Inverter control method

Abstract

Disclosed in the present invention is an inverter control method. By means of accurate voltage and current measurement, real-time power calculation, dynamic output adjustment, feedback monitoring and protection mechanisms, efficient and stable control over an inverter is realized, so as to adapt to rapid changes in a power grid and improve the regulation capability of a power system; and by means of finely controlling the current and voltage of the inverter, a rapid response to changes in the power grid is realized, thereby improving the operating efficiency of the inverter and the stability of the power grid. The method is particularly applicable to a distributed power resource with a limited energy storage capacity, and can meet the urgent need of the power system for a rapid regulation capability.

Description

An inverter control method Technical Field

[0001] This invention relates to the field of power electronics technology, specifically to an inverter control method. Background Technology

[0002] With the widespread application of renewable energy, inverters are playing an increasingly important role in power systems. Inverters not only facilitate the reverse flow of energy but also provide rapid support when electricity is needed.

[0003] However, existing inverter control methods suffer from problems such as slow response speed and poor stability, especially when grid conditions change, making it difficult to achieve fast and accurate control. Summary of the Invention

[0004] The purpose of this invention is to provide an inverter control method that achieves precise control of the inverter's current and voltage through voltage and current inner loop control, power synchronization and compensation, thereby improving the inverter's operating efficiency and enhancing its responsiveness in the power grid.

[0005] The objective of this invention can be achieved through the following technical solution: an inverter control method, which achieves efficient and stable control of the inverter through precise voltage and current measurement, real-time power calculation, dynamic output adjustment, feedback monitoring, and protection mechanisms, so as to adapt to rapid changes in the power grid and improve the regulation capability of the power system. The method specifically includes the following steps:

[0006] Step 1: Achieve precise control of the inverter's current and voltage through accurate voltage and current measurement and coordinate transformation;

[0007] Step 2: Calculate instantaneous power in real time and synchronize with grid power to enable the inverter to quickly adapt to grid changes and achieve immediate response;

[0008] Step 3: Employ a real-time compensation mechanism to dynamically adjust the inverter output to meet the power system's urgent need for rapid regulation capabilities;

[0009] Step 4: Add a feedback loop to monitor the inverter's output and adjust it according to the actual needs of the power grid;

[0010] Step 5: Add a protection mechanism to automatically disconnect the inverter from the grid when a grid anomaly is detected.

[0011] Preferably, in step one, the voltage and current values ​​are detected by ADC or SDFM to provide real-time data support for the control algorithm.

[0012] Preferably, the coordinate transformation in step one includes Clark transformation and Park transformation.

[0013] Preferably, power synchronization in step two is achieved by calculating the power factor and phase angle of the power grid, wherein the phase angle is detected by phase-locked loop technology.

[0014] Preferably, the real-time compensation mechanism in step three includes adjusting the amplitude and phase of the inverter output current.

[0015] Preferably, the feedback mechanism in step four includes voltage feedback and current feedback.

[0016] Preferably, the voltage feedback involves real-time monitoring of the output voltage via a voltage sensor and comparison with the desired voltage. The controller, after comparing the received voltage signal with the desired voltage, generates an error signal based on the comparison result. This error signal is used to adjust the switching state of the power switching devices to ensure the output voltage matches the desired voltage. The output AC power supply voltage is first reduced to a lower level and then fed to the control IC's shutdown pin. The control IC uses a fixed voltage from the inverter battery to monitor this feedback signal. If the output voltage exceeds a predetermined value, the error amplifier is activated, thereby shutting down the inverter's output PWM and reducing the output voltage to a safe level.

[0017] Preferably, the current feedback monitors the output current in real time through a current sensor and feeds the monitored current signal back to the controller. The controller compares the received current signal with the desired current and adjusts the switching state of the switching device according to the comparison result, so that the output current is consistent with the desired current. A dual-loop control scheme with load current feedforward inductor current inner loop and output voltage outer loop is adopted, wherein the outer loop is the instantaneous value feedback of output voltage and the inner loop is the instantaneous value feedback of inductor current.

[0018] Preferably, the control method further includes a prediction component for predicting the future state of the power grid and responding in advance.

