JP7775701B2 - Power supply control device and power supply control method - Google Patents

Description

The present invention relates to a power supply control device and a power supply control method.

The power source that supplies power and the power receiving devices that operate by receiving power from the power source are connected using cables and power distributors (hereinafter referred to as power supply cables, etc.) selected based on the current consumption of each power receiving device, etc. (See, for example, Patent Documents 1-3).

Japanese Patent Application Laid-Open No. 2020-36400 JP 2017-92916 A JP 2018-41170 A

Power supply cables and other devices are selected based on the current and voltage between the power source and the power receiving device. However, if this selection is incorrect, there is a risk that the power source will supply dangerous power in places where the allowable current or voltage of the power supply cable or other device is exceeded.

One aspect of the disclosed technology aims to provide a power supply control device and a power supply control method that can suppress dangerous power supply.

One aspect of the disclosed technology is exemplified by the following power supply control device. The power supply control device controls power supply from a power source in a system including a power source, a power receiving device that operates by receiving power from the power source, and a power supply cable connecting the power source and the power receiving device. The power supply control device includes an acquisition unit that acquires location information for the power supply cable and the power receiving device in the system and acquires characteristic information related to the power of the power supply cable and the power receiving device, a determination unit that determines whether power supply is possible based on the location information and the characteristic information, and a control unit that prohibits the start of power supply from the power source if the determination by the determination unit is negative.

The power supply control device can determine whether or not power can be supplied based on the arrangement information of the power supply cable and power receiving device in the system and characteristic information related to power. The determination unit makes a negative determination, for example, if the current consumption or power consumption of the power receiving device is greater than the allowable current or allowable power of the connection cable connected upstream (to the power source) of the power receiving device. If the determination is negative, the control unit prohibits power supply from the power source. This allows the power supply control device to prevent dangerous power supply.

In the power supply control device, the characteristic information may include information indicating the allowable current of the power supply cable and information indicating the current consumption of the power receiving device, and the determination unit may make a negative determination if the allowable current of the power supply cable connected closer to the power source than the power receiving device is lower than the current consumption of the power receiving device.

In the power supply device, the acquiring unit may acquire the arrangement information and the characteristic information through power line communication using the power supply cable. By adopting such a configuration, it is not necessary to prepare a communication cable in addition to the power supply cable, and therefore the configuration can be simplified.

The acquisition unit may then acquire the placement information and the characteristic information by supplying a predetermined current to the power source for performing the power line communication. Because the predetermined current for performing the power line communication is smaller than the current used for operating the power receiving device, the acquisition unit can more safely acquire the placement information and the characteristic information.

In the power supply control device, the characteristic information includes information indicating the allowable current of the power supply cable and information indicating the current consumption of the power receiving device, and the control unit may limit the current supplied by the power source to less than the allowable current when the current consumption exceeds the allowable current of the power supply cable connected to the power source side of the power receiving device. By incorporating such a feature, the power supply control device is able to drive the power receiving device even when a power receiving device with a current exceeding the allowable current is connected.

In the power supply control device, the characteristic information may include information indicating the allowable current of the power supply cable, and the acquisition unit may monitor the supply current supplied from the power source to the power receiving device while the power receiving device is operating on power from the power source, and the control unit may stop power supply from the power source if the supply current exceeds the allowable current of the power supply cable connected to the power source side of the power receiving device. The supply current supplied to the power receiving device may fluctuate depending on the operation of the power receiving device. This fluctuation may cause the supply current to exceed the allowable current of the power supply cable. By incorporating these features, the power supply control device can prevent dangerous power supply even while the power receiving device is operating.

In the power supply device, the control unit may continue to acquire the location information of the power supply cable and the power receiving device while the power receiving device is being driven by receiving power from the power source, and the control unit may stop power supply from the power source if the acquisition unit does not acquire the location information of at least one of the power supply cable and the power receiving device. By incorporating this feature, the power supply control device can stop power supply if a connection failure, such as a poor connection between the power supply cable or the power receiving device, occurs while the power receiving device is being driven.

In the power supply device, the control unit may notify the power receiving device that power supply will be stopped before causing the power source to stop supplying power. By incorporating this feature, the power supply control device can prompt the power receiving device to perform a shutdown process before power supply is stopped.

The disclosed technology can also be understood from the perspective of a power supply control method.

The disclosed technology can prevent dangerous power supply.

FIG. 1 is a diagram illustrating an example of a servo system according to an embodiment. FIG. 2 is a diagram illustrating the configuration of an information unit. FIG. 3 is a diagram illustrating an example of a hardware configuration of a power supply control device. FIG. 4 is a diagram illustrating an example of a processing block of an information unit. FIG. 5 is a diagram illustrating an example of a processing block of the power supply control device. FIG. 6 is a diagram illustrating a process of acquiring characteristic information and arrangement information related to the power of each unit by the acquiring unit. FIG. 7 is a diagram illustrating an example of a processing flow of the DC power supply unit according to the embodiment. FIG. 8 is a diagram illustrating an example of a processing block of the power supply control device in the first modified example. FIG. 9 is a diagram showing an example of a processing flow of the DC power supply unit in the first modified example.

