Power supply system and power supply unit

Abstract

To provide a device including a plurality of load devices, that can satisfy the user's needs suitably.SOLUTION: A power supply system is formed in a predetermined device to which power is supplied from an external power source system and includes a first power supply route provided in the predetermined device, and a first power converter to which the power is input from the power source system, in which the power is converted, and from which first power is output to the first power supply route.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power supply system in an apparatus that receives power from an external power supply system, and a power supply unit that can be applied to the system. [Background technology]

[0002] An inverter device for supplying power to a load device driven by AC power is a power supply device that converts input DC power into AC power suitable for driving the load device and supplies the converted power. Patent Documents 1 and 2 are examples of prior art that disclose power supply systems that include an inverter device and supply power for driving the load device. Patent Document 1 illustrates a power supply system that supplements a load device driven by commercial power with power generated by natural energy, while Patent Document 2 illustrates a system configuration in which stored power in a battery is converted by a DC-DC converter and supplied to an inverter. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-128102 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-27870 Summary of the Invention [Problem to be solved by the invention]

[0004] Equipment such as machine tools and conveyance devices installed in factories and the like incorporate load devices such as servo motors, and power supply devices such as inverters for driving and controlling these devices are also installed. Generally, equipment installed in factories and the like includes many drive axes, and the number of such equipment devices is large. As a result, the number of load devices that require drive current and are driven and controlled becomes enormous, and the work of laying the wiring for supplying power to them becomes complicated.

[0005] Furthermore, because facility devices are controlled and driven to perform the operations desired by users, the design specifications related to their internal power supply vary according to the user's requirements. For example, the power specifications required vary depending on the location of the facility device and the operation content. Therefore, in order to provide facility devices that accurately meet the user's requirements, it is necessary to meet the power supply specifications according to those requirements, which can lead to increased costs.

[0006] The present invention has been made in view of the above problems, and has an object to provide a technique for realizing a power supply that can suitably satisfy user requirements in an apparatus having a plurality of load devices. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a power supply system in which a first power converter is provided for a predetermined device having a plurality of load devices, which controls power conversion between an external power supply system and the inside of the predetermined device, and the power adjusted to a desired voltage by the first power converter is output to a first power supply path within the predetermined device. By adopting such a configuration, it becomes possible to suitably respond to various user requirements regarding power supply. Note that, in this application, power conversion refers to changing one or more parameters, such as voltage, current, frequency (including DC as zero frequency), phase, and number of phases, which are variables that characterize the form of power transmitted for use in an electrical system. Furthermore, the power conversion can convert from one form to another, which are included in various power forms including AC, DC, square wave, triangular wave, etc. This also includes converting to a state.

[0008] Specifically, the present invention provides a power supply system formed within a predetermined device that receives power from an external power supply system, the power supply system including: a first power supply path configured to be able to supply power to multiple load devices within the predetermined device; and a first power converter configured to receive power from the power supply system, convert the power, and output the first power to the first power supply path. Examples of the first power converter include a DC-DC converter, an AC-DC converter, and an AC-AC converter. The first power converter converts externally input power into first power and outputs the first power to the first power supply path. The first power converter is capable of converting the input power, for example, by boosting, bucking, or boosting / bucking a voltage that characterizes the power. The output first power is then supplied to multiple load devices within the predetermined device via the first power supply path. The first power converter may be configured to accept input of power in which a predetermined first parameter that characterizes the form of power in the power supply system has a first fluctuation range. Examples of the first parameters include voltage, current, frequency (including DC as zero frequency), phase, and number of phases, and these parameters are set appropriately according to the common technical knowledge of those skilled in the art. The first fluctuation range can be set appropriately based on the fluctuation range of the above parameters, such as voltage, that characterize the form of power in the external power supply system. With this configuration, the power flowing through the first power supply path formed within the power supply system can be made to have a form that suits the user's purpose.

[0009] Here, the power supply system may further include a second power converter connected to the first power supply path and configured to convert the first power and output a second power; a load power supply path configured independently of the first power supply path and configured to output the second power; and a plurality of power supply devices connected to the load power supply path and configured to convert the input second power as load power for each of the plurality of load devices and supply the converted power. The predetermined device forming the power supply system includes a plurality of load devices driven by a plurality of power supply devices. The plurality of load devices are not limited to a specific type of device as long as they are driven by load power output from the power supply devices. For example, an AC-driven servo motor or the like can be exemplified as the load device, and in this case, an inverter device can be exemplified as the power supply device. Alternatively, a heater or the like can be exemplified as the load device, and in this case, an ON / OFF switch can be exemplified as the power supply device. The predetermined device may be a machine tool or a conveyance device in which the servo motor or heater is installed. The predetermined device itself receives power from an external power supply system to drive the load devices. For example, the predetermined device may be connected to at least one of a DC power supply system and an AC power supply system that are laid over a relatively wide area such as a factory.

[0010] The second power converter is a converter capable of supplying suitable power according to the specifications of the power supply device, and examples thereof include a DC-DC converter, an AC-DC converter, and an AC-AC converter. The second power converter converts a first power into a second power and outputs the second power to a load power supply path. The second power converter is capable of converting the first power, for example, by stepping up, stepping down, or stepping up / down a voltage that characterizes the first power. The power conversion capability of the second power converter may be the same as or different from that of the first power converter. The load power supply path to which the second power converter outputs the second power is a supply path independent from the first power supply path, and is a supply path through which the second power flows to each of the multiple power supply devices as power for driving the load devices. Note that the second power converter may be configured to allow input of power with a second fluctuation range, where a predetermined second parameter characterizing the form of power in the first power supply path is a second parameter. The second parameter may be a voltage, a current, a frequency (including a zero frequency and a Examples of such parameters include the phase and number of phases, and these parameters are within the common technical knowledge of a person skilled in the art. The second fluctuation range can be set appropriately based on the fluctuation range of the above-mentioned parameters such as voltage that characterize the form of power in the first power supply path.

