JP2020076371A - Control unit and pump device - Google Patents

Abstract

To provide a control unit and a pump device capable of appropriately controlling retry operation of a variable speed control device when the same is stopped by a protective function.SOLUTION: A control unit of a pump device performs variable speed control of at least one electrically driven pump with at least one variable speed control device. When the variable speed control device undergoes a protective stop, the control unit determines whether or not to allow retry operation of the variable speed control device to be performed on the basis of a trip factor causing the protective stop and an operation state of the pump device when the variable speed control device undergoes the protective stop.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a control unit and a pump device.

  Conventionally, as a pump device, there is known a device that supplies electric power to an electric motor of a pump through an inverter, which is an example of a variable speed controller, to operate the pump at a variable speed. In general, such an inverter detects an uncontrollable condition (also called a trip) when various sensor information is out of a specified value range in order to protect the inverter itself or other devices connected to the inverter, and is operating. If so, it has a protection function to stop the operation.

  The control unit that controls the pump device performs the retry operation of the inverter when the trip of the inverter is confirmed. In the pump device described in Patent Document 1, it is determined whether the retry operation of the inverter is possible based on the operating state of the pump when the trip of the inverter is confirmed. In addition, in the pump device described in Patent Document 2, the smaller the discharge flow rate of the pump, the larger the number of restarts used. With such control, the pump devices described in Patent Documents 1 and 2 try to avoid stopping the inverter and the pump as much as possible.

Patent No. 1914725 Specification Japanese Patent No. 2702952

  The trip of the inverter is caused by various causes such as an overcurrent or an overload acting on the inverter or an input voltage of the inverter being out of a predetermined range. Further, such an inverter trip may be due to a temporary cause caused by the operating state of the pump. However, in the conventional pump device, since the inverter determines the retry operation and sets the number of restarts regardless of the cause of the trip, the retry operation may not be performed even in the recoverable state. On the contrary, when the pump device has a problem that cannot be restored, it is also necessary to surely stop without performing the retry operation. In particular, if retry operation is repeated with the power circuit of the inverter broken, excessive current and voltage will be generated in the power circuit, which may burn the circuit and cause a serious accident. It is necessary to avoid the retry operation in the closed state and stop it surely.

  The present invention has been made in view of the above circumstances, and proposes a control unit and a pump device that can appropriately perform a retry operation of a variable speed controller when the variable speed controller is stopped by a protection function. Is one of the purposes.

According to one embodiment, there is proposed a control unit of a pump device for performing variable speed control of at least one electric motor driven pump by at least one variable speed controller, and when the variable speed controller is protected and stopped. The control unit determines whether to permit or prohibit the retry operation of the variable speed controller based on the trip cause that is the cause of the protection stop and the trip-time operation state at the time of the protection stop. According to this control unit, when the variable speed controller is protected and stopped, the retry operation of the variable speed controller can be appropriately performed based on the cause of the trip and the operating state at the time of the trip.

It is a figure which shows in a schematic structure of the water supply apparatus as an example of a pump apparatus. It is a figure which shows an example of a structure of the motor pump and the inverter apparatus in the water supply apparatus of FIG. It is a figure for demonstrating an example of communication between a control part and an inverter device. It is a flowchart which shows an example of the control processing at the time of an inverter trip performed by the control part of a water supply apparatus. It is a flow chart which shows an example of control processing at the time of an inverter trip performed by an inverter control part. It is a figure which shows an example of a relationship of a trip cause, a driving state at the time of a trip, and determination of permission / prohibition of retry operation. It is a figure which shows an example of the cause of a trip, the driving | running state at the time of a trip, and the retry upper limit frequency. It is a figure which shows an example of the relationship between the cause of a trip and reset of the number of retry operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in the drawings, the same or corresponding components are denoted by the same reference numerals, and duplicate description will be omitted.

  FIG. 1 is a diagram schematically showing the configuration of a water supply device as an example of a pump device. The pump device according to the present embodiment is used as a water supply device 10 for supplying water to a building such as a house, a condominium, an office building, a commercial facility, a factory, or a school. However, the pump device is not limited to one that supplies tap water or tap water to the building, and for example, a pump device such as a fire extinguishing pump device that supplies water to a fire extinguishing facility such as a sprinkler, or sewage for carrying dirty water or miscellaneous wastewater. It may be used in various usage modes such as a pump device. In FIG. 1, the water supply device 10 is used in a direct connection water supply system, and the suction port of the water supply device 10 is connected to a water pipe (water main) 104 via an introduction pipe 105. However, the water supply device 10 may be used in a water tank system in which the suction port of the water supply device 10 supplies water supplied from the water pipe 104 through a water tank not shown. A water supply pipe 107 is connected to the outlet of the water supply device 10, and the water supply pipe 107 communicates with a water supply plug (for example, a faucet) of each building. The water supply device 10 increases the pressure of water from the water pipe 104 (or the water receiving tank) and supplies the water to each water faucet of the building.

  As shown in FIG. 1, the water supply device 10 of the present embodiment includes two motor pumps 40a and 40b, inverter devices 50a and 50b that are examples of a variable speed controller, and a control unit 60. Each of the motor pumps 40a and 40b includes a pump 44 having an impeller (not shown) and a motor 42 that is an example of an electric motor that supplies power to the pump 44. In this embodiment, two motor pumps 40a and 40b are provided, but one motor pump or three or more motor pumps may be provided.

  A backflow prevention device 25 is provided on the upstream side (suction side) of the pump 44. In the present embodiment, the backflow prevention device 25 is provided in the introduction pipe 105 connected to the suction port of the water supply device 10, and prevents the backflow of water from the water supply device 10 to the water pipe 104. A pressure sensor 21 is provided on the upstream side of the backflow prevention device 25. The pressure sensor 21 is a pressure measuring device for measuring the suction pressure of the pump 44 (water supply device 10).

A check valve 23, a flow switch 24, a pressure sensor 26, and a pressure tank 28 are provided on the downstream side (discharge side) of the pump 44. In the example shown in FIG. 1, two sets of a pump 44, a check valve 23, and a flow switch 24 are provided, and these are provided in parallel. By providing a plurality of pumps 44, when some of the pumps 44 cannot be operated, water supply is continued by the other pumps 44 that can be operated to avoid water interruption as much as possible.

  The check valve 23 is provided in the discharge pipe 32 connected to the discharge port of the pump 44, and prevents the reverse flow of water when the pump 44 stops. A flow switch 24 is provided on the downstream side (secondary side) of the check valve 23. The flow switch 24 is a flow rate detector that detects that the flow rate of the water flowing through the discharge pipe 32 has decreased to a predetermined value, that is, an excessively small amount of water (small amount of water). Further, a pressure sensor 26 and a pressure tank 28 are provided in the water supply pipe 107 to which the plurality of discharge pipes 32 are integrated and connected. The pressure sensor 26 is a pressure measuring device for measuring the discharge pressure of the pump 44 (water supply device 10). The pressure tank 28 is a pressure holder for holding the discharge pressure while the pump 44 is stopped.

  The inverter devices 50a and 50b control the current flowing through the motor 42 based on the control command from the control unit 60. As an example, the inverter devices 50a and 50b calculate the command frequency based on the target rotation speed of the pump 44 (for example, PID control) and minimize the difference between the command frequency and the actual frequency of the motor 42. Generate a PWM signal.

  The controller 60 of the water supply device 10 is provided to control the automatic water supply by the pump 44. The control unit 60 of this embodiment includes a storage unit (control memory) 66, a calculation unit 67, and an I / O unit 68. Further, the operation panel 70 and the external communication unit 73 may be provided.

  As the storage unit 66 of the control unit 60, a ROM, a HDD, an EEPROM, a FeRAM, a nonvolatile memory such as a flash memory, or a volatile memory such as a RAM is used. The storage unit 66 stores various data relating to the water supply device 10, such as a control program for controlling the water supply device 10, device information, set value information, history information, and abnormality information.

  The set value information is information whose value is changed mainly depending on the usage environment of the water supply device 10, the device configuration, the water supply method, and the like, and is information that can be changed by an operator through external input. In the present embodiment, the setting value information can be set by inputting through the setting unit 71, the external communication unit 73, or the I / O unit 68 (external input terminal (not shown)). In the present embodiment, the input through the setting unit 71, the input through the external communication unit 73, and the signal input to the external input terminal of the I / O unit 68 are referred to as “external input”. The device information may also be changeable by external input.

  The abnormality information is information regarding an abnormality in the water supply device 10. The abnormality information includes various alarms (inverter trip, discharge pressure abnormal decrease, various sensor abnormalities, etc.) and information regarding abnormalities (inflow pressure decrease, water tank full water drought, etc.). Further, the abnormality information may include information for prompting replacement or maintenance of the inverter devices 50a and 50b. Further, the abnormality information also includes a trip cause that is a cause of the protection function when the protection function that stops the protection of the inverter devices 50a and 50b occurs.

  The history information is information regarding various history of the water supply device 10. The history information may include cumulative operating time and cumulative driving frequency of the motor pumps 40a and 40b, alarm history in the water supply device 10, various communication history, various operation history, and the like. The history information includes a trip cause, which is a cause of the protection function when the protection function of the inverter devices 50a and 50b is stopped, and operation information of the water supply device 10 when the protection function occurs. It is good to be.

The operation information is information indicating the current state of the water supply device 10, and is updated at a constant cycle (several tens of mSEC to several seconds). The operation information is the current motor pumps 40a, 4
0b each operating or stopped state, rotation speed of the motor pumps 40a, 40b, current value flowing in the motor driving the motor pumps 40a, 40b, input voltage of the water supply device 10, suction pressure of the motor pumps 40a, 40b, motor pump It includes the discharge pressures of 40a and 40b, the target pressure SV, and the like. It may also include values of various sensors input to the I / O unit 68, output signals, and the like. The operation information includes the trip cause that is the cause of the protection function when the protection function of the inverter devices 50a and 50b is stopped and the operating state of the motor pumps 40a and 40b when the protection function occurs. Is included.

  A CPU, for example, is used as the calculation unit 67 of the control unit 60. The calculation unit 67 performs a calculation for controlling each device constituting the water supply device 10 based on a control program and various data stored in the storage unit 66, and a signal input from the I / O unit 68. To do. The arithmetic unit 67 also controls communication in the external communication unit 73, the I / O unit 68, and the like, and display and operation in the operation panel 70. The calculation result of the calculation unit 67 is stored in the storage unit 66 and is also output to the I / O unit 68 and the external communication unit 73.

  A port or the like is used as the I / O unit 68. The I / O unit 68 receives detection signals from various sensors (not shown) and sends them to the arithmetic unit 67. Further, the I / O unit 68 includes a communication unit 68a, and the communication unit 68a and each of the inverter devices 50a and 50b are connected to each other by wired or wireless communication such as serial communication such as RS422, RS232C, RS485 or packet communication such as Ethernet. It is connected. The inverter devices 50a and 50b are configured to be communicable with the control unit 60 using a communication protocol common to each maker such as Modbus, TCP / IP, or a maker-specific communication protocol. Then, the inverter devices 50a and 50b and the control unit 60 share various data stored in the storage unit 66 by communication.