<Embodiment>
A servo system according to an embodiment will be described below with reference to the drawings. Fig. 1 shows an example of a servo system 100 according to an embodiment. The servo system 100 includes an AC power supply 1, a breaker 2, a DC power supply unit 3, a power distributor 4, a functional unit 5, a servo driver 6, and a power supply line 7.

In the servo system 100, the AC power supply 1, breaker 2, DC power supply unit 3, and power distributor 4 are connected in this order from the upstream side (AC power supply 1 side). The AC power supply 1 and breaker 2, and the breaker 2 and DC power supply unit 3 are connected by a second power feed line 8. The DC power supply unit 3 and the power distributor 4, located downstream of the DC power supply unit 3, are connected by a first power feed line 7a. The functional unit 5a is connected downstream of the power distributor 4 by a first power feed line 7b, and the functional unit 5b is connected by a first power feed line 7c. The servo driver 6a is connected downstream of the functional unit 5a by a first power feed line 7d. The servo driver 6b is connected downstream of the servo driver 6a by a first power feed line 7e.

The DC power supply unit 3 converts AC power supplied from the AC power supply 1 into DC power and supplies it to the servo drivers 6a and 6b. A breaker 2 is provided between the DC power supply unit 3 and the AC power supply 1, preventing AC power above a predetermined voltage from being supplied from the AC power supply 1 to the DC power supply unit 3. The DC power supply unit 3 is also provided with a power supply control device 31. The DC power supply unit 3 is an example of a "power supply."

The power supply control device 31 obtains the allowable current and voltage allowed by the power distributor 4, functional units 5a, 5b, servo drivers 6a, 6b, and first power supply lines 7a, 7b, 7c, 7d, and 7e connected downstream of the DC power supply unit 3, as well as the current consumption of the servo drivers 6a and 6b, and determines the suitability of the configuration. Hereinafter, the functional units 5a and 5b will be collectively referred to as functional units 5. The servo drivers 6a and 6b will be collectively referred to as servo drivers 6. The first power supply lines 7a, 7b, 7c, 7d, and 7e will be collectively referred to as first power supply lines 7.

The DC power converted by the DC power supply unit 3 is supplied to the power distributor 4 via the first power supply line 7a. The power distributor 4 distributes the DC power from the DC power supply unit 3 to each of the two sets of function units 5 and servo drivers 6. The power distributor 4 is equipped with an information unit 9.

The functional unit 5 is a unit that packages a breaker 51 and a noise filter 52. DC power distributed from the power distributor 4 is supplied to the servo driver 6 via the functional unit 5. The breaker 51 is placed between the power distributor 4 and the servo driver 6 to protect the servo driver 6 from overload. In addition, the noise filter 52 is placed between the power distributor 4 and the servo driver 6 to remove noise from the DC power supplied to the servo driver 6. The functional unit 5 is provided with an information unit 9.

The servo driver 6 operates by receiving power from the DC power supply unit 3. The servo driver 6 receives a feedback signal from a servo motor (not shown). The servo driver 6 is formed with a servo system that performs feedback control using a position controller, a speed controller, a current controller, etc., and these signals are used to servo-control and drive the servo motor. The servo driver 6 is provided with an information unit 9. The servo driver 6 is an example of a "power receiving device."

The first power feed line 7 and the second power feed line 8 are power feed lines that transmit power. The first power feed line 7 is also used as a communication cable that utilizes Power Line Communication (PLC). The first power feed line 7 is provided with an information unit 9. The information unit 9 provided on the first power feed line 7 may be disposed, for example, within the connector connecting the first power feed line 7. The information unit 9 provided on the first power feed line 7 may also be disposed on the cable of the first power feed line 7. The first power feed line 7 is an example of a "power feed cable."

Figure 2 is a diagram illustrating the configuration of the information unit 9. The information unit 9 includes a central processing unit (CPU) 91, a memory unit 92, and a signal processing unit 93. The CPU 91, memory unit 92, and signal processing unit 93 are interconnected by a connection bus B1.

The CPU 91 is also called a microprocessor unit (MPU) or processor. The CPU 91 is not limited to a single processor and may have a multi-processor configuration. Furthermore, a single CPU 91 connected via a single socket may have a multi-core configuration. In the information unit 9, the CPU 91 controls peripheral devices by executing programs stored in the memory unit 92. This allows the information unit 9 to execute processing that meets a specified purpose. The memory unit 92 is a recording medium that can be read by the CPU 91.

The memory unit 92 is exemplified as a memory unit accessed by the CPU 91. Examples of the memory unit 92 include Random Access Memory (RAM), Read Only Memory (ROM), and Erasable Programmable ROM (EPROM). The memory unit 92 stores, for example, the allowable current, allowable voltage, and current consumption allowed by the device itself. For example, the information unit 9 provided in the first power supply line 7 stores the allowable current and allowable voltage of the first power supply line 7 in the memory unit 92. Furthermore, for example, the information unit 9 provided in the servo driver 6 stores the allowable current, allowable voltage, and current consumption of the servo driver 6 in the memory unit 92.

