Blower and ventilation device

Abstract

Provided is a blower wherein a control device acquires, as a ripple voltage initial value, a ripple voltage value of a DC voltage generated by an electrolytic capacitor, sets a lifespan assessment reference value on the basis of the ripple voltage initial value, acquires, as an assessment target value, the ripple voltage value of the DC voltage generated by the electrolytic capacitor, after setting the lifespan assessment reference value, and assesses the lifespan of the electrolytic capacitor on the basis of the lifespan assessment reference value and the assessment target value.

Description

Fans and ventilation equipment

[0001] The present disclosure relates to a blower and a ventilation device.

[0002] In a conventional power supply life assessment device, the life of an aluminum electrolytic capacitor is determined based on the value of the ripple voltage in the output of the aluminum electrolytic capacitor (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2007-244161

[0004] In the conventional power supply life assessment device described above, relationship data between load current and ripple voltage is prepared in advance. Then, a ripple voltage value corresponding to the current load is calculated from the current load current. However, in the case of a fan, the load varies depending on the condition of the piping connected to the fan, i.e., the length, diameter, shape, and routing of the piping. It is difficult to prepare relationship data between load current and ripple voltage for all fans before shipping from the factory, making it impossible to accurately determine the life of the electrolytic capacitor.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a blower and a ventilation device that can improve the accuracy of determining the lifespan of an electrolytic capacitor.

[0006] The blower according to the present disclosure has a blower body having a DC motor and an electrolytic capacitor that generates a DC voltage, and is equipped with a control device that supplies power to the DC motor and controls the DC motor, and the control device acquires a ripple voltage value in the DC voltage generated by the electrolytic capacitor as an initial ripple voltage value, sets a life determination reference value that serves as a standard for determining the life of the electrolytic capacitor based on the initial ripple voltage value, and after setting the life determination reference value, acquires the ripple voltage value in the DC voltage generated by the electrolytic capacitor as a determination target value, and determines the life of the electrolytic capacitor based on the life determination reference value and the determination target value.

[0007] According to the present disclosure, it is possible to improve the accuracy of determining the lifespan of an electrolytic capacitor.

[0008] 1 is a schematic configuration diagram showing the main parts of a ventilation device according to embodiment 1. It is a circuit diagram showing a partial block diagram of the control device of FIG. 1. It is a block diagram showing an example of a hardware configuration when the function of the control circuit of FIG. 2 is realized by software. It is a flowchart showing a reference value calculation process by the control circuit of FIG. 2. It is a flowchart showing a life determination process by the control circuit of FIG. It is a waveform diagram showing an example of a ripple voltage in embodiment 1.

[0009] Hereinafter, embodiments will be described with reference to the drawings. Embodiment 1. Fig. 1 is a schematic diagram showing the main components of a ventilation device according to embodiment 1. In the figure, ventilation device 10 includes a blower 11, an intake duct 12, and a blower duct 13. Blower 11 includes a housing 14, a blower main body 21, and a control device 31.

[0010] The housing 14 has a housing body 15, an inlet 16, and an outlet 17. The housing body 15 has a first side surface 15a and a second side surface 15b. The second side surface 15b faces the first side surface 15a. The inlet 16 is provided in the first side surface 15a. The outlet 17 is provided in the second side surface 15b.

[0011] The intake duct 12 is connected to the suction port 16. The blower duct 13 is connected to the discharge port 17.

[0012] The blower main body 21 is provided inside the housing main body 15. The blower main body 21 also has a scroll casing 22, a fan 23, and a DC (Direct Current) motor 24. The fan 23 is provided inside the scroll casing 22. A sirocco fan is used as the fan 23.

[0013] The DC motor 24 rotates the fan 23. As the fan 23 rotates, air outside the housing 14 is taken into the housing main body 15 through the air inlet 16, and air inside the housing main body 15 is discharged to the outside of the housing 14 through the air outlet 17. That is, an air path 18 is formed inside the housing 14 as shown by the arrow in FIG.

