CN1761115B - Intelligent Identification Method of Power System Fault - Google Patents

Abstract

The present invention relates to an intelligent identification method for a power supply system fault. In order to solve the problem of being unable to accurately identify which power supply module is faulty in the prior art, in the present invention, each power supply module uses its own address signal in the power supply system Determine the sequence of self-inspection, and then determine the start time of self-inspection after detecting abnormal output voltage according to the sequence of self-inspection and the preset inspection cycle; when detecting abnormal output voltage of the power system, for each When the power module reaches its own inspection time, it first stops outputting voltage to the power system, and then detects the current output voltage of the power system. If the current output voltage is normal, it is considered to be a failure; if it is not normal, it is considered to be normal. At this time, the locking process can be performed through its own control circuit, so that the power module is separated from the entire power system. In addition, it is also possible to find out the faulty power supply module by making all the power supply modules stop output voltage first, and then restore the output voltage in sequence.

Description

Intelligent Identification Method of Power System Fault

technical field

The invention relates to a power supply system composed of multiple power supply modules, and more specifically, to an intelligent identification method for such a power supply system failure.

Background technique

Figure 1 is a schematic diagram of a power supply system, in which the power supply system is composed of multiple power modules, and each power module realizes output hot-swapping through a controllable disconnection device (relays, MOS tubes, etc. are common) function, the output of each power module is connected in parallel through the DC bus on the right to supply power to the load.

For this kind of power supply system, when one of the power supply modules has an internal short circuit due to damage, no matter whether the short circuit occurs in front of or behind the relay, since the power supply modules are connected in parallel with each other, for all power supply modules, Its output will be in a short-circuit state. At this time, it will not be possible to tell which power module is faulty, but it will be regarded as a short-circuit fault in the entire power system. As a result, the entire power system will stop working. Similarly, if one of the power modules has an output overvoltage fault, since the outputs of all power modules are connected in parallel to the DC bus of the system, all power modules will detect that the output voltage exceeds the standard, and the existing output overvoltage protection This method will lock all the power modules, and as a result, the entire power system will stop working.

Contents of the invention

In view of the above defects of the prior art, the present invention solves the problem that the existing power system fault protection method cannot accurately identify which power module is faulty, which will cause the entire power system to stop working, so as to achieve a more accurate and reliable power supply Intelligent identification of system faults.

The technical solution adopted by the present invention to solve the technical problem is to provide an intelligent identification method for power system faults, the power system includes a plurality of power modules connected in parallel, and each power module The address signal determines the sequence of self-inspection, and then according to the sequence of self-inspection and the preset inspection period, determines the start time of self-inspection after detecting abnormal output voltage;

When the output voltage of the power system is detected to be abnormal, handle each power module according to the following steps:

Step 1. Stop outputting voltage to the power supply system when the self-inspection time is reached;

Step 2, detecting the current output voltage of the power system;

Step 3, judging whether the current output voltage of the power supply system is normal, if it is normal, it is determined that it has a fault; if it is not normal, it is determined that it is normal.

In step 1 of the above method, the power supply module stops outputting voltage to the power supply system by closing its internal power conversion circuit and/or disconnecting the controllable disconnection device at its output end; the controllable disconnection The device is a relay or a controllable switch tube.

In step S13 of the above method, in step 3, if the power supply module determines that it has failed, it will perform locking processing through its own control circuit and report the failure situation at the same time.

In step 3 of the above method, if the current output voltage of the power supply system is abnormal, the power supply module does not determine that it has failed itself. At this time, the power supply module preferably waits for all the power supply modules to complete their own inspection. After the inspection, resume normal operation and output voltage to the power system again.

In the above-mentioned method of the present invention, the power module that is determined not to have failed continues to detect the output voltage of the power system, if the output voltage of the power system is still abnormal when the last power module is inspected, then It is determined that a fault other than the power system has occurred and the fault is reported. It may also not be determined directly, but output voltage to the power system again after the inspection of the last power module, and then perform steps 1 to 3. After repeating this at least once, if the output voltage of the power system is still abnormal, It was determined that there was a failure outside the power supply system and reported the failure.

In another solution of the present invention, when the output voltage of the power system is detected to be abnormal, each power module is processed according to the following steps:

The first step is to first stop outputting voltage to the power system, and resume normal operation when the self-inspection time is reached, and output voltage to the power system again;

The second step is to detect the current output voltage of the power supply system;

The third step is to judge whether the current output voltage of the power system is normal. If it is not normal, it is determined that it has broken down, and the output voltage to the power system is stopped again. If it is normal, it is determined that it has not failed and keeps working normally. .

