CN102403734B - Method and device for embedded photovoltaic grid connected inversion based on multi-processor - Google Patents

Abstract

The present invention is applicable to the field of solar energy technology, and provides a method and device based on a multiprocessor embedded photovoltaic grid-connected inverter. The method includes the following steps: CPLD implements DSP control logic conversion, and the DSP processing chip collects photovoltaic grid-connected inverters in real time The electrical state of the inverter; judging whether the grid-connection condition is met according to the electrical state; if the system is in the running state, then load the corresponding grid-connection control step, and the grid-connection control step is performed between the DSP processing chip and the ARM through the serial port Real-time data communication and command interaction, as well as DSP execution of photovoltaic grid-connected inverter operation state switching detection and corresponding function processing logic. Compared with the existing inverter processor structure, this processing mechanism has greatly improved system functionality, real-time performance, scalability and system upgradeability.

Description

A method and device based on multi-processor embedded photovoltaic grid-connected inverter

technical field

The invention belongs to the technical field of solar energy, and in particular relates to a method and device based on a multiprocessor embedded photovoltaic grid-connected inverter.

Background technique

With the increasingly powerful functions of photovoltaic power plants, the demand for data storage, data transmission speed and data transmission methods is becoming more and more urgent, and the requirements for the functionality and real-time performance of the processors used in photovoltaic grid-connected inverters are getting higher and higher. .

At present, a single DSP processor or other single-chip microcomputers are used in photovoltaic grid-connected inverters. Due to the use of a single processor, its hardware resources are limited, and it cannot meet the real-time touch display based on the multi-interface style of the operating system, nor can it meet the functional requirements of remote data communication between the network and GPRS and real-time response to communication commands. Therefore, the existing photovoltaic grid-connected inverter adopts a single processor or other single-chip microcomputer, which has the problems of relatively single function, poor real-time performance, poor scalability, and difficult upgrades.

Contents of the invention

In order to solve the above technical problems, the purpose of the embodiments of the present invention is to provide a multi-processor embedded photovoltaic grid-connected inverter method, which improves the functionality, real-time performance and scalability of the photovoltaic grid-connected system.

The embodiment of the present invention is achieved in this way, a method based on multi-processor embedded photovoltaic grid-connected inverter, the method includes the following steps:

The DSP processing chip collects the electrical status of the photovoltaic grid-connected inverter in real time;

Judging whether the grid connection condition is met according to the electrical state;

If the system is in the running state, then load the corresponding grid-connected control steps, the grid-connected control steps are DSP to perform photovoltaic grid-connected inverter running state switching detection and enter the running state processing flow and DSP processing chip and ARM through the serial port Real-time data communication and command interaction, among which, the real-time data communication and command interaction between the DSP processing chip and the ARM through the serial port specifically include: saving the running status information of the photovoltaic grid-connected inverter and displaying it in real time on the touch screen, ARM interrupting the response to the touch screen command and Interact with the DSP processing chip for commands.

Further, the method also includes:

When the inverter system is running, close the AC side and DC side circuit breakers;

The system enters the starting state, and performs system self-test and initialization;

Detect whether the grid-connected operation conditions are met;

If the grid-connected conditions are met, it enters the operation state processing flow, and detects the inverter operation state in the DSP, the touch screen output command or whether someone artificially cuts off the circuit breaker in real time, performs corresponding state switching, and enters the corresponding processing flow.

Further, the process of entering the running state includes:

Detect and record the working status of the inverter in the DSP;

If it is in the running state, if it is the first run after starting up, update various parameter settings in the DSP, the DSP processor starts the acquisition, protection and grid-connected control algorithm, creates sub-thread 1 to realize the communication between ARM and DSP, and displays the operation of the inverter in real time Information and command interaction, and create a sub-thread 2 to realize the communication function with the remote monitoring terminal through the network port/RS485/GPRS, and respond to the interrupt command and parameter modification settings of the touch screen at the same time;

If it is in a fault state, start the protection program, cut off the AC contactor, save the fault information, give a fault alarm indication, continuously detect whether the system fault is cleared and whether there is a power-on command, and switch the state according to the detection result;

If it is in the standby state, check whether the inverter system meets the grid-connection conditions in a loop, and switch the state if it meets the requirements;

If it is in the shutdown state, disconnect the AC contactor, and check whether the system meets the start-up conditions in a loop, and enter the start-up state if it is satisfied.

