KR19990082198A - Turbo machine drive device and its control method - Google Patents

Abstract

Since it is a dual inverter, it aims to simplify the supply and demand of signals to each other and to simplify the logic for complex supply and demand, thereby eliminating the external communication control unit.

The present invention is the first and second earth leakage breaker (ELB1, ELB2), inverter (INV1, INV2), electric motors (5-1, 5-2), pumps (4-1, 4-2) In the system, the inverters INV1 and INV2 are connected to signal lines for transmitting fault and operation status signals, and the signal lines of the sensor group for detecting a load state are directly connected to the inverters.

In this way, the system is simplified, small size, light weight and low cost are realized, and the number of parts is reduced, thereby improving reliability, without requiring a high communication circuit part externally.

Description

Turbo machine drive device and its control method

In turbomachines such as turbo type pumps and turbo type blowers, the water supply amount and the air flow rate are in operation speed, the water supply pressure and wind pressure are in power of the driving speed, and these outputs are proportional to the power of the driving speed. This means that the driving speed is also slowed down with the reduction of the load, and thus there is an advantage that energy saving can be achieved.

Conventionally, speed control is carried out using a plurality of inverters to maintain the discharge-side pressure of the plurality of turbo machines in a certain relation, and at the same time, operation order and number control of the plurality of inverters and turbo machines are performed.

Therefore, when the plurality of turbomachines are driven by a plurality of inverters to control the speed and the number of driving, the water supply amount, the air flow rate, the water supply pressure, and the wind pressure can be efficiently controlled in accordance with the load variation relatively easily. Accordingly, it is considered that speed control by the inverter will become more and more popular in the future.

Among these, the example which used an inverter for a water supply apparatus is demonstrated with reference to FIGS. 1 is a configuration diagram of a water supply device, 1 is a water drain pipe, 2-1 and 2-2 are drain pipe branch pipes, 3-1, 3-2, 3-3, 3-4 is a diaphragm valve, 4-1, 4-2 is a pump, 5-1 and 5-2 are electric motors, 6-1 and 6-2 are check valves, 7 is a water tank, 8 is a pressure tank with air reservoir inside, and 9 and 10 are pump suction side And an pressure sensor for detecting the pressure on the pump discharge side, and emits an electrical signal corresponding to the pressure of the detection section. FS1 and FS2 are flow switches that are turned on at a smaller quantity QS or less shown in FIGS. 2 and 3 to be described later. The CNU is a control device including an inverter (INV1, INV2) for shifting the motors 5-1, 5-2 so as to be shiftable, a leakage circuit breaker (ELB1, ELB2) for protecting a short circuit, a relay circuit portion (R), and It consists of a controller CU. The relay circuit R includes a transformer TR, a stabilized power supply Z, relays 52X1 and 52X2, and an interface I / O of the controller CU.

The controller CU is an A / D converter for converting signals (analogs) from the arithmetic processing unit CPU (hereinafter referred to as CPU), pressure sensors 9 and 10 into digital signals, and inverters INV1 and INV2. Interface for driving the above-mentioned relays 52X1 and 52X2, a power supply terminal E for supplying power to the controller CU, and a D / A converter that commands the speed command signals N1 and N2 desired by the water supply system. An output port PIO-1 is provided for transmitting the signal S4 to the I / O. Similarly, the input ports PIO-2 and the ground fault breakers ELB1 and ELB2 for reading the set values set by the setting means C so as to operate according to the operating characteristics of the pump shown in Figs. Input port (PIO-3) for reading the states of the contacts (ELBAL1, ELBAL2) and the inverters (INV1, INV2) operating when tripped due to the short circuit, etc. Equipped with. That is, the CPU executes the instruction and its control to stop the pump and switch to the other pump which is at rest according to their failure condition.

