JP2019193336A - Power supply system - Google Patents

Abstract

To provide a power supply system capable of performing abnormality processing such as backup operation or alarm by detecting stop of a power supply unit due to failure using one or more other power supply units in a normal state and notifying a control/monitor section thereof.SOLUTION: In a power supply system comprising multiple power supply units PSU1-PSU3 connected in parallel and a control/monitor section 30 capable of transmitting a start/stop command to each of the power supply units, each of the power supply units includes a stop determination section 11 for determining stop of one or more other power supply units. Each of the stop determination sections 11 uses a unit measurement value measuring output of the own power supply unit and a load measurement value measuring power supplied to a load 50 by the multiple power supply units to calculate a deviation between a ratio of the unit measurement value and a ratio of the load measurement value that are changed within a predetermined value, determines the stop of the one or more other power supply units in a case where the deviation exceeds a predetermined threshold, and notifies the control/monitor section 30 thereof.SELECTED DRAWING: Figure 1

Description

  In the power supply system having a plurality of power supply units, the abnormality detection process and the backup can be performed when another power supply unit detects that one of the power supply units is stopped due to a failure and notifies the upper level. The present invention relates to a power supply system that can be operated.

FIG. 5 is a prior art of a power supply system having a plurality of power supply units connected in parallel, and is described in Patent Document 1.
In FIG. 5, 100A power supply unit operating as a master, 100B switching control circuit for controlling the power supply unit operating as a slave, 101A, 101B converter unit, 102A, 102B is a switching element _{Q 1,} 103A, 103B are droop generated circuit, 104A, 104B is an output voltage detection circuit, 105A is MCU (master), 105B are MCU (slave), 106A, the 106B output current detection circuit, _{V i} is the input voltage of the power supply system, _{V o} is the output voltage .

  As shown in FIG. 6A, the MCU (master) 105A includes a communication unit 111, an output current acquisition unit 112, a drive control unit 113, an addition unit 114, a number determination unit 115, connected to the MCU (slave) 105B. As shown in FIG. 6B, the MCU (slave) 105B includes an overcurrent protection unit 116 and a switch control unit 117. The communication unit 111, the output current acquisition unit 118, and the overcurrent protection unit 116B are connected to the MCU (master) 105A. A current protection unit 116 and a switch control unit 117 are provided.

In this prior art, in order to prevent a delay in starting the required number of power supply units when the load current increases rapidly and a part of the power supply units enter an overcurrent state, the master MCU 105A is configured as shown in FIG. It is working.
In FIG. 7, the MCU 105A detects its own output current via the output current acquisition unit 112 after the activation of the power supply unit 100A (steps S11 and S12), and if the detected current value is equal to or greater than the threshold value, the other power supply unit 100B. Etc. are driven (step S13 YES, S14). If the output current detection value is less than the threshold value, the output current of another power supply unit 100B or the like is acquired via the communication unit 111, and the load current is calculated by adding the output current to the own output current by the adding unit 114 ( Step S13 NO, S15).
Next, the MCU 105A determines the number of operating power supply units based on the calculated load current, and drives / stops the other power supply unit 100B as a slave (steps S16 and S17).
The above process is repeatedly executed until the power supply of the entire power supply system is turned off. (Step S18).

Japanese Patent No. 6202196 (paragraphs [0015] to [0028], [0042] to [0049], FIGS. 1 to 3, FIG. 8, etc.)

5-7, for example, even if the converter unit 101B of the power supply unit 100B on the slave side is operating normally, there is an abnormality in the MCU (slave) 105B and the detected output current value of the converter unit 101B. May not be obtained accurately by the master-side power supply unit 100A.
In such a case, the master-side power supply unit 100A cannot appropriately calculate the load current based on the output current detection value of each power supply unit or determine the number of slave-side power supply units to be driven. In some cases, some power supply units are overloaded, resulting in device failure or destruction.

  Therefore, the problem to be solved by the present invention is that it is possible to determine the operation stop of any of the plurality of power supply units without depending on the transmission information from the stop unit, and to perform subsequent abnormal processing, backup processing, etc. It is to provide a power supply system that can be realized.

