阅读说明：本技术 检查电力单元的方法 (Method for inspecting electric power unit ) 是由 吴志铭 林建宇 李宗勳 于 2020-05-11 设计创作，主要内容包括：本发明提出一种检查电力单元的方法,应用于通过信号母线连接的多个电力单元。方法是将电力单元断开信号母线,电力单元具有输出电流,经由控制器下达控制命令以调升输出电流,测量调升后的输出电流,并比较输出电流与控制命令所对应的目标电流值以决定电力单元来决定检查结果。本发明可有效缩短检查时间,并可提升检查精确度。(The invention provides a method for checking power units, which is applied to a plurality of power units connected through signal buses. The method comprises disconnecting a signal bus from a power unit, wherein the power unit has an output current, issuing a control command through a controller to increase the output current, measuring the increased output current, and comparing the output current with a target current value corresponding to the control command to determine the power unit to determine an inspection result. The invention can effectively shorten the inspection time and improve the inspection accuracy.)

1. A method of inspecting electrical power units, wherein a plurality of electrical power units are connected by a signal bus, each of the electrical power units comprising a power module and a controller, the method comprising the steps of:

a) disconnecting one of the plurality of power units from the signal bus, wherein the power unit has an output current;

b) sending a control command through the controller to increase the output current;

c) measuring the output current after the boost; and

d) comparing the output current with a target current value corresponding to the control command to determine a checking result of the power unit.

2. The method of inspecting a power unit of claim 1, further comprising the steps of:

e) selecting one of the plurality of power units not having the checking result to execute the step a) to the step d).

3. The method of inspecting a power unit of claim 1, further comprising, before the step b), the steps of:

f1) performing a status detection of the power unit;

f2) when any error is detected, the execution of the steps a) to d) is skipped and a notification is output.

4. The method of inspecting a power unit of claim 1, wherein the step d) comprises the steps of:

d1) when the output current reaches the target current value, determining that the inspection result of the power unit is normal; and

d2) when the output current does not reach the target current value, the checking result of the power unit is judged to be abnormal.

5. The method of inspecting a power unit of claim 1, wherein the step d) comprises the steps of:

d3) judging whether the checking result of the power unit is normal or not according to the output current when a passing condition is met; and

d4) and judging that the checking result of the power unit is abnormal according to the output current when the passing condition is not met.

6. The method of claim 5, wherein the pass condition comprises the output current reaching the target current value within a reaction time, the output current reaching the target current value for a target duration, or the number of times the output current reaches the target current value in multiple measurements reaching a target number.

7. The method of claim 6, wherein different types of the power units correspond to different reaction times, different target durations, or different target times, respectively.

8. The method of claim 6, wherein the pass condition further comprises the output current being less than a rated current value of the power unit, the rated current value being greater than the target current value.

9. The method according to claim 6, wherein the response time is less than 0.5 seconds, and the target current value is greater than 80% of a rated current value of the power unit.

10. The method of inspecting a power unit of claim 5, wherein the step d4) includes the steps of:

d41) judging whether the checking result of the power unit is abnormal according to the output current when the passing condition is not met but an ending condition is met; and

d42) and c), judging according to the output current, and executing the step c) again when the passing condition is not met and the ending condition is not met.

11. The method of claim 10, wherein the end condition comprises passing a limit time or repeating measurements for a limit number of times; the limiting time is longer than a response time and a target duration, and the limiting times is longer than a target times.

12. The method of claim 1, wherein the signal bus is a current share bus, each of the power units further comprises a current control loop and a voltage control loop connected to each other, the controller directly connects the current control loop and the voltage control loop, the signal bus is connected to the current control loop via a switch;

the step a) is to open the switch to disconnect the power unit from the signal bus.

13. The method according to claim 12, wherein the step c) measures a current value of an output terminal of the power unit as the output current of the power unit, and inputs a sensing signal of the output current to the current control loop.

14. The method of claim 1, wherein the power unit is a power supply, the power module further comprises a power stage; the step d) is to compare the output current with the target current value corresponding to the power supply.

15. The method of claim 1, wherein the power module is a battery module and includes a battery and a dc-dc converter; the step d) is to compare the output current with the target current value corresponding to the battery or the DC-DC converter.

Technical Field

The present invention relates to power units, and more particularly to inspecting power units.

Background

The power unit check mainly checks whether the output current of the power unit can reach an expected current value to judge whether the performance of the power unit is normal or abnormal. In addition, the conventional inspection method mainly changes the output current by adjusting the voltage to test whether the upper limit of the output current can reach the expected current value.

However, the conventional inspection method has problems of too long inspection time, too low inspection accuracy, and easily triggering over-current protection of the power unit during inspection.