In the third step of this solution, if the power module determines that it has failed, it will also perform locking processing through its own control circuit and report the failure situation at the same time.

In the third step of this solution, the power module that has identified itself as faulty continues to detect the output voltage of the power system, if the output voltage of the power system is still abnormal when the last power module is inspected , it is determined that a fault outside the power system has occurred and the fault is reported. It may also not be determined directly, but output voltage to the power system again after the inspection of the last power module, and then perform the first to third steps. After repeating this at least once, if the output voltage of the power system is still If it is not normal, it is determined that there is a fault outside the power supply system and the fault is reported.

In the third step of this solution, if the current output voltage of the power system is normal, the power module determines that it is not a failure of itself, stops outputting voltage to the power system again, and waits; similarly, at this time It is better to wait for all the power supply modules to complete their self-inspection before returning to normal operation and outputting voltage to the power supply system again.

It can be known from the above scheme that in the method of the present invention, each power module determines its own inspection sequence and inspection start time after a failure occurs based on its address information, and simply stops (recovers) the output voltage operation, and then cooperates with the corresponding The output voltage detection can accurately find out the one or more power modules that have actually failed, so that the faulty power module can be separated from the entire power system, so that the power system can automatically resume normal operation.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Figure 1 is a schematic diagram of a power system composed of multiple power modules connected in parallel;

Fig. 2 is a flowchart of fault identification in a preferred embodiment of the present invention;

Fig. 3 is a flowchart of fault identification in another preferred embodiment of the present invention.

Detailed ways

In a preferred implementation of the present invention, the fault intelligent identification control is performed according to the process shown in FIG. 2 . For the power system shown in Figure 1 which is composed of multiple power modules connected in parallel, through the process shown in Figure 2, it is possible to accurately and effectively find out which power module actually failed.

In this embodiment, the control circuit of each power supply module must be improved accordingly. If the comprehensive control circuit of various faults is realized in the form of software, it is not necessary to make any improvement to the control circuit, only the software needs to be changed. , the purpose of the improvement is to enable the power module to determine its own inspection sequence according to its own address signal in the power system, and then determine when an abnormal output voltage is detected according to its own inspection sequence and preset inspection cycle. The startup time of self-inspection after starting. Assume that there are 8 power modules in the power system, and the addresses are 000, 001, 010, ..., 110, 111, then the inspection sequence is the first with the address of 000, the second with the address of 001, and so on. The one with 111 is the last; of course, any one in the middle is also acceptable, for example, 011 is the first, then 100 is the second at this time, and so on, 111 is the fifth, and 010 is the eighth. For ease of understanding and implementation, the former method is used to arrange the inspection sequence in this embodiment. The inspection cycle in this article refers to the time required for each power module to complete its own inspection, including the actual time required to execute each step, and the delay time set according to specific needs. Assuming that the inspection period is 1 second, taking the above-mentioned 8 power modules as an example, for the power module with address 000, its start-up time is 0 seconds, that is, the inspection is performed immediately after the abnormal output voltage is detected, and at 0 The self-inspection is completed within the time period of -1 second; for the power module with address 100, its start-up time is 4 seconds, that is, the inspection is performed in the 4th second after the abnormal output voltage is detected, and in the 4th The self-inspection is completed within the time period of -5 seconds.

During specific implementation, an appropriate inspection cycle can be determined according to the actual time required to execute each step during the inspection and the delay time set according to specific needs. It can be seen from the previous description that after any power module is connected to the power system, it can automatically obtain an address according to its plugged position, and determine its own inspection sequence and startup time according to the address.

The determination of whether the power module exits the inspection state can be set on-site with hardware circuits such as dial switches, or can be set in the form of software according to specific applications. It can also be completed by establishing communication between power modules, such as specifying any power supply. After the module completes its own inspection, it immediately sends a self-inspection completion signal to other power modules. If it does not receive the self-inspection completion signal from other power modules within the preset inspection period, all power modules will default to the power system. The inspection is complete.

Figure 2 shows the inspection process of a single power module. When an abnormal output voltage of the power system is detected (possibly due to output short circuit or output overvoltage), each power module executes this process independently, so this process The premise is that an abnormal output voltage has been detected.