  The operation panel 70 is a GUI (Graphical User Interface) capable of displaying and changing various data stored in the storage unit 66 via the calculation unit 67. Specifically, the operation panel 70 displays device information and setting value information and changes settings, displays abnormality information and resets, and displays operation information. The operation panel 70 of the present embodiment includes a setting unit 71 and a display unit 72. The control unit 60 and the operation panel 70 may be separate substrates. In this case, the control unit 60 and the operation panel 70 may be connected by serial communication, a cable such as a signal line, or wirelessly. When the control unit 60 and the operation panel 70 are separate substrates, the operation panel 70 may be installed in a place apart from the water supply device 10 (for example, a manager's room). Further, the operation panel 70 may include a CPU, and the CPU may control the display operation or control the communication with the control unit 60 and an external device. Further, the operation panel 70 may be provided with a buzzer (not shown) for making a warning sound or an operation sound.

  The setting unit 71 of the operation panel 70 is an information input unit of the control unit 60, and various inputs such as operation / stop of automatic water supply in the water supply device 10, alarm reset, and setting change of various data by an external operation of the user. Used to perform an operation. The setting unit 71 may include an operation button, a touch panel, or the like (not shown). The information input by the external operation through the setting unit 71 is stored in the storage unit 66. The display unit 72 of the operation panel 70 functions as a user interface and is configured to display various data stored in the storage unit 66. In preparation for the case where the water supply device 10 is installed in an environment with a lot of electrical noise such as a machine room or a pump room, a 7-segment LED or indicator lamp that is more resistant to electrical noise than a liquid crystal display and a touch panel is used as the display unit 72. In addition, an indicator constituted by a mechanical push button or the like may be used. As a result, the water supply device 10 can be installed even in an environment with a lot of electrical noise. However, the display unit 72 is not limited to a display that is resistant to electrical noise, and a dot matrix liquid crystal display or the like may be used.

  The external communication unit 73 is configured to be able to communicate with the external device (external terminal) 90 by wire communication or wireless communication. As the wireless communication in the external communication unit 73, for example, a technology of near field communication (NFC: Near Field Communication) can be used. Also, wireless communication of any method such as Bluetooth (registered trademark) and Wi-Fi can be used. Here, the NFC is advantageous in that the communication can be completed only by bringing the control unit 60 and the external device 90 close to each other. As wired communication, for example, the control unit 60 may be provided with an external connection terminal such as a USB (Universal Serial Bus), and the external device 90 may be connected to the external connection terminal to perform communication, or RS422, RS232C. , RS485 or the like may be used.

  Note that all the functions of the operation panel 70 described above may be implemented by the external device 90. By doing this, even if the water supply device 10 is installed in a place where it is difficult to operate (for example, the operation panel 70 is around the feet of the operator), it becomes easy to perform operations such as checking the state of the water supply device 10 and changing the set value information. ..

FIG. 2 is a diagram showing an example of the configuration of the motor pump and the inverter device in the water supply device 10 of FIG. As shown in FIG. 2, the water supply device 10 includes switches SW1 and SW2 that shut off the electric power from the commercial power supply 100 input to the inverter devices 50a and 50b, respectively. The switches SW1 and SW2 are, for example, earth leakage circuit breakers (ELB: Earth Leakage Circuit Breaker).
It is preferable that the ON state (energized state) and the OFF state (power cutoff state) are individually switched by the output of the control unit 60 and manually when the leakage is detected. In the present embodiment, SW1 and SW2 are in the ON state when the inverter devices 50a and 50b are in an abnormal state or in a normal time, which is not the time of maintenance, and the inverter devices 50a and 50b are supplied with power from the commercial power supply 100. Then, the inverter devices 50a and 50b convert the AC power from the commercial power source 100 into AC power having a desired frequency and supply the AC power to the motors 42 of the motor pumps 40a and 40b. In the present embodiment, one inverter device is provided for each pump, but one inverter device may be provided for two or more motor pumps. In addition, in the present embodiment, the inverter device 50a and the inverter device 50b have the same configuration, and duplicate description will be omitted below.

  The inverter device 50a includes an inverter circuit 570 and an inverter control unit 560 including a communication unit 561 capable of communicating with the control unit 60.

  The inverter circuit 570 is an inverter circuit that generates an AC voltage based on the PWM signal from the inverter control unit 560 and applies the AC voltage to the motor 42. The inverter circuit 570 includes a converter unit 570a, a DC voltage smoothing circuit 570b, an inverter unit 570c, and a gate driver 570d.

  Converter unit 570a has a rectifier circuit configured by a diode or the like for converting a three-phase AC voltage supplied from commercial power supply 100 into a DC voltage. The DC voltage smoothing circuit 570b includes a capacitor and smoothes the DC voltage converted by the converter unit 570a. The inverter unit 570c has a power element such as an IGBT (insulated gate bipolar transistor) and a plurality of diodes connected in parallel to the power element, and has three phases from the DC voltage smoothed by the DC voltage smoothing circuit 570b. It is configured to generate an alternating voltage. The gate driver 570d generates a gate drive signal for switching each power element of the inverter unit 570c based on the PWM signal from the inverter control unit 560.

The inverter device 50a is a voltage sensor 5 that measures the voltage input from the commercial power supply 100.
70e. Specifically, the inverter circuit 570 preferably includes a voltage sensor 570e that measures the voltage of the DC voltage smoothing circuit 570b, and the voltage sensor 570e is preferably connected to the inverter control unit 560. Then, the measured value of the voltage obtained by the voltage sensor 570e is input to the inverter control unit 560. Hereinafter, the voltage input to the inverter control unit 560 is referred to as the input voltage of the inverter device 50a.

  The inverter control unit 560 includes a control memory 562, a communication unit 561, and a calculation unit (not shown). The inverter control unit 560 may further include an I / O unit (not shown) and an operation panel (not shown). A CPU, for example, is used as the arithmetic unit of the inverter control unit 560. The arithmetic unit controls each device constituting the inverter device 50a based on a control program and various data stored in the control memory 562, and a signal input from an I / O unit (not shown). Performs calculations, etc. As the I / O unit of the inverter control unit 560, a port for inputting / outputting digital signals and analog signals, various communication ports, and the like are used. The I / O unit receives detection signals from various sensors (not shown) and sends them to the arithmetic unit. As the control memory 562 (storage unit), a ROM, a HDD, an EEPROM, a FeRAM, a nonvolatile memory such as a flash memory, or a volatile memory such as a RAM is used. The control memory 562 stores a control program of the inverter circuit 570 executed by the arithmetic unit and information about the inverter device 50a.

  The information stored in the control memory 562 includes operation information, device information, control parameters, history information, trip information, and the like. The operation information stored in the control memory 562 includes information indicating that protection is stopped, current, voltage, accelerating, decelerating, command frequency, current frequency, and other operating conditions. The history information stored in the control memory 562 may include a history of trip occurrences and a history of trip causes. Further, the control memory 562 may store the operating state when the trip occurs as history information.

  The inverter control unit 560 stores a plurality of control parameters for controlling the inverter circuit 570 in the control memory 562. For example, the inverter control unit 560 has a gain, an integration time, a differentiation time, etc. used in the PID calculation as control parameters. Further, the inverter control unit 560 has a carrier frequency for performing a switching operation as a control parameter. The inverter control unit 560 has a control parameter capable of setting the V / f characteristic, and based on the set V / f characteristic, the voltage output to the motor 42 and the frequency have a substantially direct proportional relationship “V / f”. Control ". Here, when the frequency output to the motor 42 is low, the influence of the voltage drop becomes large and the torque output from the motor 42 decreases. Therefore, the inverter control unit 560 performs torque boost voltage control that raises the output voltage in the low frequency region in order to compensate for the influence. Inverter control unit 560 has a control parameter for setting this torque boost voltage. Further, the inverter control unit 560 has the maximum frequency output by the inverter device 50a as a control parameter. Further, the inverter control unit 560 has acceleration time and deceleration time as control parameters. When accelerating / decelerating the motor 42, the inverter control unit 560 limits increase / decrease in the frequency of the motor 42 based on the acceleration time / deceleration time. Here, the acceleration time may be, for example, the time for the frequency of the motor 42 to reach a predetermined rotation speed (for example, the maximum output frequency) from zero. The deceleration time may be, for example, the time for the frequency of the motor 42 to reach zero from a predetermined rotation speed (for example, maximum output frequency). That is, the acceleration time and the deceleration time are control parameters that can suppress the acceleration / deceleration of the motor 42 as these times are longer.

It is preferable that a voltage sensor 571 and a current sensor 572 arranged on the secondary side of the inverter circuit 570 are further connected to the inverter control unit 560. The voltage and current measurement values obtained by the voltage sensor 571 and the current sensor 572 are input to the inverter control unit 560. Inverter control unit 560 generates a PWM signal for minimizing the difference between the measured value of the fed-back current and the command current. When the inverter control unit 560 can predict the voltage and current on the secondary side of the inverter circuit 570, the voltage sensor 571 and the current sensor 572 may not be provided. The inverter control unit 560 preferably has a current control function and suppresses the current flowing through the motor 42 at the stall current value. The inverter control unit 560 may detect the overload of the motor 42 by an electronic thermal function based on the current obtained by the current sensor 572. The inverter control unit 560 may have valid / invalid of the electronic thermal function, an operation level, and the like as control parameters.

  In the example shown in FIG. 2, the pump 44, the motor 42, and the inverter circuit 570 are provided with temperature sensors 80, 81, and 82 for measuring the temperatures thereof, respectively. When the measured value of the temperature of at least one of the temperature sensors 80, 81, and 82 reaches a predetermined upper limit value, the control unit 60 or the inverter control unit 560 lowers the rotation speed of the pump 44 from that during steady operation. A command may be issued to the inverter circuit 570 so that the pump 44 is stopped or the pump 44 is stopped.

  The inverter devices 50a and 50b have various protection functions to stop protection in order to protect each device in the water supply device from a serious accident such as burnout. Specifically, the protection stop by the inverter control unit 560 is stopped when the motor 42 is operating, and continued when it is stopped. In addition, the following examples can be given as trip causes that cause the protection function and the protection stop.

  The inverter control unit 560 has a protection function of stopping protection when the output current becomes equal to or higher than a predetermined threshold value. The protection function is also called “overcurrent trip”, and the cause of trip is overcurrent. Specifically, the inverter control unit 560 suspends protection when the measured value of the current sensor 572 or the output current value of the inverter control unit 560 becomes equal to or greater than a predetermined current specified value.

  The inverter control unit 560 has a protection function of stopping protection when it is determined that the load of the motor 42 is equal to or higher than the specified load value. Hereinafter, the protection function is also referred to as “overload trip”, and the cause of trip is overload. Specifically, the inverter control unit 560 stops the protection when it determines an overload by an electronic thermal function using the value of the output current of the current sensor 572 or the inverter control unit 560 or a thermal not shown.