In addition, in the prior art, a plurality of power units are connected in parallel to obtain a higher output current. In addition, since the voltages of the power units are not completely the same, a current sharing technique has been proposed, in which a plurality of power units are connected in parallel through a signal bus to share the current among the power units, so as to provide the same output current.

However, when the signal bus is provided, the current inspection method cannot adjust the output current by adjusting the voltage because the signal bus provides the effect of forced current equalization.

Therefore, the existing inspection methods have the above problems, and a solution to be more effective is urgently proposed.

Disclosure of Invention

The main objective of the present invention is to provide a method for checking a power unit, which can directly issue a control command to increase the output current to check the performance of the power unit.

To achieve the above object, the present invention provides a method for inspecting power units, wherein a plurality of power units are connected via a signal bus, each power unit comprises a power module and a controller, the method comprises the following steps: disconnecting one of the plurality of power units from the signal bus, wherein the power unit has output current; sending a control command through the controller to regulate and increase the output current; measuring the output current after the boost; and comparing the output current with a target current value corresponding to the target control command to determine a checking result of the power unit.

The invention can effectively shorten the inspection time, improve the inspection accuracy and eliminate the influence of the current sharing technology.

Drawings

Fig. 1 is an architecture diagram of a power unit.

Fig. 2 is a graph of voltage command versus time and output current versus time for a power unit based on a prior art performance check.

Fig. 3 is an architecture diagram of the power equipment.

Fig. 4 is an architecture diagram of the power equipment according to the first embodiment of the present invention.

Fig. 5 is an architecture diagram of a power plant according to a second embodiment of the present invention.

Fig. 6 is an architecture diagram of a power plant according to a third embodiment of the present invention.

Fig. 7 is an architecture diagram of a power plant according to a fourth embodiment of the present invention.

Fig. 8 is a flowchart of a method of checking a power unit according to a first embodiment of the present invention.

Fig. 9 is a partial flowchart of a method of inspecting a power unit according to a second embodiment of the present invention.

Fig. 10 is a flowchart of a method of checking a power unit according to a third embodiment of the present invention.

Fig. 11 is a flowchart of a method of checking a power unit according to a fourth embodiment of the present invention.

Fig. 12 is a partial flowchart of a method of checking a power unit according to a fifth embodiment of the present invention.

Fig. 13 is a graph of output voltage versus time and a graph of output current versus time for a power unit with normal performance according to the present invention.

FIG. 14 is a graph of output voltage versus time and a graph of output current versus time for an abnormal performance power unit according to the present invention.

Wherein the reference numerals are as follows:

10 power unit

100 power module

101 voltage control loop

102 current control loop

103, output terminal

11: power unit

12: signal bus

13, output end

20 power unit

200 power module

201 electric power control module

202 control command module

203, switch

21: signal bus

22: output terminal

30, a controller

31 voltage control loop

32 current control loop

40 power unit

41 signal bus

42 output end

400 power stage

401 controller

402. 404 differential amplifier 405 switch

403. 406 overlap circuit

50. 53 electric power unit

51 signal bus

52 output terminal

500 battery

501 DC-DC converter

60-62 voltage variation

I_out、I_{out_1}、I_{out_2}…I_{out_n}Output current

I_{out_sense}Output current sensing signal

I_{share_com}Current-sharing control signal

I_RatedRated current

I_COMControl command

I_THTarget current value

t is time

T1, T2, T3 time interval

T_DisconnectTime of disconnection

T_CheckChecking time

T_ConnectConnection time

T_Re-tryRetry time

Δ V voltage variation

V_RefReference voltage

V_{in_1}、V_{in_2}、V_{in_n}Input voltage

V_out、V_{out_1}、V_{out_2}…V_{out_n}Output voltage

V_EAError voltage

V_FBFeedback voltage

S10-S13: first inspection step

S20-S22: switching step

S30-S38: second inspection step

S40-S47: a third inspection step

S50-S51: step of current sharing

Detailed Description

The following detailed description of a preferred embodiment of the present invention will be made with reference to the accompanying drawings.

Referring to fig. 1 to 3, fig. 1 is an architecture diagram of a power unit, fig. 2 is a voltage command-time relationship diagram and an output current-time relationship diagram of the power unit based on a conventional performance check, and fig. 3 is an architecture diagram of a power device.

Fig. 1 to 3 are diagrams for more specifically illustrating the problem to be solved by the present invention and the lack of the conventional inspection method.

As shown in fig. 1, the power unit 10 may include a power module 100, a voltage control loop 101, a current control loop 102 and an output terminal 103, which are electrically connected.

