JP6268299B2 - Water supply equipment - Google Patents

Description

  The present invention relates to a water supply apparatus using a plurality of pumps that are driven by a plurality of inverters that are respectively speed-controlled by electric motors.

  It is desirable that the water supply apparatus using a plurality of pumps driven by a plurality of inverters that are respectively speed controlled by a plurality of inverters change the control method according to the time of day or the day of the week. In general, a method is known in which a clock (timer unit) is provided and control is performed in accordance with time. (See Patent Document 1)

JP2012-229699A

  However, in the control method using the above-described prior art, a timepiece (timer unit) must be used, and the timepiece must always be energized or provided with a battery or a battery. Even when the battery is provided, the time information may be lost if a power failure occurs when the battery reaches the end of its life.

  An object of this invention is to perform time management of a water supply apparatus, without using a timer unit.

  In order to solve the above problems, for example, the configuration described in the claims is adopted. The present invention includes a plurality of means for solving the above-described problems. For example, the temperature of the motor housing is detected by a temperature detector provided in the inverter, and the detected temperature and the operating state of the motor are used. The time is estimated based on the calculated temperature change.

  According to the present invention, control according to time can be performed without using a timer unit, and stable water supply can be performed.

It is the figure which showed the external view with which the electric motor for pump drive and the inverter were united. It is an expanded view of the electric motor and inverter of FIG. It is a figure which shows the whole structure of the water supply apparatus of the present Examples 1-3. It is a circuit block diagram of the power converter device of the present Examples 1-3. It is a figure which shows the content of the volatile memory among the data contents of the memory | storage part of the inverter of the present Examples 1-3. It is a figure which shows the content of the non-volatile memory among the data contents of the memory | storage part of the inverter of the present Examples 1-3. It is a figure which shows the main control processing flow of the present Examples 1-3. It is a figure which shows the temperature measurement process flow of the present Examples 1-3. It is a figure which shows the driving | running state measurement process flow of the present Examples 1-3. It is a figure which shows the temperature determination processing flow of the present Examples 1-3. It is a figure which shows the time setting process flow of the present Examples 1-3. It is a figure which shows the minimum instruction | command speed setting processing flow of the present Examples 1-3. It is a figure which shows the content of the non-volatile memory among the data contents of the memory | storage part of the control apparatus of the present Example 3.

Embodiments of the present invention will be described below with reference to the drawings.
Example 1 is a water supply apparatus using a pump driven by an electric motor whose speed is controlled by an inverter. The inverter is attached to a part of a housing that forms the outer periphery of the armature of the electric motor, and the inverter The temperature of the housing is detected using a temperature detector provided in the housing. Then, the temperature of the housing is detected using the temperature detector, the operating state of the motor is judged from the load current value of the motor and the rotational speed of the motor, and the time is estimated from the detected temperature and the operating state of the motor. It is. In addition, by setting the minimum value of the motor speed at a predetermined time stored in advance, the load value is suddenly changed (a sudden increase in the amount of water used), or the minimum value of the motor speed is set low. Energy-saving operation is performed during times when water is not used. That is, the time is estimated from the housing temperature, and suitable control according to the time is performed.

  First, the relationship between the electric motor and the inverter, which is a premise of the present embodiment, will be described with reference to the drawings. FIG. 1 is a diagram showing an external view in which an electric motor for driving a pump and an inverter are integrated. In FIG. 1, reference numeral 1 denotes a cover that covers the outer periphery of the synchronous motor main body, 2 denotes a cooling cover 2 that will be described later, and cooling covers 2 and 3 that incorporate a cooling fan 25 are attached to the outer peripheral surface of the cover 1. 4 is a terminal box with a built-in noise filter, 5 is an end bracket, and 6 is a rotating shaft formed integrally with the rotor of the electric motor.

  FIG. 2 is a development view of each part of the motor and the inverter housed in the cover 1 described above. In FIG. 2, 9 is an electric motor housing, and cooling fins 22 are formed on a part of the outer peripheral surface thereof. Also. Although not shown in the drawing, a stator and a rotor of an electric motor are inserted inside the housing 9, and 24 is an end attached to the end of the housing 9 on the side opposite to the end bracket 5 described above. A bracket 25 is a cooling fan attached to the rotary shaft 6 outside the end bracket 24. Further, the inverter 7 is attached to the flat surface 23 of the housing 9 through an opening 21 provided in a part of the cover 1, and then the cover 3 for protecting the inverter 7 is attached from the outside.