In order to solve the above-described problem, the invention according to claim 1 is a power supply system that supplies power to a load by a plurality of power supply units connected in parallel to each other, and can transmit a start / stop command to each power supply unit In a power supply system with a control and monitoring unit,
The power supply units each include a stop determination unit that determines stop of other power supply units in the power supply system,
The stop determination unit
Using the unit measurement value obtained by measuring the output of its own power supply unit and the load measurement value obtained by measuring the power supplied to the load by the plurality of power supply units, the unit measurement value changed within a predetermined time. A deviation between the ratio and the ratio of the load measurement value is calculated, and when the deviation exceeds a predetermined threshold, it is determined that the other power supply unit is stopped, and the stop determination signal is It transmits to a monitoring part, It is characterized by the above-mentioned.

  According to a second aspect of the present invention, in the power supply system according to the first aspect, the control / monitoring unit that has received the stop determination signal even though the stop command is not transmitted to the other power supply unit. A start command is transmitted to a startable power supply unit in the power supply system.

  According to a third aspect of the present invention, in the power supply system according to the second aspect, the control / monitoring unit that has received the stop determination signal transmits a start command to all the power supply units except the other power supply units. It is characterized by doing.

  According to a fourth aspect of the present invention, in the power supply system according to the second or third aspect, the control / monitoring unit that has received the stop determination signal detects that the other power supply unit has stopped due to a failure. And an alarm is generated.

  According to a fifth aspect of the present invention, in the power supply system according to any one of the first to fourth aspects, the threshold value is a ratio of the load measurement value changed within the predetermined time and the power supply system. And setting based on the total number of power supply units.

  The invention according to claim 6 is the power supply system described in any one of claims 1 to 5, wherein the unit measurement value and the load measurement value are electric power or current.

  The invention according to claim 7 is the power supply system described in any one of claims 1 to 6, wherein the power supply unit is a power converter that performs AC / DC conversion.

  According to the present invention, even when a power supply unit that has stopped due to a failure cannot directly report its own state to a higher-level control / monitoring unit, a stop determination signal for the power supply unit is controlled from another healthy power supply unit. It is possible to notify the monitoring unit. As a result, the control / monitoring unit can quickly perform backup processing that activates power supply units other than the failed unit and abnormal processing such as alarm generation, and prevents some power supply units from becoming overloaded. be able to.

1 is a configuration diagram of a power supply system according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the stop determination part and control / monitor part in embodiment of this invention. In embodiment of this invention, it is explanatory drawing of the determination operation | movement of the stop determination part according to the fluctuation pattern of a unit measured value and a load measured value. It is a figure which shows a unit measured value, a load measured value, etc. when the number of driving | operations reduces by the stop of a power supply unit. 1 is a configuration diagram of a power supply system described in Patent Document 1. FIG. It is a block diagram of MCU (master) and MCU (slave) in FIG. It is a flowchart which shows operation | movement of MCU (master) in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a power supply system according to this embodiment. In the figure, a power supply system PS includes three power supply units PSU1 and PSU2 that convert single-phase AC power on the secondary side of a transformer 42 connected to a three-phase power system 41 into DC power and supply it to a load 50. , PSU3, and these power supply units PSU1, PSU2, PSU3 are connected in parallel to each other.
Here, the number of power supply units may be any plural number.

On the output side of the power supply units PSU1, PSU2, and PSU3, unit output measuring units 21, 22, and 23 that measure output powers P ₁ , P ₂ , and P ₃ of each unit are provided. Further, a load measuring unit 20 that measures load power (total value of output power of each unit) L is provided between the common connection point on the output side of all units and the load 50.

The power supply units PSU1, PSU2, and PSU3 are provided with stop determination units 11, 12, and 13 that determine that the other power supply units are in a stopped state, respectively. The stop determination units 11, 12, and 13 include power measurement values (hereinafter referred to as unit measurement values) P ₁ , P ₂ , and P ₃ by the corresponding unit output measurement units 21, 22, and 23 and a load measurement unit 20. A power measurement value (hereinafter referred to as a load measurement value) L is input. The stop determination units 11, 12, and 13 determine that other power supply units have stopped operating based on the input unit measurement values and load measurement values, and stop determination signals S _B1 , S _B2 , and S _B3. Is transmitted to the upper control / monitoring unit 30.