The signal processing unit 93 is an interface used for power line communication via the first power feed line 7. The signal processing unit 93 communicates with other units, for example, using power line communication via the first power feed line 7.

Figure 3 shows an example of the hardware configuration of the power supply control device 31. Like the information unit 9, the power supply control device 31 includes a CPU 91, a memory unit 92, and a signal processing unit 93. The memory unit 92 of the power supply control device 31 stores a computer program that acquires the allowable current and allowable voltage of each unit and the current consumption of each unit, as well as acquires the layout information of each unit in the servo system 100, and causes the power supply control device 31 to determine whether the configuration is appropriate.

Figure 4 is a diagram showing an example of the processing blocks of the information unit 9. The information unit 9 includes a search unit 911, an inquiry unit 912, and a notification unit 913. The information unit 9 executes the processing of each of the components of the information unit 9, such as the search unit 911, inquiry unit 912, and notification unit 913, by the CPU 91 executing a computer program stored in the memory unit 92.

The search unit 911 searches for other units connected downstream of the unit in which the information unit 9 is installed. The search by the search unit 911 is performed, for example, by power line communication via the signal processing unit 93.

The inquiry unit 912 inquires about the current consumption, allowable current, and allowable voltage of other units found by the search unit 911. The inquiry by the inquiry unit 912 is made, for example, via power line communication via the signal processing unit 93.

The notification unit 913 notifies other units connected upstream of the unit in which the information unit 9 is installed of the current consumption, allowable current, and allowable voltage of the unit in which the information unit 9 is installed. When the notification unit 913 receives a notification from another unit connected downstream of the unit in which the information unit 9 is installed, it also notifies the other units connected upstream of the unit in which the information unit 9 is installed of the information contained in the received notification. Notification by the information unit 9 is performed, for example, by power line communication via the signal processing unit 93.

Figure 5 is a diagram showing an example of the processing blocks of the power supply control device 31. The power supply control device 31 includes an acquisition unit 311, a determination unit 312, and a control unit 313. The power supply control device 31 executes the processes of each unit of the power supply control device 31, such as the acquisition unit 311, determination unit 312, and control unit 313, by the CPU 91 executing a computer program stored in the storage unit 92.

The acquisition unit 311 acquires the location information of each unit in the servo system 100, namely, the power distributor 4, the functional unit 5, the servo driver 6, and the first power feed line 7. The location information is, for example, information indicating the relative positional relationship of each unit in the servo system 100. From the location information, it is possible to understand, for example, that power feed cable 7b is connected to the upstream side (power supply side) of functional unit 5a, and that power feed cable 7d is connected to the downstream side of functional unit 5a. The acquisition unit 311 also acquires power-related characteristic information, such as the allowable current, allowable voltage, and current consumption of each unit. The location information and characteristic information are acquired, for example, via power line communication. For example, the acquisition unit 311 queries the information units 9 provided in each of the power distributor 4, the functional unit 5, the servo driver 6, and the first power feed line 7 via power line communication via the first power feed line 7, and acquires this information. The acquisition unit 311 also monitors and acquires the supply current supplied to the servo driver 6 while the servo driver 6 is being driven by power supplied from the DC power supply unit 3.

The acquisition unit 311 stores the acquired placement information and characteristic information for each unit in the storage unit 92 of the power supply control device 31. At this time, the acquisition unit 311 may store the characteristic information in the storage unit 92 of the power supply control device 31 using, for example, a tree-structured data structure with the DC power supply unit 3 as the root, so that the placement of each unit in the servo system 100 can be determined.

Based on the information acquired by the acquisition unit 311, the determination unit 312 determines whether the power distributor 4, functional unit 5, servo driver 6, and first power feed line 7 are configured to perform dangerous power feeding. For example, the determination unit 312 determines that the configuration is performing dangerous power feeding when the sum of the current consumptions of servo drivers 6a and 6b connected downstream of the power distributor 4 is greater than the allowable power of the power distributor 4. In other words, the determination unit 312 determines that the configuration is performing dangerous power feeding when the sum of the current consumptions of devices connected downstream of a certain unit exceeds the allowable current of that unit. The determination unit 312 may also determine that the configuration is performing dangerous power feeding when the current supplied by the DC power supply unit 3 is greater than the allowable current of the first power feed line 7a connected downstream of the DC power supply unit 3.

The judgment unit 312 may also judge that a dangerous power supply is occurring when the supply current supplied to the servo driver 6 during operation exceeds the allowable current of at least one of the power distributor 4, functional unit 5, and first power supply line 7 located upstream of the servo driver 6.

If the determination unit 312 determines that the configuration is one in which dangerous power supply will occur, the control unit 313 stops power supply from the DC power supply unit 3 and issues a warning. Furthermore, if the determination unit 312 does not determine that the configuration is one in which dangerous power supply will occur, the control unit 313 causes the DC power supply unit 3 to start supplying power to each unit connected downstream of the DC power supply unit 3.