The conventional performance check is to adjust the reference voltage V to the voltage control loop 101_RefSo as to boost the output voltage of the power unit 10, and the output current I of the output terminal 103_outAnd will also be lifted accordingly.

However, since the performance of the power unit 10 is not known before the inspection, it is not possible to directly select the most appropriate reference voltage V_Ref. In particular, when reference voltage V_RefWhen too high, it will cause the output current I_outToo high, this may trigger an Over Current Protection (OCP) mechanism to automatically shut down the power unit 10 and cause the inspection failure.

In contrast, as shown in FIG. 2, the conventional performance check is performed from a lower reference voltage V_RefThe slow ramp-up was started. For example, each time the voltage is raised by Δ V, and the time interval T1 seconds (e.g. 10 seconds) is waited after the raising if the output current I is outputted_outDoes not reach the rated current I_RatedThen the voltage change Δ V is regulated up again until the output current I_outTo reach rated current I_Rated(Normal Performance) or reference Voltage V_RefThe maximum value of the possible ramp-up (performance anomaly) is reached.

The above-mentioned inspection method has an excessively long inspection time (the reference voltage V is adjusted every time)_RefLater waiting for current change), checking accuracy is too low(the check result may be abnormal because the proper reference voltage V is not properly applied_RefOutput current I when the result of the check is normal_outPossibly caused by a current surge) and over-current protection (such as a current surge) of the power unit is easily triggered during the inspection.

In addition, as shown in fig. 3, when a plurality of power units 11 are connected in parallel inside the power equipment, and the current sharing control signal terminal of each power unit 11 is coupled to a signal bus 12, the power units 11 provide the same and stable output current due to the current sharing effect, which makes the conventional inspection method unable to be used for the power equipment with the signal bus.

To solve the above problems, the present invention provides a power device and a method for checking a power unit for the power device, which can perform performance check on a power device having a signal bus (e.g., a current sharing bus) based on current control, can accurately adjust an output current, and does not trigger an overcurrent protection mechanism.

Fig. 4 is a schematic diagram of an electrical apparatus according to a first embodiment of the present invention. As shown in fig. 4, the power apparatus of the present invention includes a plurality of power units 20, the output ends of the power units 20 are connected in parallel, and the current sharing control signal ends of the power units 20 are all coupled to a signal bus 21. Through the signal bus 21, the power device can provide a stable power output (i.e. provide a stable output voltage and output current) at the output terminal 22 (such as a cable, an electrical connector or an electrical connection terminal, etc.).

Each power unit 20 includes a power module 200 and a power control module 201 electrically connected to each other.

The power module 200 (which may include a battery and/or a device for external power) is used to provide power. The power control module 201 (which may include a microprocessor and other electronic circuits) is used to adjust the output power (e.g., output voltage and/or output current) of the power module 200.

In the present invention, the power control module 201 includes a controller 30. The controller 30 is configured to issue a control command to the power control module 201 to adjust the output current of the power module 200. The control command is a set of control signals corresponding to a set of target current values, and is used to control the power control module 201 to adjust the output current of the power module 200 to the target current value specified by the control command.

In the present invention, the power unit 20 further includes a switch 203 for connecting the signal bus 21 and the power control module 201. The power control module 201 can control the switch 203 to be turned on or off, so that the power unit 20 is connected to the signal bus 21 to obtain the current sharing effect, or the signal bus 21 is disconnected to eliminate the current sharing effect.

Therefore, the present invention can eliminate the current sharing effect of the power unit 20 via the switch 203, and can perform the performance check.

Fig. 5 is a schematic diagram of an electrical apparatus according to a second embodiment of the present invention. In the embodiment of fig. 5, the power control module 201 may include a controller 30, a voltage control loop 31 and a current control loop 32 electrically connected to each other. V_outIs the power output terminal.

The controller 30 is used to control the output voltage and the output current of the power module 200, and can monitor the performance of the power module 200. The voltage control circuit 31 is used for adjusting the output voltage of the power module 200. The current control loop 32 is used to adjust the output current of the power module 200.

Specifically, the controller 30 includes a control command module 202, the current control loop 32 is connected to the controller 30, and the controller 30 can generate and execute the control command via the control command module 202. The current control circuit 32 is further connected to a switch 203 (the controller 30 can control the switch 203), and is connected to the signal bus 21 via the switch 203 to enable or disable the current sharing effect.

In one embodiment, the controller 30 may include a memory (e.g., a temporary memory, a Read Only Memory (ROM), a flash memory, or other non-transitory storage medium). The aforementioned memory may store a set of correspondences between a plurality of different control commands and a plurality of different target current values. The different target current values correspond to different types of power units 20 or different types of power devices, respectively. The controller 30 may select a corresponding target current value according to the type (such as model, performance, etc.) of the power unit 20 or the power device, and generate a corresponding control command, i.e., a control command for adjusting the output current of the power module 200 to the target current value, based on the corresponding relationship.

