Feedback type land joint debugging multifunctional electronic load system and control method thereof

Abstract

The invention belongs to the technical field of land joint debugging tests of ship power systems, and particularly discloses a feedback type land joint debugging multifunctional electronic load system and a control method thereof, and the system comprises a load simulation and feedback main circuit, a detection module and a control module. The control method includes inputting an expected load power factor; acquiring a three-phase power supply and a three-phase current of the system, and performing coordinate system transformation to obtain voltage and current vectors under a two-phase rotating coordinate system; generating target voltage and current vectors under a two-phase rotating coordinate system according to an expected load power factor; voltage and current vectors are compared, PI adjustment, feedforward decoupling and coordinate inverse transformation are carried out; and generating an SVPWM control signal to control a main circuit to work. The device can be used as a detection device in a joint debugging test field, is used for simulating load conditions of different ships under different working conditions, and also can be used as a direct-current and alternating-current power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of onshore joint debugging test of a ship power system, and in particular to a feedback-type onshore joint debugging multifunctional electronic load system and a control method thereof. Background Art

[0002] As ships develop towards intelligence, integration, and green environmental protection, the complexity of ship electrical equipment has also increased. In order to shorten the ship construction period, improve the efficiency and success rate of mooring tests, and ensure the smooth progress of sea trials, it is of great significance to conduct onshore joint debugging of ship electrical equipment. However, during the test, energy-consuming loads such as water resistors are often used for testing, which consumes a large amount of electrical energy in the form of heat. In addition, during the test, most reactive loads can only be adjusted in steps and cannot accurately simulate all working conditions of the ship during navigation.

[0003] In the context of promoting "carbon peak and carbon neutrality", if the electricity generated by the unit under test cannot be effectively used, the generated electricity will be consumed in vain, resulting in a huge waste of resources. At the same time, the carbon dioxide and atmospheric pollutants generated will affect the air quality of the test site. In addition, the power factor of the existing load system with water resistors and reactors cannot be accurately adjusted, and the equipment status under all working conditions cannot be obtained. If the corresponding load system is configured according to each ship and each working condition, the economy is poor and does not conform to the actual situation.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problems existing in the background technology. To this end, a feedback-type onshore joint-adjustment multifunctional electronic load system and a control method thereof are provided, wherein the multifunctional electronic load system is a multifunctional, modular, low-carbon and environmentally friendly power factor adjustable load, which can be used as a detection load of a test equipment and as an AC / DC power supply; the phase and amplitude of the voltage and current collected by the sensor can be adjusted by the control module to smoothly change the power factor of the electronic load and increase the application scenarios of the load; it can also be controlled by the SVPWM signal of the control module to output the required DC and AC voltages for powering other equipment or being incorporated into the power grid to achieve efficient utilization of electrical energy.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A feedback-type onshore joint-adjustment multifunctional electronic load system, comprising a load simulation and feedback main circuit, a detection module and a control module;

[0008] The load simulation and feedback main circuit includes an input filter, a load simulation module, a buck-boost chopper module, an inverter module and an output filter;

[0009] The output end of the input filter is electrically connected to the input end of the load simulation module, the output end of the load simulation module is electrically connected to the input end of the buck-boost chopper module, the output end of the buck-boost chopper module is electrically connected to the input end of the inverter module, and the output end of the inverter module is electrically connected to the input end of the output filter;

[0010] The detection module includes an input voltage detection module, an input current detection module and an output voltage and current detection module;

[0011] The input end of the input voltage detection module is electrically connected to the input end of the input filter, the input end of the input current detection module is electrically connected to the output end of the input filter and the output end of the input voltage detection module, and the input end of the output voltage and current detection module is electrically connected to the output end of the output filter;

[0012] The output end of the input voltage detection module, the output end of the input current detection module and the output end of the output voltage and current detection module are all electrically connected to the control module;

[0013] The load simulation module, the buck-boost chopper module and the inverter module are all electrically connected to the control module.

[0014] The following is a technical solution further defined by the system in the present invention, wherein the input end of the input filter is connected to a three-phase power supply.

[0015] The following is a technical solution further defined by the system in the present invention, wherein the load simulation module is configured as a three-phase full-bridge rectifier circuit, and the inverter module is configured as a three-phase full-bridge inverter circuit.

