阅读说明：本技术 自励变励磁电压变发电电压的多变量开关磁阻发电机变流系统 (Multivariable switch reluctance generator current transformation system capable of self-exciting to change excitation voltage to generate voltage ) 是由 孙冠群 张琳涵 邬舒宁 于 2019-10-17 设计创作，主要内容包括：自励变励磁电压变发电电压的多变量开关磁阻发电机变流系统,由七个开关管、三相绕组、五个二极管、四个电容器、两个电感、隔离器组成,第一开关管、第二开关管、第三开关管分别控制三相绕组的工作,其余开关管按照PWM模式并基于一定的约束条件下,直接实现了高发电电压的输出和低励磁电压输出,关键是一套变流系统解决了对励磁电压和发电电压的可调性,使之成为整个发电系统有益的变量,基于此复合性能下,变流系统结构和控制简易,开关管电压应力低；适合于各类动力驱动下各类开关磁阻发电机系统领域应用。(A multivariable switched reluctance generator current transformation system for self-excitation to change excitation voltage to generate voltage is composed of seven switching tubes, a three-phase winding, five diodes, four capacitors, two inductors and an isolator, wherein the first switching tube, the second switching tube and the third switching tube respectively control the three-phase winding to work, and the other switching tubes directly realize the output of high generation voltage and the output of low excitation voltage according to a PWM mode and based on a certain constraint condition; the method is suitable for application in the field of various switched reluctance generator systems under various power drives.)

1. Multivariable switch reluctance generator current transformation system of excitation voltage variation generated voltage, characterized by including: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, a first phase winding, a second phase winding, a third phase winding, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first inductor, a second inductor, and an isolator, wherein the cathode of the first switch tube is connected with one end of the first phase winding and the cathode of the first diode, the cathode of the second switch tube is connected with one end of the second phase winding and the cathode of the second diode, the cathode of the third switch tube is connected with one end of the third phase winding and the cathode of the third diode, the anode of the first switch tube is connected with the anode of the second switch tube, the anode of the third switch tube, and the output positive end of the isolator, the other end of the first phase winding is connected with the other end of the second phase winding, the other end of the third phase winding, the output negative end of the isolator, one end of the first capacitor and one end of the first inductor, the anode of the first diode is connected with the anode of the second diode, the anode of the third diode, the other end of the first capacitor, the cathode of the fifth diode and the cathode of the seventh switch tube, the other end of the first inductor is connected with the anode of the fourth switch tube and the anode of the fourth diode, the cathode of the fourth switch tube is connected with the anode of the fifth switch tube and one end of the second inductor, the cathode of the fourth diode is connected with one end of the second capacitor, the cathode of the fifth switch tube is connected with the other end of the second capacitor, one end of the third capacitor and the anode of the sixth switch tube, and the cathode of the sixth switch tube is connected with the anode of the seventh switch tube, one end, the other end of the second inductor is connected with the other end of the fourth capacitor and the input positive end of the isolator, and the other end of the third capacitor is connected with the anode of the fifth diode;

the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube are all full-control power electronic switching devices with anti-parallel diodes.

2. The method for controlling the multivariable switched reluctance generator converter system with the self-excitation voltage generation voltage as claimed in claim 1, wherein during the operation of the switched reluctance generator, according to the position information of the rotor, when the first phase winding needs to be put into operation, the first switching tube is closed, the first phase winding enters the excitation stage, and the excitation power supply output by the isolator charges and excites the first phase winding; disconnecting the first switching tube when the to-be-excited stage is finished according to the rotor position information, and entering a power generation stage;

when a second phase winding and a third phase winding need to be put into operation according to the rotor position information, the second switching tube and the third switching tube correspond to the first switching tube, and the operation mode is the same as that of the first phase winding;

when the switched reluctance generator operates, the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube switch according to a PWM mode, the switching frequency is the same, the duty ratios of the fourth switching tube and the seventh switching tube are the same, the phase difference is 180 degrees, the duty ratios of the fifth switching tube and the sixth switching tube are the same, the phase difference is 180 degrees, the switching phase difference of the fourth switching tube and the fifth switching tube is larger than zero, the duty ratio a of the fourth switching tube and the seventh switching tube is larger than 0.5, the duty ratio b of the fifth switching tube and the sixth switching tube also meets the condition that 2-a-b is smaller than 1, and the sizes of the excitation power supply voltage and the generated voltage output after the second capacitor and the third capacitor are connected in series can be adjusted by adjusting the switching duty ratios of the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube under the constraint condition of the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube.