It can be seen from Figure 2 that for each power module, first check whether the self-inspection time has arrived, if not, continue to wait, and if it does, stop outputting voltage to the power system. Its internal power conversion circuit, or disconnect its output controllable disengagement device (relay in Figure 1, it can also be a controllable switch, such as a MOS tube) to stop the output voltage to the power system, or it can be turned off The controllable disengagement device is disconnected simultaneously with the power conversion circuit.

Then, the control circuit of the power module detects the current output voltage of the power system, and then judges whether the current output voltage is normal. Lock-up processing is carried out through its own control circuit to completely break away from the entire power supply system; since only this power module stops outputting voltage at this time, other power modules continue to output voltage, so if the current output voltage of the entire power supply system is normal, then It can be determined that the other power modules have no faults. Accordingly, the power module can also send a signal to other power modules that the fault has been eliminated and stop this inspection (this step is not shown in the figure); You can skip this step and let each power module complete its own inspection process independently, because after the faulty power module is separated from the system, the output voltage of the power system can return to normal, and the power system detected by the normal power module at this time The output voltage of the power supply system is normal, so it can automatically exit the inspection state. Generally, the detection of the output voltage of the power supply system by the power module is real-time; The detection of the output voltage of the system is collected at a certain time interval, and the fixed time interval is much shorter than the inspection time.

If the current output voltage of the power system is not normal, the power module does not believe that it has failed itself. At this time, the power module will wait for all power modules to complete their own inspections before returning to normal work and re-introducing the power supply system. The output voltage. Considering that usually only one power module fails, and the probability of two or more power modules being damaged at the same time is very low, when the power module is determined not to have failed itself, it can resume normal operation immediately. However, the preferred way is to wait for all the power modules to complete their self-inspection before returning to normal work.

During the specific implementation, in order to distinguish whether it is a power module failure or an external failure, it is determined that the power module that has not failed itself can continue to detect the output voltage of the power system. If the output voltage of the power system is still abnormal when the last power module is inspected , it is determined that a fault outside the power system has occurred and the fault is reported. It can also not be determined directly, but output voltage to the power system again after the last power module inspection, and then perform the steps shown in Figure 2. After repeating this at least once, if the output voltage of the power system is still abnormal, then It is determined that a fault other than the power system has occurred and the fault is reported.

It can be seen that after the inspection of all power modules is completed, the entire power system will automatically resume normal operation.

In another preferred implementation of the present invention, intelligent identification and control of faults are performed according to the flow shown in FIG. 3 . As can be seen from Figure 3, for each power module, when the output voltage of the power system is detected to be abnormal, it first stops outputting voltage to the power system, that is to say, all power modules will stop supplying voltage to the power system. The output voltage. For a specific power module, it resumes normal operation and outputs voltage to the power system again when it reaches its own inspection time, that is to say, each power module resumes output voltage to the power system one by one .

Then, detect the current output voltage of the power supply system, and then judge whether the current output voltage is normal. If it is not normal, it is determined that a fault has occurred. At this time, the power module should report the fault situation and lock it through its own control circuit. , to completely break away from the entire power system. In the specific implementation, another processing method can also be selected. For the power module that is determined to have a fault, it does not immediately report the fault or perform lockout processing, but continues to detect the output voltage of the power system. When the power supply module is installed, the output voltage of the power system is still abnormal, that is, all the power modules believe that they have failed. In practice, this is almost impossible, so at this time it should be determined that a failure outside the power system (such as load failure) and report the failure situation. In a further solution, it is also possible not to directly identify an external fault, but to re-output the voltage to the power system after the last power module inspection, and then perform the aforementioned inspection steps. After repeating this for at least 1-3 times, if the power system If the output voltage of the power supply is still abnormal, it is determined that a fault outside the power supply system has occurred and the fault is reported.

If the current output voltage of the power supply system is normal, then the power module does not believe that it has failed itself. At this time, the power module had better wait for all the power modules to complete their own inspections before returning to normal work and reconnecting to the power supply. system output voltage. Because the current output voltage is normal, the normal operation can be resumed immediately for the power module that is determined not to have failed itself during actual implementation.

Claims (12)

1. the intelligent identification Method of a power system failure, comprise a plurality of power modules parallel with one another in the described power-supply system, it is characterized in that, each power module determines self to patrol and examine order according to own address signal in this power-supply system, again according to self patrol and examine order and default polling period, determine when detect output voltage unusual after startup self start-up time of patrolling and examining;

After the output voltage that detects power-supply system is unusual,, handle according to the following steps at each power module:

Step 1, when arriving self monitoring time, stop to described power-supply system output voltage;

The current output voltage of step 2, the described power-supply system of detection;

Step 3, judging whether the current output voltage of described power-supply system is normal, is that fault has taken place for oneself as normally then assert; As undesired, then assert own normal.