  The inverter control unit 560 has a protection function of stopping protection when the input voltage becomes equal to or higher than a predetermined threshold value. Hereinafter, the protection function is also referred to as “input overvoltage trip”, and the cause of trip is overvoltage. Specifically, the inverter control unit 560 stops protection when the voltage of the voltage sensor 570e becomes equal to or higher than the first voltage specified value. As one embodiment, the first voltage specified value may be a value that becomes an “input overvoltage trip” when the commercial power supply 100 has a voltage fluctuation that is higher than the rated voltage by 10% or more.

  The inverter control unit 560 has a protection function of stopping protection when the input voltage becomes equal to or lower than a predetermined threshold value. Hereinafter, the protection function is also referred to as “input undervoltage trip”, and the cause of trip is the input undervoltage. Specifically, the inverter control unit 560 suspends protection when the voltage of the voltage sensor 570e becomes equal to or lower than the second voltage specified value. It should be noted that the second voltage regulation value is set to a value smaller than the first voltage regulation value, and in one embodiment, the second voltage regulation value is when the commercial power supply 100 has a voltage fluctuation that is lower than the rated voltage by 10% or more. It is recommended to set the value to “Input undervoltage trip”.

Further, the inverter control unit 560 has a protection function of stopping the protection when the measured values of the temperature sensors 80, 81, 82 become equal to or higher than the temperature specified value. Hereinafter, the protection function is also referred to as “heating trip”, and the cause of trip is heating.

  The inverter control unit 560 has a protection function of stopping protection when a predetermined communication abnormality with various sensors or a predetermined communication abnormality with the control unit 60 is detected. Hereinafter, the protection function is also referred to as "communication error trip", and the cause of the trip is communication abnormality.

  It should be noted that the inverter control unit 560 is not limited to having all the above-mentioned protection functions as the protection functions of the inverter devices 50a and 50b, and may have at least a part of them. In addition, the inverter control unit 560, when the protection is stopped by the protection function, causes the trip (for example, overcurrent, overload, input overvoltage, input undervoltage, communication error, etc.) and trip-time operating state (frequency command value, frequency). Current value, current value, input voltage value, acceleration, deceleration, low speed, and stop) are preferably stored.

  Further, as shown in FIG. 2, the inverter controller 560 is further connected to a flow switch 24 that detects the small amount of water of the pump 44 and pressure sensors 21 and 26 that measure the discharge pressure of the pump 44. Good. That is, the detection values of the flow switch 24 and the pressure sensors 21 and 26 may be input to the control unit 60 and / or the inverter control unit 560 of the inverter devices 50a and 50b. When the detection values of the flow switch 24 and the pressure sensors 21 and 26 are input to either the control unit 60 or the inverter control unit 560, the detection values are shared by the control unit 60 and the inverter devices 50a and 50b by communication. To be done.

  The communication unit 68a of the control unit 60 of the present embodiment and the inverter devices 50a and 50b are connected by a communication line 68b. As an example, RS485 serial communication is performed by a master / slave system such as Modbus. To do. Further, the master side of the master / slave system is the control unit 60, the slave side is the inverter devices 50a and 50b, various inquiries are transmitted from the control unit 60, and the inverter devices 50a and 50b receiving the inquiries are only for inquiries to themselves. It is recommended to send a response, and otherwise leave it unresponsive. The inverter devices 50a and 50b corresponding to the inquiry destinations send a response (normal response or abnormal response) based on the content of the inquiry. Further, the communication unit 68a designates one of the inverter devices 50a and 50b as an inquiry destination, and reads information stored in various storage units 562 and current values such as frequency values and current values. The inverter device 50a, 50b corresponding to the inquiry destination transmits the information, the information stored in the storage unit 562, the actual frequency value and the current value, or the abnormal response as the normal response. In addition, the slave inverter devices 50a and 50b do not respond to the inquiry when they receive the inquiry of writing and the inquiry of reading and do not correspond to the inquiry destination. When the control unit 60 receives the above-described abnormal response or determines that neither of the inverter devices 50a and 50b responds to the inquiry, a communication error with the inverter devices 50a and 50b occurs. to decide. The control unit 60 and the inverter devices 50a and 50b may communicate with each other in a master-slave system in which one of the inverter devices 50a and 50b is on the master side and the control unit 60 is on the slave side. In this case, the control unit 60 may determine that a communication error has occurred when determining that communication has been interrupted for a predetermined time or longer. It should be noted that the determination of the communication error may be always performed while the control unit 60 and the inverter devices 50a and 50b are communicating.

3A and 3B are diagrams for explaining an example of communication between the control unit 60 and the inverter devices 50a and 50b. The control unit 60 of the present embodiment sequentially transmits a control command such as the rotation speed of the pump 44 and a command for reading the information of the inverter devices 50a and 50b to each of the inverter devices 50a and 50b. As an example, the control unit 60, as a control command to the pump 44, includes a control signal including a rotation speed command (hereinafter, also referred to as “first control command”).
, And a control signal including an instruction to operate / stop the pump 44 (hereinafter, also referred to as “second control instruction”). The control unit 60 also transmits a read command for reading the information of the inverter devices 50a and 50b. The read command may also include information indicating that the inverter devices 50a and 50b have tripped (protection stopped). Further, the control unit 60 transmits a state writing command for writing various data (input values of various sensors such as pressure values and operating states) stored in the storage unit 66 to the inverter devices 50a and 50b.

In the example shown in FIG. 3A, the communication order is shown when neither of the inverter devices 50a and 50b has caused a trip (protection stop). The control unit 60 makes inquiries in the following order. (Hereinafter, the inverter device 50a and the motor pump 40a are also referred to as No. 1 pump, and the inverter device 50b and the motor pump 40b are also referred to as No. 2 pump hereinafter.)
(1) No. 1st control command (2) No. No. 1 of the first control command (3) to the two pumps. Second control command (4) No. 1 to pump 1 2nd control command (5) No. Read command to pump 1 (6) No. 2 Read command (7) No. Status writing command to pump 1 (8) No. The state writing command control unit 60 for the two pumps repeats the transmission of the inquiries (1) to (8) described above. As an example, the inquiry of each command signal from the control unit 60 is performed every predetermined period (for example, 50 msec) or when the response of the inverter devices 50a and 50b due to the inquiry of each command signal is received, the next command signal is inquired. Switch to send.

  Note that in the example shown in FIG. Two pumps were started as starting pumps. Therefore, No. “0 Hz” is transmitted as the first control command to one pump and “stop” is transmitted as the second control command in this order, and the inverter device 50a that receives these control commands sets the pump 44 to the stopped state. In addition, No. An inquiry about "FHz" is sent as the first control command to the two pumps and an "operation" is sent as the second control command, and the inverter device 50b receiving this inquiry operates the pump 44 at the FHz. When the water supply device 10 performs automatic water supply described later, “FHz” is the rotation speed determined based on the discharge pressure.

  After that, as the water supply amount increases, the control unit 60 sets No. 1 at t1. No. 1 since the addition of 1 pump. “FHz” is transmitted as an inquiry for the first control command to one pump, and “run” is transmitted as the second control command, and the inverter device 50a receiving these control commands operates the pump 44 at FHz. In addition, No. An inquiry about "FHz" is sent as the first control command to the two pumps and an "operation" is sent as the second control command, and the inverter device 50b receiving this inquiry operates the pump 44 at the FHz.

  In the example illustrated in FIG. 3B, the communication order when the inverter device 50a is protected and stopped during operation is shown. The above (5) No. When the control unit 60, which has received the response to the read command to the 1 pump, determines that the response includes the trip signal, the control unit 60 reads and writes the cause of the trip and the operating state at the time of the trip (at the time of trip). An inquiry of an interrupt command) is transmitted to the inverter device 50a (No. 1 pump). Then, the process returns to the normal transmission order (6). By such interrupt communication, the control unit 60 and the inverter device 50a or / and 50b, when the protective function occurs, cause the trip that is the cause of the protective function and the operation when the protective function occurs. Status and can be quickly obtained. The trip-time interrupt command may be composed of a plurality of inquiries.

The control unit 60 sends the first control command, the second control command, the read control command, and the state write command to the No. 1 pump and No. 1 The present invention is not limited to sequentially transmitting to the two pumps, and other command signals may be transmitted from the control unit 60 to the inverter devices 50a and 50b instead of or in addition to these signals. In addition, No. 1 pump and No. 1 The inquiry about the interrupt command at the time of trip to the 2nd pump may be transmitted periodically regardless of whether a trip occurs or not (5) No. Read command to pump 1 and / or (6) No. It may be included in the read command to the two pumps.

  In the water supply device 10, the control unit 60 performs the following automatic water supply (automatic operation control of the pump 44). When the discharge pressure drops to a predetermined starting pressure while the pump 44 is stopped, the control unit 60 determines that the starting condition of the pump 44 is satisfied, and the control unit 60 starts at least one of the pumps 44. .. As the starting condition of the pump 44, various predetermined conditions may be used instead of or in addition to the discharge pressure reaching the starting pressure or less. During the operation of the pump 44, the rotational speed control of the pump 44 such as the estimated end pressure constant control or the target pressure constant control is performed by the set pressure (set pressure). Specifically, in the case of the constant estimated end pressure control, the target pressure (SV) is set using the rotation speed of the pump 44 and the target pressure control curve, and in the case of the constant target pressure control, the set pressure is the target pressure (SV). And In addition, the discharge pressure is the present pressure (PV). Then, based on the difference (pressure deviation) between SV and PV, PI calculation using the proportional gain Gp and the integral gain Gi, or PID calculation using the proportional gain Gp, the integral gain Gi, and the differential gain Gd. Then, the target rotation speed (FHz) of the pump 44 is set. Further, when there are a plurality of pumps 44 as in the present embodiment, the control unit 60 also controls the number of pumps according to the amount of water by the number of pumps that can be started simultaneously (the number of pumps in parallel operation). The PID calculation is omitted if the pressure deviation is within a predetermined pressure deviation threshold value GAP (for example, ± 1%), so that stable pressure control is realized.

  When the amount of water used in the building is reduced during water supply by the pump 44, the flow switch 24 detects an excessively small amount of water and sends a detection signal to the control unit 60 (small amount of water state). The control unit 60 receives this detection signal and issues a command to the pump 44 to increase the rotational speed of the pump 44 until the discharge pressure reaches a predetermined stop pressure, and after the pressure is accumulated in the pressure tank 28, the pump 44 is stopped (small Stop water flow). When water is used again in the building after the pump 44 has stopped a small amount of water, the discharge pressure drops below the starting pressure and the pump 44 starts (small restart). When there are a plurality of pumps 44 as in the present embodiment, it is preferable to rotate the pump 44 to be started to prevent water from staying in the pump 44. In addition, as a method of detecting the amount of underwater, other means such as light load when the current value of the motor 42 is equal to or less than a predetermined threshold value or comparison of discharge pressure and cutoff pressure is used without using the flow switch 24. May be.