  Moreover, since the inverter has a power switching element or the like as a heat generating element, a temperature detector is provided for the purpose of monitoring and protecting the heat generation state. Reference numeral 26 denotes a control board case, and 27 denotes a smoothing capacitor case. And the cooling cover 2 mentioned above is attached to the other edge part (left end of a figure) of the housing 9. FIG. Moreover, the code | symbol 8 in a figure has shown the small hole for taking in external air formed in mesh shape in the approximate center part of the wall surface of the said cooling cover 2. FIG.

  In other words, the inverter 7 is directly attached to a part of the flat surface 23 of the housing 9 of the electric motor. The inverter 7 is thermally integrated with a housing made of a material having excellent heat conductivity, and is installed inside the inverter. The temperature of the inverter and the housing can be managed integrally with a certain temperature detector.

  Next, the whole structure of the water supply apparatus of a present Example is demonstrated. In FIG. 3, reference numerals 10-1, 10-2, and 10-3 denote pumps. It is driven by an electric motor indicated by 20-1, 20-2, 20-3. Here, for the sake of convenience, the number 1 pump, the number 2 pump, the number 3 pump, and the number 1 motor, the number 2 motor, and the number 3 motor are referred to from the smaller number. The suction side of these pumps is connected to the water source side via a suction pipe denoted by 11. The water source side receives water from a water main (not shown) in the direct connection system, and receives water from a water receiving tank (not shown) in the water receiving tank system. 12-1, 12-2, 12-3, 14-1, 14-2, 14-3 are gate valves, 13-1, 13-2, 13-3 are check valves, and 15 is a water supply pipe. Reference numeral 17 denotes a pressure detection means that is provided in the water supply pipe 15 and generates an electrical signal in accordance with the pressure. Based on the detection value of the pressure detection means, the pump discharge pressure is controlled (for example, discharge pressure constant control, estimated terminal pressure constant control). Further, as the demand side, when the end of the water supply pipe 15 is a direct-feed type, it is connected to the demand side water supply pipe and supplied to a faucet of an apartment house, for example. In the case of a high water tank type, it is connected to this demand side water supply pipe to supply water to the high water tank. Reference numeral 18 denotes a pressure tank provided in the water supply pipe 15 for suppressing rapid pressure fluctuations.

  The No. 1 inverter, No. 2 inverter, No. 3 inverter indicated by 30-1, 30-2, and 30-3 are supplied with power from the power source side, and are indicated by 32-1, 32-2, and 32-3, respectively. By changing the frequency of the output current by the power converter, the rotational speeds of the electric motors 20-1, 20-2, 20-3 are changed and driven. Reference numerals 31-1, 31-2, and 31-3 denote arithmetic processing units, and 34-1, 34-2, and 34 according to the control parameters stored in the storage units indicated by 33-1, 33-2, and 33-3. The motors 20-1, 20-2, and 20-3 are operated / stopped and the rotational speed is changed according to the signal input from the signal processing unit indicated by -3.

  Reference numeral 40 denotes a control device that manages the number of operating pumps through the inverters 30-1, 30-2, and 30-3. Reference numeral 41 denotes an arithmetic processing unit which controls the number of operating pumps according to a signal input from the signal processing unit 44 according to a control parameter stored in the storage unit 43. The control device 40 and the inverters 30-1, 30-2, 30-3 are connected by communication / control lines indicated by 50-1, 50-2, 50-3, respectively, and the control device 40 and the inverters 30-1, 30- 2, exchanges signals necessary for the control of 30-3.

  FIG. 4 shows a circuit configuration diagram of the power converters 32-1, 32-2, and 32-3 (represented by reference numeral 32 in FIG. 4) in the present invention. The input AC power is converted into DC power by the forward converter 61. The converted direct current power is smoothed by the smoothing capacitor 62 and then converted into alternating current power of an arbitrary frequency by the inverse converter 63 constituted by a power switching element, so that the rotating electrical machine 20 (20-1, FIG. 3). 20-2, 20-3). The inverse converter is driven by a drive circuit 67. The temperature information detected by the temperature detector 66 is input to the control circuit 64, and the drive circuit 67 is controlled by a command from the control circuit 64 to increase or decrease the speed. Various settings can be made by the operation display unit 65 connected to the control circuit 64.

  The smoothing capacitor 62 is housed in the capacitor case 27, the control circuit 64 is housed in the control board case 26, and is structurally disposed at a position away from the power conversion case 3.