Figure 6 is a diagram that schematically illustrates the process by which the acquisition unit 311 acquires characteristic information and placement information related to the power of each unit. In Figure 6, arrows are used to schematically illustrate inquiries from the DC power supply unit 3 to each of the following units: the first power feeder 7a, the power distributor 4, the first power feeder 7b, the functional unit 5a, the first power feeder 7d, the servo driver 6a, the first power feeder 7c, the functional unit 5b, the first power feeder 7e, and the servo driver 6b, and notifications from each unit.

First, the DC power supply unit 3 supplies a communication current sufficient to enable power line communication. The communication current may be a current that is insufficient for the servo driver 6 to drive the motor, as long as it is sufficient to receive notifications from the power distributor 4, functional unit 5, servo driver 6, and first power feed line 7 using power line communication. In other words, the communication current may be a predetermined current sufficient to receive notifications from the power distributor 4, functional unit 5, servo driver 6, and first power feed line 7 using power line communication. When the supply of communication current begins, the acquisition unit 311 of the DC power supply unit 3 queries the first power feed line 7a (T1).

When the first power feeder 7a receives an inquiry from the DC power supply unit 3, the search unit 911 of the information unit 9 provided on the first power feeder 7a searches for other units connected downstream and detects the power distributor 4. The inquiry unit 912 of the information unit 9 provided on the first power feeder 7a then makes an inquiry to the power distributor 4 detected by the search unit 911 (T2).

When the distributor 4 receives an inquiry from the first power feeder 7a, the search unit 911 of the information unit 9 provided in the distributor 4 searches for other units connected downstream of the distributor 4 and detects the first power feeder 7b and the first power feeder 7c. The inquiry unit 912 of the information unit 9 provided in the distributor 4 makes an inquiry (T3) about the first power feeder 7b detected by the search unit 911 and an inquiry (T7) about the first power feeder 7c.

When the first power feeder 7b receives an inquiry from the power distributor 4, the search unit 911 of the information unit 9 provided on the first power feeder 7b searches for other units connected downstream of the first power feeder 7b and detects the functional unit 5a. The inquiry unit 912 of the information unit 9 provided on the first power feeder 7b then makes an inquiry to the functional unit 5a detected by the search unit 911 (T4).

In functional unit 5a, which receives the inquiry from first power supply line 7b, the search unit 911 of the information unit 9 provided in functional unit 5a searches for other units connected downstream of functional unit 5a and detects first power supply line 7d. The inquiry unit 912 of the information unit 9 provided in functional unit 5a then makes an inquiry to the first power supply line 7d detected by the search unit 911 (T5).

In the first power supply line 7d that has received the inquiry from the functional unit 5a, the search unit 911 of the information unit 9 provided on the first power supply line 7d searches for other units connected downstream of the first power supply line 7d and detects the servo driver 6a. The inquiry unit 912 of the information unit 9 provided on the first power supply line 7d makes an inquiry to the servo driver 6a detected by the search unit 911 (T6).

Furthermore, on the first power feeder 7c that has received an inquiry from the power distributor 4, the search unit 911 of the information unit 9 provided on the first power feeder 7c searches for other units connected downstream of the first power feeder 7c and detects the functional unit 5b. The inquiry unit 912 of the information unit 9 provided on the first power feeder 7c then makes an inquiry to the functional unit 5b detected by the search unit 911 (T8).

In functional unit 5b, which receives the inquiry from the first power supply line 7c, the search unit 911 of the information unit 9 provided in functional unit 5b searches for other units connected downstream of functional unit 5b and detects the first power supply line 7e. The inquiry unit 912 of the information unit 9 provided in functional unit 5b then makes an inquiry to the first power supply line 7e detected by the search unit 911 (T9).

When the first power supply line 7e receives an inquiry from the functional unit 5b, the search unit 911 of the information unit 9 provided on the first power supply line 7e searches for other units connected downstream of the first power supply line 7e and detects the servo driver 6b. The inquiry unit 912 of the information unit 9 provided on the first power supply line 7e then makes an inquiry to the servo driver 6b detected by the search unit 911 (T10).

When the servo driver 6a receives an inquiry from the first power supply line 7d, the search unit 911 of the information unit 9 provided in the servo driver 6a searches for other units connected downstream of the servo driver 6a and recognizes that the servo driver 6a is the final stage of the power line communication network. Having recognized that it is the final stage, the notification unit 913 of the information unit 9 provided in the servo driver 6a notifies the first power supply line 7d of the allowable current, allowable voltage, and current consumption of the servo driver 6a. Furthermore, the notification unit 913 of the information unit 9 provided in the servo driver 6a notifies the first power supply line 7d that the servo driver 6a is the final stage (T11).

When the first power supply line 7d receives the notification from the servo driver 6a, the notification unit 913 of the information unit 9 provided on the first power supply line 7d notifies the functional unit 5a of the allowable current and allowable voltage of the first power supply line 7d, as well as the allowable current, allowable voltage, and current consumption of the servo driver 6a received from the servo driver 6a. Furthermore, the notification unit 913 of the information unit 9 provided on the first power supply line 7d notifies the functional unit 5a that the servo driver 6a is connected downstream of the first power supply line 7d and that the servo driver 6a is the final stage (T12).

