阅读说明：本技术 一种同步信号缺失的判断方法 (Method for judging synchronization signal loss ) 是由 乐绪鑫 赵先元 王瑞清 刘钰琦 马小高 于 2020-04-17 设计创作，主要内容包括：本发明提供一种同步信号缺失的判断方法,包括以下具体步骤：通过定时执行的周期任务和外部同步信号触发的中断进程配合判断同步信号是否缺失：在外部输入的同步信号上升沿或下降沿触发的中断服务程序中清除同步断线故障标志及同步故障延时计数器,在定时执行的周期任务中递增同步故障延时计数器,一旦同步故障延时计数器达到阈值,则设置同步故障缺失标志。所述周期任务的执行周期与同步信号周期匹配,周期任务的执行周期设置为同步信号周期的一半。本发明通过同步信号触发中断进程和定时执行的周期任务相互配合检测出三相全控整流桥控制同步信号突然消失,增加同步信号消失保护,提高系统的可靠性。(The invention provides a method for judging synchronization signal loss, which comprises the following specific steps: whether the synchronous signal is lost is judged by matching the periodically executed task and an interrupt process triggered by an external synchronous signal: clearing the synchronous broken line fault mark and the synchronous fault delay counter in an interrupt service program triggered by the rising edge or the falling edge of an externally input synchronous signal, incrementing the synchronous fault delay counter in a periodic task executed at regular time, and setting the synchronous fault missing mark once the synchronous fault delay counter reaches a threshold value. The execution period of the periodic task is matched with the period of the synchronous signal, and the execution period of the periodic task is set to be half of the period of the synchronous signal. The invention detects the sudden disappearance of the synchronous signals controlled by the three-phase fully-controlled rectifier bridge through the mutual cooperation of the synchronous signal triggering interrupt process and the periodic tasks executed at regular time, increases the disappearance protection of the synchronous signals and improves the reliability of the system.)

1. A method for judging synchronization signal loss is characterized by comprising the following specific steps:

whether the synchronous signal is lost is judged by matching the periodically executed task and an interrupt process triggered by an external synchronous signal: clearing the synchronous broken line fault mark and the synchronous fault delay counter in an interrupt service program triggered by the rising edge or the falling edge of an externally input synchronous signal, incrementing the synchronous fault delay counter in a periodic task executed at regular time, and setting the synchronous fault missing mark once the synchronous fault delay counter reaches a threshold value.

2. The method according to claim 1, wherein the execution period of the periodic task matches the period of the synchronization signal, and the execution period of the periodic task is set to be half of the period of the synchronization signal.

Technical Field

The invention relates to the field of high-power electronics, in particular to a method for judging synchronization signal loss.

Background

Three-phase fully-controlled rectifier bridge as shown in figure 1May be expressed as U_out＝1.35Ucosα

Where α is the control angle of the rectifier bridge and U is the effective value of the input anode voltage.

The three-phase rectifier bridge control needs a synchronous signal to determine the starting time of each period, and the rising edge time of the trigger pulse is ensured to be matched with the control angle alpha.

After amplitude reduction and isolation of the input anode voltage synchronous transformer, the input anode voltage synchronous transformer is generally shaped into a square wave signal through a synchronous shaping circuit to serve as a synchronous signal accessed by a CPU. The phase relationship between the anode voltage, the synchronization signal and the trigger pulse is shown in fig. 2, with the abrupt change point (rising edge or falling edge) of the synchronization signal as the starting point of the period. The time difference of 2 adjacent mutation points of the synchronous signal is a period T, the time difference between the trigger pulse and the mutation point of the synchronous signal in the period is dT, and the controller ensures that the trigger pulse is matched with the control angle alpha by setting the delay dT of the trigger pulse. The rectifier bridge control angle can be expressed as

If the synchronous signal disappears due to a fault such as disconnection of the connection wire, the trigger pulse for controlling the rectifier bridge also disappears due to no relative starting point. In fact, three-phase synchronous signals are generally connected to the three-phase full-control rectifier bridge, one phase is selected by the controller to be used for driving the silicon controlled rectifier trigger pulse, and even if the currently used synchronous signals disappear due to faults, the controller can still select other normal signals, so that normal operation of equipment is guaranteed.

Disclosure of Invention

The invention aims to provide a method for judging the loss of synchronous signals, which increases the loss protection of the synchronous signals and improves the reliability of a system.

The technical scheme of the invention is as follows:

a method for judging synchronization signal loss comprises the following steps:

whether the synchronous signal is lost is judged by matching the periodically executed task and an interrupt process triggered by an external synchronous signal: clearing the synchronous broken line fault mark and the synchronous fault delay counter in an interrupt service program triggered by the rising edge or the falling edge of an externally input synchronous signal, incrementing the synchronous fault delay counter in a periodic task executed at regular time, and setting the synchronous fault missing mark once the synchronous fault delay counter reaches a threshold value.

The execution period of the periodic task is matched with the period of the synchronous signal, and the execution period of the periodic task is set to be half of the period of the synchronous signal.

Compared with the prior art, the invention has the beneficial effects that: when the synchronous signal is normal, the fault counter can not reach the threshold value all the time, once the synchronous signal disappears, the fault counter can be quickly increased to the threshold value, the synchronous signal disappearance alarm is triggered, the synchronous signal triggering interruption process and the periodic task executed at fixed time are matched with each other to detect that the synchronous signal suddenly disappears under the control of the three-phase full-control rectifier bridge, and the reliability of the system is improved.

Drawings

Fig. 1 is a schematic diagram of a three-phase fully controlled rectifier bridge.

Fig. 2 is a phase relationship of the intelligent rectifier bridge input voltage, the synchronization signal and the trigger pulse.

Fig. 3 is a schematic diagram of a periodic task executed in a timing manner and an interrupt process triggered by a synchronous signal to detect disappearance of the synchronous signal.

Fig. 4 is a schematic diagram of a sync signal disappearance detection flow in a periodic task executed at regular time.

FIG. 5 is a flow chart illustrating the detection of a synchronization signal fault in an interrupt service routine triggered by a synchronization signal.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the 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 derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 3 to fig. 5, a method for determining synchronization signal loss includes the following steps:

whether the synchronous signal is lost is judged by matching the periodically executed task and an interrupt process triggered by an external synchronous signal: clearing the synchronous broken line fault mark and the synchronous fault delay counter in an interrupt service program triggered by the rising edge or the falling edge of an externally input synchronous signal, incrementing the synchronous fault delay counter in a periodic task executed at regular time, and setting the synchronous fault missing mark once the synchronous fault delay counter reaches a threshold value.

The execution period of the periodic task is matched with the period of the synchronous signal, and the execution period of the periodic task is set to be half of the period of the synchronous signal.

The invention aims to improve the reliability of a system by increasing the synchronous signal disappearance protection.

The process related to the synchronization signal in the control program can be divided into two blocks: the synchronization signal triggers interrupts and timing the periodic tasks that are executed. The invention judges whether the synchronous signal disappears or not through the cooperation of the two processes, as shown in figure 3, a fault counter is increased in the periodic task process, and the fault counter is cleared in the interrupt process triggered by the synchronous signal. Therefore, when the synchronous signal is normal, the fault counter can not reach the threshold all the time, and once the synchronous signal disappears, the fault counter can be quickly increased to the threshold to trigger the alarm of the disappearance of the synchronous signal.

The execution period of the periodic tasks must match the synchronization signal period, typically set to 2 times the frequency of the synchronization signal. Taking a 50Hz power frequency signal as an example, the period of the synchronization signal is 20ms, and the execution period of the periodic task can be set to 10 ms.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.