Another embodiment of the present invention is to provide a multiprocessor-based embedded photovoltaic grid-connected inverter device, the device includes a signal isolation and processing board with a built-in DSP processing chip, and a data monitoring and communication board with a built-in ARM chip with the display board,

The DSP processing chip collects the electrical state of the photovoltaic grid-connected inverter in real time, and judges whether the grid-connected condition is met according to the electrical state; if the system is in the running state, loads the corresponding grid-connected control step, and the grid-connected control step is DSP The processing chip performs the switching detection of the running state of the photovoltaic grid-connected inverter and the processing flow of entering the running state, as well as the real-time data communication and command interaction between the DSP processing chip and the ARM chip through the serial port.

Among them, the real-time data communication and command interaction between the DSP processing chip and the ARM chip through the serial port specifically includes: the operation status information storage of the photovoltaic grid-connected inverter and the real-time display on the touch screen, the ARM chip interrupts the response to the touch screen command and executes the command with the DSP processing chip interact.

In the embodiment of the present invention, a multi-processor synchronous operation and coordinated processing operation mechanism is established to take into account the real-time performance of each processor and improve the processing capacity of the entire inverter system. Compared with the existing inverter processor structure, this processing mechanism has greatly improved system functionality, real-time performance, scalability and system upgradeability.

Description of drawings

Fig. 1 is a basic structural diagram of a photovoltaic grid-connected inverter provided by an embodiment of the present invention;

Fig. 2 is a flowchart of a multiprocessor-based embedded photovoltaic grid-connected inverter implementation method provided by an embodiment of the present invention;

Fig. 3 is a flow chart of the processing of the multiprocessor in different working states of the inverter provided by the embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Fig. 1 shows the basic structure of a photovoltaic grid-connected inverter provided by an embodiment of the present invention. Voltage and current sensors are installed on the DC input terminal, AC output terminal and grid side of the photovoltaic grid-connected inverter. The photovoltaic grid-connected inverter includes: DC circuit breaker, capacitor array, three-phase full-bridge inverter, filter, three-phase transformer, AC contactor, AC circuit breaker, DC side signal sampling, inverter output signal sampling , Network side signal sampling, signal isolation and processing board, data monitoring communication display board and touch screen.

A DSP processing chip and a CPLD logic chip are integrated on the signal isolation and processing board.

The electrical state of the photovoltaic grid-connected inverter is collected in real time through the DSP processing chip, and it is judged whether the grid-connected conditions are met. If the system is in the running state, the corresponding grid-connected control algorithm is loaded. The DSP processing chip control logic conversion is realized through the CPLD chip, and the DSP realizes the switching detection of the inverter running state and the processing flow of entering the running state. The real-time data communication and command interaction are performed between the DSP processing chip and the ARM through the serial port. Among them, including the storage of the running state information of the photovoltaic grid-connected inverter and the real-time display of the touch screen, the ARM interrupt responds to the touch screen command and interacts with the DSP processing chip.

Figure 2 shows the flow of the implementation method based on multi-processor embedded photovoltaic grid-connected inverter, which is described in detail as follows:

In step S101, when the inverter system is running, the circuit breakers on the AC side and the DC side are first closed.

In step S102, the system enters the starting state, and performs system self-check and initialization.

In step S103, it is detected whether the grid-connected operation condition is satisfied. If it is satisfied, execute step S104, otherwise repeatedly execute step S103, that is, repeatedly perform detection.

In step S104, grid-connected operation is performed, and system status is detected.

When the grid-connected operation condition is met, enter the operation state processing flow. The detection system state is specifically: the DSP processing chip detects the running state of the photovoltaic grid-connected inverter in real time, the output command of the touch screen or the on-off state of the circuit breaker.

In step S105, it is determined whether state switching is required. Execute step S106 if necessary, otherwise end the process.

In step S106, a corresponding state switch is performed according to a corresponding instruction, and a corresponding processing flow is entered.

FIG. 3 shows the processing flow of the multiprocessor provided by the embodiment of the present invention under different working states of the inverter, and the details are as follows:

The ARM processor sets the main thread and two sub-threads.

In step S301, the working state of the photovoltaic grid-connected inverter recorded in the DSP processor is detected. The working state of photovoltaic grid-connected inverter is divided into running state, fault state, standby state and shutdown state. When it is in running state, execute step S3011; when it is in failure state, execute step S3021; when it is in standby state, execute step S3031; when it is in shutdown state, execute step S3041.

In step S3011, when it is running for the first time after starting up, update various parameter settings in the DSP processing chip.

In step S3012, the DSP processing chip starts the collection, protection and grid connection control algorithms.

In step S3013, sub-thread 1 is created to realize the communication between ARM and DSP, to display inverter operation information and command interaction in real time.

