier conduction angle are input to obtain the system efficiency obtained by regression of the PSO-BP algorithm, that is, the efficiency model of the electrically excited double-pole controlled rectifier power generation system is obtained.

[0082] Furthermore, by changing the conduction angle of the controlled rectifier of the electrically excited double-salient-pole generator, optimal control of the efficiency of the electrically excited double-salient-pole power generation system is achieved.

[0083] Furthermore, in S5, the system efficiency model obtained by the PSO-BP algorithm is used to obtain the controllable rectifier conduction angle corresponding to the optimal efficiency under different working conditions.

[0084] Furthermore, in S4, the rotation speed, load and controllable rectifier conduction angle are independent variables of the PSO-BP algorithm, and the system efficiency is the dependent variable of the PSO-BP algorithm.

[0085] Test example:

[0086] Further test results based on Example 1 are as follows:

[0087] Figure 4 It is part of the system efficiency data obtained by measuring the torque, current, and voltage of the electrically excited double-pole generator in S1 and S2 and calculating the system efficiency. The figure shows the system efficiency of an electrically excited double-pole generator with a rated power of 9kW and a rated voltage of 270V at 8000 rpm. In the figure, the conduction angle is between 0 and 60°, and the sampling is at 10° intervals; the power is between 1 and 10kW, and the sampling is at 1kW intervals. The system efficiency distribution obtained is between 80% and 95%.

[0088] Figure 5 This is a principle architecture diagram of the PSO-BP algorithm modeling of the efficiency of the electrically excited double-pole power generation system. The speed, load and controllable rectifier conduction angle are used as input parameters of the PSO-BP algorithm, and the system efficiency is used as the output parameter of the PSO-BP algorithm for training. After the PSO-BP algorithm is trained, the speed, load power and controllable rectifier conduction angle are input to obtain the system efficiency obtained by the PSO-BP algorithm regression, that is, the efficiency model of the electrically excited double-pole controlled rectifier power generation system is obtained.

[0089] Figure 6 It is the conduction angle corresponding to the optimal efficiency in the efficiency optimal control method of the electrically excited double-pole power generation system. Using the efficiency model of the electrically excited double-pole controlled rectifier power generation system, the conduction angle corresponding to the working point where the system efficiency is the maximum value under any operating condition under all operating conditions can be found. By finding the conduction angle corresponding to the maximum system efficiency under any operating condition under all operating conditions, the corresponding control angle can be obtained for the optimal control of the controllable rectifier system efficiency. For the 270V 9kW electrically excited double-pole generator in this example, within the load range of 0 to 10kW and the speed range of 4000 to 8000r / min, the conduction angle at which the system efficiency takes the maximum value is between 0° and 40°.

[0090] Figure 7 It is the system efficiency value improved by the electrically excited double-pole generator after adopting the system efficiency optimal control method compared with the uncontrolled rectifier system. It can be seen that the electrically excited double-pole controlled rectifier power generation system efficiency optimal control method can achieve a significant optimization of the system efficiency and achieve optimal control of the system efficiency. By adopting this method, the system efficiency can be improved by more than 5% (under 1kW load, 7000r / min working conditions).

[0091] In summary, the beneficial effects of the present invention are:

[0092] (1) The system efficiency optimization model of the present invention utilizes the existing controllable rectifier system and voltage, current, torque and other detection devices to detect parameters such as speed, load, winding current, torque, etc., without the need to purchase additional detection and control devices, effectively reducing experimental costs and time and improving the reliability of system operation;

[0093] (2) The modeling method described in the present invention can obtain the corresponding relationship between the control conduction angle and the system efficiency under all working conditions through less experimental data collection. It effectively reduces the workload, calculation amount and time cost of measurement and calculation. The established system efficiency model has high prediction accuracy and good generalization, and is suitable for optimizing the efficiency of the electrically excited double-pole power generation system;

[0094] (3) The control method proposed in the present invention provides a scientific reference for the conduction angle selection of the electrically excited double-pole controlled rectifier power generation system, changing the previous situation where there was no basis for the conduction angle selection of the controlled rectifier. By using the conduction angle under all working conditions, the maximum control of the system efficiency is achieved. The control method of the present invention reduces the overall loss of the electrically excited double-pole power generation system and improves the working efficiency of the power generation system.

[0095] (4) The modeling method described in the present invention is well adapted to the parameter optimization of the generator system and can be widely used in the online measurement and optimization of the parameters of the power generation system. At the same time, it can realize measurement, learning and modeling throughout the entire life cycle, fully adapt to the changes in the parameters of the generator system, and realize the optimization control of diversified parameters.

