JP2005257258A - Fin filter unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a large fan filter unit (FFU) at low cost. <P>SOLUTION: With respect to each motor (e.g., synchronous motor) 3A-3C of a number of FFUs set in, for example, a clean room, a rectifying circuit 21 and an operation control circuit 22 are arranged commonly, and inverters 23A-23C, motor control circuit 24A-24C and detection parts 25A-25C are independently arranged, whereby the number of circuits or wiring is reduced. Accordingly, even if the scale is enlarged, the cost is never increased. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fan filter unit (hereinafter also referred to as FFU) installed in a clean room of a semiconductor factory or a chemical factory.

In a clean room, it is necessary to keep the air in the room at a certain level of cleanliness. Therefore, monitoring and control of the fan filter unit is necessary and indispensable.
FIG. 10 shows an example of an FFU monitoring / control system. In this system, a supervisory control computer CP provided in a central monitoring room is connected to a control device PLC that performs distributed control via a communication line such as Ethernet EN1. Further, the control device PLC is connected to the FFU device group (areas 1, 2, 3...) In the clean room CR via the Ethernet (registered trademark) EN2 and the interfaces IF1 to IF3 FFU communication lines L1 to L3.
Each FFU includes a motor / fan MF and a controller CN for controlling the motor / fan MF.
Furthermore, electric power is supplied to each FFU from a power source via power panel PW, distribution boards PW1 to PW3, and power lines PL1 to PL3.

The monitoring control computer CP is configured to be able to issue a selection command for clean room batch, area, or single unit to the FFU via the control device PLC, and the operation / stop, motor / fan rotation speed (FFU Command can be issued. From the FFU side, status information (operation / stop, failure, rotation speed, operation current value, etc.) of each motor is returned to the monitoring control computer CP in real time via the control device PLC.
Further, as shown in the figure, the FFU is provided with a controller CN for each unit and is connected to the FFU communication lines L1 to L3, so that the total number of FFUs is several hundred to several thousand. In such a large clean room CR, the number of connection points between the FFU communication lines L1 to L3 and the controller CN is great, and the following problems arise.

1) The wiring cost to the communication lines L1 to L3 of the controller CN is enormous.
2) The communication capacity needs to be increased, resulting in an increase in cost.
3) The number of connection points increases and the reliability of the communication function decreases.
4) The communication command speed from the monitoring control side and the status information return speed from the FFU side are reduced.
In addition, since the FFU-compatible controller CN is connected to each of the power lines PL1 to PL3 via the distribution boards PW1 to PW3 for each area from the power panel PW, the following problem also occurs.
5) Power line wiring costs increase.
Therefore, for example, there is a technique as shown in FIG. In this configuration, a plurality of DC brushless motors A and B connected in parallel are driven by a common drive circuit (inverter).
Japanese Unexamined Patent Publication No. 2003-116293 (page 4-5, FIG. 1)

The drive circuit (inverter) can be shared by a plurality of motors, so the cost can be reduced. However, since a plurality of DC brushless motors are driven by a common drive circuit (inverter), a plurality of DC brushless motors If the states are different, problems such as complicated positioning of the rotor at start-up and poor start-up in a strong headwind are assumed.
Accordingly, an object of the present invention is to prevent the above-described problems from occurring and to provide a large-scale FFU at a low cost.

In order to solve such a problem, according to the first aspect of the present invention, a drive circuit for each motor and fan provided in each of a large number of installed fan filter units is provided corresponding to each motor and fan. A rectifier circuit that supplies power to the motor and an operation control circuit that performs operation stop / speed setting / abnormality processing of the motor / fan are provided in common for the plurality of drive circuits.
According to a second aspect of the present invention, the drive circuit, the rectifier circuit, and the operation control circuit provided in common are mounted on a predetermined fan filter unit among a large number of installed fan filter units, and other fan filter units are provided. Each of the motors and fans provided in is supplied with power from a corresponding drive circuit via a motor cable.
Furthermore, in the invention of claim 3, a plurality of motors / fans are provided in one fan filter unit, and a drive circuit for each motor / fan is provided corresponding to each motor / fan in the fan filter unit, The rectifier circuit that supplies power to the drive circuit and the operation control circuit that performs operation stop / speed setting / abnormality processing of the motor / fan are provided in common for the plurality of drive circuits in the fan filter unit. Features.

In the first to third aspects of the invention, the rectifier circuit and the operation control circuit can be integrated (invention of the fourth aspect). In the fourth aspect of the invention, the drive circuit is also added. Thus, an integrated configuration can be obtained (invention of claim 5). In the inventions of the first to fifth aspects, the drive circuit for each motor can be composed of an inverter part, a motor control circuit part, and a motor current / temperature detection part (invention of claim 6). .
In the first to sixth inventions, the motor can be a synchronous motor or a DC brushless motor (the seventh invention). In the first to seventh inventions, the control circuit includes a serial communication circuit. Can be operated from outside or monitored externally via a serial communication circuit (invention of claim 8). In the inventions of claims 1 to 8, the operation control circuit includes The speed of the motor / fan can be set individually (invention of claim 9).