  Next, the operation of the water supply device 10 when the inverter devices 50a and 50b are protected and stopped will be described. FIG. 4 is a flowchart showing an example of a trip time control process executed by the control unit of the water supply device. In the example shown in FIG. 4, when the pump is protection stopped, the control unit 60 (control unit) causes the protection stop (trip cause) and the operation state of the pump device 10 at the time of protection stop (trip operation state). ), The permission or prohibition of the retry operation of the inverter devices 50a and 50b is determined. The water supply device 10 executes the retry operation with permission of the retry operation. Further, the control unit 60 (control unit) may set the retry operation upper limit number CN based on the trip cause that is the cause of the protection stop. In this case, the control unit 60 (control unit) executes the retry operation until the number of retry operations reaches the retry operation upper limit number CN. When the retry operation is prohibited, the retry operation is not executed and the protection stop is continued regardless of the retry operation upper limit number CN. In the following, for simplification of description, a case where the inverter device 50a is protection stopped will be described, but the same applies when the inverter device 50b is protection stopped.

The process of FIG. 4 is started when the inverter device 50a stops protection. In particular,
As one embodiment, it is started when the control unit 60 receives information indicating that protection has been stopped from the inverter device 50a. As an example, referring to FIG. 3B, (5) No. from the control unit 60 transmitted immediately before t2. The inverter device 50a that has received the read command for one pump transmits an information signal, which is information indicating that protection is stopped, to the control device 60, and the control unit 60 that has received the information signal is shown in FIG. Start processing.

  When the trip time control processing is started, the control unit 60 first transmits an "trip time interrupt command" to the inverter device 50a in order to acquire the cause of the trip, and causes the inverter device 50a to trip and the operation state during trip. Is acquired (S12). In the inverter device 50a, there are cases where the protection function is activated and the protection is stopped due to a cause that occurs in an extremely short time, such as an instantaneous overcurrent. On the other hand, as described above, the control unit 60 periodically transmits the read command for acquiring the information of the inverter device 50a to the inverter device 50a. Therefore, the protective function of the inverter device 50a is restored before the control unit 60 transmits an inquiry for obtaining information from the inverter device 50a after the protective function of the inverter device 50a occurs (for example, after several hundred msec). There is a case. Therefore, even if the inverter device 50a receives the read command and transmits its own information to the control unit 60, the control unit 60 may not be able to recognize the cause of the trip based on the transmitted information. Therefore, when the control unit 60 receives the information including the protection stop from the inverter device 50a, the control unit 60 transmits an inquiry for reading the trip information at an interrupt to determine the cause of the protection stop. It may be acquired from 50a. The inverter device 50a, which has received the inquiry about the trip information read command, causes the protection function as a response (for example, overcurrent, overload, overvoltage, input undervoltage, communication error, etc.) and operating state (current, voltage, acceleration). (Medium, decelerating, command frequency, current frequency, etc.) is transmitted to the control unit 60. As a result, the control unit 60 can properly grasp the cause of trip and the operating state during trip of the inverter device 50a.

  If the history information stored in the control memory 562 includes the cause of the trip, the information acquired by the interrupt transmission of the “trip-time interrupt command” may be the cause of the trip stored in the history information. By doing so, even when the protection function is restored at the timing of interrupt transmission, the cause of trip can be identified.

  Subsequently, the control unit 60 permits / prohibits the retry operation of the inverter device 50a based on the acquired trip cause and the operating state when the protection stop occurs (hereinafter, referred to as “trip operating state”). A determination is made (S14). Here, as the operation state during trip, information predetermined for each cause of trip is used.

  The control unit 60 may read the time when the protection stop occurs together with the cause of the trip from the inverter device 50a and set the operating state of the pump 44 at the time as the trip-time operating state. The control unit 60 reads from the inverter device 50a the operating state (current, voltage, accelerating, decelerating, command frequency, current frequency, etc.) of the inverter device 50a at the time when the protection stop occurred together with the cause of the trip, and the read information. May be the operating state during trip. Further, the control unit 60 may set the operation state of the pump 44 when the information indicating that the inverter device 50a is in the protection stop state to the trip operation state. Further, the control unit 60 trips the operating state of the pump 44 when the discharge pressure sharply decreases because the discharge pressure sharply decreases due to the stop of the pump 44 when the inverter device 50a in operation stops protection. It may be set to the hourly operating state. The control unit 60 may set the trip-time operating state by combining the operating state when the protection stop is received from the inverter device 50a and the operating state of the pump 44 when the protection stop information is received.

Hereinafter, the determination of permission / prohibition of the retry operation of the inverter device 50a in S14 will be described. As shown in FIG. 6, the determination of permission / prohibition of the retry operation of the inverter device 50a is made based on the cause of the trip and the operating state during the trip. FIG. 6 is a diagram showing an example of the relationship between the cause of trip, the operating state during trip, and the determination of permission / prohibition of retry operation. The control unit 60 permits the retry operation when it is determined that the protection stop is due to the operating state of the pump, and prohibits the retry operation when it is determined that the power circuit of the inverter device 50a may be broken.

  As shown in (A) of FIG. 6, when the cause of the trip is an overcurrent of the inverter device 50a and the operating state at the time of trip is accelerating the pump 44, the control unit 60 causes the inverter device 50a to perform the retry operation. to approve. This is because the current during the acceleration of the pump 44 becomes larger than that during the deceleration and the constant speed operation.

  Specifically, when the change in the rotation speed of the pump 44 is equal to or higher than a predetermined rotation speed change threshold, the control unit 60 may allow the retry operation of the inverter device 50a while accelerating the pump 44. More specifically, when the amount of increase in the rotation speed of the pump 44 per unit time is larger than the predetermined first threshold value, the control unit 60 determines that the trip-time operating state is accelerating. This is based on the fact that the overcurrent generated in the inverter device 50a is considered to be due to the sudden increase in the load of the pump 44. Here, the first threshold may be, for example, in the vicinity of the amount of increase per unit time due to the acceleration time that is the control parameter of the inverter device 50a.

  As the rotation speed of the pump 44, a rotation speed based on a measurement value of a speed detector (not shown) or the like may be used, or a rotation speed command from the control unit 60 may be used. Further, as the rotation speed of the pump 44, a value received from the inverter device 50a may be used.

  The control unit 60 may determine that the pump 44 is accelerating based on the difference between the target pressure of the pump 44 and the discharge pressure instead of or in addition to the change in the rotation speed. That is, the control unit 60 determines that the acceleration is in progress when the difference between the target pressure and the discharge pressure is equal to or more than a predetermined pressure threshold during the operation of the pump 44 (target pressure> discharge pressure). In the automatic water supply control, the control unit 60 controls the pump 44 at a variable speed based on the pressure deviation which is the difference between the target pressure and the discharge pressure. Therefore, if the pressure deviation is greater than or equal to the predetermined pressure threshold, the rotation speed of the pump 44 is accelerating.

  Note that the control unit 60 may receive a signal during acceleration from the inverter device 50a through communication. The inverter device 50a determines and stores an operating state during acceleration, deceleration, or constant speed based on the change in the output frequency and / or the current frequency, and stores the operating state. 1 Response to read command to pump. The inverter device 50a may send the operation state stored when the protection function occurs to the control unit 60 as a response to the inquiry of the trip information read command, or indicate that the inverter device 50a has stopped protection. It is advisable to use the signals received before and after receiving the information indicating whether the vehicle is accelerating or not, as the trip-time operating state.

  On the other hand, when an overcurrent trip occurs, the control unit 60 prohibits the retry operation when the operating state of the pump 44 when the protection function occurs is in deceleration or constant speed. Specifically, the control unit 60, when the change in the rotation speed of the pump 44 is less than a predetermined rotation speed change threshold, or when the difference between the target pressure of the pump 44 and the discharge pressure is less than the predetermined pressure threshold. In addition, the retry operation of the inverter device 50a may be prohibited. The control unit 60 may receive a signal during deceleration or constant speed from the inverter device 50a through communication.

Further, as shown in FIG. 6B, when the inverter device 50a has an overcurrent trip and is in the steady operation after the completion of the pump start, the control unit 60 permits the retry operation of the inverter device 50a. You may. This is because the discharge pressure of the pump 44 is proportional to the square of the rotation speed and the shaft power of the pump 44 is proportional to the cube of the rotation speed. Therefore, the higher the discharge pressure of the pump 44, the more it flows to the inverter device 50a. This is because the current becomes large. When the predetermined pressure has been reached since the pump 44 was started, and / or when a predetermined time has passed since the pump was started, the steady operation is performed after completion of the start. The controller 60 may permit the retry operation of the inverter device 50a if an overcurrent trip occurs during steady operation after completion of startup. Specifically, the control unit 60 controls the pump 44 after the discharge pressure reaches a predetermined pressure (as an example, a pressure value equal to or higher than the starting pressure) after the pump 44 starts. After a predetermined time (for example, a time equal to or longer than the acceleration time which is the control parameter of the inverter device 50a) has elapsed, it is determined that the pump 44 has been started and is in a steady operation state (during steady operation after completion of pump startup). To do. The control unit 60 may permit the retry operation of the inverter device 50a when the pump 44 is in the steady operation after the completion of the start when the protection stop due to the overcurrent occurs. This is because the amount of water in the pump 44 is proportional to the rotation speed, and therefore the current due to the load on the pump 44 is small during startup when the rotation speed is lower than during steady operation. Therefore, if an overcurrent trip frequently occurs during startup, the inverter circuit 570 may be broken. Further, if there is a problem with the set value of the inverter device 50a and an overcurrent trip occurs, it is necessary to readjust the set value. On the other hand, when the pump 44 is in the steady operation after the completion of the start-up, the overcurrent generated in the inverter device 50a is caused by a temporary cause such as the foreign material biting of the pump 44 and the load fluctuation in addition to the load by the carrier liquid. Based on what is considered to be something. On the other hand, the control unit 60 may prohibit the retry operation of the inverter device 50a when the pump 44 is being started when the overcurrent trip occurs.

  As an example, the predetermined pressure for the control unit 60 to determine that the engine is in steady operation after completion of startup is preferably a pressure value equal to or higher than the startup pressure. Since the pump 44 is started at a pressure equal to or lower than the starting pressure when the small amount of water is stopped, it is advisable that the period during which the pump 44 is discharged at a pressure equal to or higher than the starting pressure and the pressure is restored is being started. Further, the predetermined time after the pump 44 is started for the control unit 60 to determine that the steady operation is performed after the completion of the start is, for example, a time equal to or longer than the acceleration time which is the control parameter of the inverter device 50a. Since the inverter device 50a rises from 0 Hz to the highest frequency over the acceleration time, it can be assumed that the time required to recover the pressure once dropped at the time of start up to the target pressure is near the acceleration time.