The control / monitoring unit 30 can transmit operation commands (start command or stop command) S _A1 , S _A2 , S _A3 to the power supply units PSU1, PSU2, PSU3, and stop determination signals S _B1 , S _B2 , S _B3. It has a function to output an alarm based on.

  In this embodiment, the unit output measuring units 21, 22, and 23 and the load measuring unit 20 measure power. However, the current may be measured and used for determination processing in the stop determination units 11, 12, and 13. .

Next, the operation of this embodiment will be described.
FIG. 2 is a flowchart showing operations of the stop determination units 11, 12, 13 and the control / monitoring unit 30 of the power supply units PSU1, PSU2, and PSU3. In the following description, the two power supply units PSU1 and PSU2 are operated and share the load power equally, and the remaining power supply unit PSU3 is originally stopped by a stop command from the control / monitoring unit 30. Suppose you are.
Here, based on FIG. 2, the operation of the stop determination unit 11 of the power supply unit PSU1 will be described together with the operation of the control / monitoring unit 30, but the operation of the stop determination unit 12 of the other power supply unit PSU2 is also the same.

2, the stop determination unit 11 of the power supply unit PSU1, first, the time t and the last time (t-1) in a ratio of change in the ratio between load measures L of the change in own unit measurements P ₁ respectively Calculate (step S1).
Here, the time t and the past time (t−1) are times separated by one sampling period, and the ratio of the change of the unit measurement value P ₁ described above is P _t / P _t−1 and the load measurement value. The ratio of change in L is expressed as L _t / L _t-1 .
When the unit output measuring units 21, 22, 23 and the load measuring unit 20 measure currents, the stop determination unit 11 measures the output current of its own unit at time t and past time (t-1). The ratio of change in value and the ratio of change in load current measurement are calculated respectively.

Next, the stop determination unit 11 calculates a deviation ε of the ratio of each measurement value using the following formula (step S2).
ε = (P _t / P _t−1 ) − (L _t / L _t−1 )
Further, it is determined whether or not the absolute value | ε | of the deviation ε exceeds a predetermined threshold value ε _u (step S3). Depending on the determination result of step S3, the stop determination unit 11 determines whether the other power supply unit PSU2 is stopped or is operating normally.

  In the following, the determination operation of the stop determination unit 11 according to the fluctuation of the unit measurement value and the load measurement value will be described with reference to FIG. 2 described above and FIG. 3 showing various fluctuation patterns of the unit measurement value and the load measurement value. explain.

この場合には、他の電源ユニットＰＳＵ２は正常に運転されていると判定し、次のサンプリング時刻まで処理をホールドし、現時点の処理を終了する（ステップＳ３ＮＯ）。 FIG. 3A shows a case where the unit measurement value P (P ₁ ) and the load measurement value L are hardly changed from the past time (t−1) to the time t as in Expression 1.

In this case, it is determined that the other power supply unit PSU2 is operating normally, the process is held until the next sampling time, and the current process is terminated (NO in step S3).

この場合には、負荷測定値Ｌの増加比率と自己のユニット測定値Ｐの増加比率との間に余り差がないため、他の電源ユニットＰＳＵ２は正常に運転されていると判定し、次のサンプリング時刻まで処理をホールドし、現時点の処理を終了する（ステップＳ３ＮＯ）。 FIG. 3 (2) shows that the unit measurement value P and the load measurement value L are both increasing from the past time (t-1) to the time t, as shown in Equation 2, but the deviation ε the absolute value | ε | is if it does not exceed the threshold ε _u.

In this case, since there is not much difference between the increase rate of the load measurement value L and the increase rate of its own unit measurement value P, it is determined that the other power supply unit PSU2 is operating normally, and the next The process is held until the sampling time, and the current process is terminated (NO in step S3).