[0019] Preferably, the control method also includes a communication link for information exchange and coordinated control between inverters.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (1) This control method can achieve efficient and stable control of the inverter through precise voltage and current measurement, real-time power calculation, dynamic output adjustment, feedback monitoring and protection mechanism. In particular, in step one, the voltage and current values ​​are detected by ADC or SDFM to provide real-time data support for the control algorithm. This helps to improve the inverter's response speed and control accuracy to grid changes. At the same time, in step two, the instantaneous power is calculated in real time and the grid power is synchronized, so that the inverter can quickly adapt to the grid changes and achieve immediate response. This rapid response capability is crucial for maintaining the stable operation of the grid. In particular, when the grid fluctuates or the load changes, the output can be quickly adjusted to reduce the impact on the grid and improve the stability and reliability of the entire power system.

[0022] (2) The control method adopts a real-time compensation mechanism to dynamically adjust the output of the inverter in order to meet the urgent need of the power system for rapid adjustment capability. This dynamic adjustment capability enables the inverter to better adapt to the load changes of the power grid, optimize the adjustment capability of the power system, and thus improve the flexibility and economy of the power system.

[0023] (3) The control method incorporates a feedback loop to monitor the inverter output and adjust it according to the actual needs of the power grid. This not only improves the system's response speed but also enhances the system's safety and reliability. The addition of a protection loop allows the inverter to be automatically disconnected from the power grid when an abnormality is detected. This effectively prevents power grid faults from damaging the inverter or other parts of the power grid. Furthermore, the preferred current feedback uses a current sensor to monitor the output current in real time and feeds the monitored current signal back to the controller. The controller compares the received current signal with the desired current and adjusts the switching state of the switching devices based on the comparison result, thereby keeping the output current consistent with the desired current. This closed-loop control strategy further enhances the system's safety and reliability. Attached Figure Description

[0024] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0025] Figure 1 is a flowchart of the overall implementation of the present invention. Detailed Implementation

[0026] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please refer to Figure 1. An inverter control method achieves efficient and stable control of the inverter through precise voltage and current measurement, real-time power calculation, dynamic output adjustment, feedback monitoring, and protection mechanisms. This adapts to rapid changes in the power grid and improves the regulation capability of the power system. The method specifically includes the following steps:

[0028] Step 1: Achieve precise control of the inverter's current and voltage through accurate voltage and current measurement and coordinate transformation;

[0029] Step 2: Calculate instantaneous power in real time and synchronize with grid power to enable the inverter to quickly adapt to grid changes and achieve immediate response;

[0030] Step 3: Employ a real-time compensation mechanism to dynamically adjust the inverter output to meet the power system's urgent need for rapid regulation capabilities;

[0031] Step 4: Add a feedback loop to monitor the inverter's output and adjust it according to the actual needs of the power grid;

[0032] Step 5: Add a protection mechanism to automatically disconnect the inverter from the grid when a grid anomaly is detected. Example 1

[0033] Taking residential solar power systems as an example, inverters convert direct current (DC) generated by solar panels into alternating current (AC) for home use or for grid connection. Specific methods include:

[0034] Step 1: Use a high-precision analog-to-digital converter (ADC) to detect the voltage and current values ​​output by the solar panel in real time, and apply Clark and Park transformations to convert the three-phase current and voltage signals into two-phase quadrature signals for more precise control of the inverter;

[0035] Step 2: Calculate the instantaneous power of the solar inverter in real time and synchronize it with the power of the grid. Power synchronization is achieved by calculating the power factor and phase angle of the grid, where the phase angle is detected by phase-locked loop technology.

[0036] Step 3: Adopt a real-time compensation mechanism to adjust the amplitude and phase of the inverter output current according to the grid demand, such as increasing the output when the grid load is at its peak and decreasing the output when the grid load is at its low peak.

[0037] Step 4: Add voltage and current feedback loops, monitor the output voltage and current through sensors, compare them with the expected values, and adjust the switching state of the inverter to maintain consistency;

[0038] Step 5: Add a protection mechanism. Once a grid anomaly is detected, such as a voltage surge or frequency deviation, the inverter will be automatically disconnected from the grid to protect the system safety.