In functional unit 5a, which has received the notification from the first power supply line 7d, the notification unit 913 of the information unit 9 provided in functional unit 5a notifies the first power supply line 7b of the allowable current and allowable voltage of functional unit 5a, the allowable current and allowable voltage of first power supply line 7d received from the first power supply line 7d, and the allowable current, allowable voltage, and current consumption of servo driver 6a. Furthermore, the notification unit 913 of the information unit 9 provided in functional unit 5a notifies the first power supply line 7b that the first power supply line 7d is connected downstream of functional unit 5a, that the servo driver 6a is connected downstream of the first power supply line 7d, and that the servo driver 6a is the final stage (T13).

In the first power feeder 7b that has received the notification from the functional unit 5a, the notification unit 913 of the information unit 9 provided on the first power feeder 7b notifies the distributor 4 of the allowable current and allowable voltage of the first power feeder 7b, the allowable current and allowable voltage of the first power feeder 7d received from the functional unit 5a, the allowable current, allowable voltage, and current consumption of the servo driver 6a, and the allowable current and allowable voltage of the functional unit 5a. Furthermore, the notification unit 913 of the information unit 9 provided on the first power feeder 7b notifies the distributor 4 that the functional unit 5a is connected downstream of the first power feeder 7b, that the first power feeder 7d is connected downstream of the functional unit 5a, that the servo driver 6a is connected downstream of the first power feeder 7d, and that the servo driver 6a is the final stage (T14).

Furthermore, in the servo driver 6b that received the inquiry from the first power supply line 7e, the search unit 911 of the information unit 9 provided in the servo driver 6b searches for other units connected downstream of the servo driver 6b and recognizes that the servo driver 6b is the final stage of the power line communication network. Having recognized that it is the final stage, the notification unit 913 of the information unit 9 provided in the servo driver 6b notifies the first power supply line 7e of the allowable current, allowable voltage, and current consumption of the servo driver 6b. Furthermore, the notification unit 913 of the information unit 9 provided in the servo driver 6b notifies the first power supply line 7e that the servo driver 6b is the final stage (T15).

On the first power supply line 7e, which has received the notification from the servo driver 6b, the notification unit 913 of the information unit 9 provided on the first power supply line 7e notifies the functional unit 5b of the allowable current and allowable voltage of the first power supply line 7e, as well as the allowable current, allowable voltage, and current consumption of the servo driver 6a received from the servo driver 6b. Furthermore, the notification unit 913 of the information unit 9 provided on the first power supply line 7e notifies the functional unit 5b that the servo driver 6b is connected downstream of the first power supply line 7e and that the servo driver 6b is the final stage (T16).

In functional unit 5b, which has received the notification from the first power supply line 7e, the notification unit 913 of the information unit 9 provided in functional unit 5b notifies the first power supply line 7c of the allowable current and allowable voltage of functional unit 5b, the allowable current and allowable voltage of first power supply line 7e received from the first power supply line 7e, and the allowable current, allowable voltage, and current consumption of servo driver 6b. Furthermore, the notification unit 913 of the information unit 9 provided in functional unit 5b notifies the first power supply line 7c that the first power supply line 7e is connected downstream of functional unit 5b, that the servo driver 6b is connected downstream of the first power supply line 7e, and that the servo driver 6b is the final stage (T17).

On the first power feeder 7c, which has received the notification from functional unit 5b, the notification unit 913 of the information unit 9 provided on the first power feeder 7c notifies the distributor 4 of the allowable current and allowable voltage of the first power feeder 7c, the allowable current and allowable voltage of the first power feeder 7e received from functional unit 5b, the allowable current, allowable voltage, and current consumption of the servo driver 6b, and the allowable current and allowable voltage of the functional unit 5b. Furthermore, the notification unit 913 of the information unit 9 provided on the first power feeder 7c notifies the distributor 4 that the functional unit 5b is connected downstream of the first power feeder 7c, that the first power feeder 7e is connected downstream of the functional unit 5b, that the servo driver 6b is connected downstream of the first power feeder 7e, and that the servo driver 6b is the final stage (T18).

In the distributor 4 that has received the notifications from the first power feeder 7b and the first power feeder 7c, the notification section 913 of the information unit 9 provided in the distributor 4 notifies the first power feeder 7a of the allowable current and allowable voltage of the distributor 4, the allowable current and allowable voltage of the first power feeder 7b received from the first power feeder 7b, the allowable current and allowable voltage of the first power feeder 7d, the allowable current, allowable voltage, and current consumption of the servo driver 6a, the allowable current and allowable voltage of the functional unit 5a, the allowable current and allowable voltage of the first power feeder 7c received from the first power feeder 7c, the allowable current and allowable voltage of the first power feeder 7e, the allowable current, allowable voltage, and current consumption of the servo driver 6b, and the allowable current and allowable voltage of the functional unit 5b. Furthermore, the notification unit 913 of the information unit 9 provided in the distributor 4 notifies the first power feeder 7a that the first power feeder 7b and the first power feeder 7c are connected downstream of the distributor 4, that the functional unit 5a is connected downstream of the first power feeder 7b, that the first power feeder 7d is connected downstream of the functional unit 5a, that the servo driver 6a is connected downstream of the first power feeder 7d, and that the servo driver 6a is the final stage. The notification unit 913 of the information unit 9 provided in the distributor 4 also notifies the first power feeder 7a that the functional unit 5b is connected downstream of the first power feeder 7c, that the first power feeder 7e is connected downstream of the functional unit 5b, that the servo driver 6b is connected downstream of the first power feeder 7e, and that the servo driver 6b is the final stage (T19).