[0014] The DC motor 24 also has a rotation speed switching mechanism (not shown) that adjusts the rotation speed of the fan 23.

[0015] The control device 31 is electrically connected to the DC motor 24 via the DC motor line 25. The control device 31 supplies power to the DC motor 24 to drive the DC motor 24. The control device 31 also transmits and receives control signals to and from the DC motor 24 to control the DC motor 24.

[0016] A remote controller (not shown) is connected to the control device 31 via a communication line (not shown). The control device 31 supplies power to the remote controller. The control device 31 also transmits and receives various signals to and from the remote controller.

[0017] Fig. 2 is a circuit diagram showing, in partial blocks, the control device 31 shown in Fig. 1. The control device 31 includes an AC (Alternating Current) input circuit 32, a rectifier circuit 33, an electrolytic capacitor 34, a power supply circuit 35, a control circuit 36, and a voltage acquisition circuit 37.

[0018] The AC input circuit 32 is connected to an AC power supply 40. The AC power supply 40 is a commercial power supply. The AC input circuit 32 reduces noise applied from the AC power supply 40, and also reduces noise emitted outside the control device 31.

[0019] The AC input circuit 32 includes a plurality of capacitors 32 a and a coil 32 b. Each capacitor 32 a is, for example, a polypropylene capacitor or a ceramic capacitor. A ground terminal of the AC input circuit 32 is connected to the housing 14.

[0020] The voltage output from the AC input circuit 32 is applied to the rectifier circuit 33. The rectifier circuit 33 rectifies and converts the negative voltage into a positive voltage, i.e., performs full-wave rectification. The rectifier circuit 33 uses a diode bridge element.

[0021] The electrolytic capacitor 34 converts the voltage that has been full-wave rectified by the rectifier circuit 33 into a DC voltage Vm by smoothing the voltage. That is, the electrolytic capacitor 34 generates the DC voltage Vm.

[0022] The larger the load current, the greater the charge / discharge amount of the electrolytic capacitor 34. When the load current increases, the waveform of the DC voltage Vm becomes pulsating as shown in Figure 6. This voltage fluctuation is called a ripple voltage.

[0023] In the blower 11, as the rotation speed of the DC motor 24 increases, the amount of air discharged increases, and the ripple voltage increases.

[0024] The DC voltage Vm generated by the electrolytic capacitor 34 is applied to the power supply circuit 35. The power supply circuit 35 converts the applied DC voltage Vm into a DC voltage that can drive the control circuit 36, for example, DC 12 V or DC 5 V, and applies the converted voltage to the control circuit 36.

[0025] The DC motor line 25 includes a pair of power lines 25 a and a control line 25 b. A DC voltage Vm is applied to the DC motor 24 via the pair of power lines 25 a.

[0026] The control circuit 36 ​​applies a control voltage to the DC motor 24 via the control line 25b. The control circuit 36 ​​also transmits and receives, to and from the DC motor 24, communications for driving the DC motor 24, communications for inputting the rotation state of the DC motor 24, and the like.

[0027] The voltage acquiring circuit 37 acquires the DC voltage Vm. The DC voltage Vm acquired by the voltage acquiring circuit 37 is input to the control circuit 36. The circuit configuration of the voltage acquiring circuit 37 is, for example, a circuit configuration in which the DC voltage Vm is divided by resistors and input to the control circuit 36 ​​as an analog voltage. However, the circuit configuration of the voltage acquiring circuit 37 is not limited to this circuit configuration.

[0028] The control circuit 36 ​​acquires, as the ripple voltage initial value Vrn, the ripple voltage value of the DC voltage Vm acquired from the voltage acquisition circuit 37 during the initial operation of the blower 11. The initial operation includes the first operation and multiple operations from the first operation onwards.

[0029] Furthermore, the control circuit 36 ​​sets a life determination reference value Vrs, which is the standard for determining the life of the electrolytic capacitor 34, based on the ripple voltage initial value Vrn.

[0030] Specifically, the control circuit 36 ​​sets the average value of two or more ripple voltage initial values ​​Vrn as the life determination reference value Vrs.