In one embodiment, the correspondence relationship may be generated through repeated experiments, calculations and statistics based on the characteristics of different types of power devices or power modules 200, and is pre-written into the memory of the controller 30 before the power devices are shipped. Therefore, each control command can accurately control the corresponding type of power device or power module 200 to adjust the output current to the corresponding target current value.

In one embodiment, the correspondence is recorded in a lookup table, and the lookup table is stored in the memory.

In one embodiment, the controller 30 is connected to the current control loop 32 through a signal line, and the control command module 202 is a software control module (e.g., a computer program) or a circuit control module disposed in the controller 30.

It should be noted that the voltage control circuit 31 and the current control circuit 32 are interlocked, that is, when the voltage control circuit 31 changes the output voltage V of the power unit 20_outWhen the output current is further changed, the current control loop 32 will respond to the change of the output current (e.g. a set of signals corresponding to the output current, such as the output current sensing signal I in FIGS. 6 and 7)_{out_sense}Fed back to the current control loop 32) to affect the voltage control loop 32 and thereby change the output voltage V_out. Through the mode, the invention can accurately adjust the output current to the target current.

Fig. 6 is a schematic diagram of an electrical apparatus according to a third embodiment of the present invention. The controller 401 is the same as or similar to the controller 30 described above and will not be described in detail herein.

In the embodiment of fig. 6, each of the power units 40 is a power supply, the power module 200 may include a power stage 400(power stage) electrically connected to a controller 401 (the controller 401 is the same as or similar to the controller 30), and the power stage 400 is used for connecting an input terminal (i.e., the input voltage V) to the power module_{in_1}、V_{in_2}…V_{in_n}) Is/are as followsPower conversion to match output 42 (connected output voltage V)_{out_1}、V_{out_2}…V_{out_n}) Such as a specified output voltage or output current.

The aforementioned input terminal (including input voltage V)_{in_1}、V_{in_2}、V_{in_n}) Which may be a cable, electrical connector or electrical connection, etc., and may be connected to a source of electrical power (e.g., mains electricity or a generator) to obtain an electrical power input.

In the present embodiment, each power unit 40 has an output current I_{out_1}、I_{out_2}…I_{out_n}And respectively have an output voltage V_{out_1}、V_{out_2}…V_{out_n}。

Also, the current control loop 32 includes an overlap circuit 406 and a differential amplifier 404. The signal bus 41 is connected to the superimposing circuit 406 and to the differential amplifier 404 via the switch 405.

It should be noted that, in the present embodiment, the control command I_COMAn output current sensing signal I_{out_sense}Current-sharing control signal I_{share_com}The signal bus signal can be realized by an analog voltage signal, but the purpose is to regulate the output current I_{out_1}、I_{out_2}…I_{out_n}. For example, the present embodiment may represent the current value to be transmitted by an analog voltage signal (such as the reading of the output current or the current average value of the signal bus, etc.).

Moreover, the plurality of control commands may be different analog voltage signals (i.e., the memory may record a corresponding relationship between the voltage signals with different voltage values and different target current values, for example, the target current value corresponding to the voltage signal of 1.2V is 50A), and the embodiment may select a correct voltage signal (i.e., the control command) for the current power equipment to accurately and quickly adjust the output current to the target current value.

It is worth mentioning that in different types of power devices, the same control command voltage may correspond to different target current values. For example, a voltage signal of 1.2V corresponds to a target current value of 50A in the first power device, but may correspond to a target current value of 30A in the second power device.

The following illustrates a specific operation of the present invention.

When the switch 405 is turned on, the signal bus 41 connects the output current sensing signals I of the plurality of power units 40_{out_sense}(output current sense signal I of each power unit 40 thereof_{out_sense}May be the output current I of the power unit 40_{out_1}、I_{out_2}…I_{out_n}E.g. the output current I of each power unit 40_{out_1}、I_{out_2}…I_{out_n}As the aforementioned output current sensing signal I_{out_sense}Fed back to the current control loop 32) and may generate a signal bus signal. The signal bus signal and the output current sensing signal I of each power unit 40_{out_sense}After being overlapped by the overlapping circuit 406, the current sharing control signal I indicating the average value of the currents of the plurality of power units 40 can be generated_{share_com}. Then, the current-sharing control signal I_{share_com}And output current sense signal I_{out_sense}The processed result (which may be a voltage signal) from the differential amplifier 404 may be input to the voltage control loop 31 to adjust the output voltage V_{out_1}、V_{out_2}…V_{out_n}And correspondingly changing the output current I_{out_1}、I_{out_2}…I_{out_n}。