According to the present invention, an FFU having the following effects can be provided.
1) It can be provided at low cost while being large-scale (many units are used). This effect becomes more prominent as the number of units used increases.
2) The reliability of the communication monitoring system is improved.
3) The communication speed in the communication monitoring system can be increased.
4) It is possible to control stably even when the wind pressure is applied due to the influence of other fans.
5) When a failure occurs, maintenance can be performed by stopping only the failed motor.
6) Small size and space saving are possible.

FIG. 1 is a block diagram showing a first embodiment of the present invention. As shown in the figure, when three motors are installed in one FFU, one set of the rectifier circuit unit 21 and the operation control circuit 22 is provided in common, and the inverter units 23A to 23C and motor control circuits 24A to 24C. Three sets of current, temperature and temperature detection units 25 </ b> A to 25 </ b> C are provided for each motor, and this is configured as one controller 2. The operation control circuit 22 includes a speed setting circuit 221, an operation stop circuit 222, and an abnormality processing circuit 223, and is connected to the FFU communication line L shown in FIG. In addition, 1 is an AC power source, 3A to 3C are synchronous motors, 4A to 4C are loads, and FFU fans are assumed as the loads.
With such a configuration, the AC voltage of the AC power supply 1 is rectified and smoothed by the rectifier circuit unit 21, and the DC voltage is supplied to the inverter units 23A to 23C. The operation control circuit 22 performs speed setting, operation stop, monitoring of an abnormal state, etc., and outputs an operation command according to the result. That is, the setting values Sa, Sb, and Sc of the rotation speed set by the speed setting circuit 221 are output to the motor control circuits 24A to 24C. The motor control circuits 24A to 24C control the inverter units 23A to 23C according to the set values, and drive the motors 3A to 3C. Further, the currents and temperatures of the motors 3A to 3C are detected by the detection units 25A to 25C and output to the abnormality processing circuit 223. When the abnormality processing circuit 223 determines that the temperature and current are abnormal, the abnormality processing circuit 223 issues an abnormality report to the monitoring control computer via the FFU communication line and outputs an abnormality signal to the operation stop circuit 222. When the operation stop circuit 222 receives the abnormal signal, it outputs an abnormal stop command to the speed setting circuit 221. Upon receiving the abnormal stop command, the speed setting circuit 221 outputs a command for stopping the motor to the motor control circuits 24A to 24C corresponding to the abnormal motor in order to stop the abnormal motor operation. Stop the motor. The abnormal motor may be stopped by a command from the monitoring control computer that has received the abnormality report.

With the configuration described above, the power source wiring for driving the three motors 3A to 3C is only one set of U, V, and W phase wirings from the AC power source 1 to the controller 2, so that the external The number of wirings is reduced, and it can be configured at low cost. This effect becomes more prominent as the number of controllers is increased. Moreover, since only one set of the rectifier circuit unit 21 and the operation control circuit 22 is required inside the controller, the controller can be manufactured in a small size and at low cost. Furthermore, since the currents and temperatures of the inverter units 23A to 23C are individually detected, even if an abnormality occurs in any one of the motors 3A to 3C due to defects or malfunctions, this is detected and applicable. Only the motor can be stopped, and the influence on the whole can be reduced even when maintenance is performed.
Further, since the inverter units 23A to 23C are provided for the motor, a sufficient acceleration torque can be exhibited even in a state where the motor is rotated in reverse by the reverse wind, that is, idling, and acceleration can be performed without any problem. In other words, when the inverter units 23A to 23C are provided for each motor as shown in FIG. 1, in order to reliably start the motor from the idling state, for example, as shown in JP-A-2002-272198, A speed polarity detector for detecting the speed polarity, a speed absolute value calculator for calculating the absolute speed value, a multiplier for estimating the idling speed of the rotor from the speed polarity and the absolute speed value, and the idling speed of the rotor A method using a position estimator for estimating the magnetic pole position from the above may be adopted.