  As shown in (C) of FIG. 6, when the inverter device 50a causes an overload trip, the control unit 60 permits the retry operation when the operation state at the time of trip is the pump heavy load operation. Specifically, the control unit 60 determines that the pump is under heavy load operation when the pump 44 is operating at a predetermined rotation speed or higher. When the inverter device 50a causes an overload trip and the rotation speed of the pump 44 instructed by the control unit 60 is equal to or higher than a predetermined rotation speed threshold, the control unit 60 permits the retry operation of the inverter device 50a. Good. This is because the amount of water in the pump 44 is proportional to the rotation speed, so that the overload generated in the inverter device 50a or the pump 44 consumes a large amount of water that is equal to or more than the designed amount of water at the time of design, or foreign matter is caught in the pump 44. This is based on the fact that it is considered to be due to a temporary external factor that is resolved by temporarily stopping. For example, the rotation speed threshold value may be a rotation speed corresponding to 90% or more of the maximum frequency which is the control parameter of the inverter device 50a. On the other hand, the control unit 60 may prohibit the retry operation of the inverter device 50a when the rotation speed of the pump 44 is less than a predetermined rotation speed threshold when an overload trip occurs.

In addition to or instead of determining that the pump 44 is in operation under a heavy load when the pump 44 is operating at a predetermined rotation speed or higher, the control unit 60 determines that the discharge pressure is a predetermined threshold value or less and a predetermined value. It is advisable to judge that the vehicle is in a heavy load state when it is continuously operated for a time ΔT or more. In this heavy load state, the discharge pressure is assumed to be equal to or lower than the target pressure even though the amount of water used at the water supply destination is large and the rotation speed is the maximum rotation speed. As an example, the threshold value of the discharge pressure for determining the heavy load state is a value less than the target pressure (for example, 98% or less of the target pressure), and the predetermined time ΔT is a control parameter of the inverter device 50a. It is good to be more than an hour. This is because the pump device 10 is selected with a certain margin with respect to the planned water amount. If the amount of water used is less than or equal to the designed water amount at the time of design, the discharge pressure will be almost the same value as the target pressure except during the transitional period when the amount of water used changes and the pressure fluctuates. Therefore, an overload trip that occurs in a heavy load state in which the discharge pressure is continuously operated at the target pressure or less causes a large stoppage of the pump 44 due to consumption of a large amount of water that is greater than or equal to the designed water amount at the time of design, or the inclusion of foreign matter. It is considered that this is due to a temporary external factor that is resolved by doing so.

  When the inverter device 50a causes an input overvoltage trip as shown in FIG. 6D, the inverter device 50a permits the retry operation when the operation state at the time of trip is pump deceleration. Specifically, when the decrease in the rotation speed of the pump 44 is equal to or higher than a predetermined rotation speed decrease threshold value, it is determined that the deceleration is being performed, and the control unit 60 may permit the retry operation of the inverter device 50a. This is based on the fact that the cause of the overvoltage generated in the inverter device 50a is considered to be due to temporary regeneration during deceleration of the pump 44. In particular, when the pump 44 in operation stops due to a small amount of water stop, pump disconnection, or the like, the inverter device 50a receiving the “stop command” from the control unit 60 sets the frequency of the motor 42 to 0 Hz based on the deceleration time. Since it slows down, temporary regeneration is likely to occur. Therefore, if an input overvoltage trip occurs during deceleration after the control unit 60 commands the inverter device 50a to "stop", the retry operation of the inverter device 50a may be permitted. On the other hand, when an input overvoltage trip occurs, the control unit 60 causes some failure in the input voltage of the inverter device 50a or the inverter circuit 570 when the decrease in the rotation speed of the pump 44 is less than the predetermined rotation speed reduction threshold value. Since it is considered that the inverter device 50a is being operated, the retry operation of the inverter device 50a is prohibited. The control unit 60 may determine the retry based on the signal during deceleration received from the inverter device 50a.

  As shown in FIG. 6E, when the inverter device 50a has an input undervoltage trip and the operating state at the time of trip is the pump light load state, the control unit 60 permits the retry operation of the inverter device 50a. To do. Specifically, in the pump light load state, the pump 44 is stopped or the rotation speed of the pump 44 is equal to or lower than the light load rotation threshold value. Further, when the input undervoltage is eliminated within a predetermined time, control unit 60 may permit the retry operation of inverter device 50a. This is based on the fact that the input undervoltage generated in the inverter device 50a is considered to be due to a temporary external factor such as a momentary power failure (a momentary blackout) of the commercial power supply 100. It should be noted that the light load rotation threshold value may be the same as the minimum rotation speed of the pump 44 in the automatic water supply control, for example.

The pump light load state is when the water supply amount in the pump 44 is small (for example, 0.03 m ³ / min or less). For example, the current value of the flow switch 24 and the motor 42 are compared with a threshold value, and the discharge is performed. When a small amount of water is detected by detecting means such as comparison of pressure and shutoff pressure, it is advisable to set the pump to a light load state.

  As shown in (F) of FIG. 6, when the inverter device 50a causes an input undervoltage trip, if the operating state during trip is such that the pressure deviation is within a predetermined first pressure deviation threshold value, the control unit 60 Permits the retry operation of the inverter device 50a. Specifically, when the pressure deviation is within a predetermined first pressure deviation threshold value, the steady operation is performed after the completion of the pump start, and the operation is performed in a stable state where the pressure fluctuation is small. Therefore, it is based on the fact that the input undervoltage generated in the inverter device 50a is considered to be due to a temporary external factor such as a momentary power failure (a momentary blackout). The first pressure deviation threshold value may be set to a value equivalent to the pressure deviation dead zone GAP in the PID calculation.

As shown in (G) of FIG. 6, when the inverter device 50a causes an input undervoltage trip, if the operating state during trip is a state in which the pressure deviation is equal to or more than a predetermined second pressure deviation threshold value, the control unit 60 Permits the retry operation of the inverter device 50a. Specifically, it is assumed that the pump 44 is operating in a state where the pump 44 discharges due to an excessive amount of water and the pressure is insufficient when the state where the pressure deviation is equal to or larger than the predetermined second pressure deviation threshold value continues. .. Therefore, it is considered that the input undervoltage generated in the inverter device 50a is considered to be due to a temporary external factor such as a momentary voltage drop due to an increase in power supply load due to an excessive flow rate. The second pressure deviation threshold value is a value larger than the first pressure deviation threshold value.

  Further, as shown in (H) of FIG. 6, when the input undervoltage trip is resolved within a predetermined time (for example, several milliseconds to several seconds) after the input undervoltage trip occurs, the control unit 60 May permit the retry operation of the inverter device 50a. This is based on the fact that it is considered to be due to a temporary external factor such as a momentary power failure (temporary interruption) of the commercial power source 100. On the other hand, the control unit 60 determines that the input undervoltage trip does not occur due to an external factor when the input undervoltage does not disappear even after a predetermined time when the protection stop due to the input undervoltage occurs and the inverter 60 determines that the input undervoltage trip has not occurred. The retry operation of the device 50a may be prohibited.

  Further, as shown in (I) of FIG. 6, when the protection stop other than the trip causes shown in (A) to (H) occurs, the retry operation may be performed with a predetermined number of retries.

  As described above, in the water supply device 10 of the present embodiment, when the inverter device 50a is stopped by the protection function by the process of S14, the retry operation of the inverter device 50a is performed based on the trip cause and the trip-time operating state. By appropriately determining permission / prohibition of (1), it is possible to avoid the retry operation in a state where a serious accident may occur and to continue supplying water in an appropriate state. In addition to the conditions described above, the control unit 60 may determine permission / prohibition of the retry operation of the inverter device 50a based on the cause of the trip and the operation state during the trip. In addition, the control unit 60 may permit the retry operation of the inverter device 50a for a predetermined trip cause such as protection stop due to a communication error, regardless of the operation state during trip. Further, the threshold value used for determining permission / prohibition of the retry operation may be settable by an external input.

  Returning to the description of FIG. 4, when the control unit 60 determines that the retry operation of the inverter device 50a is prohibited (S16: No), the control unit 60 determines that the inverter device 50a cannot be operated without performing the retry operation (S30), and the present processing is performed. finish. As described above, by making the inverter device 50a inoperable without performing the retry operation of the inverter device 50a, a problem occurs in the inverter device 50a, the pump 44, or the like, which may lead to a serious accident such as burnout. It is possible to prevent the retry operation from being performed in this state.

  In addition, when a plurality of pumps 44 are provided like the water supply apparatus 10 of the present embodiment, it is advisable to continue the water supply by using the other pump 44 of the pumps 44 that are disabled. When the operation of the inverter device 50a is disabled, the corresponding pump 44 may not be operated. Further, particularly when the motor 42 is an induction motor, the commercial power supply 100 may be directly connected to the motor 42 to operate / stop the pump 44 at a fixed speed. Further, the control unit 60 may issue a warning when the operation of the inverter device 50a is disabled. The alarm issued by the control unit 60 is, for example, by displaying on the display unit 72, issuing an alarm by a buzzer (not shown), or by transmitting a predetermined signal from the external communication unit 73 or the I / O unit 68 to the outside. It should be done.

  When determining that the retry operation of the inverter device 50a is permitted (S16: Yes), the control unit 60 determines the retry operation upper limit number CN (hereinafter, also simply referred to as “upper limit number CN”) of the inverter device 50a based on the cause of the trip. Set (S18).

The setting of the upper limit number CN will be described below. As shown in FIG. 7, the retry upper limit number C
N is determined based on the cause of trip. The retry upper limit number CN may be determined based on the retry operation performed in S26, in addition to the cause of the trip.

  As shown in FIGS. 7A and 7B, when the cause of trip is an overcurrent, the control unit 60 sets CN1 or CN2 as the upper limit number of times CN by the operation at the time of retry executed in S22. In this embodiment, CN1 and CN2 have the same value (for example, value CN1 = value CN2 = value 4). As one embodiment, CN1 and CN2 may have different values, and if there are further different retry operations, the upper limit number CN may be set for each retry operation.

  As shown in FIG. 7C, when the cause of trip is overload, the control unit 60 sets CN3 (for example, the value CN3 = value 4) as the upper limit number of times CN. In the present embodiment, when the cause of trip is an overload, there is only one retry operation performed in S22. However, when there are multiple retry operations, the upper limit number CN is set for each retry operation. May be.

  As shown in FIG. 7D, when the trip cause is the input overvoltage, the control unit 60 sets CN4 (for example, the value CN4 = value 6) as the upper limit number CN. In the present embodiment, when the cause of trip is the input overvoltage, the number of operations at the time of retry executed in S22 is one. However, when there are a plurality of operations at the time of retry, the upper limit number CN is set for each operation at the time of retry. May be.

  As shown in FIGS. 7E and 7F, when the cause of the trip is an input undervoltage, the control unit 60 sets CN5 or CN6 as the upper limit number of times CN by the operation at the time of retry executed in S22. In this embodiment, CN5 and CN6 have the same value (value CN5 = value CN6 = value 6). As one embodiment, CN5 and CN6 may have different values, and if there is a retry operation, the upper limit number CN may be set for each retry operation.