When the switch 405 is open, the signal bus 41 is removed from the current control loop 32 (i.e. the current sharing control signal I)_{share_com}Removed), the newly introduced control command I of the present invention_COMDirect and output current sensing signal I_{out_sense}The processed result (which may be a voltage signal) from the differential amplifier 404 may be input to the voltage control loop 31 to adjust the output voltage V_{out_1}、V_{out_2}…V_{out_n}And correspondingly changing the output current I_{out_1}、I_{out_2}…I_{out_n}。

Further, the voltage control loop 31 includes an overlap circuit 403 and a differential amplifier 402. In the present embodiment, the power unit 40 is controlled by: the difference is put according to the preset weight pairsThe processing result of the amplifier 404 (when the switch 405 is turned on, the processing result is the current sharing control signal I_{share_com}And output current sense signal I_{out_sense}The error value of (1); when the switch 405 is open, the processing result is the control command I_COMAnd output current sense signal I_{out_sense}Error value), and a feedback voltage V_FBThe superposition process is performed by the superposition circuit 403, and then the processing result (which may be a voltage signal) of the superposition circuit 403 is superposed with the reference voltage V_RefCompared by a differential amplifier 402 to obtain an error voltage V_EAAnd is controlled by the controller 401 according to the error voltage V_EAControlling the output voltage V of the power unit 40_{out_1}、V_{out_2}…V_{out_n}And correspondingly adjusting the output current I_{out_1}、I_{out_2}…I_{out_n}。

It is worth mentioning that the conventional checking method is to ramp up the reference voltage V slowly for many times_RefTo gradually increase the output voltage V_{out_1}、V_{out_2}…V_{out_n}Further gradually increasing the output current I_{out_1}、I_{out_2}…I_{out_n}. The above-mentioned manner of changing the output current not only has a long response time, but also cannot expect the adjusted current value, and is easy to trigger the over-current protection mechanism.

Compared with the prior art, in the invention, the reference voltage V_RefMay be set to a fixed value (which may be determined based on the type of power equipment). The invention directly obtains the output current I of the power equipment to be checked through the corresponding relation_{out_1}、I_{out_2}…I_{out_n}Set of control commands I for rapidly and safely reaching a target current value_COM(analog voltage value), and after the switch 405 is turned off, the controller 401 issues the control command I directly through the control command module 202_COMTo the differential amplifier 404 to directly boost the output current I_{out_1}、I_{out_2}…I_{out_n}To the target current value.

Fig. 7 is an architecture diagram of a power apparatus according to a fourth embodiment of the present invention. In contrast to the embodiment of fig. 6, in the embodiment of fig. 7, the power unit 50 is an electric storage device (e.g., a backup battery device) and does not require power input.

The power module includes a battery 500 and a dc-dc converter 501. The battery 500 is used for storing and providing power, and the DC-DC converter 501 is used for converting the DC power of the battery 500 to meet the output voltage V_{out_1}And output a current I_{out_1}The dc power specification of (1).

In the present embodiment, the power unit 53 is a power supply, the power unit 50 and the power unit 53 are connected in parallel at the output end, and the current sharing control signal ends are both coupled to the signal bus 51. Therefore, when power is lost (i.e., the power unit 53 cannot obtain power), the power equipment of the present invention can continue to supply power through the power unit 50.

It should be noted that, although the power storage device is described in conjunction with the power supply in the present embodiment, the present invention is not limited thereto. In another embodiment, all the power units 50 of the power plant may be changed to the power storage device.

Fig. 8 is a flowchart illustrating a method for checking a power unit according to a first embodiment of the invention. The method for checking the power unit according to the embodiments of the present invention (hereinafter, referred to as the method) may be implemented by the power equipment according to any one of the embodiments shown in fig. 4 to 7 (which will be described later with reference to the embodiment of fig. 5).

Furthermore, the method of the embodiments of the present invention can be implemented by a hardware method (e.g., a circuit board, an integrated circuit, or an SoC) or a software method (e.g., a computer program such as firmware or an application program), which is not limited thereto. When implemented in software, the controller may include a non-transitory computer readable medium storing a computer program, and when the controller executes the computer program, the controller may control the power device to perform the following steps.

Specifically, the method of the present embodiment includes the following steps.

Step S10: the controller 30 of one of the power units 20 (controlled by the external or automatically triggered) controls the disconnection of the power unit 20 from the signal bus 21 (e.g., via the disconnection switch 203), so that the output current of the power unit 20 can eliminate the current sharing effect.

