Power supply system load simulation loading control method

Abstract

The invention discloses a load simulation loading control method for a power supply system. Loading is carried out in the mode that a resistive load loads most of load values, and an electronic load loads a small part of dynamic load values. And the requirements of capacity, precision and dynamism are met. The resistive load and the electronic load are physically combined, and the resistive load is mainly used, so that the requirements of capacity and economy are met; and the electronic load is used as an auxiliary material, so that the high-precision and high-dynamic performance requirements are met.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft ground testing, and in particular relates to a load simulation loading control method for a power supply system. Background Art

[0002] There are two main types of load simulation methods for power supply systems: traditional resistive load and electronic load.

[0003] Resistive loads use relays to control the series and parallel connection of different resistors to achieve current changes. The load value is discontinuous, the load position is fixed, and open-loop control is generally used. The equipment has poor continuity and accuracy, and weak dynamic performance, but it is cheap and has considerable economy for high-power loads.

[0004] Electronic loads use closed-loop control to accurately adjust load current by controlling power electronic devices. They have the characteristics of high precision, programmability, excellent dynamics, and diversified control modes. However, they are relatively expensive and less economical for high-power loads. Summary of the invention

[0005] Purpose of the Invention

[0006] In view of the shortcomings of the existing power system load simulation method, the present invention provides a power system load simulation loading control method.

[0007] Inventing technical solutions

[0008] A method for controlling load simulation of a power system load comprises the following steps:

[0009] s1. Get the required load value. If it is different from the last value, proceed to step s2. If it is the same as the last value, exit.

[0010] s2. Load calculation, allocation to resistive load and electronic load: A% of the total capacity of the electronic load is used for allocation. When the loading value does not exceed A% of the total capacity of the electronic load, the electronic load is used directly; when the loading value exceeds A% of the electronic load capacity, the excess part is loaded with a resistive load, and finally the resistive load gear and the electronic load loading value are obtained;

[0011] s3. Resistive load loading, electronic load loading:

[0012] s3.1 For resistive load loading, when the calculated resistive load loading value is not equal to the current actual resistive load loading value, compare the difference between the calculated resistive load adding and unloading gears and the current actual resistive load adding and unloading gears, and add and unload the gears with differences to make the current actual resistive load gear consistent with the calculated resistive load gear; if the calculated resistive load loading value is equal to the current actual resistive load loading value, no action is taken and step 3.2 is entered;

[0013] s3.2 If the calculated electronic load loading value is not equal to the current actual electronic load loading value, then the electronic load is loaded; if the calculated electronic load loading value is equal to the current actual electronic load loading value, then proceed to step s3.3;

[0014] s3.3 Check the resistive load loading command. If the resistive load loading command has not been executed, re-execute it. If it has been executed, proceed to step 3.4.

[0015] s3.4 determines whether the electronic load loading is executed, if not executed, re-executes, if executed, the load loading is completed;

[0016] s4. Load closed loop control:

[0017] s4.1 reads the total load value;

[0018] s4.2 Confirm whether the resistive load is loaded;

[0019] s4.3 read the current resistive load measurement value. When the current resistive load measurement value is greater than the total load value, reduce the resistive load load value. The resistive load load value reduction is equal to the current resistive load measurement value plus the electronic load capacity A% minus the total load value, and then proceed to step s4.2; when the total load value is greater than or equal to the resistive load measurement value, proceed to step s4.4;

[0020] s4.4 Determine whether the total load value - the current resistive load measurement value ≤ the electronic load capacity. If so, adjust the electronic load so that the total load value - the current resistive load measurement value is equal to the electronic load load value, and then load the electronic load; if not, increase the resistive load load value, and the increase in the resistive load load value is equal to the total load value minus the current resistive load measurement value minus the electronic load capacity A%, and then proceed to step s4.2;

[0021] s5: Repeat the process from s1 to s4.

[0022] Preferably, when loading and unloading the resistive load, a large gear is preferably used.

[0023] Preferably, A% is 45%.

[0024] Preferably, in step s3, when a choice is needed between increasing and decreasing the load, priority is given to reducing the load, and when adding and unloading the electronic load and the resistive load, priority is given to adding and unloading the resistive load.

[0025] Preferably, the actual resistive load loading value is measured by a current and voltage measuring module, and the current and voltage measuring module adopts current and voltage sensors.

[0026] Preferably, load calculation, resistive load loading, electronic load loading, and load closed-loop control are performed by a control computer. The control computer can read the measurement values ​​of the current and voltage measurement modules, and the electronic load can receive the loading command of the control computer; the resistive load can receive the loading command of the control computer to control the parallel relationship of the relay switching resistor.