[0039] Step Six: Predict the output of the solar panels using historical data and weather forecasts, and adjust the inverter settings in advance;

[0040] Step 7: Enable information exchange and coordinated control among multiple inverters within the home to optimize energy management. Example 2

[0041] In the context of industrial energy storage systems, inverters are used to manage the charging and discharging of battery energy storage systems to provide a stable power supply. Specific methods include:

[0042] Step 1: Use a high-speed data acquisition system (SDFM) to detect the voltage and current values ​​between the battery energy storage system and the grid, and apply coordinate transformation techniques, such as Clark transformation and Park transformation, to achieve precise control of the inverter;

[0043] Step 2: Calculate the instantaneous power of the energy storage inverter in real time and synchronize it with the power of the grid. Use phase-locked loop technology to detect the phase angle of the grid to achieve precise power synchronization.

[0044] Step 3: Adopt a real-time compensation mechanism to adjust the amplitude and phase of the inverter output current according to the grid demand, such as increasing the output when the grid load is at its peak and decreasing the output when the grid load is at its low peak.

[0045] Step 4: Add voltage and current feedback loops, monitor the output voltage and current through sensors, compare them with the expected values, and adjust the switching state of the inverter to maintain consistency;

[0046] Step 5: Add a protection mechanism. Once a grid anomaly is detected, such as a voltage surge or frequency deviation, the inverter will be automatically disconnected from the grid to protect the system safety.

[0047] Step Six: Utilize grid load forecasting and battery status forecasting to adjust the inverter's charging and discharging strategy in advance;

[0048] Step 7: Enable information exchange and coordinated control among multiple energy storage inverters within the industrial park to improve energy utilization efficiency.

[0049] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An inverter control method, characterized in that, By employing precise voltage and current measurement, real-time power calculation, dynamic output adjustment, feedback monitoring, and protection mechanisms, efficient and stable control of the inverter is achieved to adapt to rapid changes in the power grid and improve the power system's regulation capabilities. This method specifically includes the following steps: Step 1: Achieve precise control of the inverter's current and voltage through accurate voltage and current measurement and coordinate transformation; Step 2: Calculate instantaneous power in real time and synchronize with grid power to enable the inverter to quickly adapt to grid changes and achieve immediate response; Step 3: Employ a real-time compensation mechanism to dynamically adjust the inverter output to meet the power system's urgent need for rapid regulation capabilities; Step 4: Add a feedback loop to monitor the inverter's output and adjust it according to the actual needs of the power grid; Step 5: Add a protection mechanism to automatically disconnect the inverter from the grid when a grid anomaly is detected.

2. The inverter control method according to claim 1, characterized in that, Step 1 involves detecting voltage and current values ​​using an ADC or SDFM to provide real-time data support for the control algorithm.

3. The inverter control method according to claim 1, characterized in that, The coordinate transformation in step one includes Clark transformation and Park transformation.

4. The inverter control method according to claim 1, characterized in that, The power synchronization in step two is achieved by calculating the power factor and phase angle of the power grid, where the phase angle is detected by phase-locked loop technology.

5. The inverter control method according to claim 1, characterized in that, The real-time compensation mechanism in step three includes adjusting the amplitude and phase of the inverter output current.

6. The inverter control method according to claim 1, characterized in that, The feedback mechanism in step four includes voltage feedback and current feedback.

7. The inverter control method according to claim 6, characterized in that, Voltage feedback monitors the output voltage in real time via a voltage sensor and compares it with the desired voltage. The controller, after comparing the received voltage signal with the desired voltage, generates an error signal based on the comparison result. This error signal is used to adjust the switching state of the power switching devices to ensure the output voltage matches the desired voltage. The output AC power supply voltage is first reduced to a lower level and then fed to the control IC's shutdown pin. The control IC uses a fixed voltage from the inverter battery to monitor this feedback signal. If the output voltage exceeds a predetermined value, the error amplifier activates, thereby shutting down the inverter's output PWM and reducing the output voltage to a safe level.

8. The inverter control method according to claim 6, characterized in that, The current feedback monitors the output current in real time through a current sensor and feeds the monitored current signal back to the controller. The controller compares the received current signal with the desired current and adjusts the switching state of the switching device according to the comparison result, so that the output current is consistent with the desired current. A dual-loop control scheme with load current feedforward inductor current inner loop and output voltage outer loop is adopted, where the outer loop is the instantaneous value feedback of output voltage and the inner loop is the instantaneous value feedback of inductor current.

9. The inverter control method according to claim 1, characterized in that, The control method also includes a prediction component to forecast the future state of the power grid and respond in advance.

10. The inverter control method according to claim 1, characterized in that, The control method also includes a communication link to enable information exchange and coordinated control between inverters.

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