  As shown in FIG. 7 (G), when the inverter device 50a has a protection stop due to another trip cause (A) to (F), such as a protection stop due to a communication error, the control unit 60 causes the control unit 60 to output a value CN0 (for example, The value CN0 = value 5) is set as the upper limit number of times CN.

  When the control unit 60 determines that the retry is prohibited in S14 in the present embodiment, S16 is No and the retry operation is not executed. In one embodiment, when the retry is prohibited in S14, the retry operation may be executed with the value Cn smaller than the upper limit number CN when the retry is permitted as the upper limit number. In that case, the determination in S16 of FIG. 4 is omitted. In other words, in one embodiment, CN (first upper limit number) is set as the retry operation upper limit number for the motor pumps 40a, 40b connected to the inverter devices 50a, 50b for which the retry operation is permitted, and the retry operation is performed. For the motor pumps 40a and 40b connected to the inverter devices 50a and 50b whose operation is prohibited, Cn (second upper limit number) smaller than CN may be set as the retry operation upper limit number.

  Here, as shown in FIG. 7, it is preferable to divide into groups 1 to 4 in the order in which it is determined that there is a risk of causing a serious accident for each trip cause, and set the upper limit number of times for each group. In this grouping, groups may be divided according to trip causes that can be determined to be protection stopped due to a temporary factor. In this embodiment, the overcurrent / overload is set to group 1, and the retry upper limit number is set to, for example, 4. The overvoltage / input undervoltage is set to group 3, and the upper limit number of retries is set to, for example, 6. For other causes of trip, the group 2 is set, and the upper limit number of retries is set to, for example, 5. In this way, setting the upper limit number of times for each group facilitates setting change. Further, a common retry operation number Cr may be used in the same group.

Here, when the protection stop caused by overcurrent or overload occurs, the control unit 60 sets a smaller upper limit number CN as compared with the protection stop caused by overvoltage or undervoltage (abnormal input voltage). Is preferably set. This is because an overcurrent or an overload is accompanied by a temperature rise and may lead to a serious accident such as a burnout of the inverter device 50a or the motor 42 as compared with an abnormal input voltage.

  In this way, the control unit 60 may set the retry operation upper limit number CN based on the trip cause as well as the trip operation state when the inverter device 50a is protection stopped. Based on the cause of the trip and the operating state at the time of trip, the control unit 60 may assume that the protection stop of the inverter device 50a is due to a relatively mild factor, or the trip may be a temporary operating state of the pump 44 or an external state. When it is assumed that it depends on a factor, a large value may be set as the upper limit number CN.

  In this way, by the process of S18, in the water supply device 10 of the present embodiment, when the inverter device 50a is protected and stopped, the retry operation upper limit number CN can be appropriately set based on the cause of the trip. Note that the control unit 60 may set the upper limit number of times CN based on the cause of the trip, even under conditions other than the above conditions. The values CN1 to CN5 set as the upper limit number CN may be settable by external input. As a result, the upper limit number CN can be changed depending on the capacity of the pump 44, the usage environment of the water supply device 10, and the like.

  Next, the control unit 60 compares the retry operation number Cr with the upper limit number CN (S20). Here, the number of times of retry operation Cr is a counter that is incremented by 1 each time a retry operation is performed, and is assumed to be reset to a value of 0 as an initial value when the water supply device 10 is powered on. Further, it is preferable that a plurality of retry operation numbers Cr are provided for each cause of trip and each operation state during trip. Specifically, as shown in FIG. 7, the control unit 60 has a plurality of retry count counters Cr0 to Cr6 for each trip cause and each trip-time operating state. As a result, appropriate retry operation can be performed even when protection stops having different trip causes occur consecutively.

  When the number of times of retry operation Cr is less than the upper limit number of times CN (S20: Yes), the control unit 60 waits until the inverter device 50a becomes in a state where retry operation is possible (S22). Here, the state in which the inverter device 50a can perform the retry operation is, for example, that a predetermined period has elapsed since the inverter device 50a was protection stopped last time, and the start condition in the automatic water supply control of the pump 44 (for example, small stop restart). Conditions and conditions for adding pumps, etc.).

  When the control unit 60 determines that the retry operation of the inverter device 50a is possible (S22: Yes), the retry operation count Cr is incremented by 1 (S24), and the retry operation of the inverter device 50a is executed. Yes (S26). Here, in S24, the control unit 60 counts the number of retry operations Cr0 to Cr6 corresponding to the cause of the trip and the operating state during the trip. In the present embodiment, a plurality of retry operation times Cr are provided for each trip cause and each trip-time operating state. In one embodiment, a plurality of retry operation numbers Cr may be provided for each trip cause or each trip-time operating state, or only one may be provided regardless of the trip cause or trip-time operating state. By having a plurality of retry number counters, it is possible to perform the retry operation at the retry number suitable for the cause of the trip and the operating state during the trip.

During the retry operation in S26, the control unit 60 transmits a trip cancellation command to the inverter device 50a, and then transmits a driving command to operate the pump 44. Here, as shown in “Operation during Retry” in FIGS. 7A to 7G, during retry operation, control for retry operation different from normal time (when the retry operation number Cr is 0) is performed. Use parameters. As a result, it is possible to appropriately perform the retry operation while avoiding the protection function caused by the operating state of the pump.

  As shown in (A) of FIG. 7, when the cause of trip is an overcurrent, the control unit 60 limits the upper limit value of the output frequency more than in the normal case. As a result, the flow rate of the pump 44 can be limited and the load of the carrier liquid can be reduced.

  As shown in (B) of FIG. 7, when the cause of trip is an overcurrent, it is preferable to set an acceleration time longer than the normal time as a control parameter for the retry operation. As a result, the acceleration of the pump 44 becomes gentle, and the current can be limited.

  As shown in (C) of FIG. 7, when the cause of trip is overload, the control unit 60 limits the upper limit value of the output frequency more than in the normal case. As a result, the flow rate of the pump 44 can be limited and the load of the carrier liquid can be reduced.

  As shown in (D) of FIG. 7, when the cause of the trip is an input overvoltage, the control unit 60 may set a deceleration time that is longer than the normal time as a control parameter for the retry operation. As a result, the deceleration of the pump 44 becomes slower and the electromotive voltage can be limited.

  As shown in (E) of FIG. 7, when the cause of trip is the input undervoltage, the control unit 60 causes the protection stop for a longer time than other protection stops. In the voltage smoothing circuit 570b, the chargeable capacity decreases due to deterioration over time. By lengthening the protection stop time, it is possible to suppress the occurrence of an input undervoltage trip due to the shortage of the charging capacity of the DC voltage smoothing circuit 570b.

  As shown in (F) of FIG. 7, when the cause of trip is an input undervoltage, the control unit 60 limits the upper limit value of the output frequency more than in the normal case. As a result, the current flowing through the motor 42 can be limited, and the occurrence of an input undervoltage trip due to a shortage of the capacity of the DC voltage smoothing circuit 570b due to deterioration over time can be suppressed.

  Further, the control unit 60 may change the setting of the control parameter for the retry operation based on the trip-time operation state in addition to the trip cause. Specifically, as an example, if the cause of trip is an overcurrent and the operating state during trip is pump acceleration ((A) of FIG. 6), the acceleration time is lengthened ((B) of FIG. 7). If the cause of the trip is overcurrent and the operating state at the time of trip is steady operation ((B) of FIG. 6), the upper limit value of the output frequency is limited ((A) of FIG. 7). If the cause of the trip is overload and the operating state at the time of trip is heavy load operation ((C) of FIG. 6), the upper limit value of the output frequency is limited ((C) of FIG. 7). In this way, the control unit 60 may change the setting of the control parameter based on the cause of the trip and the operating state during the trip.

  After executing the retry operation in S26 of FIG. 4, the control unit 60 determines whether the inverter device 50a has returned. When the control unit 60 determines that the inverter device 50a has returned (S28: Yes), this processing ends. Here, the determination as to whether or not the inverter device 50a has returned is made based on a predetermined condition, for example, after the retry operation of the inverter device 50a is performed, the operation is continued without protection stop for a predetermined period. Just do it.

As shown in FIG. 8, whether or not the retry operation number Cr is cleared to 0 after the inverter device 50a is restored may be determined based on different criteria depending on the cause of the trip. As an example, when a protection stop due to an overcurrent trip or an overload trip occurs, the control unit 60 may perform a retry operation of the inverter device 50a and, if no abnormality has occurred for a predetermined period of time, the inverter device 50a. It is preferable to clear the number of retry operations Cr after the completion of the return. Further, when the protection stop due to the input overvoltage trip or the input undervoltage trip occurs, the control unit 60 does not cause any abnormality until the pump 44 is stopped next after the retry operation of the inverter device 50a is executed. First, it is preferable to clear the retry operation number Cr after the return of the inverter device 50a is completed. Further, when the protection stop due to the communication error occurs, the control unit 60 completes the recovery of the inverter device 50a and clears the retry operation number Cr when the communication is normally performed without the communication error occurring for a certain period. Good to do.

  In the present embodiment, a clear condition for the number of times of retry operation Cr is provided for each group determined in the order in which it is determined that a serious accident may occur depending on the cause of the trip. In one embodiment, a condition for clearing the retry operation number Cr may be set for each cause of the trip, or a condition for clearing the retry operation number Cr may be set for each operation at the time of retry. In this way, the retry operation can be properly performed by making the clear conditions for the trip that may lead to a serious accident more severe than the clear conditions for other trips.

  When it is not determined in S28 of FIG. 4 that the inverter device 50a has recovered due to protection stop of the inverter device 50a again during the retry operation of the inverter device 50a (S28: No), the control unit 60 again performs the process of S20. Return to. When the retry operation of the inverter device 50a is executed a plurality of times and the retry operation number Cr reaches the upper limit number CN or more (S20: No), the control unit 60 determines that the inverter device 50a cannot be operated (operation is prohibited). (S30), this process ends. As described above, in the water supply device 10 of the present embodiment, the retry operation upper limit number CN is set based on the cause of the trip, so the retry operation of the inverter device 50a can be appropriately executed.

  In the process of S22, the larger the number of retry operations Cr, the more severe the determination as to whether or not the inverter device 50a is in the retry operation possible state. For example, when the number of times of retry operation Cr is the first number of times, it is assumed that the retry operation of the inverter device 50a is executed after the first time has elapsed since the last stop of the inverter device 50a. On the other hand, when the number of times of retry operation Cr is the second number larger than the first number, the retry operation of the inverter device 50a is executed after the second time longer than the first time has elapsed since the last stop of the inverter device 50a. Good to do. This is because it is considered that the larger the retry operation number Cr of the inverter device 50a, the higher the possibility that the inverter device 50a, the motor 42, or the like has an abnormality.