When the first power supply line 7a receives a notification from the power distributor 4, the notification section 913 of the information unit 9 provided on the first power supply line 7a notifies the DC power supply unit 3 of the allowable current and allowable voltage of the first power supply line 7a, the allowable current and allowable voltage of the power distributor 4 received from the power distributor 4, the allowable current and allowable voltage of the first power supply line 7b, the allowable current and allowable voltage of the first power supply line 7d, the allowable current, allowable voltage, and current consumption of the servo driver 6a, the allowable current and allowable voltage of the functional unit 5a, the allowable current and allowable voltage of the first power supply line 7c, the allowable current and allowable voltage of the first power supply line 7e, the allowable current, allowable voltage, and current consumption of the servo driver 6b, and the allowable current and allowable voltage of the functional unit 5b. Furthermore, the notification unit 913 of the information unit 9 provided on the first power feed line 7a notifies the DC power supply unit 3 that the power distributor 4 is connected downstream of the first power feed line 7a, that the first power feed lines 7b and 7c are connected downstream of the power distributor 4, that the functional unit 5a is connected downstream of the first power feed line 7b, that the first power feed line 7d is connected downstream of the functional unit 5a, that the servo driver 6a is connected downstream of the first power feed line 7d, and that the servo driver 6a is the final stage. The notification unit 913 of the information unit 9 provided on the first power feed line 7a also notifies the DC power supply unit 3 that the functional unit 5b is connected downstream of the first power feed line 7c, that the first power feed line 7e is connected downstream of the functional unit 5b, that the servo driver 6b is connected downstream of the first power feed line 7e, and that the servo driver 6b is the final stage (T20).

As described above, the acquisition unit 311 searches the power line communication network by making inquiries in order from the upstream unit to the downstream unit and by sending notifications in order from the downstream unit to the upstream unit, and is able to acquire the layout information and power-related characteristic information of each unit. Furthermore, while the servo driver 6 is operating with power supplied from the DC power supply unit 3, the acquisition unit 311 monitors and acquires the supply current supplied to each unit by processing similar to the processing described with reference to FIG. 6.

<Processing flow>
Fig. 7 is a diagram showing an example of a processing flow of the DC power supply unit 3 in the embodiment. Hereinafter, an example of the processing flow of the DC power supply unit 3 will be described with reference to Fig. 7. The processing illustrated in Fig. 7 is an example of a "power supply control method."

In S1, the acquisition unit 311 of the DC power supply unit 3 acquires the layout information and power-related characteristic information of each unit (distributor 4, functional unit 5, servo driver 6, and first power supply line 7) connected downstream of the DC power supply unit 3 in the servo system 100. During this acquisition, the DC power supply unit 3 supplies the above-mentioned communication current to each unit. The acquisition unit 311 stores the acquired layout information and characteristic information of each unit in the memory unit 92 of the power supply control device 31. The processing of S1 is an example of an "acquisition step."

In S2, the determination unit 312 of the DC power supply unit 3 determines, based on the information acquired in S1, whether or not the configuration allows dangerous power feeding to the power distributor 4, the functional unit 5, the servo driver 6, and the first power feed line 7. If it is determined that the configuration allows dangerous power feeding (YES in S2), the process proceeds to S6. If it is determined that the configuration does not allow dangerous power feeding (NO in S2), the process proceeds to S3. The process of S2 is an example of a "determination step."

In S3, the control unit 313 of the DC power supply unit 3 causes the DC power supply unit 3 to start supplying power to each unit connected downstream of the DC power supply unit 3. For example, the control unit 313 of the DC power supply unit 3 starts supplying a current sufficient to meet the current consumption specified for the servo driver 6 (the current consumption of the servo driver 6, among the characteristic information acquired in S1), so that the servo driver 6 can drive the motor.

In S4, the acquisition unit 311 of the DC power supply unit 3 acquires the supply current supplied to each unit connected downstream of the DC power supply unit 3 when power supply by the DC power supply unit 3 has begun. In the servo system 100, the only unit that consumes current among the units connected downstream of the DC power supply unit 3 is the servo driver 6, so it is sufficient to acquire the supply current of the servo driver 6 here.

In S5, the determination unit 312 of the DC power supply unit 3 determines whether the supply current supplied to the servo driver 6 obtained in S4 has exceeded the current consumption stored in the information unit 9 provided in the servo driver 6, resulting in a configuration in which dangerous power supply occurs. If it is determined that a dangerous power supply occurs (YES in S5), processing proceeds to S6. If a dangerous power supply does not occur (NO in S5), processing proceeds to S4, and power supply by the DC power supply unit 3 continues.

In S6, the control unit 313 stops power supply from the DC power supply unit 3 and issues a warning. The processing of S6 is an example of a "control step."