In step S3014, a sub-thread 2 is created to realize the communication function with the remote monitoring terminal through the network port/RS485/GPRS.

In step S3015, the settings are modified in response to the interruption command and parameters of the touch screen.

In step S3016, it is detected whether there is a change in the state of the DSP or an output command from the touch screen or the circuit breaker is manually cut off, and it is judged whether the running state of the inverter is switched. In step S3021, if it is a fault state, start a protection program to cut off the AC contactor.

In step S3022, save the fault information.

In step S3023, a failure alarm indication is performed.

In step S3024, it is continuously checked whether the system fault is cleared. According to the detection result, the state switching is performed.

In step S3025, continuously detect whether there is a power-on command. According to the detection result, the state switching is performed.

In step S3031, if it is in the standby state, check whether the inverter system satisfies the grid-connection condition in a loop. If satisfied, skip to step S302.

In step S3041, if it is in shutdown state, disconnect the AC contactor.

In step S3042, it is checked whether the system meets the start-up condition in a loop.

In step S3043, if it is satisfied, enter the starting state.

In step S302, state switching is performed.

In the embodiment of the present invention, a multi-processor synchronous operation and coordinated processing operation mechanism is established to take into account the real-time performance of each processor and improve the processing capacity of the entire inverter system. Compared with the existing inverter processor structure, this processing mechanism has greatly improved performance in terms of system functionality, real-time performance, scalability and system upgradeability.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (4)

1. the method based on multiprocessor embedded photovoltaic grid connected inversion, is characterized in that, said method comprising the steps of:

DSP process chip Real-time Collection photovoltaic combining inverter electric state;

According to described electric state, judge whether to meet grid-connected condition;

If system is in running status, load corresponding grid-connected control step, described grid-connected control step be DSP process chip carry out photovoltaic combining inverter running status change detection and enter running status handling process and DSP process chip and ARM chip between by serial ports, carry out real-time data communication and command interaction

Wherein, between DSP process chip and ARM chip, by serial ports, carry out real-time data communication and command interaction specifically comprises: photovoltaic combining inverter running state information is preserved with touch-screen and shown in real time, ARM chip interrupt response touch-screen order is also carried out command interaction with DSP process chip.

2. the method based on multiprocessor embedded photovoltaic grid connected inversion according to claim 1, is characterized in that, described method also comprises:

During inversion system operation, closed AC and DC side circuit breaker;

System enters state in startup, carries out System self-test and initialization;

Detect and whether meet the condition that is incorporated into the power networks;

If meet grid-connected condition, enter running status handling process, and detect in real time invertor operation state in DSP, touch-screen output command or whether have artificial cut-out circuit breaker phenomenon, carry out corresponding state switching, and enter corresponding handling process.

3. the method based on multiprocessor embedded photovoltaic grid connected inversion according to claim 2, is characterized in that, described in enter running status handling process and comprise:

Detect in DSP and record inverter operating state;

If in running status, if start is operation first, upgrade various parameter settings in DSP, dsp processor starts collection, protection and grid-connected control algolithm, create sub-thread 1 and realize ARM and DSP communication, show in real time invertor operation information and command interaction, and, create sub-thread 2 and realize by network interface/RS485/GPRS and remote monitoring end communication function, respond interruptive command and the parameter modification setting of touch-screen simultaneously;

If malfunction, starting protection program, cuts off A.C. contactor, preserves fault message, carries out fault alarm indication, and constantly whether detection system fault is removed and whether have power-on command, according to testing result, carries out state switching;

If holding state, whether cycle detection inversion system meets grid-connected condition, if meet, carries out state switching;

If stopped status, disconnects A.C. contactor, whether cycle detection system meets entry condition, if meet the state in startup that enters.

4. one kind based on multiprocessor embedded photovoltaic grid connected inversion device, it is characterized in that, described device comprises signal isolation and the disposable plates that is built-in with DSP process chip, and, be built-in with data monitoring, communication and the display panel of ARM chip, DSP process chip Real-time Collection photovoltaic combining inverter electric state, and judge whether to meet grid-connected condition according to described electric state, if system is in running status, load corresponding grid-connected control step, described grid-connected control step be DSP process chip carry out photovoltaic combining inverter running status change detection and enter running status handling process and DSP process chip and ARM chip between by serial ports, carry out real-time data communication and command interaction, wherein, between DSP process chip and ARM chip, by serial ports, carry out real-time data communication and command interaction specifically comprises: photovoltaic combining inverter running state information is preserved with touch-screen and shown in real time, the response touch-screen order of ARM chip interrupt is also carried out command interaction with DSP process chip.

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