  In addition, as shown in the operation at the time of retry in FIG. 7, the inverter device 50a has different control parameters for the retry operation when the retry operation is executed, which is different from the normal operation (when the retry operation number Cr is 0). Should be used. As the control parameter for the retry operation, a control parameter for the retry operation that is predetermined in the inverter device 50a may be used, or the setting may be changed to the inverter device 50a by the control unit 60 during the retry operation in S26. .. Here, when the control unit 60 changes the setting of the control parameter of the inverter device 50a during the retry operation, the inverter device 50a that receives the setting change inquiry from the control unit 60 stores the control parameter for the retry operation only in the volatile memory. Good to remember. By doing so, it is possible to suppress an increase in the number of times of writing to the nonvolatile memory in the inverter device 50a. Further, the inverter device 50a may execute the subsequent control by using the control parameter for normal time stored in the non-volatile memory when a power failure occurs during the retry and the power is restored (S28).

Further, the control unit 60 sets the control parameter for the retry operation so that the larger the retry operation number Cr, the more slowly the retry of the inverter device 50a is performed (when the retry operation number Cr is 0). You may set it. For example, the control unit 60 sets the acceleration time to the first acceleration time when the retry operation number Cr is the first number. On the other hand, the control unit 60 sets the acceleration time to the second acceleration time longer than the first acceleration time when the retry operation number Cr is the second number larger than the first number. This is based on the assumption that the larger the retry operation number Cr of the inverter device 50a, the more difficult it is to restore the inverter device 50a.

  Further, when the number of times of retry operation Cr reaches a predetermined number of times of issuance, which is smaller than the upper limit number of times CN, the control unit 60 may issue a notification to that effect. The alarm issued by the control unit 60 is, for example, by displaying on the display unit 72, issuing an alarm by a buzzer (not shown), or by transmitting a predetermined signal from the external communication unit 73 or the I / O unit 68 to the outside. It should be done. Further, when the number of times of retry operation Cr reaches the number of times of notification, the control unit 60 may store the fact as history information. By such control, even when the inverter device 50a is restored after that, the user can be prompted to replace or maintain the inverter device 50a.

  In the above-described embodiment, the control unit 60 sets the permission / prohibition of the retry operation of the inverter device 50a or the retry operation upper limit number CN. However, the present invention is not limited to such an example, and at least one of the permission / prohibition of the retry operation and the retry operation upper limit number CN may be set by the inverter control unit 560 of the inverter device 50a.

  FIG. 5 is a flowchart showing an example of inverter trip time control processing executed by the inverter control unit 560. In the example shown in FIG. 5, in the pump device 10, when the inverter devices 50a and 50b, which are variable speed controllers, stop protection, the inverter control unit 560 (control unit) instead of the control unit 60 causes the protection stop. The permission or prohibition of the retry operation of the inverter devices 50a and 50b is determined based on a certain trip cause and the operating state of the pump device 10 at the time of protection stop. Further, in the water supply device 10, after the inverter devices 50a and 50b are protected and stopped, the retry operation is executed until the number of retry operations reaches the retry operation upper limit number CN, and the inverter control unit 560 (control unit) stops protection. The retry operation upper limit number CN is set based on the cause of trip, which is the cause of.

  The process of FIG. 5 is started when the inverter device 50a stops protection. When this process is started, the inverter control unit 560 first acquires the trip-time operating state (S42). As an example, the inverter control unit 560 may acquire the trip-time operating state through communication with the control unit 60. Further, as shown in FIG. 2, the inverter control unit 560 directly reads the measured value from the sensor (in the example shown in FIG. 2, the flow switch 24 and the pressure sensors 21 and 26) that measures the operating state of the pump 44, and trips. The hourly driving state may be acquired.

  Subsequently, the inverter control unit 560 determines permission / prohibition of its own retry operation based on the cause of the trip and the operating state during the trip (S44). Further, the inverter control unit 560 sets the retry operation upper limit number CN based on the cause of the trip (S46). The processes of S44 and S46 may be performed in the same manner as the processes of S14 and S18 of FIG. Then, the inverter control unit 560 transmits the retry operation permission / prohibition determination and the retry operation upper limit number CN to the control unit 60 of the water supply device 10 (S48), and ends this processing. In this way, the same effect as that of the above-described embodiment can be obtained by the inverter control unit 560 determining whether to permit / prohibit the retry operation and set the retry operation upper limit number CN.

As described above, the control unit 60 and / or the inverter control unit 560 is a control unit of the water supply device 10 that performs variable speed control of at least one pump 44 by the inverter devices 50a and 50b that are variable speed controllers. When the shift controller is protection stopped, the control unit determines the trip cause (for example, overcurrent, overload, input overvoltage, input undervoltage, etc.) that is the cause of the protection stop, and the trip operating state at the time of protection stop. (Permitting or prohibiting retry operation of the variable speed controller based on (acceleration, steady operation, heavy load operation, deceleration, light load operation, pressure deviation of discharge pressure, trip time) of the pump 44) To judge. As a result, the water supply apparatus 10 in the recoverable state is subjected to the retry operation, and the water supply apparatus 10 in the state in which there is a risk of burnout or a serious accident can be reliably stopped without avoiding the retry operation. The control unit may determine whether to permit or prohibit the retry operation based on the cause of the trip and the operation state at the time of trip after performing the retry operation a predetermined number of times regardless of the cause of the trip.

  Further, the water supply device 10 performs a retry operation until the number of retry operations reaches the upper limit number of retry operations when the variable speed controller stops protection, and the control unit performs the retry operation based on the trip cause that is the cause of the protection stop. Set the maximum number of times. Then, the control unit counts the number of retry operations for each trip cause state and / or each trip operation state at the time of protection stop. As a result, the number of retry operations of the water supply apparatus 10 in a state in which there is a risk of burning out or a serious accident is limited as compared with the water supply apparatus 10 in a recoverable state, and an appropriate retry operation can be executed.

  Although the control unit 60 and the inverter control unit 560 share various data through communication in the above-described embodiment, the control unit 60 and the inverter control unit 66 share various data through analog signals and digital signals. Good. Further, although the inverter devices 50a and 50b have various protection functions in the above-described embodiment, the control unit 60 may have various protection functions described above. Further, the control unit 60 and the inverter control unit 560 may be arranged on the same substrate, or the control unit 60 and the inverter control unit 560 may be configured by one CPU. In that case, the one CPU is referred to as a control unit.

The embodiment described above can also be described as the following modes.
[Mode 1] According to mode 1, a control unit of a pump device is proposed in which at least one variable speed controller controls at least one electric motor driven pump at a variable speed, and the variable speed controller is protected and stopped. In this case, the control unit determines whether to permit or prohibit the retry operation of the variable speed controller based on the trip cause that is the cause of the protection stop and the trip operation state at the time of the protection stop. According to the first aspect, the control unit can appropriately perform the retry operation of the variable speed controller based on the cause of the trip and the trip-time operating state when the variable speed controller is protected and stopped.

[Mode 2] According to mode 2, in the control unit of mode 1, when the trip cause is an overcurrent of the variable speed controller and the trip-time operating state is accelerating the pump, Permits the retry operation of the variable speed controller. This is because the cause of the trip is considered to be a temporary cause caused by a large change in the load of the pump.

[Mode 3] According to mode 3, in the control unit of mode 2, the control unit determines that the acceleration is in progress when the change in the rotation speed of the pump is equal to or more than a predetermined rotation speed change threshold value.

[Mode 4] According to mode 4, in the control unit of mode 2 or 3, the pump device includes a pressure gauge for measuring the discharge pressure of the pump, and the difference between the predetermined target pressure and the discharge pressure is measured. The pump is subjected to variable speed control based on a certain pressure deviation, and the control unit determines that the acceleration is in progress when the pressure deviation is equal to or more than a predetermined pressure threshold.

[Mode 5] According to Mode 5, in the control unit of Modes 1 to 4, the pump device includes a pressure gauge for measuring a discharge pressure of the pump, and the pump starts the discharge of the pump after being started. After the pressure reaches a predetermined pressure and / or after a predetermined time has elapsed after the start, steady operation is performed after the start is completed, and the control unit causes the trip cause to be the overspeed of the variable speed controller. When the current is the current and the operation state at the time of trip is the steady operation, the retry operation of the variable speed controller is permitted. This is based on the fact that the cause of the trip is considered to be a temporary factor due to the start of the pump.

[Mode 6] According to mode 6, in the control unit of modes 1 to 5, the cause of trip is an overcurrent of the variable speed controller, and the operation state at trip is deceleration or constant speed. At this time, the control unit prohibits the retry operation of the variable speed controller.

[Mode 7] According to mode 7, in the control unit of modes 1 to 6, when the cause of the trip is an overload of the variable speed controller and the operating state at the time of trip is pump heavy load operation. The control unit permits the retry operation. This is based on the fact that the cause of the trip is considered to be a temporary factor due to the heavy load on the pump.

[Mode 8] According to mode 8, in the control unit of mode 7, the control unit determines that the heavy load operation is being performed when the rotational speed of the pump is equal to or higher than a predetermined rotational speed threshold.

[Mode 9] According to mode 9, in the control unit of mode 7 or 8, the pump device includes a pressure gauge for measuring a discharge pressure of the pump, and a difference between a predetermined target pressure and the discharge pressure. The variable speed control of the pump is performed based on the pressure deviation, and the control unit determines that the heavy load operation is in progress when the pump continuously operates at the discharge pressure equal to or lower than the target pressure for a predetermined time or more.

[Mode 10] According to mode 10, in the control unit of modes 1 to 9, when the cause of the trip is an input overvoltage of the variable speed controller and the operation state at the time of trip is during pump deceleration, The control unit permits a retry operation of the variable speed controller. This is based on the fact that the cause of trip is considered to be a temporary factor due to the deceleration of the pump.

[Mode 11] According to mode 11, in the control unit of mode 10, in the pump device, after the pump stop command, the frequency of the electric motor is reduced based on a deceleration time which is a control parameter of the variable speed controller. The pump is stopped by the deceleration control performed, and the control unit determines that the pump is being decelerated during the deceleration control.

[Mode 12] According to mode 12, in the control unit of modes 1 to 11, when the cause of trip is an input undervoltage of the variable speed controller and the operation state at trip is a pump light load state. In addition, the control unit permits the retry operation of the variable speed controller. This is based on the fact that the cause of trip is considered to be a temporary external factor.

[Mode 13] According to Mode 13, in the control unit of Mode 12, the control unit is in a state where the rotational speed of the pump in operation is lower than a predetermined rotational speed, or when the pump is stopped. It is determined that the pump is in the light load state.

[Mode 14] According to mode 14, in the control unit according to mode 12 or 13, the pump device has a small water amount detection means, and the control unit is configured to detect the small water amount by the pump light load. Judge that it is in a state.

[Mode 15] According to Mode 15, in the control unit of Modes 1 to 14, the pump device includes a pressure gauge for measuring a discharge pressure of the pump, and a difference between a predetermined target pressure and the discharge pressure. Variable speed control of the pump on the basis of the pressure deviation is, the trip cause is an input undervoltage of the variable speed controller, and the operating state at the time of trip, the pressure deviation is a predetermined first pressure deviation threshold value. When it is within the range, the control unit permits the retry operation of the variable speed controller. This is based on the fact that the cause of trip is considered to be a temporary external factor.