[0011] With this configuration, the first power supply path and the load power supply path formed in the power supply system can suitably adjust the form of power supplied by the first power converter and the second power converter, respectively, in accordance with user requirements. Furthermore, even if the form of grid power differs depending on the location where a predetermined device is installed, by equipping the predetermined device with the power supply system of the present invention, it can suitably accommodate different forms of input power.

[0012] Furthermore, when the voltage of the first power is adjusted to a relatively high voltage by the first power converter, the current flowing through the first power supply path can be reduced. This allows the power cable forming the first power supply path to be thinner, thereby reducing the burden of wiring work within the device. Note that if the voltage in the first power supply path is not suitable for driving the load device as it is, the second power converter can transform it to a suitable voltage and output it as the second power to the load power supply path.

[0013] In the power supply system described above, the external power supply system may be a DC power system that supplies DC power, the first power converter may be configured to receive DC power from the power supply system, convert the DC power, and output the first power, which is DC power, to the first power supply path, and the second power converter may be configured to convert the first power and output the second power, which is DC power, to the load power supply path. Alternatively, the external power supply system may be an AC power system through which AC power flows, and the first power converter may be configured to receive AC power from the power supply system, convert the AC power, and output the first power, which is DC power, to the first power supply path.

[0014] The power supply system described above may further include a power supply unit including the second power converter, the load power supply path, and the plurality of power supply devices, and in which the connection relationship between the load power supply path and the plurality of power supply devices is determined to be a predetermined relationship. By unitizing the second power converter and the plurality of power supply devices in this manner, handling of the second power converter, the load power supply path, and the plurality of power supply devices becomes easier. The benefits of unitization become even greater, especially as the number of power supply devices increases. Furthermore, since the power supply system includes the first power converter, inrush current can be limited, eliminating the need for a configuration to prevent inrush current for each of the plurality of power supply devices in the power supply unit. The power flowing through the load power supply path in the power supply unit may be DC power, AC power, or other forms of power.

[0015] Furthermore, when the power supply device is an inverter device, when regenerative power is generated by a regenerative operation of one of the load devices corresponding to any of the plurality of power supply devices, the regenerative power may be consumed by a power running operation of a load device other than the one load device via the load power supply path. With this configuration, the regenerative power can be consumed within the power supply unit, and an influence on the first power supply path outside the unit can be avoided.

[0016] Here, the power supply system may include a plurality of the power supply units. In this way, even if a given device is equipped with many load devices and a corresponding number of power supply units, it is possible to easily realize a power supply appropriate for each load device by connecting the plurality of power supply units via the first power supply path.

[0017] Furthermore, when the power supply system includes a plurality of power supply units, it is preferable that the second power converters included in each of the plurality of power supply units are daisy-chain connected via the first power supply path. By configuring in this way, it is possible to obtain a unique form that allows the connection form of all the power supply devices included in the power supply system to be grasped. As a result, the inductance and capacitance of the first power supply path and the load power supply path can be easily understood. This makes it possible to preferably suppress in advance the excessive current caused by the transformer.

[0018] Furthermore, when the power supply system includes a plurality of power supply units and the power supply devices are inverter devices, when regenerative power is generated in one of the plurality of power supply units by a regenerative operation of a load device corresponding to one of the plurality of power supply devices included in the one power supply unit, the regenerative power may be consumed by another of the plurality of power supply units via the first power supply path. By adopting such a configuration, the regenerative power can be consumed within a specific device, thereby avoiding impact on an external DC power system. Furthermore, when the regenerative power generated in the one power supply unit causes a specific first parameter characterizing the form of power in the first power supply path to exceed a first threshold, the first power converter may cause the regenerative power to flow to the power supply system.

[0019] The power supply system described above may further include a unit abnormality detection unit that detects an abnormality related to the power supply in the power supply unit based on the converted power in the second power converter and the converted power in the multiple power supply devices. When no abnormality occurs in the power supply unit, the unit abnormality detection unit can detect an abnormality based on the fact that the converted power in the second power converter and the converted power in the multiple power supply devices generally match. Furthermore, when DC power is flowing through the power supply system, the time required for power calculation for abnormality detection can be relatively short. Therefore, abnormality detection can be performed quickly. The power supply system may also further include a load device abnormality detection unit that detects an abnormality related to the multiple load devices based on the converted power in the multiple power supply devices and the power consumption consumed to drive the multiple load devices to which power is supplied from the multiple power supply devices. Even with this configuration, abnormalities in the load devices can be quickly detected by comparing the converted power in the multiple power supply devices with the power consumption of the multiple load devices. When some driven object is connected to the output shaft of a plurality of load devices, the power consumption is calculated taking into consideration the inertia, friction, etc. of the driven object.