Technical Field

The invention relates to the field of switched reluctance motor systems, in particular to a switched reluctance generator current transformation system which has self excitation, excitation reduction, strong excitation, excitation voltage raising, power generation voltage changing and power generation voltage changing functions and has a switching tube with low voltage stress and a control method thereof.

Background

The switched reluctance motor has the advantages of simple structure, low cost, high reliability and strong fault tolerance, and is more and more valued by the industry.

Compared with the traditional generator, the switched reluctance generator has certain cost advantage, but the requirement of a variable flow control system is higher.

In the operation of the switched reluctance generator, each phase winding is put into operation at different time according to the relative position relation between a stator and a rotor, each phase winding is generally divided into two major phases of excitation and power generation during operation and is carried out at different time, the excitation phase is provided with electric energy by an external power supply, a separate excitation mode in which a separate excitation power supply supplies power and a self-excitation mode in which self-generated electric energy is utilized for excitation are generally adopted, and in order to take the advantages of the separate excitation mode and the self-excitation mode into consideration, the decoupling type self-excitation mode becomes one of the development trends, so that great interference cannot be caused to the power generation output side during excitation.

In the conventional switched reluctance generator, in order to realize the output of higher power, namely more electric energy, and in accordance with other needs of the system, two regulation and control modes of phase winding switching angle regulation and excitation current chopping control are often adopted, in the development of the switched reluctance generator system, the two regulation and control modes are more and more obvious, other regulation and control variables are urgently required to be developed, and variable excitation voltage control is generated, because the variable excitation voltage is necessary to take the strengthening excitation function which is very much in mind in the industry into consideration, however, when the conventional phase winding current conversion loop is adopted, because of the phase winding and the operation characteristics thereof of the switched reluctance generator, the output voltage when the phase winding is discharged and output is often greater than the excitation voltage in the previous stage, that is, if the self-excitation decoupling mode is adopted for excitation, the variable excitation voltage excitation is considered on the basis of voltage reduction, such modes are very rare at present, or a voltage reduction device is required to be added before the excitation is changed, so that the cost and the complexity of the structure are increased, and the reliability is reduced.

According to the mathematical model of the switched reluctance generator, the relationship between the motion electromotive force and the generated voltage of the switched reluctance generator during operation determines the trend of the phase winding current after entering the phase winding generating stage, if the phase current rises, the electric energy output by the generator is increased, otherwise, the electric energy output by the generator is reduced, namely, the problems of generating efficiency and benefit are directly concerned, which is a big problem, but in some fields or working conditions, the movement electromotive force is restricted by other factors and can not be adjusted randomly, since this is also directly related to the switched reluctance generator speed, which is a big problem in maximum power output control, for the generated voltage, it is often difficult to control and vary at present, however, if the generated voltage can be adjusted and changed, the movement electromotive force is not changed according to the working condition of the system in operation, the generated voltage is adjusted, so that the same effect of changing the motion electromotive force without changing the generated voltage is achieved; on the other hand, in the whole power generation field, including the power generation field of the switched reluctance generator certainly, the electric energy voltage which is directly generated by the switched reluctance generator is often too low, namely, the generated voltage is too low to meet the requirement of a load side or grid connection, and then an independent boosting device is needed to be added.

Of course, the power electronic switch tube also presents challenges based on the larger generation voltage requirement, and the key is the voltage stress problem of the required switch tube, and if the voltage stress is too large, some problems are caused.

The more performance is realized, the more complex structure and the more complicated control are brought, the reliability is reduced, the cost is improved, and the cost performance is also a problem, so the more simple structure and control on the basis of the performance are development tendency.

Disclosure of Invention

According to the background technology, the invention provides the switched reluctance generator current transformation system which directly increases the power generation voltage and outputs the reduced strong excitation voltage in self-excitation and power generation, particularly can adjust the power generation voltage and the excitation voltage in the process, further brings two adjustable variables for the system and has a simple structure, and the control method thereof.