[0016] A method for controlling an electronic load system based on the above-mentioned feedback-type onshore joint debugging multifunctional electronic load system comprises the following steps:

[0017] Step S1: input the desired load power factor;

[0018] Step S2: Collect the three-phase power supply and three-phase current of the system;

[0019] Step S3: performing coordinate transformation on the voltage and current collected in step S2 to obtain voltage and current vectors in a two-phase rotating coordinate system;

[0020] Step S4: generating target voltage and current vectors in a two-phase rotating coordinate system according to the load power factor expected in step S1;

[0021] Step S5: Compare the voltage and current vectors of step S3 and step S4;

[0022] Step S6: performing PI adjustment on the comparison result obtained in step S5;

[0023] Step S7: performing feedforward decoupling according to the adjustment parameters obtained in step S6;

[0024] Step S8: performing coordinate inverse transformation on the voltage parameters obtained by decoupling in step S7;

[0025] Step S9: generating a SVPWM control signal;

[0026] Step S10: Output a control signal to control the operation of the main circuit.

[0027] The following is a technical solution further defined by the method of the present invention. In step S1, the desired load power factor input is a continuously changing power factor.

[0028] The following is a technical solution further limited by the method in the present invention. The three-phase current collected in step S2 is the three-phase current after harmonic elimination.

[0029] The following is a technical solution further defined by the method in the present invention: the three-phase voltage collected in step S2 passes through a phase-locked loop.

[0030] The following is a technical solution further defined by the method of the present invention. In step S3, the coordinate system transformation includes the transformation of three-phase coordinates and two-phase coordinates and the transformation of stationary coordinates and rotating coordinates.

[0031] The following is a technical solution further defined by the method of the present invention. In step S8, the inverse coordinate transformation includes the transformation of rotating coordinates and stationary coordinates and the transformation of two-phase coordinates and three-phase coordinates.

[0032] The following is a technical solution further defined by the method in the present invention. The SVPWM control signal generated in step S9 directly acts on the load simulation module.

[0033] Compared with the prior art, the present invention has the following technical effects:

[0034] The multifunctional electronic load system of the present invention can be used as a detection device in the joint debugging test field, and can also be used as a DC and AC power supply; when it is used as a detection device, it can continuously adjust the power factor to simulate the load conditions of different ships under different working conditions, and can also feed back the detected electric energy to the field power grid to improve the energy utilization efficiency and reduce energy loss, so as to achieve the goals of energy conservation, emission reduction, low carbon and environmental protection; when it is used as a power supply, it can output DC and AC power, and adjust the voltage level according to actual needs.

[0035] The present invention is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art 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.

[0037] Figure 1 is a system connection block diagram of the present invention;

[0038] Figure 2 It is the main circuit structure topology diagram of the system of the present invention;

[0039] Figure 3 It is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0041] like Figure 1-3 As shown, this embodiment provides a feedback-type onshore joint-adjustment multifunctional electronic load system (also called a shore power system) and a control method for the feedback-type onshore joint-adjustment multifunctional electronic load system.

[0042] like Figure 1 and 2 As shown, a feedback-type onshore joint-adjustment multifunctional electronic load system is composed of a load simulation and feedback main circuit, a detection module, a control module, etc. Among them, the main circuit adopts a back-to-back topology structure with an input filter and an output filter, specifically including an input filter, a load simulation module, a buck-boost chopper module, an inverter module, and an output filter.

[0043] The load simulation and feedback main circuit starts from the input, and after passing through the input filter, load simulation module and buck-boost chopper module, a DC power of a specified voltage level can be obtained. After the buck-boost chopper module, it can be fed back to the field power grid through the inverter module and output filter. The detection module includes an input voltage detection module, an input current detection module and an output voltage and current detection module, and its function is to collect the voltage and current of each node in the load simulation and feedback main circuit, and transmit the collected information data to the control module. The control module includes a power factor control module and a voltage control module, which receives signals from the load simulation and feedback main circuit and the detection module, and then transmits the control signal to the load simulation module, the buck-boost chopper module and the inverter module, which is used to adjust the power factor and voltage level of the multifunctional electronic load system. The control module controls the operation of the entire system.

[0044] Input the desired power factor and DC voltage; detect the input voltage, transmit the collected voltage to the control module, and filter the input current; detect the input current, and transmit the collected current to the control module; the control module outputs a control signal to the load simulation module according to the desired power factor, and detects the voltage and current of the load simulation module at the same time; the control module outputs a control signal to the buck-boost chopper module and outputs DC power according to the desired DC voltage, and detects the voltage and current of the buck-boost chopper module at the same time; collect the voltage and current of the field power grid and transmit them to the control module; the control module sends a control signal to the inverter module according to the grid-connected conditions, and detects the voltage and current of the inverter module at the same time; the inverted current passes through the output filter and is connected to the field power grid.