この場合、他の電源ユニットＰＳＵ２が停止した結果、それまで電源ユニットＰＳＵ２が分担していた出力を自己（電源ユニットＰＳＵ１）が補うために自己のユニット測定値Ｐが増加したと考えられる。よって、停止判定部１１は、電源ユニットＰＳＵ２が停止していると判定し、制御・監視部３０に停止判定信号Ｓ_Ｂ１を送信する（ステップＳ４）。 FIG. 3 (3) shows that the unit measurement value P increases while the load measurement value L hardly changes between the past time (t-1) and the time t, as shown in Equation 3. and has an absolute value of the deviation epsilon | epsilon | is if exceeds the threshold epsilon _u (step S3YES).

In this case, as a result of the other power supply unit PSU2 being stopped, it is considered that the self unit measurement value P has increased because the self (power supply unit PSU1) supplements the output shared by the power supply unit PSU2 until then. Therefore, the stop determination unit 11 determines that the power supply unit PSU2 is stopped, it sends a stop determination signal _{S B1} to the control and monitoring unit 30 (step S4).

この場合は、図３（２）に比べて、自己のユニット測定値Ｐの増加比率が大きくなった結果、偏差εの絶対値｜ε｜がしきい値ε_ｕを超えており、他の電源ユニットＰＳＵ２が停止したためにその分担出力を自己（電源ユニットＰＳＵ１）が補っていると考えられる。従って、停止判定部１１は、電源ユニットＰＳＵ２が停止していると判定し、制御・監視部３０に停止判定信号Ｓ_Ｂ１を送信する（ステップＳ４）。 In FIG. 3 (4), as shown in Equation 4, both the unit measurement value P and the load measurement value L increase from the past time (t-1) to the time t, and the absolute value | ε | a case where exceeds the threshold epsilon _u (step S3YES).

In this case, the absolute value | ε | of the deviation ε exceeds the threshold value ε _u as a result of the increase rate of its own unit measurement value P being larger than that in FIG. Since the unit PSU2 is stopped, it is considered that the self (power supply unit PSU1) supplements the shared output. Therefore, the stop determination unit 11 determines that the power supply unit PSU2 is stopped, it sends a stop determination signal _{S B1} to the control and monitoring unit 30 (step S4).

この場合には、負荷測定値Ｌの減少比率と自己のユニット測定値Ｐの減少比率との間に余り差がないため、他の電源ユニットＰＳＵ２は正常に運転されていると判定し、次のサンプリング時刻まで処理をホールドし、現時点の処理を終了する（ステップＳ３ＮＯ）。 FIG. 3 (5) shows that the unit measurement value P and the load measurement value L are both decreased from the past time (t-1) to the time t as shown in Equation 5, but the deviation ε the absolute value | ε | is if it does not exceed the threshold ε _u.

In this case, since there is not much difference between the reduction ratio of the load measurement value L and the reduction ratio of the own unit measurement value P, it is determined that the other power supply unit PSU2 is operating normally. The process is held until the sampling time, and the current process is terminated (NO in step S3).

この場合は、時刻ｔと過去時刻（ｔ−１）との間で他の電源ユニット、例えば電源ユニットＰＳＵ３が制御・監視部３０からの起動指令によって起動された結果、自己（電源ユニットＰＳＵ１）の分担出力が減少したと考えられるため、電源ユニットＰＳＵ２は正常に運転されていると判断することができる。
但し、絶対値｜ε｜がしきい値ε_ｕを超えているため、ステップＳ３の判断結果はＹＥＳとなり、停止判定部１１は停止判定信号Ｓ_Ｂ１を制御・監視部３０に送信する（ステップＳ４）。しかし、時刻ｔ以前には、他の電源ユニットＰＳＵ３に対して停止指令が送られていたはずであるから、図２における後述のステップＳ５の判断はＮＯとなり、結果的に、電源ユニットＰＳＵ２は停止しておらず正常に運転されていると判定される。 In FIG. 3 (6), as shown in Equation 6, the load measurement value L hardly changes between the past time (t-1) and the time t, whereas the own unit measurement value P decreases. and has an absolute value of the deviation epsilon | epsilon | is if exceeds the threshold epsilon _u (step S3YES).