[0020] The power supply system described above may further include an apparatus abnormality detection unit that detects an abnormality related to the power supply of the predetermined apparatus based on the converted power in the first power converter and the converted power in the plurality of power supply devices, or based on the converted power in the first power converter and the converted power in the second power converter. When no abnormality occurs in the predetermined apparatus, the converted power in the first power converter generally matches the sum of the converted powers in the plurality of power supply devices or matches the converted power in the second power converter, and thus the apparatus abnormality detection unit can detect the abnormality. Furthermore, when DC power is flowing within the power supply system, the time required for power calculation for abnormality detection can be relatively short. Therefore, abnormality detection can be performed quickly.

[0021] Furthermore, in the power supply system described above, when a device other than the predetermined device is connected to the power supply system to supply power to the other device, regenerative power generated by the other device may flow into the power supply system, and when a predetermined second parameter characterizing the form of power in the power supply system exceeds a second threshold, power conversion may be performed via the first power converter of the predetermined device. With this configuration, when regenerative power is generated by the other device, power is drawn into the predetermined device, thereby suitably suppressing overvoltage in the power supply system and maintaining safety in the power supply. The power drawn into the predetermined device may be used for a predetermined power consumption process within the predetermined device. Alternatively, if the power supply system further includes a power storage device connected to the first power supply path or the load power supply path and capable of storing and discharging, when the regenerative power is generated by the other device, the DC power converted by the first power converter and supplied to the first power supply path or the load power supply path may be stored in the power storage device. .

[0022] Here, the present invention can be understood from the aspect of a power supply unit included in a power supply system formed within a predetermined device having a plurality of load devices and receiving power from an external DC power supply system, and converting input DC power to supply load power to each of the plurality of load devices. For example, the power supply unit includes a power converter that converts the input DC power to output predetermined DC power, a load power supply path from which the predetermined DC power is output, and a plurality of power supply devices connected to the load power supply path that convert the input predetermined DC power as load power for each of the plurality of load devices and supply it. Then, a connection relationship between the plurality of power supply devices and the load power supply path is determined to be a predetermined relationship.

[0023] Furthermore, with regard to the above-mentioned power supply unit, in the power supply system, DC power may be input from the DC power supply system to a first power converter, the DC power may be converted by the first power converter, and the converted DC power may be input to the power supply unit as first DC power. [Effects of the Invention]

[0024] It is possible to provide a technology for realizing a power supply that can suitably satisfy user requirements in a device having a plurality of load devices. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a diagram showing a schematic configuration of a power supply system installed in a factory. [Figure 2] FIG. 1 is a first diagram schematically illustrating a power supply configuration of an equipment. [Figure 3] FIG. 2 is a second diagram schematically illustrating the power supply configuration of the facility device. [Figure 4] FIG. 3 is a third diagram schematically illustrating the power supply configuration of the facility device. [Figure 5] 10 is a first flowchart of control relating to a DC-DC converter executed in an equipment facility when regenerative power is generated. [Figure 6]10 is a second flowchart of control relating to a DC-DC converter executed in an equipment facility when regenerative power is generated. [Figure 7] FIG. 4 is a fourth diagram schematically illustrating the power supply configuration of the facility device. [Figure 8] 10 is a flowchart of control relating to abnormality detection executed in the facility device. DETAILED DESCRIPTION OF THE INVENTION

[0026] <Application example> An application example of the power supply system of the present application will be described below with reference to the drawings. FIG. 1 is a diagram showing the schematic configuration of a power supply system installed in a factory. In FIG. 1, the factory site area is indicated by R1, and a large number of pieces of equipment 1 are arranged in this area R1. Each piece of equipment 1 is designed with a motor 14 (shown in FIG. 2) as a load device so as to achieve a predetermined purpose (such as processing or transport) in the factory. Examples of equipment 1 include various types of mechanical devices (e.g., an arm of an industrial robot or a transport device), and a motor 14 is incorporated within the equipment 1 as a load device that drives the equipment 1. For example, the motor 14 is an AC servo motor. An encoder is attached to the motor 14, and the encoder transmits a parameter signal related to the operation of the motor 14 to a servo driver (including an inverter device 13 described below) as feedback. The parameter signal (hereinafter referred to as a feedback signal) transmitted as feedback includes, for example, position information regarding the rotational position (angle) of the rotational shaft of the motor 14, information about the rotational speed of the rotational shaft, etc.

[0027] The servo driver receives an operation command signal related to the operation (motion) of the motor 14 from a programmable logic controller (PLC) (not shown) via a network within the facility equipment 1. and a feedback signal output from an encoder connected to the motor 14. The servo driver performs servo control for driving the motor 14, i.e., calculates a command value for the operation of the motor 14, based on the operation command signal from the PLC and the feedback signal from the encoder, and controls the inverter device 13 to supply a drive current to the motor 14 so that the operation of the motor 14 follows the command value. The inverter device 13 corresponds to the power supply device disclosed in the present application.

[0028] Here, the power supply in the facility equipment 1 will be described with respect to the drive current supplied to the motor 14. AC power is supplied to a site area R1 of the factory from an external AC power source 100 via a power supply system L1. The supplied AC power is converted to DC power by an AC-DC converter 101 and output to a DC power supply system L2 within the site area R1. From the perspective of the power supply system, the area to which DC power is supplied by the DC power supply system L2 is referred to as "R2," and multiple facility equipment 1 can receive DC power from the common DC power supply system L2 formed in the area R2. Although not shown, an AC power supply system that uses AC power supplied from the external AC power source 100 is also formed within the site area R1 of the factory. The facility equipment 1 is provided with devices that operate on AC power (for example, the above-mentioned PLC, etc.), and these devices receive AC power from the AC power supply system.