[0031] The control circuit 36 ​​is also set with a number of set initial values ​​a. After acquiring the initial ripple voltage values ​​Vrn of the number of set initial values ​​a, the control circuit 36 ​​subtracts the maximum and minimum values ​​from the initial ripple voltage values ​​Vrn of the number of set initial values ​​a and sets the average value of the remaining initial ripple voltage values ​​Vrn as the life determination reference value Vrs.

[0032] After setting the life determination reference value Vrs, the control circuit 36 ​​acquires, as a determination target value Vra, a ripple voltage value in the DC voltage Vm generated by the electrolytic capacitor 34. The control circuit 36 ​​also determines the life of the electrolytic capacitor 34 based on the life determination reference value Vrs and the determination target value Vra.

[0033] A set air volume is also set in the control circuit 36. When the control circuit 36 ​​acquires the initial ripple voltage value Vrn and the determination target value Vra, the control circuit 36 ​​drives the DC motor 24 so that the air volume of the blower main body 21 becomes the set air volume. The set air volume in the first embodiment is the maximum air volume.

[0034] Furthermore, the control circuit 36 ​​acquires the ripple voltage initial value Vrn and the determination target value Vra when the blower main body 21 is transitioning from a stopped state to an operating state.

[0035] A life coefficient α is set in the control circuit 36. The control circuit 36 ​​determines the life of the electrolytic capacitor 34 by comparing the value obtained by multiplying the life coefficient α by the life determination reference value Vrs with the determination target value Vra.

[0036] Next, a description will be given of the hardware configuration of the control circuit 36 ​​in Fig. 2. Fig. 3 is a block diagram showing an example of a hardware configuration in which the functions of the control circuit 36 ​​in Fig. 2 are realized by software.

[0037] When the functions of the control circuit 36 ​​are realized by software, the hardware configuration of the control circuit 36 ​​can include a processor 311, a memory 312, and an interface 313. The processor 311 performs arithmetic processing based on a program stored in the memory 312. The interface 313 inputs and outputs signals.

[0038] The control circuit 36 ​​may also include a display 314. The display 314 displays to the user the processing results of the processor 311. The display 314 may also be provided outside the control circuit 36.

[0039] The processor 311 may be an arithmetic unit, a microprocessor, a microcomputer, a central processing unit (CPU), or a digital signal processor (DSP).

[0040] Examples of memory 312 include non-volatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), and EEPROM (registered trademark) (Electrically EPROM).

[0041] The memory 312 stores programs and judgment tables. The processor 311 exchanges necessary information via the interface 313 and executes the programs stored in the memory 312. The processor 311 also executes the processing flows shown in Figures 4 and 5 by referring to the judgment tables stored in the memory 312. The processing results and judgment results by the processor 311 can be stored in the memory 312. The processing results and judgment results by the processor 311 can also be displayed on the display 314.

[0042] Next, Fig. 4 is a flowchart showing the reference value calculation process performed by the control circuit 36 ​​of Fig. 2. The reference value calculation process is a process for calculating the life determination reference value Vrs.

[0043] When the reference value calculation process is started, the control circuit 36 ​​determines in step S401 whether the blower main body 21 has transitioned from a stopped state to an operating state, i.e., whether operation has started. If the blower main body 21 has not transitioned from a stopped state to an operating state, i.e., is stopped, the control circuit 36 ​​repeats the process of step S401 until the operation of the blower main body 21 is started.

[0044] When the fan body 21 is transitioning from stopped to operating, the control circuit 36 ​​drives the DC motor 24 in step S402 so that the air volume of the fan body 21 becomes the set air volume, i.e., the maximum air volume. This maximizes the current consumption of the DC motor 24, and increases the ripple voltage in the DC voltage Vm.

[0045] Next, in step S403, the control circuit 36 ​​determines whether the number n of ripple voltage initial values ​​that have already been calculated and stored is less than the number a of set initial values. The number a of set initial values ​​is, for example, 5.