  FIG. 5 shows the contents of the volatile memory and the nonvolatile memory stored in the storage unit in the control board of the inverter. In addition, it does not have a memory | storage part in a control board, and it does not interfere even if it attaches a memory | storage device outside and substitutes.

  FIG. 5A shows the contents stored in the volatile memory in the storage unit. The current pump discharge side pressure DpN is stored at address 1001 of the volatile memory. Address 1002 stores the speed (output operating frequency) HzN currently commanded by the inverter to the motor, and address 1003 stores the current output current value (load current value of the motor) AmN of the inverter. . It is possible to estimate the inverter load status and hence the amount of water output from the pump from HzN and AmN. From the DpN and the amount of water estimated from HzN and AmN, the operating point of the pump (discharge side pressure, amount of water used) can be determined. can do. A value detected by the temperature detection means is stored at address 1004 as the current temperature detection value TeN. Address 1005 stores the current minimum command speed (minimum frequency) HLN set in the minimum command speed setting process described later.

  The remaining time TN1 of the temperature measurement cycle management timer is stored at address 1006. The remaining time TN2 of the operation state measurement cycle management timer is stored at address 1007. Address 1008 stores the current time (elapsed time from midnight) TiN, which is set in a time setting process described later. An elapsed time TeS from the start of temperature measurement is stored at address 1009.

  The temperatures of the electric motor and the inverter are not loads at the moment when the temperatures are detected, but change due to integration of the load state up to that point. For this reason, the integrated value HzS of the command speed measured at the operating state measurement cycle is stored at address 1101, and the value (average value) HzA obtained by dividing the integrated value HzS by the averaging number AvC described later is stored at address 1102. . Similarly, with respect to the current value, the integrated value AmS of the output current value measured at the operating state measurement cycle is stored at address 1201, and the integrated value AmS is divided by the averaging count AvC (average value) at address 1202. Store AmA.

  In the address 1301, a determination flag TeF for executing a temperature determination process described later when the temperature measurement period is reached is stored. When TeF is 0, the temperature determination process is not executed, and when TeF is 1, the temperature determination process is performed.

  FIG. 5B shows the contents stored in the nonvolatile memory in the storage unit. The target discharge side pressure DpL at zero water volume is stored at address 2001 in the non-volatile memory, and the target discharge side pressure DpH at the specified water volume is stored at address 2002. When estimating the pressure at the demand side end to be constant and performing water supply control (in the case of estimated terminal pressure constant control), DpL is the value obtained by subtracting the pipe resistance from the customer specification pressure, so that DpL <DpH . When water supply control is performed so as to make the discharge side pressure of the water supply device constant without being aware of the demand side end (in the case of constant discharge pressure control), DpL = DpH.

  A command speed (minimum speed) at a water amount of zero is stored in addresses 2011 to 2013. In order to grasp the time and suppress the pressure drop by setting the command speed to a higher value in the morning and evening when the demand is large and the water amount fluctuation is severe in order to obtain an energy-saving effect at night. In the address, the command speed HzL at night water amount zero is stored, in the address 2012, the command speed HzD at normal water amount zero is stored, and in the address 2013, the command speed HzM at morning and evening water amount zero is stored. The command speed (maximum frequency) HzH at the specified water volume is stored at address 2014.

Address 2021 stores the motor cooling capacity (cooling fan cooling capacity) CoK. The number of rotations of the cooling fan also changes according to the number of rotations of the motor (inverter command speed). The constant k1 is used in a certain number of rotations range, and the cooling amount is set to HzA × CoK × k1.・ ・ ・ ・ ・ ・ Equation 1
Can be approximated as: Alternatively, it may be approximated by a higher-order equation over the entire rotation speed range.

The address 2022 stores a temperature increase coefficient (temperature increase amount with respect to load current) WaK of the electric motor. The temperature rise of the motor and inverter varies depending on the output current value (load current value), and the constant k2 is used to set the temperature rise amount to AmA x WaK x k2 ... Formula 2
Can be approximated as: It can be approximated by a higher order expression more accurately.

  The set time (cycle for measuring temperature) TM1 of the temperature measurement cycle management timer is stored at address 2031. Stored at address 2032 is a set time (cycle for measuring the driving state) TM2 of the driving state measuring cycle management timer. Address 2033 stores a set time TeT from the start of temperature measurement until the time is determined.