[0029] Here, the DC power supply path within the facility equipment 1 will be described with reference to FIG. 2. This DC power is supplied to the inverter device 13, which generates a drive current for the motor 14. As described above, the facility equipment 1 receives DC power from the DC power supply system L2 formed in the factory area R2. This supplied DC power is input to the DC-DC converter 2 and converted to a predetermined DC voltage. For example, the DC voltage input from the DC power supply system L2 may be 1000 V and converted to a DC voltage of 200 V or 400 V by the DC-DC converter 2. The converted DC power is output to the first power supply path 3 within the facility equipment 1. The DC-DC converter 2 is also equipped with commonly used circuit breakers, noise filters, and the like. The DC-DC converter 2 is also equipped with a capacitor for mitigating voltage fluctuations in the first power supply path 3.

[0030] The facility equipment 1 is equipped with multiple motors 14 as load devices. When identifying each motor individually, a symbol (a, b, c, etc.) for individual identification is added after the reference number 14, as shown in FIG. 2. When it is not necessary to identify each motor, it is represented by only the reference number 14. In the embodiment shown in FIG. 2, the facility equipment 1 is equipped with six motors 14a to 14f, each of which is an AC motor. In the facility equipment 1, an inverter device 13 is provided corresponding to each motor. As with the motors 14, a symbol (a, b, c, etc.) for individual identification is added after the reference number 13 for each inverter device 13. Therefore, six inverter devices 13 are required to accommodate the six motors 14.

[0031] In the embodiment disclosed herein, six inverter devices 13, one DC-DC converter 11, and load power supply paths 12 connecting the output sides of the DC-DC converters 11 to the respective inverter devices 13 are combined to form a single power supply unit 10. The power supply unit 10 is formed such that the six inverter devices 13 are connected to the load power supply paths 12 in a connection relationship such that each inverter device 13 receives power directly from the load power supply path 12, as shown in FIG. 2 . The load power supply path 12 is connected to the output side of the DC-DC converter 11. The input side of the DC-DC converter 11 is connected to the first power supply path 3, and the DC power of the first power supply path 3 is converted by the DC-DC converter 11 to a predetermined DC voltage and output to the load power supply path 12. The DC voltage of the load power supply path 12 is a voltage suitable for driving the inverter devices 13. The DC-DC converter 11 is also equipped with commonly used circuit breakers, noise filters, and the like. Furthermore, the DC-DC converter 11 is also equipped with a capacitor for mitigating voltage fluctuations in the load power supply line 12 .

[0032] The facility equipment 1 also has a control unit 70. The control unit 70 is composed of a processor (microcontroller, CPU, etc.) and its peripheral circuits. It is electrically connected to the DC-DC converter 2 and the DC-DC converter 11, and exchanges information related to each converter and controls the voltage conversion by each converter. The control unit 70 may be included in the PLC, or alternatively, may be included in a control device configured differently from the PLC. The control unit 70 is also electrically connected to each inverter device 13 and exchanges information related to each inverter device 13. The control unit 70 is also electrically connected to a sensor (not shown) that detects the voltage of the first power supply path 3 and a sensor (not shown) that detects the voltage of the load power supply path 12, and is configured to be able to detect each voltage. The control unit 70 is also connected to facility equipment 1 other than the facility equipment 1 in which the control unit 70 is located so that information can be exchanged between the facility equipment 1.

[0033] In the facility equipment 1 configured as described above, the DC voltage of the first power supply path 3 can be adjusted to a voltage desired by the user by the DC-DC converter 2. In particular, when the DC voltage of the first power supply path 3 is adjusted to a relatively high voltage by the DC-DC converter 2, the current flowing through the first power supply path 3 can be reduced. This allows the power cable forming the first power supply path 3 to be made thinner, thereby reducing the burden of wiring installation work within the facility equipment 1. This is particularly useful when the length of the first power supply path 3 is long due to the structure of the facility equipment 1. Note that if the DC voltage of the first power supply path 3 is not suitable for driving the motor 14 as it is, the DC-DC converter 11 can transform it to a suitable voltage and adjust the DC voltage of the load power supply path 12. The DC-DC converter 2 is preferably configured to be able to apply a DC voltage having a first fluctuation range from the DC power supply system L2. In this way, the DC-DC converter 2 can respond to input fluctuations, and therefore can also respond favorably to voltage fluctuations in the AC power supply 100 and output fluctuations in the AC-DC converter 101. Furthermore, even if the same facility equipment 1 is installed in a location where the voltage of the external DC power supply system is different, the facility equipment 1 can be operated favorably, i.e., the facility equipment 1 can be installed regardless of location, which improves user convenience.

[0034] Furthermore, the DC voltage of the load power supply path 12 can be adjusted to a voltage desired by the user by the DC-DC converter 11. By adopting such a configuration, it is possible to stabilize the power supply for driving the inverter device 13. It is preferable that the DC-DC converter 11 is configured so that a DC voltage having the second fluctuation range can be input from the first power supply path 3. Being able to respond to input fluctuations in this way makes it possible to maintain a stable power supply.

[0035] Furthermore, the DC-DC converter 11 and inverter device 13, including the load power supply path 12, are unitized as an integrated unit as a power supply unit 10. Unitizing the area from the DC-DC converter 11 to the inverter device 13 in this way makes it easier to handle the DC-DC converter 11, the load power supply path 12, and the inverter device 13. In particular, when the number of inverter devices is large (six devices) as shown in FIG. 2, the number of power cables connecting each inverter device 13 and the DC-DC converter 11 increases, so unitization makes it extremely easy to wire the power supply in the facility equipment 1. This is an extremely useful effect, as it reduces the burden of installation work and minimizes installation errors.