The technical scheme of the invention is as follows:

multivariable switch reluctance generator current transformation system of excitation voltage variation generated voltage, characterized by including: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, a first phase winding, a second phase winding, a third phase winding, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first inductor, a second inductor, and an isolator, wherein the cathode of the first switch tube is connected with one end of the first phase winding and the cathode of the first diode, the cathode of the second switch tube is connected with one end of the second phase winding and the cathode of the second diode, the cathode of the third switch tube is connected with one end of the third phase winding and the cathode of the third diode, the anode of the first switch tube is connected with the anode of the second switch tube, the anode of the third switch tube, and the output positive end of the isolator, the other end of the first phase winding is connected with the other end of the second phase winding, the other end of the third phase winding, the output negative end of the isolator, one end of the first capacitor and one end of the first inductor, the anode of the first diode is connected with the anode of the second diode, the anode of the third diode, the other end of the first capacitor, the cathode of the fifth diode and the cathode of the seventh switch tube, the other end of the first inductor is connected with the anode of the fourth switch tube and the anode of the fourth diode, the cathode of the fourth switch tube is connected with the anode of the fifth switch tube and one end of the second inductor, the cathode of the fourth diode is connected with one end of the second capacitor, the cathode of the fifth switch tube is connected with the other end of the second capacitor, one end of the third capacitor and the anode of the sixth switch tube, and the cathode of the sixth switch tube is connected with the anode of the seventh switch tube, one end, the other end of the second inductor is connected with the other end of the fourth capacitor and the input positive end of the isolator, and the other end of the third capacitor is connected with the anode of the fifth diode;

the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube are all full-control power electronic switching devices with anti-parallel diodes.

The control method of the multivariable switch reluctance generator current transformation system of the self-excitation variable excitation voltage generation voltage is characterized in that when a first phase winding needs to be put into operation according to the position information of a rotor in the operation of the switch reluctance generator, a first switch tube is closed, an excitation stage is started, and an excitation power supply output by an isolator charges and excites the first phase winding; disconnecting the first switching tube when the to-be-excited stage is finished according to the rotor position information, and entering a power generation stage;

when a second phase winding and a third phase winding need to be put into operation according to the rotor position information, the second switching tube and the third switching tube correspond to the first switching tube, and the operation mode is the same as that of the first phase winding;

when the switched reluctance generator operates, the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube switch according to a PWM mode, the switching frequency is the same, the duty ratios of the fourth switching tube and the seventh switching tube are the same, the phase difference is 180 degrees, the duty ratios of the fifth switching tube and the sixth switching tube are the same, the phase difference is 180 degrees, the switching phase difference of the fourth switching tube and the fifth switching tube is larger than zero, the duty ratio a of the fourth switching tube and the seventh switching tube is larger than 0.5, the duty ratio b of the fifth switching tube and the sixth switching tube also meets the condition that 2-a-b is smaller than 1, and the sizes of the excitation power supply voltage and the generated voltage output after the second capacitor and the third capacitor are connected in series can be adjusted by adjusting the switching duty ratios of the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube under the constraint condition of the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube.

The invention has the following main technical effects:

under the structure and control of the invention, the high generating voltage output and the self-excitation magnetic-reducing excitation voltage output are realized by using the same system, and on the basis, the excitation voltage and the generating voltage can be adjusted by adjusting the duty ratios of the fourth switching tube, the fifth switching tube, the sixth switching tube and the seventh switching tube, so that the multiple functions of high generating voltage, variable generating voltage, self-excitation, voltage-reducing excitation and variable excitation voltage are completed, and the relative number of the switching tubes and the control complexity are simpler.

Meanwhile, the voltage stress of all the switch tubes is far smaller than the power generation voltage, so that the cost is reduced and the reliability is improved.

Drawings

Fig. 1 is a circuit structure diagram of a multivariable switch reluctance generator current transformation system for self-excitation voltage generation voltage.

Detailed Description

The multivariable switched reluctance generator converter system for self-excitation voltage generation voltage of the present embodiment is shown in fig. 1, and comprises a first switching tube V1, a second switching tube V2, a third switching tube V3, a fourth switching tube V4, a fifth switching tube V5, a sixth switching tube V6, a seventh switching tube V7, a first phase winding M, a second phase winding N, a third phase winding P, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a first inductor L1, a second inductor L2, and an isolator, wherein the cathode of the first switching tube V1 is connected to one end of the first phase winding M and the first diode D5, the cathode of the second switching tube V2 is connected to one end of the first diode D57324 and the cathode of the second diode V5857324, the cathode of the third switching tube V3 is connected with one end of a third phase winding P and the cathode of a third diode D3, the anode of the first switching tube V1 is connected with the anode of the second switching tube V2, the anode of the third switching tube V3 and the anode end of an isolator output, the other end of the first phase winding M is connected with the other end of the second phase winding N, the other end of the third phase winding P, the anode end of an isolator output, one end of a first capacitor C1 and one end of a first inductor L1, the anode of the first diode D1 is connected with the anode of a second diode D2, the anode of a third diode D3, the other end of the first capacitor C1, the cathode of a fifth diode D5 and the cathode of a seventh switching tube V7, the other end of the first inductor L1 is connected with the anode of a fourth switching tube V4 and the anode of a fourth diode D4, the cathode of the fifth switching tube V4 is connected with the anode of a fifth switching tube V5 and one end of the fourth diode V4, the cathode of the fourth diode D4 is connected with one, One end of a third capacitor C3 and the anode of a sixth switching tube V6, the cathode of the sixth switching tube V6 is connected with the anode of a seventh switching tube V7, one end of a fourth capacitor C4 and the input negative end of an isolator, the other end of a second inductor L2 is connected with the other end of a fourth capacitor C4 and the input positive end of the isolator, and the other end of the third capacitor C3 is connected with the anode of a fifth diode D5;