Fig. 2 is an operation characteristic diagram when one pump alone or two pumps are alternately operated by the water supply apparatus described above, and the pressure H on the vertical axis and the quantity Q on the horizontal axis are shown. Curve A is the Q-H performance curve when the pump is driven by the inverter at the operating speed N3, that is, at 100% operating speed. Similarly, curves B, C, and D are Q-H performance curves when the pump was driven at the operating speeds of N2, N1, and N0, respectively. Further, the curve F is a pipe resistance curve. For example, when the water supply amount is changed from the water supply Q1 to the water supply Q0, the water supply at the discharge side of the pump at the pressure along this curve F is used. It shows that the water supply system can obtain a desired pressure. The inverters INV1 and INV2 described above are externally set by the consoles CONS1 and CONS2 under which conditions, for example, acceleration and deceleration times and V / F (output voltage and output frequency characteristics, etc.) are rotated. That is, the water supply device drives the pump along O3 → O2 → O1 → O0 on the curve F.

Then, when the earth leakage breakers ELB1 and ELB2 are turned on and the control power breaker CB is turned on, the power supply of the control unit CU is established and the CPU is based on a program stored in the memory M in advance. By performing initial setting to read the setting information from the setting means C, read the state of the inverter and the ground fault breaker (fault-free state) from the input port PIO-3, and the signals of the pressure sensors 9 and 10. Is read via the A / D converter. In addition, the pipeline resistance curve F is stored in advance, and the water supply pressure is to change along this resistance curve F in response to a change in the operating speed when the load state changes. This completes the preparation for operation. When water is used in this state, the water supply pressure decreases, and when the water pressure drops below the starting pressure HON shown in FIG. 2, the CPU passes the relay 52X1 to the interface I / O via the output port PIO-1. While outputting a convenient signal, a signal of the driving speed N1 is output to the inverter INV1 via the D / A converter. Inverter INV1 is thereby started to drive motor 5-1. After the operation, the water supply pressure is controlled based on the signal of the pressure sensor 10 so as to be on the curve F. FIG. When the pumping condition is established because the quantity of use decreases, the CPU releases the convenience signal of the relay 52X1 currently output and the speed command signal N1 to the inverter INV1. This causes the pump 4-1 to stop. When the water is used again to be below the water supply pressure HON and the starting condition is established, the relay 52X2 and the operating speed N2 are signaled, and this time, the other inverter INV2 and the motor 5-2 are turned on. It drives and drives the pump 4-2. Thereafter, similarly, switching control is performed to perform alternate driving.

3 is a characteristic diagram when two pumps are operated in parallel, and the same reference numerals as those in FIG. 2 have the same meaning. That is, as shown in Fig. 2, two pumps are operated alternately, and when the number of uses increases, the pumps 4-1 and 4-2 are operated simultaneously. When the quantity used exceeds Q3, the operating speed N3 is the highest speed, so the water supply capacity is insufficient and the water supply pressure drops to HL. As a result, the CPU issues signals of the relays 52X1 and 52X2 and the speeds N1 and N2 together. In this way, the inverters INV1 and INV2 and the motors 5-1 and 5-2 are operated at the same time, and the pumps 4-1 and 4-2 are operated in parallel. After the operation, control is performed based on the signal of the pressure sensor 10 so that the water supply pressure is on the curve F. As shown in FIG.

In Fig. 3, when the use quantity of water decreases, the operating speed becomes N4 + N3, and the water supply pressure becomes HH, one of the two stops to operate alone.

As these well-known examples, Unexamined-Japanese-Patent No. 5-231332 is referred.

Thus, in order to drive two inverters conventionally, the main controller which controls an inverter above this was needed.

In the above prior art, there are the following problems. In other words,

(1) In the conventional system, even if two inverters are normal, if the main control device does not operate abnormally, there is a problem that the system goes down and becomes the singular.

(2) In the case of configuring a system with dual inverters, since each has a control function, even if one is down due to failure, the other one can perform backup operation. However, since the respective control functions are provided, it is difficult to transfer the control states of each other. In order to alternately drive and parallel drive the inverters, it is necessary to interlock with each other from the outside of the inverter, detect these states, and command the operation. In addition, the system has a complicated control logic due to the large number of interlock signals.