[0036] Furthermore, by forming the power supply unit 10 including the DC-DC converter 11, it is possible to adjust the DC voltage of the load power supply line 12 in the unit to a desired voltage depending on the purpose. For example, when the DC voltage of the load power supply line 12 is set to a relatively high level, it is possible to make the power cable forming the load power supply line 12 thinner. When the DC voltage is set relatively low, the withstand voltage performance of devices and electrical components related to the power supply can be reduced, thereby enabling their miniaturization. Furthermore, in the facility equipment 1 shown in Fig. 2, a DC-DC converter 2 is installed between the DC power supply system L2 and the power supply unit 10. Therefore, it is not necessary to provide a configuration for preventing inrush current for each inverter device 13 in the power supply unit 10.

[0037] <Variation 1> Next, a modified example of the DC power supply path in the facility equipment 1 will be described with reference to FIG. 3. In the embodiment shown in FIG. 3, the facility equipment 1 is equipped with 15 motors 14, 24, and 34, and is configured so that the facility equipment 1 operates as desired using each motor. Of the 15 motors 14, 24, and 34, a power supply unit 10 supplies load power to six motors 14a to 14f, a power supply unit 20 supplies load power to six motors 24a to 24f, and a power supply unit 30 supplies load power to three motors 34a to 34c. The power supply unit 10 shown in FIG. 3 is the same as the power supply unit 10 shown in FIG. 2. Furthermore, the power supply unit 20 is substantially the same as the power supply unit 10, and includes a DC-DC converter 21, a load power supply path 22, and six inverter devices 23 corresponding to the six motors 24. Furthermore, the power supply unit 30 includes a DC-DC converter 31, a load power supply path 32, and three inverter devices 23 corresponding to the three motors 34. Furthermore, in the facility equipment 1, the DC-DC converters 11, 21, 31 included in each power supply unit are daisy-chain connected in sequence via a first power supply path 3.

[0038] 3 also has a control unit 70. The control unit 70 is electrically connected to the DC-DC converter 2 and each power supply unit, and is configured to control each DC-DC converter, exchange related information, exchange information related to each inverter device, detect voltages in each supply path, etc.

[0039] In this manner, by connecting multiple power supply units in the facility equipment 1 to form a DC power supply path, it is easy to form the DC power supply path even when multiple motors 14, 24, 34 and their corresponding inverters 13, 23, 33 are installed. As described above, when the DC voltage of the first power supply path 3 is adjusted to a relatively high value by the DC-DC converter 2, the power cable forming the first power supply path 3 connecting the multiple power supply units can be made thinner, thereby making it easier to form the DC power supply path. Furthermore, generally, if all the inverters in the DC power supply path in the facility equipment 1 were connected arbitrarily, various connection configurations would be created depending on the user's intention, which could result in unexpected excessive current due to inductance and capacitance in the first power supply path and the load power supply path. However, by connecting the power supply units in a daisy chain as described above, the connection configuration of all the inverters in the facility equipment 1 can be uniquely determined, thereby making it possible to preferably suppress the excessive current in advance.

[0040] <Variation 2> A further modification of the DC power supply path in the facility equipment 1 when a plurality of power supply units are provided in the facility equipment 1 will be described with reference to Fig. 4. The difference between the configuration shown in Fig. 4 and the configuration shown in Fig. 3 is the connection configuration of DC-DC converters 11, 21, 31 included in the power supply units. That is, in the facility equipment 1 shown in Fig. 4, the first power supply path 3 connected to the DC-DC converter 2 is formed so that it branches off to each of the power supply units 10, 20, 30 by a connector 4. Even in the configuration shown in Fig. 4, the formation of the DC power supply path is easy despite the installation of a large number of motors 14, 24, 34 and their corresponding inverter devices 13, 23, 33. Furthermore, by increasing the voltage of the first power supply path 3, the power cable forming the first power supply path 3 can be made thinner.

[0041] <Variation 3> In the configuration shown in FIGS. 1 to 4, AC power supplied from the power supply system L1 is converted into DC power of a predetermined voltage by the AC-DC converter 101 and supplied to the DC power supply system L2. Alternatively, AC power may be supplied to the power supply system L2. In this case, the conversion may be performed by a different conversion device instead of the AC-DC converter 101, or the AC power from the power supply system L1 may directly flow into the power supply system L2. In this configuration, an AC-DC converter can be used as a power conversion device corresponding to the DC-DC converter 2 in the facility equipment 1. The DC power output by the AC-DC converter is supplied to a DC-DC converter 11, such as a power supply unit 10, and used as load power for driving motors connected to each unit. Alternatively, the facility equipment 1 may have two power supply systems L2: one system to which AC power is supplied and one system to which DC power is supplied. In this case, a power conversion device corresponding to each system is preferably installed.

[0042] Alternatively, a DC-powered device (e.g., a heater) may be used as the load device mounted on the facility equipment 1 instead of the motor 14. In this case, instead of the inverter device 13 in the power supply unit 10, an ON / OFF switch that controls the power supply to the heater is installed in the power supply unit 10 as the power supply device. That is, in the power supply unit 10, six ON / OFF switches are connected to the load power supply path 12, and each ON / OFF switch is connected to each heater. Alternatively, as shown in FIGS. 3 and 4, when multiple power supply units are installed in the facility equipment 1, the power supply units may be mixed to supply power to multiple types of load devices, such that some power supply units supply power to the motor and other power supply units supply power to the heater. Even if the specifications of the DC power to be supplied differ depending on the type of load device, the DC-DC converter included in each power supply unit can create a power supply environment suitable for driving the load device, so that the power supply units can be connected via a common power supply path (first power supply path 3).