Step S11: the controller 30 issues a control command via the control command module 202 and executes the control command. The control command is used to control the output current of the power unit 20 to be adjusted to the target current value corresponding to the power unit 20. The aforementioned target current value may be set based on the rated current of the power unit 20, such as 80% rated current, 90% rated current, 97% rated current, or the like, without limitation.

It is worth mentioning that, in general, the performance of the power unit gradually degrades with use. Moreover, even if the output current of the power unit cannot reach 100% of the rated current, the power unit can still be used continuously to save the maintenance cost as long as the degradation is not serious (for example, the maximum output current is more than 80% of the rated current).

In addition, even if the power unit is completely new, the power unit can still be used normally even though the performance of the power unit cannot reach 100% of rated current due to problems such as inconsistent manufacturing processes or yield, or damaged transportation.

Therefore, if the target current value is directly set to 100% of the rated current, the available power unit is erroneously determined to be abnormal and must be replaced, which increases the maintenance cost. In contrast, the present invention sets the target current value to be close to but less than the rated current, and can effectively avoid the above-mentioned problem of misjudging the available power unit as abnormal.

In one embodiment, the user can connect to the control command module 22 through an external computer and operate the external computer to issue a control command to the controller 30.

In one embodiment, after the power unit 20 is switched to the checking mode (automatically or manually by a user), the controller 30 may execute the control command module 202 to read a control command pre-stored in the memory (e.g., after determining the target current value, a control command corresponding to the determined target current value is obtained based on the correspondence between the control command and the target current value), and issue the control command automatically.

Then, the current control loop 32 immediately reacts based on the control command and tries to quickly adjust the output current to the target current value, and the specific adjustment manner is as described in the related description of fig. 3 to fig. 7, which is not described herein again.

Step S12: the output current of the controller 30 to the power unit 20 (the output current I shown in FIG. 6 or FIG. 7)_out) The measurement is performed.

In one embodiment, the controller 30 measures a current value at the output terminal of the power module 20 as the output current.

Step S13: the controller 30 compares the measured output current with a target current value to determine the inspection result of the power unit 20.

In one embodiment, as shown in fig. 6, when the power unit is a power supply, the controller 30 compares the output currents I_{out_1}、I_{out_2}…I_{out_n}A target current value corresponding to the power supply (e.g., 90% of the rated current of the power supply).

In one embodiment, as shown in fig. 7, when the power module is a battery module (i.e. includes a battery 500 and a dc-dc converter 501), the controller 401 compares the output current I_{out_1}、I_{out_2}…I_{out_n}A target current value corresponding to the battery 500 or the dc-dc converter 501 (e.g., 98% of the rated current of the battery 500 or the dc-dc converter 501).

The invention can effectively shorten the inspection time, improve the inspection accuracy and eliminate the influence of the current sharing technology.

Referring to fig. 9, a partial flowchart of a method for checking a power unit according to a second embodiment of the invention is shown. Compared to the embodiment shown in fig. 8, the method of the present embodiment provides an automatic switching function, which can automatically switch to check a plurality of power units 20 of the power equipment. Specifically, the method of the present embodiment includes the following steps.

Step S20: the external test program (the external test program may be installed in an external test computer, and the external test computer (connected to the controller 30 of each power unit 20) is connected to the controller 30) or the controller 30 selects one of the power units 20 that are not checked (i.e. selects the power unit 20 that does not have the check result), such as the first selected power unit 20, or selects the power unit 20 that is the longest from the last check, etc., without limitation.

Step S21: the controller 30 performs the performance check of the present invention, such as performing steps S10-S13 shown in FIG. 8, steps S30-S38 shown in FIG. 10, or steps S40-S47 shown in FIG. 11.

In the performance check, the switch 203 is controlled to be open-circuited to disconnect the selected power unit 20 from the signal bus 21, issue and execute a control command to the selected power unit 20, measure the output current of the selected power unit 20, and determine the performance of the selected power unit 20 based on the output current after the reaction.

Step S22: after the selected power unit 20 completes the performance check, the external test program or controller 30 determines whether there are other power units 20 to be checked.

If there are other power units 20 to be checked, step S20 is executed again to select another power unit 20 for performance checking. Otherwise, the check of the power equipment is ended.

Therefore, the invention can automatically check a plurality of power units of the same power equipment, save the operation of manually switching the power units by a user and reduce the total checking time.

Referring to fig. 10, a flowchart of a method for checking a power unit according to a third embodiment of the invention is shown. The method of the present embodiment will be described with reference to the power device shown in fig. 6, but it should be understood by those skilled in the art that the method of the present embodiment can be implemented by using any one of the power devices shown in fig. 4 to 7.