[0046] If the number n of ripple voltage initial values ​​is less than the set number a of initial values, the control circuit 36 ​​acquires the DC voltage Vm at a set cycle for a set time, for example, one minute, at step S404. The set cycle is, for example, 10 μsec.

[0047] The ripple voltage changes with a half cycle of the frequency of the AC power supply 40. Therefore, the set cycle is set to a time shorter than the half cycle of the frequency of the AC power supply 40. When the AC power supply 40 is a commercial power supply, the set cycle is set to a time shorter than 10 ms in a 50 Hz region and to a time shorter than 8.33 ms in a 60 Hz region.

[0048] Thereafter, in step S405, the control circuit 36 ​​extracts and stores the maximum value Vmn(max) and the minimum value Vmn(min) from the values ​​of the DC voltage Vm acquired within the set time. For example, when the number n of stored initial ripple voltage values ​​is 0, these values ​​are stored as Vm0(max) and Vm0(min), respectively.

[0049] Next, in step S406, the control circuit 36 ​​calculates and stores the initial ripple voltage value Vrn. The initial ripple voltage value Vrn is calculated by Vrn = Vmn(max) - Vmn(min). For example, Vr0 = 285 [V] - 255 [V] = 30 [V].

[0050] Next, in step S407, the control circuit 36 ​​stores the number n of stored ripple voltage initial values ​​as n = n + 1. For example, if the number n of already stored ripple voltage initial values ​​is 0, the control circuit 36 ​​sets the number n of stored ripple voltage initial values ​​as n = 0 + 1 = 1.

[0051] Thereafter, in step S408, the control circuit 36 ​​sets the air volume of the blower main body 21 to the air volume for normal operation, and returns to the process of step S401. The air volume for normal operation is, for example, the air volume specified by the remote controller. If the maximum air volume is specified as the air volume for normal operation, the control circuit 36 ​​maintains the maximum air volume.

[0052] In the process of step S403, when the number n of stored initial ripple voltage values ​​reaches the set number a of initial values, the control circuit 36 ​​calculates and stores a life determination reference value Vrs in step S409. The life determination reference value Vrs in the first embodiment is the average value of a-2 initial ripple voltage values ​​obtained by excluding the maximum and minimum values ​​from the a initial ripple voltage values.

[0053] The reason for excluding the maximum and minimum values ​​is that, for example, when the blower 11 is operated for the first time, the blower 11 may be in an open state, i.e., the intake duct 12 and the blower duct 13 may not be connected.

[0054] For example, if Vr0 = 30 [V], Vr1 = 40 [V], Vr2 = 40 [V], Vr3 = 40 [V], and Vr4 = 42 [V], then the maximum value Vr4 and the minimum value Vr0 are excluded, and Vrs = (40 + 40 + 40) / 3 = 40 [V].

[0055] Thereafter, the control circuit 36 ​​proceeds to a lifespan determination process in step S410, which determines whether the electrolytic capacitor 34 is nearing the end of its lifespan using the lifespan determination reference value Vrs.

[0056] Fig. 5 is a flowchart showing the lifespan determination process by the control circuit 36 ​​of Fig. 2. When the lifespan determination process starts, the control circuit 36 ​​determines in step S501 whether the fan main body 21 has transitioned from stopped to operating. If the fan main body 21 has not transitioned from stopped to operating, the control circuit 36 ​​repeats the process of step S501 until the fan main body 21 starts operating.

[0057] When the blower main body 21 is transitioning from stopped to operating, the control circuit 36 ​​drives the DC motor 24 in step S502 so that the air volume of the blower main body 21 becomes the set air volume, i.e., the maximum air volume. This maximizes the current consumption of the DC motor 24, and increases the ripple voltage in the DC voltage Vm.

[0058] Next, in step S503, the control circuit 36 ​​acquires the DC voltage Vm at a set interval for a set time period. The set time period and the set interval are the same as those in step S404 in the reference value calculation process of FIG.

[0059] Thereafter, in step S504, the control circuit 36 ​​extracts and stores the maximum value Vma(max) and the minimum value Vma(min) from the values ​​of the DC voltage Vm acquired within the set time.