[0043] <Power supply control 1> Control related to power supply when multiple power supply units are provided in the facility equipment 1 as shown in FIGS. 3 and 4 will be described with reference to FIG. 5. The power supply control shown in FIG. 5 is realized by repeatedly executing a predetermined program at predetermined intervals in the control unit 70. First, in S101, it is determined whether any of the power supply units is generating regenerative power. For example, the acceleration / deceleration operation of the motor can be determined from instructions from a servo driver (not shown), thereby determining the amount of regenerative power that can be generated. Furthermore, from the perspective of the degree of impact on the first power supply path 3 in the facility equipment 1, a positive determination may be made in S101 only when the regenerative power exceeds a certain level. Because regenerative power varies depending on the load inertia and rotational speed of the movable shaft, not all regenerative operations necessarily affect the first power supply path 3. If a positive determination is made in S101, the process proceeds to S102. If a negative determination is made, the control ends.

[0044] In S102, the power supply unit that is generating regenerative power in S101 determines whether or not the regenerative power needs to be consumed by another power supply unit. Here, when regenerative power is generated by one motor belonging to one power supply unit, the regenerative power may be consumed by the power running operation of a motor other than the one motor via the load power supply path. In such a case, the determination in S102 may be made taking into account the consumption of the regenerative power. For example, if the regenerative power is generated by the operation of the motor 14a belonging to the power supply unit 10, If the regenerative power is generated due to the regenerative power being generated, and if the regenerative power can be consumed by the power running operation of the other motors 14b to 14f belonging to the same power supply unit 10, it can be determined in S102 that there is no need for the other power supply units to consume it. Also, if the operation of the other motors 14b to 14f is not enough to consume the regenerative power and the DC voltage of the load power supply path 12 rises above a predetermined reference value, it can be determined in S102 that there is a need for the other power supply units to consume it. Also, if each power supply unit is provided with a regenerative resistor for consuming regenerative power, and the DC voltage of the load power supply path 12 rises above a predetermined reference value due to regenerative power exceeding the consumption capacity of the regenerative resistor, it can be determined in S102 that there is a need for the other power supply units to consume it. If a positive determination is made in S102, the process proceeds to S103, and if a negative determination is made in S102, the process proceeds to S105.

[0045] Next, if a positive determination is made in S102, a power supply unit capable of consuming the surplus regenerated power is identified in S103. This identification can be achieved based on the degree of power consumption margin by regenerative resistors among power supply units that are not generating regenerative power. Next, in S104, the power conversion process of the necessary DC-DC converters is controlled so that power is transferred from the power supply unit generating regenerative power to the power supply unit identified in S103 via the first power supply path 3. For example, if the regenerated power of power supply unit 10 is to be consumed by power supply unit 20, DC-DC converters 11 and 21 are controlled. When the processing of S104 is completed, the process proceeds to S105.

[0046] In S105, it is determined whether the DC voltage of the first power supply path 3 exceeds a predetermined first voltage (corresponding to the first threshold value of the present application). The predetermined first voltage is set based on, for example, the viewpoint of electrical safety within the facility equipment 1. Regardless of the power consumption in the power supply unit that is not generating other regenerative power, the possibility remains that the DC voltage of the first power supply path 3 will rise excessively, and therefore, the processes from S105 onward are performed. If a positive determination is made in S105, the DC-DC converter 2 is controlled in S106, and the DC power of the first power supply path 3 is output to the DC power supply system L2 outside the facility equipment 1. This reduces the DC voltage of the first power supply path 3.

[0047] In this way, by following the control shown in Figure 5, the regenerative power generated in the facility equipment 1 is processed appropriately and the power flow to the DC power supply system L2 is suppressed, thereby ensuring the safety of both the facility equipment 1 and the DC power supply system L2.

[0048] <Power supply control 2> Control related to power supply when multiple facility devices 1 are provided in a DC power supply system L2 as in Fig. 1 will be described with reference to Fig. 6. The control of power supply shown in Fig. 6 is realized by repeatedly executing a predetermined program at predetermined intervals in a control unit 70. As described above, the control units 70 of the facility devices 1 can communicate with each other and can obtain information related to power supply in other facility devices 1 from the other facility devices 1.

[0049] First, in S201, it is determined whether or not regenerative power is generated in another facility device 1 other than the facility device 1 for which this control is being executed. For example, the generation of regenerative power can be determined from the operation of the motors in the entire facility device 1. If a positive determination is made in S201, the process proceeds to S202. In S202, it is determined whether or not the DC voltage of the DC power supply system L2 exceeds a predetermined second voltage (corresponding to the second threshold value of the present application). This determination process takes into account the case where regenerative power generated in the other facility device 1 cannot be fully consumed by the other facility device 1 and flows into the DC power supply system L2, causing an increase in the DC voltage there. The predetermined second voltage is set based on, for example, the electrical safety of the DC power supply system L2. If a positive determination is made in S202, the process proceeds to S203.