[0027] Preferably, the ratio of resistive load to electronic load is ≥4:1.

[0028] Preferably, the resistive load is based on an initial value of 0.25A at a nominal voltage and is divided into several gears in geometric multiples of 2.

[0029] Preferably, the number of current and voltage acquisition modules is ≮3, and the acquisition range of the current and voltage sensor modules is 1 / 3, 2 / 3 and the full scale of the rated load value of the resistive load box.

[0030] Preferably, the resistive load is in constant resistance mode; the electronic load has a constant resistance mode, a constant current mode, and a constant power mode; the control computer has constant resistance mode, constant current mode, and constant power mode control modes. In the constant resistance mode control mode, the electronic load is set to the constant resistance mode, and the calculated resistive load loading value + the calculated electronic load loading value = the total setting value; in the constant current mode control mode, the electronic load is set to the constant current mode, and the load closed-loop control feedback signal is the measurement value of the current sensor that measures the actual resistive load loading value; in the constant power mode control mode, the electronic load is set to the constant power mode, and the load closed-loop control feedback signal is calculated as P = U*I.

[0031] Advantages of the present invention:

[0032] (1) Physically combine the resistive load and the electronic load, with the resistive load as the main load to meet the capacity and economic requirements, and the electronic load as the auxiliary load to meet the high-precision and high-dynamic performance requirements.

[0033] (2) This method performs real-time load distribution calculation and parameter closed-loop control, distributes the load to resistive load and electronic load, and performs periodic corrections to meet dynamic, high-precision, and programmable loading requirements, effectively meeting the load simulation requirements of the power supply system of test equipment such as aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 To load the control flow graph.

[0035] Figure 2 It is a three-dimensional diagram of the appearance and installation position of the buoy-vertical tail integrated structure of the present invention.

[0036] Figure 3 Calculate the flow chart for load distribution.

[0037] Figure 4 Load the flow chart for resistive and electronic loads.

[0038] Figure 5 This is the load closed-loop control flow chart. DETAILED DESCRIPTION

[0039] The present invention is achieved through the following technical solutions.

[0040] A method for controlling load simulation of a power system load comprises the following steps:

[0041] s1: Get the required load value requirement;

[0042] s2: Load calculation, distribution to resistive load and electronic load;

[0043] s3: resistive load loading, electronic load loading;

[0044] s4: load closed-loop control;

[0045] s5: Repeat the process from s1 to s4.

[0046] In step s1, the load value is updated at a frequency not lower than 2 Hz or the actual cycle time of s1 to s4.

[0047] In step s2, only the current load value is used as input, without referring to the last load value, and the load is distributed according to the principle of giving priority to the large load gear. The specific process is: when selecting the loading / unloading gear of the resistive load, the large gear is used first (the large gear is given priority during the loading / unloading process). The load distribution calculation flow chart is shown in Figure 3 , the electronic load reserves 10% capacity, and takes out half of the 90% capacity (45% of the total capacity) for distribution. When the loading value does not exceed 45% of the electronic load capacity, the electronic load is used directly. When the loading value exceeds 45% of the electronic load capacity, the excess part will be loaded with a resistive load (the gear is selected from large to small). Due to the discreteness of the resistive load, there is a situation where the loading value cannot be fully loaded. The part that cannot be loaded by the resistive load is added to 45% of the electronic load and loaded with the electronic load. Finally, the resistive load gear and the electronic load loading value are obtained.

[0048] In step s3, the add / unload command is sent to the resistive load and the electronic load through the bus. The specific process is: when the load is increased or decreased, the load reduction is given priority; when the electronic load and the resistive load are added or unloaded, the resistive load is given priority. See the logic flow chart Figure 4, first load the resistive load. When the resistive load loading value is not equal to the current resistive load value, first unload the unloaded gear, and then load the added gear. The larger gear is prioritized during loading and unloading. If the calculated resistive load loading value is equal to the current actual resistive load loading value, the resistive load is loaded. If the electronic load loading value is not equal to the current electronic load loading value, the electronic load is loaded. If the electronic load loading value is equal to the current electronic load loading value, the resistive load loading command check is entered in the next step. If the loading command is not executed, it is re-executed. If it is executed, the next step is to determine whether the electronic load loading is executed. If it is not executed, it is re-executed. If it is executed, the load loading is completed.