2. the intelligent identification Method of power system failure according to claim 1, it is characterized in that, in described step 1, described power module by the mode of closing its inner power conversion circuit and/or disconnecting the controlled release unit of its output to stop to described power-supply system output voltage; Described controlled release unit is relay or controlled tr tube.

3. the intelligent identification Method of power system failure according to claim 1, it is characterized in that, in described step 3, if described power module identification is that fault has taken place for oneself, then carry out locked processing, report failure condition simultaneously by self control circuit.

4. according to the intelligent identification Method of each described power system failure among the claim 1-3, it is characterized in that in described step 3, if the current output voltage of described power-supply system is undesired, then described power module identification is not oneself fault to have taken place; Wait for then that all power modules are all finished and recover operate as normal after self patrolling and examining again and again to described power-supply system output voltage.

5. the intelligent identification Method of power system failure according to claim 4, it is characterized in that, in described step 3, described identification is not that the output voltage that the power module of fault continues to detect described power-supply system has taken place oneself, if the output voltage of described power-supply system is still undesired when patrolling and examining last power module, then assert it is the fault outside the power-supply system to have taken place and reported failure condition.

6. the intelligent identification Method of power system failure according to claim 4, it is characterized in that, in described step 3, described identification is not that the output voltage that the power module of fault continues to detect described power-supply system has taken place oneself, if the output voltage of described power-supply system is still undesired when patrolling and examining last power module, again to described power-supply system output voltage, carry out described step 1 then after then in the end a power module has been patrolled and examined to step 3; After so repeating at least once,, then assert it is the fault outside the power-supply system to have taken place and reported failure condition if the output voltage of power-supply system is still undesired.

7. the intelligent identification Method of a power system failure, comprise a plurality of power modules parallel with one another in the described power-supply system, it is characterized in that, each power module determines self to patrol and examine order according to own address signal in this power-supply system, again according to self patrol and examine order and default polling period, determine when detect output voltage unusual after startup self start-up time of patrolling and examining;

After the output voltage that detects power-supply system is unusual,, handle according to the following steps at each power module:

The first step, stop to described power-supply system output voltage earlier, when arriving self monitoring time, then recover operate as normal, again to described power-supply system output voltage;

The current output voltage of second step, the described power-supply system of detection;

The 3rd step, judging whether the current output voltage of described power-supply system is normal, is that fault has taken place for oneself as undesired then identification, and stops once more to described power-supply system output voltage; Oneself do not break down as normally then assert, keep operate as normal.

8. the intelligent identification Method of power system failure according to claim 7, it is characterized in that, in the described first step with in the 3rd step, described power module by the mode of closing its inner power conversion circuit and/or disconnecting the controlled release unit of its output to stop to described power-supply system output voltage; Described controlled release unit is relay or controlled tr tube.

9. the intelligent identification Method of power system failure according to claim 7, it is characterized in that, in described the 3rd step, if described power module identification is that fault has taken place for oneself, then also carry out locked processing, report failure condition simultaneously by self control circuit.

10. the intelligent identification Method of power system failure according to claim 7, it is characterized in that, in described the 3rd step, the output voltage of the described power-supply system of power module continuation detection of fault oneself has taken place in described identification, if the output voltage of described power-supply system is still undesired when patrolling and examining last power module, then assert it is the fault outside the power-supply system to have taken place and reported failure condition.

11. the intelligent identification Method of power system failure according to claim 7, it is characterized in that, in described the 3rd step, the output voltage of the described power-supply system of power module continuation detection of fault oneself has taken place in described identification, if the output voltage of described power-supply system is still undesired when patrolling and examining last power module, then in the end a power module has been patrolled and examined afterwards again to described power-supply system output voltage, carry out described three steps of the first step to the then, after so repeating at least once, if the output voltage of power-supply system is still undesired, then assert it is the fault outside the power-supply system to have taken place and reported failure condition.

12. intelligent identification Method according to each described power system failure among the claim 7-11, it is characterized in that, in described the 3rd step, if the current output voltage of described power-supply system is normal, then described power module identification is not oneself fault to have taken place, stop once more to described power-supply system output voltage, wait for; Wait for then that all power modules are all finished and recover operate as normal after self patrolling and examining again and again to described power-supply system output voltage.

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