阅读说明：本技术 一种整流器控制电路 (Rectifier control circuit ) 是由 马东 李阳 吴春瑜 刘世超 刘洋 杨帅飞 靳洋 赵嘉伟 于 2020-12-14 设计创作，主要内容包括：本发明公开了一种整流器控制电路,所述控制电路包括：主功率电路模块、锁相环模块、坐标变换模块、预测模块以及价值优化模块；所述预测模块、所述价值优化模块以及所述主功率电路模块顺次连接；所述主功率电路模块、电感以及所述锁相环模块顺次连接；所述坐标变换模块的第一端连接在所述锁相环模块与所述电感之间的通路上,所述坐标变换模块的第二端连接所述预测模块,所述坐标变换模块的第三端连接在所述主功率电路模块与所述电感的通路上。本发明公开的整流器控制电路,能够有效解决空间交流母线架构中交流频率波动与交流侧电流谐波分量较多的问题。(The invention discloses a rectifier control circuit, which comprises: the device comprises a main power circuit module, a phase-locked loop module, a coordinate transformation module, a prediction module and a value optimization module; the prediction module, the value optimization module and the main power circuit module are connected in sequence; the main power circuit module, the inductor and the phase-locked loop module are sequentially connected; the first end of the coordinate transformation module is connected to a path between the phase-locked loop module and the inductor, the second end of the coordinate transformation module is connected to the prediction module, and the third end of the coordinate transformation module is connected to a path between the main power circuit module and the inductor. The rectifier control circuit disclosed by the invention can effectively solve the problems of alternating current frequency fluctuation and more alternating current side current harmonic components in a space alternating current bus structure.)

1. A rectifier control circuit, the control circuit comprising: the device comprises a main power circuit module, a phase-locked loop module, a coordinate transformation module, a prediction module and a value optimization module;

the prediction module, the value optimization module and the main power circuit module are connected in sequence;

the main power circuit module, the inductor and the phase-locked loop module are sequentially connected;

the first end of the coordinate transformation module is connected to a path between the phase-locked loop module and the inductor, the second end of the coordinate transformation module is connected to the prediction module, and the third end of the coordinate transformation module is connected to a path between the main power circuit module and the inductor.

2. The control circuit of claim 1, wherein the main power circuit module comprises: the circuit comprises a first bridge circuit branch, a second bridge circuit branch, a third bridge circuit branch, a first switch, a second switch, a third switch, a first filter capacitor, a second filter capacitor, a load and a power supply, wherein each bridge circuit branch comprises two diodes and an inductor.

3. The control circuit of claim 1, wherein the first switch, the second switch, and the third switch are all bidirectional power switching tubes.

4. The control circuit of claim 1, wherein the first filter capacitor and the second filter capacitor are output voltage dividing capacitors with the same capacity, and the voltage of the first filter capacitor and the voltage of the second filter capacitor are both half of the output voltage.

5. The control circuit of claim 1, wherein the phase-locked loop module is configured to: and determining the voltage angle of the alternating current side according to the acquired voltage.

6. The control circuit of claim 1, wherein the coordinate transformation module is configured to:

3/2 transformation is carried out on the three-phase voltage to obtain a voltage signal under a two-phase static coordinate system;

3/2 transformation is carried out on the three-phase current, so that a current signal under a two-phase static coordinate system is obtained.

7. The control circuit of claim 1, wherein the prediction module is configured to:

and predicting the current dynamic behavior under the action of different voltage vectors at the next moment.

8. The control circuit of claim 1, wherein the value optimization module is configured to:

evaluating and optimizing the prediction result of the prediction module through a cost function;

and selecting an optimal switching state, and determining a control signal of the power switch at the next moment according to the optimal switching state.

Technical Field

The invention belongs to the technical field of space alternating current-direct current conversion, and particularly relates to a rectifier control circuit.