[0045] The three-phase power supply on the input side is connected to the input filter. The input filter is composed of three capacitors C1 and three inductors L1. The three capacitors C1 are connected in a triangle. The triangle capacitor structure is connected to the three-phase power supply. The three-phase outputs of the three-phase power supply are connected to the load simulation module (also called load simulation circuit) through an inductor L1.

[0046] The load simulation circuit is set as a three-phase full-bridge PWM rectifier circuit composed of six MOS tubes. The three-phase output ends of the input filter are respectively connected to two MOS tubes. Specifically: the source of one MOS tube (MOS tube 1) and the drain of another MOS tube (MOS tube 2) are both connected to one output end of the input filter, and at the same time, the drain of MOS tube 1 is connected to the positive pole of the DC bus, and the source of MOS tube 2 is connected to the negative pole of the DC bus.

[0047] A step-up / step-down chopper module (also called a buck-boost chopper circuit) is connected between the positive pole of the DC bus and the negative pole of the DC bus.

[0048] The buck-boost chopper circuit consists of two capacitors, a unidirectional diode, an inductor and a MOS tube. One capacitor is used as the input capacitor Cin of the buck-boost chopper circuit, and its two ends are connected between the positive pole of the DC bus and the negative pole of the DC bus for subsequent detection of the DC side input voltage; the other capacitor is used as the output capacitor Cout of the buck-boost chopper circuit, and its two ends are connected between the positive pole of the DC bus and the negative pole of the DC bus for subsequent detection of the DC side output voltage. The two ends of the inductor are connected between the positive pole of the DC bus and the negative pole of the DC bus. The unidirectional diode and the MOS tube are both set on the line of the positive pole of the DC bus.

[0049] The two ends of the output capacitor Cout are connected to an inverter module (also called an inverter circuit).

[0050] The inverter circuit is composed of six MOS tubes, and the inverter circuit has a three-phase output terminal. The three-phase output terminals of the inverter circuit are respectively connected to two MOS tubes. Specifically: the source of one MOS tube (MOS tube three) and the drain of another MOS tube (MOS tube four) are both connected to an output terminal of the inverter circuit, and at the same time, the drain of MOS tube three is connected to the positive pole of the DC bus, and the source of MOS tube four is connected to the negative pole of the DC bus.

[0051] The three-phase output end of the inverter circuit is connected to the output filter. The output filter is composed of three capacitors C2 and three inductors L2. The three capacitors C2 are connected in a triangle. The three-phase output end of the inverter circuit is connected to the triangle capacitor structure through an inductor L2 respectively, and the output filter outputs three-phase alternating current.

[0052] like Figure 2 As shown, the detection module detects the input voltage of the input filter (i.e., the output voltage of the three-phase power supply), detects the input current of the load simulation circuit (i.e., the output current of the input filter), detects the output voltage of the load simulation circuit (i.e., the DC side input voltage), and detects the output voltage of the buck-boost chopper circuit (i.e., the DC side output voltage).

[0053] In summary, the load simulation and feedback main circuit is divided into three parts. The front-stage circuit is mainly responsible for preprocessing the test power supply and simulating the load. After passing through the input filter, it is then adjusted by the control module, and the PWM rectifier circuit is used to simulate loads with different power factors to achieve the purpose of testing the performance of the test power supply. The middle part is the buck-boost chopper circuit, which is a DC power supply with variable voltage levels. It is controlled by the control module to achieve accurate voltage conversion to meet the requirements of different voltage levels during the test. The back stage is the inverter circuit, whose main function is to invert the chopped DC power into AC power that can be connected to the grid, and finally connected to the field power grid, so as to realize energy feedback and improve energy utilization efficiency.

[0054] A method for controlling an electronic load system based on the above-mentioned feedback-type onshore joint debugging multifunctional electronic load system specifically comprises the following steps:

[0055] Step S1: input the desired load power factor (input controlled by the power factor control module) and the DC voltage (input controlled by the voltage control module). The input desired load power factor is a continuously changing power factor.

[0056] Step S2: Collect the three-phase power supply voltage and three-phase current information of the system, send the collected information data to the control module, and filter the three-phase input current. Therefore, the collected three-phase current is the three-phase current after harmonic elimination, and the collected three-phase voltage passes through a phase-locked loop.

[0057] Step S3: Perform coordinate system transformation on the voltage and current collected in step S2 to obtain the voltage and current vectors in the two-phase rotating coordinate system. The coordinate system transformation includes the transformation between three-phase coordinates and two-phase coordinates and the transformation between stationary coordinates and rotating coordinates.