The present invention relates to a plurality of inverters and applications thereof for driving a plurality of turbomachines.

1 is a block diagram of a conventional turbomachine driving device.

2 is an operating characteristic diagram when the pump is operated alone or alternately.

Fig. 3 is an operating characteristic diagram at the time of parallel operation of two pumps.

4 is an overall configuration diagram of a system illustrating a water supply apparatus as a turbomachine according to the present invention.

5 is a detailed view of the terminal and the supply and demand signal of the dual inverter according to the present invention.

Fig. 6 is a time chart showing the procedure of power supply increase processing of the apparatus shown in Fig. 4 according to the present invention.

FIG. 7 is a time chart showing a method for controlling parallel operation of the apparatus shown in FIG. 4 according to the present invention.

Fig. 8 is a flowchart for realizing the processing of Figs. 6 and 7 according to the present invention.

SUMMARY OF THE INVENTION The present invention has been made in view of the above point, and an object thereof is to obtain a dual inverter and its application device, which can realize small size, light weight and low cost, since external peripheral devices are not required and signal supply can be easily performed. .

In order to achieve the above object, the present invention provides two turbo machines, two inverters each for driving the turbo machine, and a plurality of sensors for detecting a load state of the turbo machine to perform speed control of the turbo machine. In the turbomachine driving apparatus, the inverters are connected by four kinds of supply and demand signals indicating an operating state with each other, and the two inverters take in the plurality of sensor signals in common, and the two inverters supply and receive each other. A turbomachine driving device for controlling the speed of the turbomachine while interlocking by a signal, or two turbomachineries, two inverters each driving the turbomachine, and the load state of the turbomachinery And a plurality of sensors for detecting and outputting the detection signal in common to the inverter. In the turbomachine driving apparatus which performs a fishing, when the sensor detects the predetermined start state, the inverter set as a priority is started, and when the said priority detects a parallel operation start condition, it stops from the inverter which drives the said priority. The starter is started by applying a start request to the inverter of the inverter, and the priority is controlled so that the discharge pressure is controlled at the highest target pressure on the discharge side during one operation until the successor driven by the inverter started in parallel becomes a constant state of parallelism. The shifting operation is carried out by an inverter, and when the successor in parallel operation is operated in parallel constant speed state, the shifting operation is performed so that the estimated end pressure constant control is performed according to the discharge target pressure at the time of two parallel operation, and the underload predetermined by the sensor When the state is detected, the priority unit is stopped. The control method of the beam machine drive device.

The outline | summary of embodiment of this invention is demonstrated as follows.

It is also possible to combine the signal contents necessary for the signal supply of the dedicated inverter with the minimum possible. Conventionally, the I / O port provided by a general purpose inverter is used as it is. By detecting only pumps, stops, and parallel operation start and release detection with only the preceding inverters, the simplified supply and demand signals between the mutual inverters are simplified, and the mutual interlock signals are minimized, preferably with two outputs and two input signals. Exchange signals with each other. Then, these inverters set the priority of how to operate the inverter by setting unit in advance or which of the inverters is operated first by setting the operation pattern of the load. In this way, alternating and parallel operation, retries in case of abnormality, and backup operation are performed. The earth leakage breaker interrupts the main circuit by performing short circuit protection of the main circuit and earth leakage protection of the secondary side. The inverter drives the turbomachine and is composed of a dual system, and each signal of the pressure sensor for detecting the load state, the under-load state detection means, and the suction side pressure sensor is directly taken in parallel at the same level. Inverters are assembled with software programs for operating a microcomputer, each of which controls a control method and procedure in advance, and are operated according to an input signal such as a sensor. When the earth leakage breaker is turned on at the beginning of use, the power supply to both inverters is established, and the one set externally as the priority device waits for operation. When the pressure sensor which detects the load state detects a preset starting pressure, the inverter on the standby side is started. The same inverter stops when the sensor detecting the underload condition detects this and the preset stop condition is established, and the idle inverter becomes operational by the stop signal of the preceding device, and starts and stops as described above. Is done. When the pressure sensor for detecting the load state detects a preset parallel operation pressure state, the inverter during operation outputs a parallel operation request signal to the inverter during idle, and the inverter during idle is parallel from the state in which it can operate. Drive. In case of tripping of the earth leakage breaker and tripping of the inverter, this state is transmitted to each other by the signal line connecting the two inverters, and switching from the stop of the error occurrence side to the operation of the normal side, the abnormal side generates an internal signal and restarts. Make an attempt. On the other hand of the inverter, this state is indicated by an error code on the display unit, and an external signal is issued. In addition, the display unit is used to display pressure, current, voltage, and frequency values.