[Mode 16] According to mode 16, in the control unit of modes 1 to 15, the pump device includes a pressure gauge for measuring a discharge pressure of the pump, and a difference between a predetermined target pressure and the discharge pressure. Variable speed control of the pump based on the pressure deviation is, the trip cause is an input undervoltage of the variable speed controller, and the trip-time operating state is such that the pressure deviation is a predetermined second pressure deviation threshold value. In the above state, the control unit permits the retry operation of the variable speed controller. This is based on the fact that the cause of the trip is considered to be a temporary factor due to a large change in the discharge pressure of the pump.

[Mode 17] According to Mode 17, in the control unit of Modes 1 to 16, the cause of the trip is an input undervoltage of the variable speed controller, and the operating state at the time of trip is a predetermined rotational speed of the pump. In the state of being equal to or less than the light load rotation threshold value of, the retry operation of the variable speed controller is permitted. This is based on the fact that the cause of trip is considered to be a temporary external factor.

[Mode 18] According to mode 18, in the control unit of modes 1 to 17, when the cause of trip is an input undervoltage of the variable speed controller, the control unit determines that the input undervoltage is within a predetermined time. When the problem is resolved, the retry operation of the variable speed controller is permitted.

[Mode 19] According to Mode 19, in the control unit of Modes 1 to 18, the control unit is a control unit that communicates with the variable speed controller, and the control unit is configured to operate from the variable speed controller to the variable speed controller. When the information including the protection stop is received, a command for acquiring the cause of the trip is interrupt-transmitted to the variable speed controller. According to the nineteenth aspect, the control unit can properly acquire the cause of the trip.

[Mode 20] According to mode 20, in the control unit of modes 1 to 19, the control unit, when the variable speed controller is protected and stopped, performs a retry operation of the variable speed controller based on the cause of the trip. The upper limit number is set, and the control unit prohibits operation of the variable speed controller when the retry operation number of the variable speed controller reaches the retry operation upper limit number. According to the twentieth aspect, when the variable speed controller is protected and stopped, the retry operation upper limit number of times of the variable speed controller can be appropriately set based on the cause of the trip.

[Mode 21] According to Mode 21, in the control unit of Modes 1 to 20, the control unit controls the variable speed controller based on the cause of trip when the variable speed controller is protected and stopped. Is changed and the retry operation is executed. According to the twenty-first aspect, when the variable speed controller is protected and stopped, the control parameter can be appropriately set and changed based on the cause of the trip, and the retry operation can be appropriately performed.

[Mode 22] According to mode 22, the control unit according to any one of modes 1 to 21 and a pump driven by an electric motor by the at least one variable speed controller are provided, and the retry operation is permitted. A pump device in which the electric motor driven pump connected to the variable speed controller continues predetermined automatic water supply, and the electric motor driven pump connected to the variable speed controller in which the retry operation is prohibited is protected and stopped. Is proposed. According to the pump device of the twenty-second aspect, it is possible to obtain the same effects as the control unit described above.

[Mode 23] According to mode 23, there is proposed a pump device including the control unit according to any one of modes 1 to 21 and a pump driven by an electric motor by the at least one variable speed controller. Sets the first upper limit number as the retry operation upper limit number of the variable speed controller for the electric motor driven pump connected to the variable speed controller for which the retry operation is permitted, and the retry operation is For the electric motor driven pump connected to the prohibited variable speed controller, a second upper limit number less than the first upper limit number is set as the retry operation upper limit number of the variable speed controller, and the control is performed. The unit prohibits operation of the variable speed controller when the number of retry operations of the variable speed controller reaches the upper limit number of retry operations. According to the pump device of the twenty-third aspect, it is possible to obtain the same effects as the above-described control unit.

  Although the embodiments of the present invention have been described above, the above-described embodiments of the present invention are intended to facilitate understanding of the present invention and do not limit the present invention. The present invention can be modified and improved without departing from the spirit of the invention, and it goes without saying that the present invention includes equivalents thereof. Further, in the range in which at least a part of the problems described above can be solved, or in the range in which at least a part of the effect is achieved, any combination of the embodiment and the modifications is possible, and is described in the claims and the specification. It is possible to arbitrarily combine or omit the respective constituent elements.

10 ... Pump device 40a, 40b ... Motor pump 42 ... Motor (electric motor)
44 ... Pumps 50a, 50b ... Inverter device 60 ... Control unit 66 ... Storage unit 67 ... Calculation unit 68 ... I / O unit 68a ... Communication unit 70 ... Operation panel 71 ... Setting unit 72 ... Display unit 73 ... External communication unit

Claims (23)

A control unit of a pump device for variable speed control of at least one electric motor driven pump by at least one variable speed controller,
When the variable speed controller is protection stopped, the control unit retries the variable speed controller based on a trip cause that is the cause of the protection stop and a trip time operation state at the time of the protection stop. Determine whether to permit or prohibit driving,
Controller unit.   The trip cause is an overcurrent of the variable speed controller, and the control unit permits a retry operation of the variable speed controller when the operating state at the time of trip is accelerating the pump. The described control unit. The control unit determines that the change in the rotation speed of the pump is equal to or greater than a predetermined rotation speed change threshold and that the acceleration is being performed.
The control unit according to claim 2. The pump device includes a pressure gauge for measuring the discharge pressure of the pump, the pump is variable speed control based on a pressure deviation that is a difference between a predetermined target pressure and the discharge pressure,
The control unit determines that the acceleration is in progress when the pressure deviation is equal to or more than a predetermined pressure threshold value,
The control unit according to claim 2 or 3. The pump device includes a pressure gauge for measuring the discharge pressure of the pump,
The pump is in a steady operation after completion of startup when the discharge pressure of the pump reaches a predetermined pressure after starting, and / or when a predetermined time has elapsed after starting,
The control unit permits the retry operation of the variable speed controller when the cause of the trip is an overcurrent of the variable speed controller and the operation state at the time of trip is the steady operation. The control unit according to any one of 1 to 4.   The trip cause is an overcurrent of the variable speed controller, and the control unit prohibits a retry operation of the variable speed controller when the trip-time operating state is decelerating or constant speed. The control unit according to any one of items 1 to 5. The cause of the trip is an overload of the variable speed controller, and when the trip-time operating state is pump heavy load operation,
The control unit permits the retry operation,
The control unit according to any one of claims 1 to 6.   The control unit according to claim 7, wherein the control unit determines that the heavy load operation is being performed when the rotation speed of the pump is equal to or higher than a predetermined rotation speed threshold value. The pump device includes a pressure gauge that measures a discharge pressure of the pump, and controls the pump at a variable speed based on a pressure deviation that is a difference between a predetermined target pressure and the discharge pressure,
9. The control unit according to claim 7, wherein the control unit determines that the heavy load operation is in progress when the pump continuously operates at the discharge pressure equal to or lower than the target pressure for a predetermined time or more. The cause of the trip is an input overvoltage of the variable speed controller, and the control unit permits the retry operation of the variable speed controller when the operating state at the time of trip is pump deceleration. 9. The control unit according to any one of 9. In the pump device, after the pump stop command, the pump is stopped by deceleration control in which the frequency of the electric motor is decelerated based on a deceleration time that is a control parameter of the variable speed controller,
The control unit determines that the pump is being decelerated during the deceleration control.
The control unit according to claim 10.   The trip cause is an input undervoltage of the variable speed controller, and the control unit permits the retry operation of the variable speed controller when the trip-time operation state is a pump light load state. Item 12. The control unit according to any one of items 1 to 11.   The control unit determines that the pump is in the light load state when the rotational speed of the pump in operation is lower than a predetermined rotational speed or when the pump is stopped. Control unit. The pump device has a means for detecting a small amount of water,
The control unit determines that the pump is in the light load state when detecting the small amount of water,
The control unit according to claim 12 or 13. The pump device includes a pressure gauge that measures a discharge pressure of the pump, and controls the pump at a variable speed based on a pressure deviation that is a difference between a predetermined target pressure and the discharge pressure,
When the cause of the trip is an input undervoltage of the variable speed controller and the operating state during trip is such that the pressure deviation is within a predetermined first pressure deviation threshold value, the control unit causes the variable speed control to be performed. The control unit according to any one of claims 1 to 14, which permits a retry operation of the container. The pump device includes a pressure gauge that measures a discharge pressure of the pump, and controls the pump at a variable speed based on a pressure deviation that is a difference between a predetermined target pressure and the discharge pressure,
When the cause of the trip is an input undervoltage of the variable speed controller and the operating state at the time of trip is a state in which the pressure deviation is equal to or more than a predetermined second pressure deviation threshold value, the control unit causes the variable speed control to be performed. The control unit according to any one of claims 1 to 15, which permits a retry operation of the container. The cause of the trip is an input undervoltage of the variable speed controller, and
17. The trip operation state permits the retry operation of the variable speed controller when the rotation speed of the pump is equal to or lower than a predetermined light load rotation threshold value, according to any one of claims 1 to 16. Controller unit.   When the cause of the trip is an input undervoltage of the variable speed controller, the control unit permits the retry operation of the variable speed controller when the input undervoltage is resolved within a predetermined time. 17. The control unit according to any one of 17. The control unit is a control unit that communicates with the variable speed controller,
The control unit, when receiving information including the protection stop from the variable speed controller, transmits an instruction for acquiring the cause of the trip to the variable speed controller,
The control unit according to any one of claims 1 to 18. The control unit sets a retry operation upper limit number of times of the variable speed controller based on the cause of the trip when the variable speed controller stops protection.
The control unit prohibits operation of the variable speed controller when the number of retry operations of the variable speed controller reaches the upper limit number of retry operations.
A control unit according to any one of claims 1 to 19. The control unit, when the variable speed controller is protection stopped, changes the control parameter of the variable speed controller based on the cause of the trip, and executes the retry operation,
The control unit according to any one of claims 1 to 20. A control unit according to any one of claims 1 to 21,
A pump driven by an electric motor by the at least one variable speed controller;
Equipped with
The electric motor-driven pump connected to the variable speed controller in which the retry operation is permitted continues predetermined automatic water supply,
The electric motor driven pump connected to the variable speed controller in which the retry operation is prohibited is stopped for protection.
Pump device. A control unit according to any one of claims 1 to 21,
A pump driven by an electric motor by the at least one variable speed controller;
Equipped with
The control unit sets a first upper limit number as a retry operation upper limit number of the variable speed controller for the electric motor driven pump connected to the variable speed controller permitted to perform the retry operation; For the motor-driven pump connected to the variable speed controller in which the retry operation is prohibited, a second upper limit number less than the first upper limit number is set as the retry operation upper limit number of the variable speed controller. ,
The control unit prohibits operation of the variable speed controller when the number of retry operations of the variable speed controller reaches the upper limit number of retry operations.
Pump device.

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