[0050] In S203, it is determined whether the surplus regenerative power can be consumed by the facility equipment 1 itself. This determination can be made based on the degree of power consumption margin provided by the regenerative resistor of the power supply unit of the facility equipment 1 itself, etc. If a positive determination is made in S203, the process proceeds to S204, where the DC-DC converter 2 of the facility equipment 1 itself is controlled to cause the DC power of the DC power supply system L2 to flow into the facility equipment 1 itself. The flowed-in power is consumed by the regenerative resistor. This reduces the DC voltage of the DC power supply system L2.

[0051] If a negative determination is made in S203, this control ends. At this time, if no facility equipment 1 other than the facility equipment 1 can consume the regenerative power, the DC voltage of the DC power supply system L2 will be high, which is undesirable from a safety standpoint. Therefore, in such a case, it is preferable to control the AC-DC converter 101 to flow the power of the DC power supply system L2 to the external power supply system L1.

[0052] <Modification of Power Supply Control 2> A modified example of the above-described power supply control will be described with reference to Fig. 7. Fig. 7 shows a schematic configuration of facility equipment 1 in which this modified example is performed. The facility equipment 1 shown in Fig. 7 differs from the facility equipment shown in Fig. 3 in that a power storage device 71 is connected to the first power supply line 3, but the other configurations are essentially the same between the two, and therefore detailed description will be omitted. Then, a predetermined program is repeatedly executed at predetermined intervals in the control unit 70, thereby realizing power supply control.

[0053] In the power supply control of this modification, if a positive determination is made in the process of S202 shown in Fig. 6, that is, if the DC voltage of the DC power supply system L2 exceeds a predetermined second voltage due to regenerative power generated by the other facility equipment 1, instead of the process of S203, it is determined whether the state of charge (SOC) of the power storage device 71 is in a state where it is possible to store power. For example, if the charge amount of the power storage device 71 is 70% or less of the maximum charge state (full charge state) of the power storage device 71, it is determined that it is possible to store power. If it is determined that it is possible to store power, the DC-DC converter 2 of the facility equipment 1 is controlled so that DC power from the DC power supply system L2 flows into the facility equipment 1, and power is charged into the power storage device 71 from the first power supply line 3.

[0054] As a further modification, the power storage device 71 may be arranged by being connected to each of the load power supply paths 12, 22, 32 in each of the power supply units 10, 20, 30, or to any one of the load power supply paths 12, 22, 32. Even when the facility equipment 1 is configured in this manner, the facility equipment 1 can recover regenerative power generated in other facility equipment 1. Furthermore, by distributing the power storage devices 71 among the power supply units 10, 20, 30, it is possible to recover a relatively large amount of regenerative power while keeping the capacity of the power storage device 71 small.

[0055] <Anomaly detection control> Control relating to abnormality detection during power supply when a power supply unit is provided in the facility device 1 as described above will be described with reference to Fig. 8. The abnormality detection control shown in Fig. 8 is realized by repeatedly executing a predetermined program at predetermined intervals in the control unit 70.

[0056] First, in S301, in the facility equipment 1, the converted power by the DC-DC converter 2, and the converted power by the DC-DC converters 11, 21, 31 and inverter devices 13, 23, 33 in each of the power supply units 10, 20, 30 are calculated.

[0057] Next, in S302, an abnormality detection is performed for each power supply unit based on the converted power calculated in S301. For example, in the power supply unit 10, If the difference between the converted power of inverter 11 and the sum of the converted powers of inverter devices 13a to 13f exceeds a predetermined threshold, it can be determined that a power loss (abnormality) has occurred in the supply path within the power supply unit. Similar determinations can be made for other power supply units 20 and 30.

[0058] Next, in S303, abnormality detection is performed for the multiple motors to which power is supplied by each power supply unit. For example, in power supply unit 10, if the difference between the total converted power of inverter devices 13a-13f mounted therein and the total power consumption consumed to drive motors 14a-14f exceeds a predetermined threshold, it can be determined that an abnormality causing power loss has occurred in one of motors 14a-14f. The total power consumption can be calculated according to the drive pattern of motors 14a-14f, taking into account the inertia, friction, etc. of the driven objects connected to the output shafts of motors 14a-14f.

[0059] Next, in S304, an abnormality in the power supply in the facility equipment 1 is detected based on the converted power calculated in S301. For example, if the difference between the converted power of the DC-DC converter 2 and the sum of the converted power in each of the power supply units 10, 20, and 30 (i.e., the sum of the converted power of the inverter devices 13, 23, and 33) exceeds a predetermined threshold, it can be determined that a power loss (abnormality) has occurred in the supply path within the facility equipment 1. Alternatively, if the difference between the converted power of the DC-DC converter 2 and the sum of the converted power of each of the DC-DC converters 11, 21, and 31 in each of the power supply units 10, 20, and 30 exceeds a predetermined threshold, it can be determined that a power loss (abnormality) has occurred in the supply path within the facility equipment 1.

[0060] If an abnormality is detected in the power supply unit, motor, or facility equipment 1 in S302, S303, or S304, the user is notified of the abnormality in S305. This notification can be sent to an information processing device (computer, mobile terminal, etc.) owned by the user. Note that, because DC power flows through each of the DC power supply system L2, first power supply path 3, and load power supply path 12 formed in the facility equipment 1, sufficient information for detecting the abnormality can be obtained even if the period for calculating the converted power is relatively short. This greatly contributes to prompt abnormality detection.