[0096] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. An efficiency optimization control method for an electrically excited double-salient controlled rectifier power generation system, characterized in that: include: S1. Keep the bus voltage at the rated voltage, keep the working condition unchanged, change the conduction angle in the controlled rectifier angle position control of the electrically excited doubly salient generator, and measure the torque, load side current and voltage, and current parameters of each winding corresponding to different conduction angles under the working condition; In step S1, keeping the operating condition unchanged means keeping the speed and load of the electrically excited double-salient-pole generator unchanged; Changing the angle position of the controlled rectifier to control the conduction angle refers to changing the angle position of the controlled rectifier in the electrically excited double-salient controlled rectifier power generation system to control the conduction angle, thereby changing the various losses of the power generation system and thus changing the power generation power; S2. Using the above parameters, combined with the internal resistance of the excitation winding, the load resistance and the speed data, the input power, excitation loss and output power of the electrically excited double-pole generator are calculated, and the overall efficiency of the electrically excited double-pole power generation system is calculated to obtain the relationship between the controllable rectifier conduction angle and the system efficiency under this working condition; The calculation method of excitation loss, torque input power and system input power is: P if =i f_RMS *i f_RMS *r f P t =1000*n*t / 9550 P in =P if +P t Where P if is the excitation loss of the electrically excited doubly salient-pole generator, i f_RMS is the excitation current i detected in S1 f The effective value, r f is the internal resistance of the excitation winding, P t is the torque input power of the electrically excited double-salient-pole generator, n is the speed of the electrically excited double-salient-pole generator, t is the instantaneous torque of the electrically excited double-salient-pole generator detected in S1, P in Input power to the electrically excited double-salient-pole generating system; The calculation method of system output power and system efficiency is: P L =and DC *in DC η6P L / P in Where P L is the output power of the electrically excited double-salient-pole generator system, i DC is the output current detected in S1, u DC is the output voltage detected in S1, and η is the efficiency of the electrically excited double-salient-pole power generation system; S3, changing the working condition, repeating S1 and S2, and obtaining the relationship between the conduction angle and the system efficiency of the electrically excited double-salient-pole controlled rectifier power generation system under different working conditions; In step S3, the corresponding relationship between the conduction angle and the efficiency of the power generation system under different working conditions is obtained, which means that under the corresponding working condition range, the speed or load is changed at equal intervals, and under the same working condition, the angle position of the controlled rectifier in the electrically excited double-salient controlled rectifier power generation system is changed at equal intervals to control the conduction angle, and the parameters of different conduction angles are collected and the system efficiency is calculated to obtain the relationship between the conduction angle and the efficiency of the power generation system; S4. Using the relationship between the conduction angle and system efficiency of the electrically excited double-pole controlled rectifier power generation system under the different working conditions, a PSO-BP algorithm is used to establish an efficiency model of the electrically excited double-pole controlled rectifier power generation system; S5. Using the efficiency model of the electrically excited double-salient-pole controlled rectifier power generation system, obtain the conduction angle when the efficiency is optimal under all operating conditions; S6. By using the conduction angle corresponding to the optimal efficiency under all operating conditions, the conduction angle of the controlled rectifier corresponding to the optimal efficiency under the operating condition can be selected for control according to the actual operating condition of the electrically excited double-salient-pole generator, thereby achieving optimal efficiency control; In step S6, the efficiency optimal control refers to using the above-mentioned power generation system efficiency model to obtain the conduction angle that optimizes the system efficiency according to the actual operation of the electrically excited double-pole controlled rectifier power generation system, and adaptively performing the system efficiency optimal control according to the operating conditions.

2. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to claim 1, characterized in that: In the step S1, the conduction angle in the controlled rectifier angle position control of the electrically excited doubly salient generator is changed, and the conduction angle is within the range of 0° to 60°, and a sampling point is taken every 10°.

3. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to claim 1, characterized in that: In step S3, the changing working condition includes taking 10 or more sampling points at equal intervals within the rated power range of the load under the condition that the speed remains unchanged; In step S3, the changing working condition includes taking 5 or more sampling points within the rated speed range when the load remains unchanged.

4. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to claim 1, characterized in that: In step S3, the operating range is a speed of 4000 to 8000 r / min and a load of 1 to 10 kW.

5. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to claim 1, characterized in that: In step S4, the learning and training method of the PSO-BP algorithm includes: S41, using the PSO algorithm to optimize the weights and thresholds of the BP neural network algorithm to form a PSO-BP algorithm; S42, inputting various parameters of the electrically excited double-salient-pole controlled rectifier power generation system into the PSO-BP algorithm for training, and verifying the obtained training results; S43. After the PSO-BP algorithm is trained, the rotational speed, load and controllable rectifier conduction angle are input to obtain the system efficiency obtained by regression of the PSO-BP algorithm, that is, to obtain the efficiency model of the electrically excited double-salient-pole controlled rectifier power generation system.

6. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to claim 5, characterized in that: In step S4, the rotation speed, load and controllable rectifier conduction angle are independent variables of the PSO-BP algorithm, and the system efficiency is the dependent variable of the PSO-BP algorithm.

7. The method for optimizing efficiency of an electrically excited doubly salient controlled rectifier power generation system according to any one of claims 1 to 6, characterized in that: The electrically excited double-salient pole controlled rectifier power generation system comprises an electrically excited double-salient pole generator A1 and a generator controller A2, wherein the generator controller A2 comprises an excitation controller A3 and a controllable rectifier for detecting a DC output voltage u DC The output voltage sensor A4 is used to detect the DC output current i DC The output current sensor A5 and the load A6 are used to detect the excitation current i f The excitation current sensor A7, the resolver A8 for detecting the rotor position angle θ, the controllable rectifier A9, the system efficiency optimal control method A10, the torque and speed sensor A11 for detecting the motor torque t and the speed n, the generator controller A2 adopts the control method of the output voltage outer loop and the excitation current inner loop, the output voltage outer loop is controlled by the PI controller according to the feedback DC output voltage u DC And the reference value of the output voltage u ref Calculate the reference value of the excitation current i fref The excitation current inner loop calculates the duty cycle d of the excitation controller A3 through the PID controller, so that the bus voltage is stabilized at the rated voltage. The speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator are obtained through the torque and speed sensor A11, the bus current sensor and the voltage sensor, and the winding current sensor. According to the speed, torque, excitation current, output current and output voltage of the electrically excited double-pole generator, the input power, excitation loss and output power are calculated. The system power corresponding to the conduction angle under different working conditions is further calculated, and the conduction angle data corresponding to the optimal efficiency of the electrically excited double-pole power generation system under different working conditions are selected to perform system optimal control of the electrically excited double-pole power generation system.

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