Background

With the rapid development of aerospace technology and space science, the means for human to know the universe is more and more abundant, the earth, the moon, the sun and the sun major system research are developed, the solar system marginal detection is carried out, and the method becomes an important direction for human aerospace activities. With the increasing difficulty of the demand of deep space exploration tasks, the design requirements of a spacecraft power supply system are more rigorous. On the premise of ensuring high reliability and high power density of a power supply system, the distributed power supply system based on the alternating-current bus architecture gradually draws attention of people in order to reduce bus current and cable power loss of the power supply system. The high-voltage alternating-current bus power supply system inevitably has large harmonic interference, and a large amount of harmonic current brings great difficulty to the design of the power supply system and influences the reduction of the conversion efficiency and the power supply quality of the power supply system. Meanwhile, the frequency of the high-voltage alternating-current bus fluctuates to a certain extent, and the high-voltage alternating-current bus causes great damage to a rear-stage power conversion device, so that the reliability of a spacecraft power supply system is greatly reduced. The VIENNA rectifier realizes that the waveform of input current strictly tracks the waveform of input voltage through a control circuit, thereby achieving the purposes of inhibiting harmonic current and improving power factor.

The fluctuation of the output frequency of the distributed power system based on the alternating-current bus architecture is considered, and the serious influence is brought to the safe operation of the spacecraft power system. When the system frequency fluctuates, the alternating-current side angular frequency has certain uncertainty, so that phase difference exists in three-phase alternating-current voltage input, and three-phase voltage unbalance is caused; the output voltage fluctuation is serious due to the change of the excitation current of the generator and the transformer and the increase of the consumed reactive power. On the other hand, the more unstable the frequency, the more severe the distortion, thereby reducing the power factor of the system; meanwhile, input current ripples are severe, thereby causing an increase in loss. As power system power increases, the switching devices of boost PFC converters are necessarily subject to excessive voltage and current stresses.

Compared with the traditional bridge PWM rectifier, the three VIENNA rectifiers belong to Boost type power factor correction, the inductive current is continuous in a normal working mode, the input current is sinusoidal, and the distortion rate is low, so that the unit power factor operation of the rectifier can be realized; the voltage stress of the switching tube is only half of the voltage of the direct-current bus, the switching loss is smaller under the same power, the efficiency can be improved to a certain degree, and the high-power direct-current bus-bar switch is more suitable for high-power occasions; the topology does not contain an active bridge arm, the bridge arm direct connection risk is avoided, and extra dead zones are not required to be arranged. The Vienna rectifier is of a three-level structure, so that the control is more flexible, and the total harmonic distortion is greatly reduced, so that the numerical value and the volume of a passive device can be reduced, and the power density of a system is improved; the jump of the voltage is small, and the current ripple of the inductor is reduced under the same switching frequency, so that the size of the inductor is reduced, and the power density of the rectifier is improved.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the problem of more alternating current frequency fluctuation and alternating current side current harmonic components in a space alternating current bus structure.

In order to solve the above technical problem, the present invention discloses a rectifier control circuit, wherein the control circuit includes: the device comprises a main power circuit module, a phase-locked loop module, a coordinate transformation module, a prediction module and a value optimization module;

the prediction module, the value optimization module and the main power circuit module are connected in sequence;

the main power circuit module, the inductor and the phase-locked loop module are sequentially connected;

the first end of the coordinate transformation module is connected to a path between the phase-locked loop module and the inductor, the second end of the coordinate transformation module is connected to the prediction module, and the third end of the coordinate transformation module is connected to the main power circuit module on the path of the inductor.

Optionally, the main power circuit module includes: the circuit comprises a first bridge circuit branch, a second bridge circuit branch, a third bridge circuit branch, a first switch, a second switch, a third switch, a first filter capacitor, a second filter capacitor, a load and a power supply, wherein each bridge circuit comprises two diodes and an inductor.

Optionally, the first switch, the second switch and the third switch are all bidirectional power switching tubes.