the fourth switching tube V4, the fifth switching tube V5, the sixth switching tube V6 and the seventh switching tube V7 are all full-control high-frequency power electronic switching devices with anti-parallel diodes, such as IGBTs, power MOSFETs and the like; the two output ends of the isolator are the output ends of the excitation power supply, namely the excitation voltage; the two ends of the second capacitor C2 and the third capacitor C3 after being connected in series, namely, the space between the cathode of the fourth diode D4 and the anode of the fifth diode D5 is the power generation output end, namely, the power generation voltage.

The invention discloses a control method of a multivariable switch reluctance generator current transformation system for self-excitation variable excitation voltage generation voltage, which comprises the following steps: when the switched reluctance generator operates, according to the position information of the rotor, when the first phase winding M needs to be put into operation, the first switching tube V1 is closed, the first phase winding M enters an excitation stage, an excitation power supply output by the isolator charges and excites the first phase winding M, and the voltage at two ends of the first phase winding M is equal to the excitation voltage (the tube voltage drop is ignored); when the excitation waiting phase is finished according to the rotor position information, the first switching tube V1 is disconnected, and the power generation phase is started, at this time, the stored energy of the first phase winding M is discharged to the first capacitor C1 side through the first diode D1 and is output through the first inductor L1;

when the second phase winding N and the third phase winding P need to be put into operation according to the rotor position information, the second switching tube V2 and the third switching tube V3 correspond to the first switching tube V1, the second diode D2 and the third diode D3 correspond to the first diode D1, other devices are shared, and the operation mode is the same as that of the first phase winding M;

in the operation of the switched reluctance generator, the fourth switch tube V4, the fifth switch tube V5, the sixth switch tube V6 and the seventh switch tube V7 switch and operate according to the PWM mode, and the switching frequencies are the same, in fact, as can be seen from the circuit structure of the present invention, after the power generation stage passes through the first capacitor C1 and the first inductor L1, when the output is output to the second capacitor C2 and the third capacitor C3, the circuit is similar to the BOOST structure, and when the output is output to the isolator, the circuit is similar to the BUCK structure, considering the need of obtaining high power generation voltage, and according to the mathematical model principle of the switched reluctance generator, in practice, the output voltage of the phase winding after directly generating power is higher than the excitation voltage, that is, the voltage on both sides of the first capacitor C1 is generally higher than the practical need of the isolator output excitation voltage, so, in order to ensure that both the output of high power generation voltage and the excitation voltage are reduced, each switching tube (fourth switching tube V4, fifth switching tube V5, sixth switching tube V6 and seventh switching tube V7) of the self-excitation and boost hybrid integrated circuit of the invention also needs to satisfy the following control conditions: the fourth switching tube V4 and the seventh switching tube V7 have the same duty ratio and are 180 degrees out of phase, the fifth switching tube V5 and the sixth switching tube V6 have the same duty ratio, and the phase difference is 180 degrees, the switching phase difference between the fourth switching tube V4 and the fifth switching tube V5 is greater than zero degrees, the duty ratio a of the fourth switching tube V4 and the seventh switching tube V7 is greater than 0.5, the duty ratio b of the fifth switching tube V5 and the sixth switching tube V6 also meets the condition that 2-a-b is less than 1, and the sizes of the excitation voltage and the generating voltage can be adjusted by adjusting the switching duty ratios of the fourth switching tube V4, the fifth switching tube V5, the sixth switching tube V6 and the seventh switching tube V7 under the constraint condition, therefore, the regulation and the change of the excitation voltage and the generation voltage within the required range are realized by one set of current transformation loop, and two adjustable variables are added in the whole switched reluctance generator system.

It can be seen from the structure and control of the current transformation system of the invention that for other switched reluctance generators with non-three-phase windings, the problem that the series branch of the added or deleted winding and a switching tube is not present in the structure is solved, and the control method is the same, so the structure and control of the invention have protection rights for the switched reluctance generators with any number of phase windings.