[0060] Next, in step S505, the control circuit 36 ​​calculates and stores a determination target value Vra. The determination target value Vra is a ripple voltage value that is the target of lifespan determination. The determination target value Vra is calculated as Vra = Vma(max) - Vma(min). For example, Vra = 282 [V] - 240 [V] = 42 [V].

[0061] Next, in step S506, the control circuit 36 ​​determines whether the calculated determination target value Vra is smaller than the value obtained by multiplying the life determination reference value Vrs by the life coefficient α.

[0062] If Vra < α × Vrs is true, the control circuit 36 ​​determines that there is still time before the electrolytic capacitor 34 reaches the end of its life, and in step S507, the air volume of the blower main body 21 is set to the air volume during normal operation, and the process returns to step S501.

[0063] On the other hand, if the determination value Vra is equal to or greater than α×Vrs, the control circuit 36 ​​sets the air volume of the blower main body 21 to the air volume during normal operation in step S508. The control circuit 36 ​​also determines in step S508 that the electrolytic capacitor 34 is nearing the end of its life and issues an abnormality notification. The abnormality notification is displayed, for example, on a remote controller.

[0064] The life coefficient α is a value that varies from product to product and varies depending on the concept of the product. Furthermore, the life coefficient α is set in advance based on evaluation, calculation, simulation, etc. For example, a capacitor manufacturer specifies that the life of the electrolytic capacitor 34 is the time until the capacitance of the electrolytic capacitor 34 decreases by 20%. In this case, the life coefficient α is set to, for example, 1.25.

[0065] 6 is a waveform diagram showing an example of a ripple voltage in the first embodiment. The waveform of the ripple voltage has a triangular wave shape as shown in FIG. 6. If the determination target value Vra is smaller than the value α×Vrs obtained by multiplying the life determination reference value Vrs by the life coefficient α, the determination result in step S506 in FIG. 5 is "YES." If the determination target value Vra is equal to or greater than α×Vrs, the determination result in step S506 in FIG. 5 is "NO."

[0066] In the blower 11 and ventilation device 10, the ripple voltage value of the DC voltage Vm generated by the electrolytic capacitor 34 is acquired as the initial ripple voltage value Vrn. A lifespan determination reference value Vrs is set based on the initial ripple voltage value Vrn. After the lifespan determination reference value Vrs is set, the ripple voltage value of the DC voltage generated by the electrolytic capacitor 34 is acquired as the determination target value Vra. The lifespan of the electrolytic capacitor 34 is then determined based on the lifespan determination reference value Vrs and the determination target value Vra.

[0067] Therefore, it is possible to set the life determination reference value Vrs according to the operating environment of each fan 11 and the variations in the electrolytic capacitor 34. Therefore, it is possible to improve the accuracy of the life determination of the electrolytic capacitor 34.

[0068] This allows the DC voltage to be applied to the DC motor 24 to be stably generated by one electrolytic capacitor 34, while also reducing the space required for the control device 31.

[0069] Furthermore, the control circuit 36 ​​sets the average value of two or more ripple voltage initial values ​​Vrn as the life determination reference value Vrs, which allows a more appropriate life determination reference value Vrs to be set, thereby further improving the accuracy of life determination of the electrolytic capacitor 34.

[0070] Furthermore, the control circuit 36 ​​subtracts the maximum and minimum values ​​from the initial ripple voltage values ​​Vrn of the set initial value number a and sets the average value of the remaining initial ripple voltage values ​​Vrn as the life determination reference value Vrs. This makes it possible to set the life determination reference value Vrs according to the actual operating environment, thereby further improving the accuracy of the life determination of the electrolytic capacitor 34.

[0071] Furthermore, when the control circuit 36 ​​acquires the ripple voltage initial value Vrn and the determination target value Vra, it drives the DC motor 24 so that the air volume of the blower main body 21 becomes the set air volume. Therefore, by setting the set air volume so that the ripple voltage becomes large, it is possible to more clearly detect changes in the capacitance of the electrolytic capacitor 34, and further improve the accuracy of the lifespan determination of the electrolytic capacitor 34.