<Effects of the embodiment>
In this embodiment, the DC power supply unit 3 acquires information on the current consumption, allowable current, and allowable voltage of each unit connected downstream of the DC power supply unit 3, and determines whether or not the configuration is such that unsafe power supply will occur based on the acquired information. If the DC power supply unit 3 determines that the configuration is such that unsafe power supply will occur, the DC power supply unit 3 does not start power supply and issues an alarm. Therefore, according to this embodiment, unsafe power supply can be suppressed.

In this embodiment, while power is being supplied by the DC power supply unit 3, the acquisition unit 311 acquires the supply current supplied to each unit connected downstream of the DC power supply unit 3. If it is determined that the configuration is causing dangerous power supply due to reasons such as an increase in the supply current to a certain unit, the control unit 313 stops power supply from the DC power supply unit 3 and sounds an alarm. Therefore, according to this embodiment, dangerous power supply can be suppressed even in an operating servo system 100.

<First Modification>
In the above-described embodiment, if it is determined that a configuration is causing dangerous power supply, power supply is prohibited from starting if power supply has not yet started, or power supply is stopped if power supply is in progress. In the first modification, a configuration is described in which the current consumption of a certain unit is suppressed if the current consumption of the certain unit is greater than the allowable current of a unit connected upstream of the certain unit. The first modification will be described below with reference to the drawings. Note that the same components as those in the embodiment are designated by the same reference numerals, and their description will be omitted.

Figure 8 is a diagram showing an example of a processing block of the power supply control device 31a in the first modified example. The power supply control device 31a differs from the power supply control device 31 in the embodiment in that it includes a control unit 313a instead of the control unit 313.

When the determination unit 312 determines that the configuration is such that dangerous power supply is occurring, the control unit 313a limits the current supplied from the DC power supply unit 3 to prevent dangerous power supply. For example, if the current consumption of the servo driver 6a is 20A and the allowable current of the first power supply line 7d connected upstream of the servo driver 6a is 10A, the control unit 313a prevents dangerous power supply by limiting the current supplied from the DC power supply unit 3 to the servo driver 6 to 10A.

Figure 9 shows an example of the processing flow of the DC power supply unit 3a in the first modified example. Below, we will explain an example of the processing flow of the DC power supply unit 3a with reference to Figure 9.

In S6a, the control unit 313a limits the current supplied from the DC power supply unit 3 to prevent dangerous power supply.

According to the first variant, the current supplied from the DC power supply unit 3 is limited to a current that can prevent dangerous power supply, making it possible to operate the servo system 100 while avoiding dangerous power supply.

<Other Modifications>
In the embodiment described above, all of the units connected downstream of the DC power supply unit 3, including the first power supply line 7, the power distributor 4, the functional unit 5, and the servo driver 6, are equipped with the information unit 9. That is, all of the units connected downstream of the DC power supply unit 3, including the first power supply line 7, the power distributor 4, the functional unit 5, and the servo driver 6, are configured to respond to inquiries from the DC power supply unit 3. However, in the servo system 100, some of the units connected downstream of the DC power supply unit 3 may not respond to inquiries from the DC power supply unit 3. In such cases, the control unit 313 of the DC power supply unit 3 may stop the power supply to the units that do not respond to inquiries and to the units connected downstream of those units. The control unit 313 can stop the power supply to the units that do not respond by, for example, controlling a breaker located upstream of the units that do not respond. By adopting such a configuration, the DC power supply unit 3 can avoid dangerous power supply.

Furthermore, the control unit 313 of the DC power supply unit 3 may notify the servo driver 6 that power supply will be stopped before stopping the power supply. By sending such a notification, the servo driver 6 can take measures to stop connected motors, etc. before power supply is stopped.

The acquisition unit 311 of the DC power supply unit 3 may also continue to acquire the layout information of the first power feed line 7, power distributor 4, functional unit 5, and servo driver 6 connected downstream of the DC power supply unit 3, even while the servo driver 6 is being driven by power supplied by the DC power supply unit 3. The control unit 313 may then stop power supply by the DC power supply unit 3 if it is unable to acquire the layout information of at least one of the first power feed line 7, power distributor 4, functional unit 5, and servo driver 6 connected downstream of the DC power supply unit 3. By employing such a configuration, it is possible to prevent power supply from continuing if, for example, a wiring connection becomes disconnected.

In the embodiment described above, communication between the DC power supply unit 3, the first power supply line 7, the power distributor 4, the functional unit 5, and the servo driver 6 is performed by power line communication via the first power supply line 7. However, communication between the units may also be performed, for example, via a communication cable provided alongside the first power supply line 7.

In the embodiment described above, no power receiving device was connected downstream of the servo driver 6, but a power receiving device that operates by receiving power from the DC power supply unit 3 may also be connected downstream of the servo driver 6.

In the embodiment described above, the DC power supply unit 3 determines whether a dangerous power supply is occurring and stops the power supply if a dangerous power supply is occurring. However, this processing may also be performed by an external power supply control device connected to the DC power supply unit 3, or a programmable logic controller (PLC) that operates by receiving power from the DC power supply unit 3. Furthermore, the power supply control methods illustrated in Figures 7 and 9 may be performed by multiple control devices and current sensors working together, rather than by a single power supply control device.