In this case, as a result of activation of another power supply unit, for example, power supply unit PSU3 by the activation command from the control / monitoring unit 30 between time t and past time (t−1), the self (power supply unit PSU1) Since the shared output is considered to have decreased, it can be determined that the power supply unit PSU2 is operating normally.
However, the absolute value | epsilon | because exceeds the threshold epsilon _u, the determination result is YES in step S3, the stop determination unit 11 sends a stop determination signal _{S B1} to the control and monitoring unit 30 (step S4 ). However, since a stop command should have been sent to the other power supply unit PSU3 before time t, the determination in step S5 described later in FIG. 2 is NO, and as a result, the power supply unit PSU2 is stopped. It is determined that the vehicle is operating normally.

この場合は、図３（５）と比べると、負荷測定値Ｌの減少比率に対して自己のユニット測定値Ｐの減少比率が小さくなっており、他の電源ユニットＰＳＵ２が停止したことにより自己のユニット測定値Ｐの減少（分担出力の減少）が抑制されたと考えられる。
従って、停止判定部１１は、他の電源ユニットＰＳＵ２が停止していると判定し、制御・監視部３０に停止判定信号Ｓ_Ｂ１を送信する（ステップＳ４）。 FIG. 3 (7) shows that the unit measurement value P and the load measurement value L both decrease from the past time (t-1) to the time t, and the absolute value of the deviation ε, as shown in Equation 7. | epsilon | is if exceeds the threshold epsilon _u (step S3YES).

In this case, as compared with FIG. 3 (5), the reduction ratio of the own unit measurement value P is smaller than the reduction ratio of the load measurement value L, and the other power supply unit PSU2 is stopped. It is thought that the decrease in unit measurement value P (reduction in shared output) was suppressed.
Therefore, the stop determination unit 11 determines that the other power supply unit PSU2 is stopped, sends a stop determination signal _{S B1} to the control and monitoring unit 30 (step S4).

この場合は、他の電源ユニットＰＳＵ２が停止した結果、電源ユニットＰＳＵ２がそれまで分担していた出力を自己（電源ユニットＰＳＵ１）が補うために自己のユニット測定値Ｐが増加したと考えられる。よって、停止判定部１１は、電源ユニットＰＳＵ２が停止していると判定し、制御・監視部３０に停止判定信号Ｓ_Ｂ１を送信する（ステップＳ４）。 In FIG. 3 (8), as shown in Equation 8, the load measurement value L decreases while the unit measurement value P increases while the load measurement value L decreases from the past time (t-1) to the time t. , the absolute value | epsilon | is if exceeds the threshold epsilon _u (step S3YES).

In this case, as a result of the other power supply unit PSU2 being stopped, it is considered that the self unit measurement value P has increased because the self (power supply unit PSU1) supplements the output shared by the power supply unit PSU2 so far. Therefore, the stop determination unit 11 determines that the power supply unit PSU2 is stopped, it sends a stop determination signal _{S B1} to the control and monitoring unit 30 (step S4).

In the flowchart of FIG. 2, the control / monitoring unit 30 does not transmit a stop command to the other power supply unit PSU2 at the time t, but the case of FIG. 3 (6) described above from the power supply unit PSU1. When the stop determination signal S _B1 is received (step S5 YES), it is determined that the stop determination signal S _B1 is due to a stop due to the failure of the power supply unit PSU2 (step S6).
That is, various fluctuation patterns as shown in FIG. 3 can also occur during normal start / stop, but despite the fact that no stop command is transmitted to any of the power supply units, FIG. (4), when the variation pattern of ...... etc. receives a stop determination signal S _B1 from the power supply unit PSU1 occurred is to detect that the power supply PSU2 stops because of a breakdown.