[0072] Furthermore, the set air volume in the first embodiment is the maximum air volume of the blower body 21. This allows for more clear detection of changes in the capacitance of the electrolytic capacitor 34, thereby further improving the accuracy of determining the lifespan of the electrolytic capacitor 34.

[0073] Furthermore, the control circuit 36 ​​acquires the ripple voltage initial value Vrn and the determination target value Vra when the blower main body 21 transitions from stopped to operating. Therefore, under similar conditions, the air volume of the blower main body 21 can be set as a set air volume and the ripple voltage initial value Vrn and the determination target value Vra can be acquired. This further improves the accuracy of the lifespan determination of the electrolytic capacitor 34. Furthermore, the influence on the normal operation of the blower 11 can be minimized.

[0074] Furthermore, the control circuit 36 ​​compares the value obtained by multiplying the life determination reference value Vrs by the life coefficient α with the determination target value Vra to determine the life of the electrolytic capacitor 34. Therefore, a more appropriate life coefficient α can be set for each type of blower 11, thereby further improving the accuracy of the life determination of the electrolytic capacitor 34.

[0075] The number of set initial values ​​a is not limited to 5, but may be, for example, 6 or more.

[0076] Furthermore, the life determination reference value Vrs does not necessarily have to be the average value of two or more ripple voltage initial values ​​Vrn, and one ripple voltage initial value obtained at a timing that is considered optimal may be used as the life determination reference value Vrs as is.

[0077] The set initial value number a may be input for each fan 11 by an external operation.

[0078] Furthermore, the set air volume is not necessarily limited to the maximum air volume, but may be an air volume smaller than the maximum air volume.

[0079] Furthermore, the timing for acquiring the ripple voltage initial value Vrn is not necessarily limited to the first few operations after the first operation, but may be after a certain number of operations have been performed since the first operation.

[0080] Furthermore, the ventilation device 10 may be, for example, a device that supplies outdoor air into a room, a device that exhausts indoor air to the outside, or a device that sends indoor air to another room.

[0081] Furthermore, the blower 11 may be a blower used for a device other than the ventilation device 10 .

[0082] 10 Ventilation device, 11 Blower, 21 Blower body, 24 DC motor, 31 Control device

Claims

1. A blower comprising: a blower body having a DC motor; and a control device having an electrolytic capacitor that generates a DC voltage, supplying power to the DC motor and controlling the DC motor, wherein the control device: obtains a ripple voltage value in the DC voltage generated by the electrolytic capacitor as an initial ripple voltage value; sets a life judgment reference value that serves as a standard for determining the life of the electrolytic capacitor based on the initial ripple voltage value; after setting the life judgment reference value, obtains the ripple voltage value in the DC voltage generated by the electrolytic capacitor as a judgment target value; and performs a life judgment of the electrolytic capacitor based on the life judgment reference value and the judgment target value.

2. The blower according to claim 1, wherein the control device sets an average value of two or more of the initial ripple voltage values ​​as the life determination reference value.

3. The blower according to claim 2, wherein the control device, after acquiring the set number of initial ripple voltage values, subtracts the maximum and minimum values ​​from the set number of initial ripple voltage values ​​and sets the average value of the remaining initial ripple voltage values ​​as the life judgment reference value.

4. A blower as claimed in any one of claims 1 to 3, wherein the control device drives the DC motor so that the air volume of the blower body becomes a set air volume when acquiring the initial ripple voltage value and the judgment target value.

5. The blower according to claim 4, wherein the control device acquires the initial ripple voltage value and the judgment target value when the blower body is in transition from stopped to operating.

6. A blower as claimed in any one of claims 1 to 5, wherein the control device judges the life of the electrolytic capacitor by comparing a value obtained by multiplying the life judgment reference value by a life coefficient with the judgment target value.

7. A ventilation device comprising a blower according to any one of claims 1 to 6.

Images