  At address 2101, the command speed and the number of times AvC for averaging the output current value are stored. When the temperature measurement interval TM1 is sufficiently long, the averaging number AvC is preferably set equal to the number of times of measuring the command speed and the output current value while measuring the temperature once. When the temperature measurement interval TM1 is short, the averaging number AvC is preferably set to be equal to or more than the number of times of measuring the command speed and the output current value while measuring the temperature once. From the viewpoint of facilitating control, the averaging count AvC is set to be equal to the number of times the command speed and output current value are measured while measuring the temperature once, and when the measurement count reaches the averaging count AvC. It is desirable to store the temperature detection value TeN, the command speed and the average value of the output current HzA, AmA, and reset the integrated value HzS, AmS of the command speed and the output current value.

  At the address 3011, the determination temperature (ambient temperature) T01T determined by the temperature determination process described later at the first temperature detection (time 1), the command speed T01H at the time 1 at the address 3012, and the time 1 at the address 3013 The output current value T01A at is stored. In this embodiment, the temperature measurement cycle TM1 is set to 60 (60 minutes = 1 hour), and the temperature is detected 72 times (4320 minutes = 72 hours = 3 days). Store the current value. Especially in outdoor installations, the change in temperature due to the weather (sunshine) is large, so the measurement is performed 72 times so that the time is accurately determined regardless of the weather. Therefore, it is desirable that the measurement time (cycle × number) is large, but it is preferably about 3 days in consideration of the time until the first time setting. Even after the first time determination, the determination temperature, command speed, and output current value at each time are periodically stored, the time determination is performed, and the average value with the previous determination time is set as a new determination time. Accurate time can be grasped. However, if the purpose is to perform the determination up to the day of the week, a measurement of 10080 minutes (= 168 hours = 7 days) is required.

  Address 4001 stores the start time PT1S of the first time zone (for example, morning) when the load increases, and address 4002 stores the end time PT1E of the first time zone when the load increases. The start time PT2S of the second time zone (for example, evening) when the load increases is stored at address 4003, and the end time PT2E of the second time zone when the load increases is stored at address 4004. Conversely, the start time ST1S of the first time zone (eg, nighttime) when the load decreases is stored at address 4101, and the end time ST1E of the first time zone when the load decreases is stored at address 4102. The start time ST2S of the second time zone in which the load decreases (for example, after noon) is stored at address 4103, and the end time ST2E of the second time zone in which the load decreases is stored at address 4104. When setting the time zone precisely according to the increase or decrease of the load, it is desirable to set the temperature measurement cycle to half or less of the time width to be set, but the ambient temperature does not change rapidly and the demand for water supply However, the temperature measurement period is about 30 to 60 minutes.

  Address 5001 stores a flag TJu indicating that the time determination is completed. The minimum command speed setting process described later is executed after confirming that TJu is 1 (time determination has been completed).

  FIG. 6 is a main control processing flowchart of this embodiment. First, initialization processing of various functions is performed in 100 steps, and each control from 200 steps to 800 steps is repeatedly executed. In step 200, communication control processing between the control device and the inverter is performed. In the communication control process, signals are exchanged using communication / control lines indicated by 50-1, 50-2, and 50-3 in FIG.

  In step 300, a temperature measurement process is performed. When the temperature measurement period is reached, a process for performing a temperature determination process is performed. In step 400, an operation state measurement process is performed. When the operation state measurement cycle is reached, a process for storing the command speed and the output current value is performed. In step 500, a temperature determination process is performed, and a determination temperature (ambient temperature) is calculated and stored from the temperature detection value, the command speed, and the output current value.

  In step 600, a time setting process is performed, and the time is estimated and set based on the relationship between a plurality of temperature determination results (a plurality of determination temperatures). In step 700, the set time is compared with the time of increase or decrease of the load stored in advance, and processing for changing the minimum command speed is performed in a time zone where the load fluctuates from the normal time.

  In step 800, pump control processing is performed. In residential water supply etc., the estimated terminal pressure constant control and discharge pressure constant control are mainly performed. In either control method, the pump discharge side pressure is controlled to the customer desired pressure by the change of the rotation speed by the inverter. . In a water supply apparatus having a plurality of pumps, when the demand water amount cannot be supplied by one pump, the second pump starts operation, and the demand is satisfied by parallel operation.