Optionally, the first filter capacitor and the second filter capacitor are output voltage-dividing capacitors with the same capacity, and the voltage of the first filter capacitor and the voltage of the second filter capacitor are both half of the output voltage.

Optionally, the phase-locked loop module is configured to: and determining the voltage angle of the alternating current side according to the acquired voltage.

Optionally, the coordinate transformation module is configured to:

3/2 transformation is carried out on the three-phase voltage to obtain a voltage signal under a two-phase static coordinate system;

3/2 transformation is carried out on the three-phase current, so that a current signal under a two-phase static coordinate system is obtained.

Optionally, the prediction module is configured to:

and predicting the current dynamic behavior under the action of different voltage vectors at the next moment.

Optionally, the value optimization module is configured to:

evaluating and optimizing the prediction result of the prediction module through a cost function;

and selecting an optimal switching state, and determining a control signal of the power switch at the next moment according to the optimal switching state.

Compared with the prior art, the invention has the following advantages:

the rectifier control circuit provided by the embodiment of the application comprises a main power circuit module, a phase-locked loop module, a coordinate transformation module, a prediction module and a value optimization module; the model self-correction prediction control algorithm based on the control circuit is simple and has small operand, and the response speed of the control system is ensured. When the parameters of the control object model are not matched, the control algorithm has stronger robustness, and can greatly improve the power factor of the space rectifier module, thereby improving the efficiency of the power supply system. For an alternating current bus system with high space power, the control algorithm is favorable for self-adapting to parameter change of an alternating current side, the dynamic response capability of a power supply system can be improved, the urgent intelligent requirements of a space vehicle on a power supply control module are met, and the problems of alternating current frequency fluctuation and more alternating current side current harmonic components in a space alternating current bus structure can be effectively solved.

Drawings

Fig. 1 is a simple circuit diagram of a rectifier control circuit provided in the present invention;

FIG. 2 is a simplified topology circuit diagram of a three-phase VIENNA rectifier provided by the present invention;

fig. 3 is a schematic diagram of a rectifier control circuit provided by the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Fig. 1 is a schematic circuit diagram of a rectifier control circuit according to an embodiment of the invention.

The rectifier control circuit provided by the embodiment of the application is suitable for any appropriate type of rectifier, such as: a space high-power three-phase three-level VIENNA rectifier. As shown in fig. 1, the rectifier control circuit includes a main power circuit module 101, a Phase Locked Loop (PLL) module, a coordinate transformation module abc → α β module, a prediction module, and a value optimization module.

The prediction module, the value optimization module and the main power circuit module are sequentially connected; the main power circuit module, the inductor and the phase-locked loop module are sequentially connected; the first end of the coordinate transformation module is connected to a path between the phase-locked loop module and the inductor, the second end of the coordinate transformation module is connected to the prediction module, and the third end of the coordinate transformation module is connected to a path between the main power circuit module and the inductor.

The phase-locked loop module is used for: and determining the voltage angle of the alternating current side according to the acquired voltage.

The coordinate transformation module is to: 3/2 transformation is carried out on the three-phase voltage to obtain a voltage signal under a two-phase static coordinate system; 3/2 transformation is carried out on the three-phase current, so that a current signal under a two-phase static coordinate system is obtained.

The prediction module is to: and predicting the current dynamic behavior under the action of different voltage vectors at the next moment.

The value optimization module is used for: evaluating and optimizing the prediction result of the prediction module through a cost function; and selecting an optimal switching state, and determining a control signal of the power switch at the next moment according to the optimal switching state.

In an alternative embodiment, the main power circuit module comprises: the circuit comprises a first bridge circuit branch, a second bridge circuit branch, a third bridge circuit branch, a first switch, a second switch, a third switch, a first filter capacitor, a second filter capacitor, a load and a power supply, wherein each bridge circuit comprises two diodes and an inductor. In addition, the main power circuit module collects the alternating-current side voltage and the input current in the system operation process.