Although FIG. 1 shows a case where there are three motors, the number of motors is not limited to three, and two, four, or more may be provided in consideration of various conditions. it can. Further, the outputs sa, sb, and sc of the speed setting circuit 221 of the operation control circuit 22 can be set to the same value or different values for operation. Furthermore, the controller 2 is installed by mounting the rectifier circuit unit 21, the operation control circuit 22, the inverter units 23A to 23C, the motor control circuits 24A to 24C, and the motor current / temperature detection units 25A to 25C on a common printed circuit board or the like. It can be formed on the body, the cost can be reduced, and handling can be facilitated.
FIG. 2 is a block diagram showing a second embodiment of the present invention, which is a modification of the configuration of FIG.
The configuration in FIG. 2 is an example assuming a DC brushless motor as a motor, and position detectors 5A to 5C are provided. By outputting the position signals from the position detectors 5A to 5C to the motor control circuits 24A to 24C, sufficient acceleration torque can be exhibited even when the vehicle is rotated in the reverse direction due to a low speed or a headwind so that it can be accelerated without any problem. It is a thing. 2 is the same as that shown in FIG. 1 except that the position detectors 5A to 5C are provided, and a description thereof will be omitted.

FIG. 3 is a block diagram showing a third embodiment of the present invention, which is a modification of the configuration of FIG.
The configuration of FIG. 3 is obtained by adding a noise filter 6 to FIG. 1 and reduces noise for a control device installed in the vicinity of the FFU. In that case, since only one set of noise filters 6 is required for three motors, the controller can be made small and inexpensive.
FIG. 4 is a block diagram showing a fourth embodiment of the present invention, which is a modification of the configuration of FIG.
The configuration of FIG. 4 uses a serial communication line SL as the FFU communication line of FIG. A serial communication circuit 7 connected to the serial communication line SL is provided in each FFU. RS485, CAN (Controller Area Network), etc. can be used as the serial communication line SL. In this case, one serial communication circuit 7 is sufficient for three motors, and wiring is simplified. In general, this portion of wiring is performed using a connector or a screw terminal after the FFU is installed in the field (clean room). However, since wiring is performed in the field, erroneous wiring and connection errors are likely to occur. Conventionally, such work is required in three places, but only one place is required. Therefore, the probability of erroneous wiring is reduced and the reliability of the wiring is improved.

When serial communication is performed, the communication speed decreases as the number of communication points increases. When the number of units is several thousand, the present invention uses only one set for the conventional method of using three sets of operation control circuits to check the total number of supervisory control computers. Time can be shortened to / 3.
In the above, an example in which the controller is integrally configured has been described. However, there are cases in which assembly and installation can be performed easily and inexpensively by standardizing with the same structure in the FFU.
FIG. 5 is a block diagram of a fifth embodiment of the present invention, in which each structure in the FFU is made the same and standardized.
In this configuration, the noise filter 6, the rectifier circuit unit 21, and the operation control circuit unit 22 provided in common in the controller 2 are collectively used as the rectifier / operation block 10, and an inverter provided for each fan / motor. The units 23A to 23C, the control circuits 24A to 24C, and the current / temperature detection units 25A to 25C are combined into motor drive blocks 11A to 11C.

As described above, the FFU can be configured by attaching a number of motor drive blocks corresponding to the number of fans and motors by separating the blocks provided in common and those provided for each motor into blocks. Therefore, for example, by configuring FFU casings of the same dimensions and installing FFUs by attaching motor drive blocks according to the number of fans and motors required, the FFU casings of the same dimensions are installed. , Handling becomes easy.
In the above embodiment, a three-phase AC power source is assumed as the power source, but the same effect can be expected even with one phase (single phase).
FIG. 6 shows an example of the basic configuration of a method for controlling the operation of three FFUs simultaneously. 6A is a plan view, and FIG. 6B is a cross-sectional view of the master unit.

  As shown in FIG. 6 (a), the master unit FFU-A having a controller CN and two slave units FFU-B and C are configured. The motor / fan MF of the parent device FFU-A is connected to a controller CN provided in the parent device via a screw terminal CO (or connector) and a motor cable A, and is operated while being controlled by the controller CN. Similarly, the motors / fans MF, MF of the slave units FFU-B, C are also connected to the controller CN provided in the master unit via screw terminals (or connectors) and motor cables B, C. It is operated while being controlled by. 6B, the box BX of the controller CN is attached to the upper part of the FFU casing K. In addition, a high performance filter FL is provided in the lower part of the FFU casing K, and when the fan F is driven by the motor M, the suction air flow sucked from the upper part is clean air flow to the lower part through the high performance filter FL. It is configured to be discharged as.

The configuration of the slave unit is only different from the master unit in that the controller BOX is not provided.
FIG. 7 shows an example of a clean room monitoring control system having a plurality of groups of FFUs configured as described above, and FIG. 8 shows an example of installation of FFUs in a clean room. 8A is a plan view of the clean room CR, and FIG. 8B is a cross-sectional view of the clean room CR.
In FIG. 7, a common controller CN is provided for the three FFUs, and the FFU communication lines L1 to L3 and the power lines PL1 to PL3 are connected to the common controllers CN, so that the wiring is reduced. You can see how it is. FIG. 8 shows an example in which 3 × 12 FFUs are arranged in areas 1 to 3, respectively. As shown in FIG. 8A, FFU communication lines L1 to L3 and power lines PL1 to PL3 By wiring as shown in the figure, it can be seen that the wiring is saved.