  FIG. 7 is a process flow diagram of the temperature measurement process. In step 310, it is determined whether the remaining time TN1 of the temperature measurement cycle management timer is 0. If TN1 is 0, the process proceeds to step 311. The temperature detected by the temperature detector in step 311 is stored in the current temperature detection value TeN, and the execution flag TeF of the temperature determination process is set to 1 (execution) in step 312. In step 313, the temperature measurement cycle management timer set value TM1 is set in the remaining time TN1 of the temperature measurement cycle management timer, and the process returns to the main control flow. The reason why TM1 is set to TN1 in step 313 is to perform temperature measurement again after the period TM1.

  If the remaining time TN1 of the temperature measurement cycle management timer is not 0 in step 310, the remaining time TN1 of the temperature measurement cycle management timer is counted down and stored in step 314. Thereafter, the process returns to the main control flow.

  FIG. 8 is a process flow diagram of the operation state measurement process. In step 410, it is determined whether the remaining time TN2 of the operation state measurement cycle management timer is 0. If TN2 is 0, the process proceeds to step 411. In step 411, the speed (command speed, output frequency) HzN currently instructed by the inverter to the electric motor is stored, and in step 412 HzN is added to the integrated value HzS of the command speed to update HzS. In step 413, the current value (load current value) AmN that the inverter is currently outputting to the electric motor is stored. In step 414, AmN is added to the integrated value AmS of the output current value, and AmS is updated. In step 415, the operation state measurement cycle timer set value TM2 is set in the remaining time TN2 of the operation state measurement cycle management timer, and the process returns to the main control flow. The reason why TM2 is set to TN2 in step 415 is to perform the operation state measurement process again after the period TM2.

  If the remaining time TN2 of the operation state cycle management timer is not 0 in step 410, the remaining time TN2 of the operation state measurement cycle management timer is counted down and stored in step 416. Thereafter, the process returns to the main control flow.

FIG. 9 is a process flow diagram of the temperature determination process. In step 510, it is determined whether the execution flag TeF of the temperature determination process is 1 (execution). If TeF is 1 (execution), the process proceeds to step 511. If TeF is 0 (none), the process proceeds to the main control flow. Return. In step 511, the command speed average value HzA is calculated from the command speed integrated value HzS and the averaging count AvC.
HzA = HzS ÷ AvC ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Equation 3
In step 512, the cooling amount is calculated from the average value HzA of the command speed and the cooling coefficient CoK (Equation 1). In step 513, the average value AmA of the output current values is calculated from the integrated value AmS of the output current values and the averaging count AvC.
AmA = AmS ÷ AvC ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Equation 4
In step 514, the temperature rise amount is calculated from the average value AmA of the output current and the temperature rise coefficient WaK (Formula 2). In step 515, the integrated value HzS of the command speed is returned to 0, and in step 516, the integrated value AmS of the output current value is returned to 0. In step 517, a determination temperature is calculated from the current temperature detection value TeN, the cooling amount and the temperature increase amount obtained from equations 3 and 4, and if it is the first determination, it is stored in the determination temperature T01T at time 1, and the determination n If it is the second time, it is stored in the determination temperature TnT at time n.
(Determination temperature) = TeN− (temperature increase amount) + (cooling amount) Equation 5
In step 518, the temperature determination process execution flag TeF is set to 0 (none), and the process returns to the main control flow.

FIG. 10 is a process flow diagram of the time setting process. In step 610, it is determined whether the temperature measurement elapsed time TeS has reached the temperature measurement time TeT. If it has reached, the process proceeds to step 611, and if not, the process returns to the main control flow. In step 611, data having the highest value among the determination temperatures is set as a time “3 pm (900 minutes have elapsed since midnight)”. 0:00 pm is calculated from the difference between the time set at “3 pm” in step 612 and the current temperature measurement elapsed time TeS. For example, if data “3 pm (900 minutes elapsed)” is detected in the 30th measurement (1800 minutes elapsed) at a measurement period of 60 minutes, “0:00 am” is 900 minutes before “3 pm”. Because
1800−900 = 900 Equation 6
From the time when 900 minutes have elapsed since the start of temperature measurement, or the next day “0:00 am” is 540 minutes after “3 pm”
1800 + 540 = 2340 ... Equation 7
From this, it can be seen that 2340 minutes have elapsed since the start of temperature measurement. This is assumed to be “midnight” (reference time).