[0049] In step s4, the actual load value of the resistive load is calculated by feedbacking the collected values ​​of the voltage sensor and the current sensor, and the total load value is corrected by updating the load value of the electronic load to meet the requirements of accuracy and dynamics. The specific process is: it should be detected whether the resistive load loading is completed. After the loading is completed, it should wait for 100ms or set this parameter according to the adjustment capability of the power supply. After the loading current enters a relatively stable period, the electronic load is adjusted. See the load closed-loop control flow chart Figure 5 , read the total load value and the resistive load acquisition value. The first step is to confirm whether the resistive load is loaded. Wait for 100ms and then read the current resistive load loading measurement value (sensor measurement value). When the current resistive load loading measurement value is greater than the total load value, reduce the resistive load loading value (the reduction is equal to the current resistive load loading measurement value plus 45% of the electronic load capacity minus the total load value) and re-enter the closed-loop process. If the total load value is greater than or equal to the resistive load loading measurement value, proceed to the next step. The total load value - resistive load loading measurement value should be less than the electronic load capacity. If it is greater than the electronic load capacity, increase the resistive load loading value (the increase is equal to the total load value - resistive load measurement value - 45% of the electronic load capacity) and re-enter the closed-loop process. If the total load value - resistive load measurement value is less than or equal to the electronic load capacity, enter the electronic load adjustment link. The total load value - resistive load loading measurement value is equal to the electronic load loading value. Load the electronic load.

[0050] In this embodiment, a control computer is used to perform load calculation, resistive load loading, electronic load loading, and load closed-loop control. The control computer can read the measured values ​​of the current and voltage measurement module. The measured load value of the resistive load is collected by the current and voltage acquisition module. After the control computer calculates the load compensation value, it is compensated by the electronic load to complete the closed-loop control. The requirements of capacity, accuracy, and dynamics are met.

[0051] The control computer includes a display and a computer. It has the ability to communicate with the current and voltage acquisition module, the electronic load, and the resistive load; it has the ability to distribute loads and drive electronic loads and resistive loads.

[0052] The control computer should have multiple load control modes and closed-loop dynamic adjustment control capabilities, and perform closed-loop calibration of the load value at a frequency of not less than 2 Hz to meet the dynamic requirements of the device.

[0053] The electronic load receives the loading command from the control computer and has control modes such as current, resistance, and power.

[0054] The resistive load receives the loading command from the control computer and controls the relay to switch the parallel relationship of the resistors. Each path corresponds to a resistor, and the current is increased or decreased by connecting or disconnecting the resistors.

[0055] The ratio of resistive load to electronic load is ≥4:1, or the electronic load capacity is configured according to the capacity of the dynamic load in actual working conditions; (resistive load capacity + 45% of electronic load capacity) ≮ load capacity requirement; by combining resistive load as the main and electronic load as the auxiliary, the capacity and economy requirements of the device can be met.

[0056] The resistive load takes 0.25A as the basic initial value under the nominal voltage and is divided into geometric multiples of 2 (0.25A, 1A, 2A, 4A, 8A...); the resistive load current and voltage acquisition module should adopt multi-sensor acquisition, reduce the acquisition error by comparing and screening the data source, and meet the high-precision requirements of the device.

[0057] The current and voltage acquisition module includes a voltage sensor, a current sensor, an analog-to-digital conversion component and a communication module, which sends the voltage and current information of the resistive load to the control computer.

[0058] The number of current and voltage acquisition modules is ≮3, and the acquisition range of the current and voltage sensor modules is 1 / 3, 2 / 3 and full scale of the rated load value of the resistive load box, or the measurement range is segmented according to the number of sensors and the distribution of actual measurement values. After obtaining the acquisition value, the sensor value with a range greater than the acquisition value and a smaller range should be used.

[0059] The control computer has load control capability and should have three control modes: constant resistance mode, constant current mode, and constant power mode. The control modes are as follows:

[0060] Constant resistance mode: The resistive load itself is in constant resistance mode, the electronic load is set to constant resistance mode, the calculated resistive load setting value + electronic load setting value = total setting value. Closed-loop load control can be turned off. If not, R = U / I is used for closed-loop control.

[0061] Constant current mode: The electronic load is set to constant current mode, and the closed-loop load control feedback signal is a resistive load current sensor.

[0062] Constant power mode: The electronic load is set to constant power mode, and the closed-loop load control feedback signal is calculated as P=U*I.

[0063] The protection scope of the present invention is not limited to the above-mentioned embodiments. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the scope of the present invention. If these changes and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include these changes and modifications.