The embodiments and variations disclosed above can be combined with each other.

<Appendix 1>
A power supply control device (31) for controlling power supply from the power source (3) in a system (100) including a power source (3), a power receiving device (6) that operates by receiving power from the power source (3), and a power supply cable (7) that connects the power source (3) and the power receiving device (6),
an acquisition unit (311) that acquires arrangement information of the power supply cable (7) and the power receiving device (6) in the system (100) and acquires characteristic information related to the power of the power supply cable and the power receiving device;
a determination unit (312) that determines whether or not power supply is possible based on the arrangement information and the characteristic information;
and a control unit (313) that prohibits the power source (3) from starting power supply when the determination by the determination unit (312) is negative.
Power supply control device (31).

<Appendix 2>
A power supply control method (FIG. 7) for controlling power supply from a power source (3) in a system (100) including a power source (3), a power receiving device (6) that operates by receiving power from the power source (3), and a power supply cable (7) that connects the power source (3) and the power receiving device (6), comprising:
an acquisition step (S1) of acquiring arrangement information of the power feed cable and the power receiving device in the system, and acquiring characteristic information related to the power of the power feed cable and the power receiving device;
a determination step (S2) of determining whether or not power supply is possible based on the arrangement information and the characteristic information;
and a control step (S6) of prohibiting the power source from starting power supply when the determination in the determination step is negative.
Power supply control method (Figure 7).

DESCRIPTION OF SYMBOLS 1 AC power supply 2 Breaker 3 DC power supply unit 4 Power distributor 5 Functional unit 6 Servo driver 7 First power feed line 8 Second power feed line 9 Information unit 31 Power feed control device 31a Power feed control device 51 Breaker 52 Noise filter 91 CPU
92: Storage unit 93: Signal processing unit 100: Servo system 311: Acquisition unit 312: Determination unit 313: Control unit 313a: Control unit 911: Search unit 912: Inquiry unit 913: Notification unit B1: Connection bus

Claims (8)

A power supply control device that controls power supply from a power source in a system including a power source, a power receiving device that operates by receiving power from the power source, and a power supply cable that connects the power source and the power receiving device,
an acquisition unit that acquires arrangement information of the power feed cable and the power receiving device in the system, and acquires characteristic information related to the power of the power feed cable and the power receiving device;
a determination unit that determines whether or not power supply is possible based on the arrangement information and the characteristic information;
a control unit that prohibits the power source from starting power supply when the determination by the determination unit is negative ,
the characteristic information includes information indicating an allowable current of the power supply cable and information indicating a current consumption of the power receiving device,
the determination unit makes a negative determination when the allowable current of the power supply cable connected closer to the power source than the power receiving device is lower than the current consumption of the power receiving device.
Power supply control device. the acquisition unit acquires the arrangement information and the characteristic information through power line communication using the power supply cable.
The power supply control device according to claim 1 . the acquisition unit causes the power source to supply a predetermined current for performing the power line communication, and acquires the arrangement information and the characteristic information.
The power supply control device according to claim 2 . the characteristic information includes information indicating an allowable current of the power supply cable and information indicating a current consumption of the power receiving device,
When the consumed current exceeds an allowable current of the power supply cable connected to the power supply side of the power receiving device after the power supply starts supplying power , the control unit limits the current supplied by the power supply to equal to or less than the allowable current.
The power supply control device according to any one of claims 1 to 3 . the characteristic information includes information indicating an allowable current of the power supply cable,
the acquisition unit monitors a supply current supplied from the power source to the power receiving device while the power receiving device is being driven by receiving power from the power source;
the control unit stops power supply from the power source when the supply current exceeds an allowable current of the power supply cable connected to the power source side of the power receiving device.
The power supply control device according to any one of claims 1 to 4 . the control unit continues to acquire the arrangement information of the power supply cable and the power receiving device while the power receiving device is being driven by receiving power from the power source;
the control unit stops power supply from the power source when the acquisition unit has not acquired the placement information of at least one of the power supply cable and the power receiving device.
The power supply control device according to any one of claims 1 to 5 . The control unit notifies the power receiving device of the stop of power supply before causing the power source to stop power supply.
The power supply control device according to any one of claims 1 to 6 . A power supply control method for controlling power supply from a power supply in a system including a power supply, a power receiving device that operates by receiving power from the power supply, and a power supply cable that connects the power supply and the power receiving device, comprising:
an acquiring step of acquiring arrangement information of the power feed cable and the power receiving device in the system, and acquiring characteristic information related to the power of the power feed cable and the power receiving device;
a determination step of determining whether or not power supply is possible based on the arrangement information and the characteristic information;
a control step of prohibiting the power source from starting power supply when the determination step results in a negative determination,
the characteristic information includes information indicating an allowable current of the power supply cable and information indicating a current consumption of the power receiving device,
In the determination step, a negative determination is made when the allowable current of the power supply cable connected closer to the power source than the power receiving device is lower than the current consumption of the power receiving device.
Power supply control method.