Control and monitoring unit 30, upon detecting a stop due to a failure of the power supply unit PSU2 by the stop determination signal _{S B1,} the power supply unit in the other stop conditions, for example, the power supply unit PSU3 generates a start command _{S A3} with respect to the power supply unit PSU3 In addition to the transmission, processing such as generating an alarm for reporting a failure of the power supply unit PSU2 is executed (step S6).

  If the control / monitoring unit 30 receives a stop determination signal from any power supply unit even though it has not transmitted a stop command at time t, all the healthy power supply units that were originally stopped It is desirable to activate them by sending activation commands to Further, when all the healthy power supply units are already operating, a spare power supply unit may be further activated.

  As described above, according to the present embodiment, even when a certain power supply unit is stopped due to a failure, the control / monitoring unit 30 can detect an abnormality based on a stop determination signal from another healthy power supply unit. Then, a process such as starting a sound power supply unit and performing a backup operation can be taken. Thereby, there is no possibility that the sound power supply unit in operation is overloaded, and the safe and continuous operation of the power supply system can be maintained. It is also possible to output an alarm from the control / monitoring unit 30 to prompt the user to perform maintenance / inspection work.

  Next, FIG. 4 is a diagram illustrating unit measurement values, load measurement values, and the like when the number of operating units decreases due to a certain power supply unit being stopped. In FIG. 4, N is the total number of power supply units included in the power supply system, and is a natural number of 2 or more.

With the N power supply units equally sharing the load power, one power supply unit stops between time (t−1) and time t, and at time t, N-1) It is assumed that the number has decreased. In this case, the unit measurement value P and the load measurement value L at times (t−1) and t can be expressed as functions of the load measurement values L _t−1 , L _t and the total number N, respectively. The deviation ε between the change ratio (P _t / P _t-1 ) and the change ratio (L _t / L _t-1 ) of the load measurement value L is (L _t / L _t-1 ) · {1 / ( N−1)}, the threshold value ε _u used for the stop determination of the above-described equations 1 to 8 may be set according to equation 9.
[Formula 9]
ε _u = (L _t / L _t−1 ) · {1 / (N−1)}

  The present invention can be used as a power supply system in which a plurality of switching power supplies are connected in parallel or a power supply system constituting a DC power supply unit of an uninterruptible power supply.

11, 12, 13: Stop determination unit 20: Load measurement units 21, 22, 23: Unit output measurement unit 30: Control / monitoring unit 41: Three-phase power system 42: Transformer 50: Load PS: Power supply systems PSU1, PSU2 , PSU3: Power supply unit

Claims (7)

A power supply system that supplies power to a load by a plurality of power supply units connected in parallel to each other, and includes a control / monitoring unit capable of transmitting a start / stop command to each power supply unit.
The power supply units each include a stop determination unit that determines stop of other power supply units in the power supply system,
The stop determination unit
Using the unit measurement value obtained by measuring the output of its own power supply unit and the load measurement value obtained by measuring the power supplied to the load by the plurality of power supply units, the unit measurement value changed within a predetermined time. A deviation between the ratio and the ratio of the load measurement value is calculated, and when the deviation exceeds a predetermined threshold, it is determined that the other power supply unit is stopped, and the stop determination signal is A power supply system that transmits to a monitoring unit. In the power supply system according to claim 1,
The control / monitoring unit that has received the stop determination signal despite not transmitting a stop command to the other power supply unit transmits a start command to a startable power supply unit in the power supply system. A power supply system characterized by In the power supply system according to claim 2,
The control / monitoring unit that has received the stop determination signal transmits a start command to all the power supply units except the other power supply units. The power supply system according to claim 2 or 3,
The control / monitoring unit that has received the stop determination signal detects that the other power supply unit is stopped due to a failure and generates an alarm. In the power supply system described in any one of Claims 1-4,
The power supply system, wherein the threshold value is set based on a ratio of the load measurement values changed within the predetermined time and the total number of power supply units in the power supply system. In the power supply system described in any one of Claims 1-5,
The power supply system, wherein the unit measurement value and the load measurement value are electric power or current. In the power supply system described in any one of Claims 1-6,
The power supply system, wherein the power supply unit is a power converter that performs AC / DC conversion.

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