In the clean room CR, as shown in the cross-sectional view of FIG. 8B, 3 × 12 FFUs are arranged on the upper part, and the clean airflow through the high-performance filter FL of each FFU is applied to the grating (access) floor. It circulates through the cooling coil CC and the chemical filter CF, and is configured to return to each FFU.
In addition, although the main unit and the sub unit have one motor / fan installed in the FFU, the size of the FFU can be increased by providing a plurality of motors / fans.
FIG. 9 is a block diagram showing a sixth embodiment of the present invention. FIG. 9 shows an example in which four motors / fans are installed in one FFU. FIG. 9A is a plan view and FIG. 9B is a cross-sectional view. In FIG. 9, four motors / fans MF are installed in one FFU, and each motor / fan MF is connected to a controller CN as shown in FIG. Connect to and control.

In the example of FIGS. 7 and 8, for example, when three FFUs are operated as one set, when a stop command is given to any one FFU from the monitoring control side, the corresponding three FFUs are Back pressure generated by other FFUs operating in the same area from the time when operation was stopped (path pressure loss of circulating airflow: total value of passage loss of floor FL, cooling coil CC, chemical filter CF, duct base, etc. ) May cause the motor / fan to receive reverse force. Although this negative pressure value varies depending on the configuration of the clean room, it may exceed 100 Pa, and the reverse rotation speed may reach 1/3 to 1/2 of the positive rotation speed (operation rotation speed).
When an operation command is given from the monitoring control side in the above-described state, the three FFUs must start operation from reverse rotation to normal rotation simultaneously from the command time. At this time, it is generally required that the time required to reach a predetermined operation speed is within 60 seconds. According to the present invention, it is possible to sufficiently meet such a requirement by configuring as shown in FIG. 2, and it has been experimentally confirmed that it can be realized in about 40 seconds when the back pressure is 175 Pa.

The block diagram which shows 1st Embodiment of this invention The block diagram which shows 2nd Embodiment of this invention The block diagram which shows 3rd Embodiment of this invention The block diagram which shows 4th Embodiment of this invention The block diagram which shows 5th Embodiment of this invention Configuration diagram showing basic configuration example of FFU operation control Configuration diagram showing an example of an FFU monitoring control system Configuration diagram showing FFU installation example in a clean room The block diagram which shows 6th Embodiment of this invention Configuration diagram showing a conventional example of an FFU monitoring control system Configuration diagram showing a conventional example of motor control

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Power source, 2, CN ... Controller, 21 ... Rectifier circuit part, 22 ... Operation control circuit, 23A, 23B, 23C ... Inverter part, 24A, 24B, 24C ... Motor control circuit, 25A, 25B, 25C ... Motor current Temperature detector, 3A, 3B, 3C ... motor, 4A, 4B, 4C ... load, 5 ... position detector, 6 ... noise filter, 7 ... serial communication circuit, 10 ... rectification / operation block, 11A, 11B, 11C ... Motor drive block.

Claims (9)

  Each motor / fan drive circuit provided in a large number of fan filter units is provided corresponding to each motor / fan, respectively, a rectifier circuit for supplying power to the drive circuit, and operation stop of the motor / fan. An operation control circuit for performing speed setting / abnormality processing is provided in common for the plurality of drive circuits.   The drive circuit, the rectifier circuit, and the operation control circuit that are provided in common are mounted on a predetermined fan filter unit among the fan filter units that are installed in large numbers. The fan filter unit according to claim 1, wherein power is supplied from a corresponding drive circuit via a motor cable.   A plurality of motors / fans are provided in one fan filter unit, and a drive circuit for each motor / fan is provided corresponding to each motor / fan in the fan filter unit to supply power to the drive circuit. The fan filter unit is characterized in that a circuit and an operation control circuit that performs operation stop / speed setting / abnormality processing of the motor / fan are provided in common to the plurality of drive circuits in the fan filter unit.   The fan filter unit according to any one of claims 1 to 3, wherein the rectifier circuit and the operation control circuit are integrated.   The fan filter unit according to claim 4, wherein the drive circuit is added to form an integrated configuration.   6. The fan filter according to claim 1, wherein the drive circuit of each motor / fan includes an inverter unit, a motor control circuit unit, and a current / temperature detection unit of the motor / fan. unit.   The fan filter unit according to any one of claims 1 to 6, wherein the motor / fan is a synchronous motor or a DC brushless motor.   The fan filter according to any one of claims 1 to 7, wherein a serial communication circuit is provided in the operation control circuit, and external operation and external monitoring are enabled via the serial communication circuit. unit.   The fan filter unit according to any one of claims 1 to 8, wherein the operation control circuit is capable of individually setting a speed of each motor and fan.