The method of this embodiment further provides a status checking function (steps S31-S32), which checks whether the power equipment (including the power unit 40) can operate normally before performing the performance check on the output current, so as to avoid the abnormal power equipment causing the error of the performance check result. Specifically, the method of the present embodiment includes the following steps.

Step S30: the controller 401 opens the switch 405 to disconnect the power unit 40 from the signal bus 41, so that the current sharing effect of the power unit 40 is lost.

Step S31: the controller 401 performs device status detection to detect whether the power device or the power unit 40 can operate normally. The device status detection may include, but is not limited to, detecting whether a circuit element is faulty (e.g., over-current, abnormal contact or resistance), detecting whether a sensor is faulty, and the like.

Step S32: the controller 401 determines whether an error (e.g., any one of the components is malfunctioning, or the output voltage/current values are abnormal, etc.) is detected.

If the controller 401 detects any error, step S37 is executed: the controller 401 stops the performance check this time and may output a notification (e.g., a performance check non-execution notification).

If the controller 401 does not detect an error, step S33 is executed: issues and executes a control command I_COM. Then, output current I_{out_1}As a result of the execution of the control commands.

Step S34: controller 401 responds to the output current I_{out_1}The measurement is performed.

Step S35: the controller 401 determines the output current I_{out_1}Whether the preset target current value is reached or not is judged to determine the checking result of the performance checking.

If the current I is output_{out_1}When the target current value is reached, the controller 401 executes step S36: the controller 401 determines that the checking result of the power unit is performance normality, and may further output a notification (e.g., a performance normality notification).

At the output current I_{out_1}When the target current value is not reached, the controller 401 executes step S38: the controller 401 determines that the result of the check of the power unit 40 is a performance abnormality, and may further output a notification (e.g., a performance abnormality notification).

Therefore, the present invention can effectively determine the inspection result of the performance inspection of the power unit 40 based on whether the output current reaches the target current value.

It should be noted that in the present embodiment, the signal bus 41 is disconnected (step S30) first, and then the state detection is performed (steps S31-S32), but the present invention is not limited thereto.

In another embodiment, the present embodiment may be modified to perform the status check (steps S31-S32) and then disconnect the bus bar 41 (step S30) after no error is detected.

In another embodiment, the present embodiment may be modified to perform the state detection (steps S31-S32), and after no error is detected, disconnect the signal bus 41 (step S30), and perform a different state detection (i.e., perform steps S31-S32 again).

Referring to fig. 11, a flowchart of a method for checking a power unit according to a fourth embodiment of the invention is shown. The method of the present embodiment will be described with reference to the power device shown in fig. 7, but it should be understood by those skilled in the art that the method of the present embodiment can be implemented by using any one of the power devices shown in fig. 4 to 7.

Compared to the embodiment of fig. 10, which determines the performance of the power unit directly based on whether the output current reaches the target current value, the embodiment may allow the user to set more precise passing conditions and ending conditions to confirm the performance more accurately. Specifically, the method of the present embodiment includes the following steps.

Step S40: the controller 401 controls the switch 405 to open to disconnect the power unit 50 from the signal bus 51.

Step S41: the controller 401 performs status detection on the power devices (including the power unit 50). The state detection of this embodiment may be the same as or similar to the state detection of fig. 10, and is not described herein again.

Step S42: issues and executes a control command I_COM. Then, output current I_{out_1}As a result of the execution of the control commands.

Step S43: controller 401 responds to the output current I_{out_1}The measurement is performed.

Step S44: the controller 401 determines whether the output current (including the current variation and the variation amplitude) satisfies a predetermined passing condition.

In one embodiment, the passing condition may include an output current I_{out_1}At reaction times (e.g. 200 ms, reverse)The response time may be set according to the type of the power unit 50) to reach a target current value (e.g., 85% of the rated current), i.e., different types of power units 50 may correspond to different response times, respectively.

In one embodiment, the passing condition may include an output current I_{out_1}The target current value is continuously reached for a target duration (e.g., 200 ms, the target duration may be set according to the type of the power unit 50), that is, different types of power units 50 may correspond to different target durations, respectively.

In one embodiment, the reaction time is less than 0.5 seconds.

In one embodiment, the passing condition may include an output current I_{out_1}The target current value is reached a target number of times (e.g., 90% of the times, i.e., 90 times, the target number of times may be set according to the type of the power unit 50) in a plurality of measurements (e.g., 100 times), that is, different types of power units 50 may correspond to different target numbers of times, respectively.