[0061] <Appendix 1> A power supply system formed in a predetermined device (1) that receives power from an external power supply system (L2), a first power supply path (3) formed so as to be able to supply power to a plurality of load devices within the predetermined device (1); a first power converter (2) configured to receive power from the power supply system (L2), convert the power, and output first power to the first power supply path (3); A power supply system comprising:

[0062] <Appendix 2> A power supply unit (10) is included in a power supply system formed in a predetermined device (1) that has a plurality of load devices (14) and receives power from an external DC power supply system (L2), and converts input DC power to supply load power to each of the plurality of load devices (14), The power supply unit (10) a power converter (11) that converts the input DC power and outputs a predetermined DC power; a load power supply line (12) through which the predetermined DC power is output; a plurality of power supply devices (13) connected to the load power supply line (12) for converting the input predetermined DC power into load power for each of a plurality of load devices (14) and supplying the converted power; and, Equipped with a connection relationship between the plurality of power supply devices (13) and the load power supply path (12) is determined to be a predetermined relationship; Power supply unit. [Explanation of symbols]

[0063] 1: Equipment 2: DC-DC converter 3: 1st power supply path 10, 20, 30: Power supply unit 11, 21, 31: DC-DC converter 12, 22, 32: Load power supply path 13, 23, 33: Inverter device 14, 24, 34: Motor 70: Control unit 71: Power storage device

Claims

1. A power supply system formed in a predetermined device that receives power from an external power supply system, a first power supply path formed so as to be able to supply power to a plurality of load devices within the predetermined device; a first power converter configured to receive power from the power supply system, convert the power, and output first power to the first power supply path; a power supply unit including: a second power converter connected to the first power supply path and configured to convert the first power and output second power; a load power supply path configured independently from the first power supply path and from which the second power is output; and a plurality of power supply devices connected to the load power supply path and converting the input second power into load power for each of the plurality of load devices and supplying the converted second power, wherein a connection relationship of the plurality of power supply devices to the load power supply path is determined to be a predetermined relationship; Equipped with the power supply system includes a plurality of the power supply units, the second power converters included in the plurality of power supply units are daisy-chain connected via the first power supply path; Power supply system.

2. A power supply system formed in a predetermined device that receives power from an external power supply system, a first power supply path formed so as to be able to supply power to a plurality of load devices within the predetermined device; a first power converter configured to receive power from the power supply system, convert the power, and output first power to the first power supply path; a power supply unit including: a second power converter connected to the first power supply path and configured to convert the first power and output second power; a load power supply path configured independently from the first power supply path and from which the second power is output; and a plurality of power supply devices connected to the load power supply path and converting the input second power into load power for each of the plurality of load devices and supplying the converted second power, wherein a connection relationship of the plurality of power supply devices to the load power supply path is determined to be a predetermined relationship; Equipped with the power supply system includes a plurality of the power supply units, The power supply device is an inverter device, When regenerative power is generated in one of the plurality of power supply units by a regenerative operation of the load device corresponding to one of the plurality of power supply devices included in the one power supply unit, the regenerative power is consumed by another power supply unit of the plurality of power supply units via the first power supply path. Power supply system.

3. the external power supply system is a DC power system that supplies DC power, the first power converter is configured to receive DC power from the power supply system, convert the DC power, and output the first power, which is DC power, to the first power supply path; the second power converter is configured to convert the first power and output the second power, which is DC power, to the load power supply path; The power supply system according to claim 1 or 2.

4. the first power converter is configured to be able to input power in which a predetermined first parameter characterizing a form of power in the power supply system has a first fluctuation range; The power supply system according to any one of claims 1 to 3.

5. the second power converter is configured to allow input of power in which a predetermined second parameter characterizing a form of power in the first power supply path has a second fluctuation range; The power supply system according to any one of claims 1 to 4.

6. The power supply device is an inverter device, When regenerative power is generated by a regenerative operation of one of the load devices corresponding to any of the plurality of power supply devices, the regenerative power is consumed by a power running operation of a load device other than the one of the load devices via the load power supply path. The power supply system according to claim 1 or 2.

7. when a predetermined first parameter characterizing a form of power in the first power supply path due to the regenerative power generated in the one power supply unit exceeds a first threshold, the regenerative power is caused to flow to the power supply system by the first power converter. The power supply system according to claim 2 .

8. a unit abnormality detection unit that detects an abnormality related to power supply in the power supply unit based on the converted power in the second power converter and the converted power in the plurality of power supply devices; The power supply system according to claim 1 or 2.

9. a load device abnormality detection unit that detects an abnormality in the plurality of load devices based on converted power in the plurality of power supply devices and power consumption consumed for driving the plurality of load devices to which power is supplied from the plurality of power supply devices; The power supply system according to claim 1 or 2.

10. further comprising a device abnormality detection unit that detects an abnormality related to power supply in the predetermined device based on the converted power in the first power converter and the converted power in the plurality of power supply devices, or based on the converted power in the first power converter and the converted power in the second power converter. The power supply system according to claim 1 or 2.

11. a device other than the predetermined device is connected to the power supply system for supplying power to the other device; When regenerative power generated by the other device flows into the power supply system and a predetermined second parameter characterizing the form of power in the power supply system exceeds a second threshold, power conversion is performed via the first power converter of the predetermined device. The power supply system according to claim 3 .

12. further comprising a power storage device connected to the first power supply path or the load power supply path and capable of storing and discharging electricity; When the regenerative power is generated in the other device, the DC power converted by the first power converter and supplied to the first power supply path or the load power supply path is stored in the power storage device. The power supply system according to claim 11.

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