[0058] Step S4: Generate target voltage and current vectors in a two-phase rotating coordinate system according to the load power factor expected in step S1.

[0059] Step S5: Compare the voltage and current vectors of step S3 and step S4, and calculate the deviations of the reactive component and the active component respectively.

[0060] Step S6: Perform PI adjustment on the comparison result obtained in step S5.

[0061] Step S7: performing feedforward decoupling according to the adjustment parameters obtained in step S6.

[0062] Step S8: Perform an inverse coordinate transformation on the voltage parameter obtained by decoupling in step S7 to obtain a voltage vector in a three-phase rotating coordinate system. The inverse coordinate transformation includes the transformation between rotating coordinates and stationary coordinates and the transformation between two-phase coordinates and three-phase coordinates.

[0063] Step S9: Generate a load power factor SVPWM control signal expected by the electronic load system. The generated SVPWM control signal directly acts on the load simulation module.

[0064] Step 10: The control module outputs the SVPWM control signal to control the operation of the load simulation module in the main circuit.

[0065] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the above disclosed methods and technical contents without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the present invention without departing from the content of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A feedback-type onshore joint-adjustment multifunctional electronic load system, characterized in that: It includes load simulation and feedback main circuit, detection module and control module; The load simulation and feedback main circuit includes an input filter, a load simulation module, a buck-boost chopper module, an inverter module and an output filter; The output end of the input filter is electrically connected to the input end of the load simulation module, the output end of the load simulation module is electrically connected to the input end of the buck-boost chopper module, the output end of the buck-boost chopper module is electrically connected to the input end of the inverter module, and the output end of the inverter module is electrically connected to the input end of the output filter; The detection module includes an input voltage detection module, an input current detection module and an output voltage and current detection module; The input end of the input voltage detection module is electrically connected to the input end of the input filter, the input end of the input current detection module is electrically connected to the output end of the input filter and the output end of the input voltage detection module, and the input end of the output voltage and current detection module is electrically connected to the output end of the output filter; The output end of the input voltage detection module, the output end of the input current detection module and the output end of the output voltage and current detection module are all electrically connected to the control module; The load simulation module, the buck-boost chopper module and the inverter module are all electrically connected to the control module.

2. A feedback-type onshore joint-adjustment multifunctional electronic load system as claimed in claim 1, characterized in that: The input end of the input filter is connected to a three-phase power supply.

3. A feedback-type onshore joint-adjustment multifunctional electronic load system as claimed in claim 1, characterized in that: The load simulation module is configured as a three-phase full-bridge rectifier circuit, and the inverter module is configured as a three-phase full-bridge inverter circuit.

4. An electronic load system control method based on the feedback-type onshore joint debugging multifunctional electronic load system according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step S1: input the desired load power factor; Step S2: Collect the three-phase power supply and three-phase current of the system; Step S3: performing coordinate transformation on the voltage and current collected in step S2 to obtain voltage and current vectors in a two-phase rotating coordinate system; Step S4: generating target voltage and current vectors in a two-phase rotating coordinate system according to the load power factor expected in step S1; Step S5: Compare the voltage and current vectors of step S3 and step S4; Step S6: performing PI adjustment on the comparison result obtained in step S5; Step S7: performing feedforward decoupling according to the adjustment parameters obtained in step S6; Step S8: performing inverse coordinate transformation on the voltage parameters obtained by decoupling in step S7; Step S9: generating a SVPWM control signal; Step S10: Output a control signal to control the operation of the main circuit.

5. The electronic load system control method according to claim 4, characterized in that: The desired load power factor input in step S1 is a continuously changing power factor.

6. The electronic load system control method according to claim 4, characterized in that: The three-phase current collected in step S2 is the three-phase current after harmonics are eliminated.

7. The electronic load system control method according to claim 4, characterized in that: The three-phase voltage collected in step S2 passes through a phase-locked loop.

8. The electronic load system control method according to claim 4, characterized in that: The coordinate system transformation in step S3 includes the transformation between three-phase coordinates and two-phase coordinates and the transformation between stationary coordinates and rotating coordinates.

9. The electronic load system control method according to claim 4, characterized in that: The coordinate inverse transformation in step S8 includes the transformation of rotating coordinates and stationary coordinates and the transformation of two-phase coordinates and three-phase coordinates.

10. The electronic load system control method according to claim 4, characterized in that: The SVPWM control signal generated in step S9 directly acts on the load simulation module.

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