The first switch, the second switch and the third switch are all bidirectional power switch tubes. The first filter capacitor and the second filter capacitor are output voltage-dividing capacitors with the same capacity, and the voltage of the first filter capacitor and the voltage of the second filter capacitor are half of the output voltage.

Referring to fig. 2 to 3, a three-phase VIENNA rectifier will be described as an example in which the finisher control circuit according to the embodiment of the present invention is applied.

Fig. 2 is a simplified topology circuit diagram of a three-phase VIENNA rectifier. The three-phase VIENNA rectifier corresponds to the main power circuit block shown in fig. 1.

As shown in fig. 2, the simplified topology circuit of the three-phase VIENNA rectifier includes: la, Lb and Lc are input filter inductors with equal inductance values; d1, D2, D3, D4, D5 and D6 are high-power fast recovery diodes, and an upper fast recovery diode and a lower fast recovery diode form a bridge arm; sa, Sb and Sc are bidirectional power switching tubes, and each bidirectional power switching tube consists of two switching power devices; c1 and C2 are output voltage-dividing capacitors with equal capacity, and the voltage is half of the output voltage. Active power flows from the AC side to the DC side in a single direction, and reactive power flows on the AC side. In the three-phase VIENNA circuit, alternating current flows into a power part of the VIENNA circuit through an input filter inductor, an output capacitor adopted at the direct current side of a rectifier divides the voltage, the three-level output effect is achieved, and meanwhile output voltage ripples can be reduced.

In fig. 2, one bridge arm and one input filter inductor form one bridge circuit branch.

Fig. 3 is a circuit diagram of a rectifier control circuit modified based on the control requirements for a three-phase VIENNA rectifier. The rectifier control circuit may also be referred to as a model self-correcting predictive control circuit. The control circuit adopts a PI controller to control the voltage of a direct current bus and provides a d-axis current reference value. To achieve unity power factor operation of the system, the q-axis current reference value is set to 0. And carrying out coordinate transformation on the d-axis current reference value and the q-axis current reference value to obtain a current reference value in a two-phase static coordinate system. And compensating the inductance parameter L0 measured by the observer into the current prediction model to obtain a modified current prediction model. And according to a model prediction control principle, the acquired real-time voltage and current signals pass through a corrected current prediction model, and the optimal switching state is obtained by utilizing a value function and is used as a control signal of the power switch at the next moment.

Wherein the area enclosed by the dashed line in fig. 3 corresponds to the circuit portion of the active power circuit block in fig. 2, and is based on the specific application scenario for the mainThe circuit part of the power circuit module is adapted. For example: integrating the bidirectional power switch tube and the bridge arm in three bridge circuit branches to S in FIG. 3_kAnd (4) a module part.

The rectifier control circuit provided by the embodiment of the application has the advantages that the model self-correction prediction control algorithm is simple, the operand is small, and the response speed of a control system is guaranteed. When the parameters of the control object model are not matched, the control algorithm has stronger robustness, and can greatly improve the power factor of the space rectifier module, thereby improving the efficiency of the power supply system. For an alternating current bus system with high space power, the control algorithm is favorable for self-adapting to parameter change of an alternating current side, the dynamic response capability of a power supply system can be improved, the urgent intelligent requirements of a space vehicle on a power supply control module are met, and the problems of alternating current frequency fluctuation and more alternating current side current harmonic components in a space alternating current bus structure can be effectively solved.

It should be noted that the above description is only a preferred embodiment of the present invention, and it should be understood that various changes and modifications can be made by those skilled in the art without departing from the technical idea of the present invention, and these changes and modifications are included in the protection scope of the present invention.

The embodiments in the present description are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The above description is only for the best mode of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Those skilled in the art will appreciate that the details of the invention not described in detail in this specification are well within the skill of those in the art.