In one embodiment, the passing condition may include an output current I_{out_1}Is smaller than the rated current of the power unit 50, and the rated current value is larger than the target current value.

In one embodiment, the target current value is greater than 80% of the rated current value.

In one embodiment, the passing condition may include an output current I_{out_1}Not less than the target current value and less than the rated current value.

If the controller 401 determines that the output current satisfies the predetermined passing condition, step S45 is executed: the controller 401 determines that the power unit 50 passes the performance check, determines that the result of the performance check of the power unit 50 is normal, and outputs a response notification or makes a record.

If the controller 401 determines that the output current does not satisfy the predetermined passing condition, step S46 may be executed: the controller 401 determines whether the end condition is satisfied.

In one embodiment, the end condition may include a time limit (e.g., 1 second).

In one embodiment, the limit time is greater than the reaction time and the target duration.

In one embodiment, the end condition may include repeating the measurement for a limited number of times (e.g., 300 times).

In one embodiment, the limit number is greater than the target number.

If the controller 401 determines that the end condition is not satisfied, it performs step S41 again to determine again.

In one embodiment, if the controller 401 determines that the end condition is not satisfied, step S42 is executed again (i.e., the status detection is skipped).

If the controller 401 determines that the end condition is satisfied but the pass condition is not satisfied, it executes step S47: the controller 401 determines that the power unit 50 fails the performance check, determines that the result of the check of the power unit 50 is a performance abnormality, and may further output a notification or make a record.

Therefore, compared with the performance determination based on the single inspection result, the performance inspection is determined according to the results of multiple inspections, and the accuracy of the inspection can be effectively improved.

Referring to fig. 13 and 14 together, fig. 13 is a graph of output voltage-time relationship and output current-time relationship of a power unit with normal performance according to the present invention, and fig. 14 is a graph of output voltage-time relationship and output current-time relationship of a power unit with abnormal performance according to the present invention.

In the present example, the pass condition is the output current I_outReach the target current value I_THAnd lasts for an interval T2 (e.g., 300 milliseconds). The end condition being the output current I_outThe duration interval T3 (e.g. 1.5 seconds) does not reach the target current value I_TH。

As shown in fig. 13, in the example of passing the performance check, the power unit takes the off time T_DisconnectDisconnecting the signal bus, and receiving the control command to increase the current to exceed the target current value I_THAnd continuously checking for time T_CheckAnd is judged to be normal (continued check time T)_CheckReaching time interval T2). Then, the power unit takes the connection time T_ConnectReconnecting the signal bus to completeAnd (6) checking.

In the present example, the minimum inspection time is the off time T_DisconnectChecking time T_CheckAnd a connection time T_ConnectThe total time of (a) is generally far less than 10 seconds, and far less than the time required by the conventional inspection method.

As shown in fig. 14, in the case of the performance abnormality, the power unit takes the off time T_DisconnectDisconnecting the signal bus, receiving the control command to increase the current to exceed the checking time T_CheckThe target current value I is not reached yet_THAt retry time T_Re-tryInner continuous trying if retry time T_Re-tryThe output current can not reach the target current value I after passing through_TH(and continues for time interval T2), it is determined that the performance is abnormal. Then, the power unit takes the connection time T_ConnectThe signal bus is reconnected to complete the inspection.

In this example, the longest time required for inspection is the off time T_DisconnectRetry time T_Re-tryAnd a connection time T_ConnectThe total time (generally speaking, the total time is still far less than 10 seconds), which is far less than the time required by the conventional inspection method.

Referring to fig. 12, a partial flowchart of a method for checking a power unit according to a fifth embodiment of the invention is shown. The method of the present embodiment will be described with reference to the power device shown in fig. 4, but it should be understood by those skilled in the art that the method of the present embodiment can be implemented by using any one of the power devices shown in fig. 4 to 7. The method of this embodiment further illustrates how to use the signal bus to provide power stably, as compared to the method shown in fig. 8-11. Specifically, the method of the present embodiment includes the following steps in the operating mode.

Step S50: the power control modules 201 in each power unit 20 are connected to the signal bus 21, and the control switch 203 is turned on. After the connection is established, each power unit 20 outputs an output current (I shown in fig. 6 or 7) to the output terminal 22_{out_1}、I_{out_2}…I_{out_n}) Can achieve the effect of uniform currentThe result is converted to an average value of the currents of the plurality of power units 20.

Step S51: the power output end 22 of the power device outputs the power of the plurality of power units 20 after the current equalizing process, wherein the total output current is the sum of the output currents of the power units 20.

Therefore, the present invention can provide stable power output.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, so that equivalent variations using the teachings of the present invention are all included within the scope of the present invention, and it is obvious that the present invention is not limited thereby.