Claims

1. A method for controlling load simulation of a power system, characterized in that: The steps include: s1. Get the required load value. If it is different from the last value, proceed to step s2. If it is the same as the last value, exit. s2. Load calculation, allocation to resistive load and electronic load: A% of the total capacity of the electronic load is used for allocation. When the loading value does not exceed A% of the total capacity of the electronic load, the electronic load is used directly; when the loading value exceeds A% of the electronic load capacity, the excess part is loaded with a resistive load, and finally the resistive load gear and the electronic load loading value are obtained; s3. Resistive load loading, electronic load loading: s3.1 For resistive load loading, when the calculated resistive load loading value is not equal to the current actual resistive load loading value, compare the difference between the calculated resistive load adding and unloading gears and the current actual resistive load adding and unloading gears, and add and unload the gears with differences to make the current actual resistive load gear consistent with the calculated resistive load gear; if the calculated resistive load loading value is equal to the current actual resistive load loading value, no action is taken and step 3.2 is entered; s3.2 If the calculated electronic load loading value is not equal to the current actual electronic load loading value, then the electronic load is loaded; if the calculated electronic load loading value is equal to the current actual electronic load loading value, then proceed to step s3.3; s3.3 Check the resistive load loading command. If the resistive load loading command has not been executed, re-execute it. If it has been executed, proceed to step 3.

4. s3.4 determines whether the electronic load loading is executed, if not executed, re-executes, if executed, the load loading is completed; s4. Load closed loop control: s4.1 reads the total load value; s4.2 Confirm whether the resistive load is loaded; s4.3 read the current resistive load measurement value. When the current resistive load measurement value is greater than the total load value, reduce the resistive load load value. The resistive load load value reduction is equal to the current resistive load measurement value plus the electronic load capacity A% minus the total load value, and then proceed to step s4.2; when the total load value is greater than or equal to the resistive load measurement value, proceed to step s4.4; s4.4 Determine whether the total load value - the current resistive load measurement value ≤ the electronic load capacity. If so, adjust the electronic load so that the total load value - the current resistive load measurement value is equal to the electronic load load value, and then load the electronic load; if not, increase the resistive load load value, and the increase in the resistive load load value is equal to the total load value minus the current resistive load measurement value minus the electronic load capacity A%, and then proceed to step s4.2; s5: Repeat the process from s1 to s4.

2. A power system load simulation loading control method as claimed in claim 1, characterized in that: When adding or unloading resistive loads, it is preferred to use a large gear.

3. A power system load simulation control method as claimed in claim 1, characterized in that: A% is 45%.

4. A power system load simulation control method as claimed in claim 1, characterized in that: In step s3, when a choice is needed between increasing and decreasing the load, priority is given to reducing the load, and when adding or unloading the electronic load and the resistive load, priority is given to adding or unloading the resistive load.

5. A power system load simulation control method as claimed in claim 1, characterized in that: The actual resistive load loading value is measured by a current and voltage measurement module, which uses current and voltage sensors.

6. A power system load simulation control method as claimed in claim 5, characterized in that: The load calculation, resistive load loading, electronic load loading and load closed-loop control are performed through the control computer. The control computer can read the measurement values ​​of the current and voltage measurement modules, and the electronic load can receive the loading command of the control computer; the resistive load can receive the loading command of the control computer and control the parallel relationship of the relay switching resistor.

7. A power system load simulation control method as claimed in claim 1, characterized in that: The ratio of resistive load to electronic load is ≥4:

1.

8. A power system load simulation control method as claimed in claim 1, characterized in that: The resistive load is based on an initial value of 0.25A at the nominal voltage and is divided into several gears in geometric multiples of 2.

9. A power system load simulation control method as claimed in claim 5, characterized in that: The number of current and voltage acquisition modules is ≮3, and the acquisition range of the current and voltage sensor modules is 1 / 3, 2 / 3 and full scale of the rated load value of the resistive load box.

10. A power system load simulation control method as claimed in claim 6, characterized in that: The resistive load is in constant resistance mode; the electronic load has constant resistance mode, constant current mode, and constant power mode; the control computer has constant resistance mode, constant current mode, and constant power mode control modes. In the constant resistance mode control mode, the electronic load is set to constant resistance mode, and the calculated resistive load loading value + calculated electronic load loading value = total setting value; in the constant current mode control mode, the electronic load is set to constant current mode, and the load closed-loop control feedback signal is the measurement value of the current sensor that measures the actual resistive load loading value; in the constant power mode control mode, the electronic load is set to constant power mode, and the load closed-loop control feedback signal is calculated as P = U*I.

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