In step 613, the current time TiN can be calculated from “midnight” and the measurement elapsed time TeS from the start of measurement to the present (60 minutes × 72 times = 4320 minutes for 72 measurements).
4320-2340 = 1980 Equation 8
Since one day is 1440 minutes (24 hours), if the solution of Equation 8 is 1440 or more, 1440 is subtracted.
1980-1440 = 540 Equation 9
Therefore, it can be calculated as 9:00 am from 540 minutes (9 hours).

  In step 614, the time determination completion flag TJu is set to 1 (completed). In step 615, the temperature measurement elapsed time TeS is returned to 0, and the process returns to the main control flow.

  Although the extraction method of “3 pm” in step 612 is the highest determination temperature, the average value of the three data every 1440 minutes (= 24 hours) may be the highest, or the lowest determination temperature It may be “6:00 AM”. Or you may determine by the change point of temperature (decrease from rise, rise from decrease).

  FIG. 11 is a process flow diagram of the minimum command speed setting process. In step 710, it is determined whether the time determination completion flag TJu is 1 (completed). If TJu is 1 (completed), the process proceeds to step 720. If TJu is 0 (incomplete), the process proceeds to step 763.

  In step 720, it is determined whether or not the current time TiN is a time zone between PT1S and PT1E set as a time zone in which the load increases. If TiN is between PT1S and PT1E, the processing proceeds to step 761. If the time zone is not between PT1S and PT1E, the process proceeds to step 730. Similarly, in step 730, it is determined whether the current time TiN is a time zone between PT2S and PT2E set as a time zone in which the load increases. If TiN is between PT2S and PT2E, If it is determined that the time period is not between PT2S and PT2E, the process proceeds to step 740.

  In step 740, it is determined whether the current time TiN is a time zone between ST1S and ST1E set as a time zone in which the load decreases. If TiN is between ST1S and ST1E, the flow proceeds to step 762. If the time zone is not between ST1S and ST1E, the process proceeds to step 750. Similarly, in step 750, it is determined whether the current time TiN is a time zone between ST2S and ST2E set as a time zone in which the load decreases. If TiN is between ST2S and ST2E, If it is not the time zone between ST2S and ST2E, it will progress to 763 step.

  In the case of proceeding to step 761, the current minimum command speed HLN is set to the command speed (the lowest frequency in the morning and evening) HzM in the morning and evening water quantity zero, and the process returns to the main control flow. When the routine proceeds to step 762, the command speed (minimum frequency at night) HzL is set to the current minimum command speed HLN, and the flow returns to the main control flow. When the routine proceeds to step 763, the current minimum command speed HLN is set to a normal command speed (normal minimum frequency) HzD at zero water volume, and the process returns to the main control flow.

Another embodiment of the present invention will be described.
In the second embodiment, the time is obtained by the same method as in the first embodiment, but the time zone during which the load increases / decreases is not input in advance from addresses 4001 to 4104, but addresses 3011 to 3723. The load increase / decrease is determined on the basis of the output current value stored at each time, and the time zone during which the load increases / decreases is automatically stored from address 4001 to address 4104.

  According to the method of the present invention, it is not necessary to predict the load in advance and input the time zone during which the load increases / decreases, and furthermore, the time zone is automatically input based on the actual load data. It is possible to grasp and set changes in load. In addition, when setting the time periodically, the control always refers to the most recent load state by reviewing (resetting) the time zone during which the load increases / decreases each time the time is set. Is possible.

  The reference value for determining the increase / decrease in load based on the output current value at each time may be preset in the volatile memory, but the average value of the stored output current values at each time, Alternatively, it is desirable to obtain the reference value by calculation based on the median.

  Further, in the methods of the first and second embodiments, when the water supply apparatus having a plurality of pumps cannot supply the demand water amount with one pump, the second pump starts operation, and the demand is increased in parallel operation. In general, a confirmation time is provided before starting the parallel operation. The confirmation time until the start of the parallel operation is preferably set to a shorter confirmation time than usual so as to prevent the pressure from decreasing in the time when the load increases.

Still another embodiment of the present invention will be described.
In the third embodiment, the time is determined in the control device, and the set value of the time and the set value of the minimum command speed are transmitted to each inverter through the communication / control line.

  FIG. 12 shows the contents of the nonvolatile memory stored in the storage unit in the control board in the control device. In addition, it does not have a memory | storage part in a control board, and it does not interfere even if it attaches a memory | storage device outside and substitutes.

  The contents of the volatile memory from address 2001 to address 2101 and from address 4001 to address 5001 are the same as the contents stored in the inverter.

  At address 3014, the temperature (ambient temperature) T011 determined by the No. 1 inverter at the time of the first temperature detection (time 1), the temperature (ambient temperature) T012 determined by the No. 2 inverter at the time 1 at address 3105, At address 3106, the temperature (ambient temperature) T013 determined by the No. 3 inverter at time 1 is stored. In this embodiment, the temperature measurement cycle TM1 is set to 60 (60 minutes = 1 hour), and since the temperature is detected 72 times (4320 minutes = 72 hours = 3 days), the judgment temperature of each inverter at each time is stored up to address 3726. To do. The control board determines the time based on the average value of these determination temperatures, and sets the minimum command speed according to the time.

  By determining the time in the control device, it is possible to perform operation at a time standardized for all inverters and a minimum command speed corresponding to the time. Furthermore, the time can be determined more accurately by increasing the temperature data to be detected.

Claims (12)

A pump,
An electric motor for driving the pump;
A cooling means attached to each of the motors;
An inverter for controlling the rotational speed of the electric motor;
In the water supply apparatus having a temperature detector attached to a housing constituting the outer periphery of the armature of the motor,
The inverter uses the temperature detector to detect the housing temperature of the electric motor or the temperature of the inverter, calculates the ambient temperature from the detected temperature and the operating state of the electric motor, and is calculated A water supply apparatus that estimates time based on a change in temperature. In the water supply apparatus of Claim 1,
The operation state of the electric motor is determined from the load current value of the electric motor and the rotation speed of the electric motor. In the water supply apparatus of Claim 2,
The inverter obtains the temperature increase based on the load current value, based on said rotational speed determined amount of cooling, to a temperature detected by the temperature detector, pulling to the difference of the temperature increase, the cooling amount by adding feed water system you and calculates the ambient temperature. In the water supply apparatus of Claim 1,
The said inverter sets the minimum value of the rotation speed of an electric motor high at the predetermined time memorize | stored previously, The water supply apparatus characterized by the above-mentioned. In the water supply apparatus of Claim 1,
The said inverter sets the minimum value of the rotation speed of an electric motor low at the predetermined time memorize | stored previously, The water supply apparatus characterized by the above-mentioned. In the water supply apparatus of Claim 1,
A plurality of the pump, the electric motor, and the inverter are installed,
A control device for controlling the plurality of inverters;
The said control apparatus shortens the confirmation time at the time of changing the driving | running number of the said pump with respect to the amount of water at the predetermined time memorize | stored previously. In the water supply apparatus of Claim 1,
The said inverter memorize | stores the correlation of the estimated time and the driving | running state of the said motor, The water supply apparatus characterized by the above-mentioned. In the water supply apparatus of Claim 7,
The inverter sets the minimum value of the rotation speed of the electric motor high in a time zone in which the load of the electric motor can be high. In the water supply apparatus of Claim 7,
The water supply device is characterized in that the inverter sets the minimum value of the number of revolutions of the motor to be low during a time period in which the state of low load on the motor continues. In the water supply apparatus of Claim 7,
A plurality of the pump, the electric motor, and the inverter are installed, and includes a control device that controls the plurality of inverters,
The said control apparatus shortens the confirmation time at the time of changing the driving | running number of the said pump with respect to the amount of water in the time zone when the load of an electric motor may be in a high state, The water supply apparatus characterized by the above-mentioned. Multiple pumps,
A plurality of electric motors that respectively rotate and drive the plurality of pumps;
A plurality of cooling fans respectively attached to the plurality of electric motors;
A plurality of inverters each changing the rotational speed of the plurality of electric motors;
In a water supply apparatus having a control device for controlling the plurality of inverters,
The plurality of inverters are attached to a part of the housing constituting the outer periphery of each armature of the plurality of electric motors, and the temperature of the housing is detected by a temperature detector provided in the inverter. Configured,
The control device detects the housing temperature of the plurality of electric motors or the temperature of the plurality of inverters using the temperature detector, and estimates the time from the detected temperature and the operating state of the electric motor. Water supply device to do. The water supply apparatus according to claim 11,
The controller is responsive to the temperature detected by the temperature detector.
Differentially the temperature increasing amount based on the load current value before Symbol conductive motive pull, based on the time estimated by the change of the computed ambient temperature by adding cooling amount based on the rotation speed of the electric motor of the plurality of inverters operation and the water supply device is shall control the stop.

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