EMBODIMENT OF THE INVENTION Hereinafter, one Example of this invention is described in detail using drawing.

FIG. 4 is an overall configuration diagram showing an embodiment in which the present invention is applied to a water supply apparatus, and the portions denoted by the same reference numerals as those of FIG. 1 cited in the prior art description are the same, and thus description thereof will be omitted.

In the same figure, the control device CNU is provided with earth leakage breakers ELB1, ELB2, inverters INV1, INV2, and noise filters ZCL0, ZCL1, ZCL2. This is caused by assembling the relay circuit portion R and the control device (hardware and software) CU shown in Fig. 1 to the inverters INV1 and INV2 described above.

That is, these inverters INV1 and INV2 output the trip signal AL of the earth leakage breakers ELB1 and ELB2 as ELB trip signals to the external terminal of the control panel via the signal lines S1 and S2.

The signal FS1b or FS2b of the flow switch FS1 or FS2 is input to the terminal DI4-COM via the signal line S4 or S5, and the signals of the pressure sensors 9 and 10 are signal lines S6 and S7, respectively. Input to terminals AN0, AN1, L via In addition, since the pressure sensors 9 and 10 are commonly used for the inverters INV1 and INV2, the pressure sensors 9 and 10 are connected to each other by the signal line S8.

The terminals DI1, DI2, DO1, DO2 of the inverters INV1, INV2 are connected by a signal line S3 to exchange signals such as an operation state, a failure state, an operation request, and the like. The DI3 terminal is the selector signal for the priority and the inverter INV1 is shorted to COM.

The signal lines S9 and S10 are signals for outputting faults of the inverters INV1 and INV2 to a central monitoring panel or the like.

5 and Table 1 show the supply and demand signals S3 of the inverters INV1 and INV2 in detail. In addition, Table 1 is a symbol table which shows the output state and control state of the supply-demand signal of the dual inverter by this invention.

The interlock signals of the inverter 1 and the inverter 2 are each provided with two outputs and two inputs, and four types of states can be notified to the counterpart by turning on / off this two-bit signal.

In Fig. 5, when the states of the outputs DO1 and DO2 are represented by the states A to D shown in Table 1, the state A is "Parallel" if the DO1 and DO2 are both on and the pumps themselves are operating in advance. Start request "signal.

Statue of god Terminals Contents DO1 DO2 A ON ON Parallel start request (at the leading edge) Parallel highest speed status (at the trailing edge) B ON OFF During auto shift (parallel) operation C OFF ON Auto shift (parallel) waiting D OFF OFF Power off, Automatic single failure stopping, Manual

If it is a subsequent pump, it displays the "Parallel Constant" signal that is output when the preset maximum constant is reached. This occurs when both sides are in automatic mode and parallel operation is set. State (B) represents a state of "automatic shift (parallel) operation" with DO1 on and DO2 off. State (C) represents a state of "automatic standby (parallel) waiting" with DO1 off and DO2 on. State (D) is a state in which both DO1 and DO2 are in off state, indicating "automatic alone operation mode", "manual mode", "faulty stopping" or "shutting down power", and the state itself is operating alone. Or it shows the state which cannot drive alternately and in parallel. The above signal can realize supply and demand such as alternating, parallel, backup operation in case of failure.

Supply and reception of the signal will be described in detail with reference to the time charts of FIGS. 6 and 7. First, the alternating operation after power supply surge and operation at abnormal time will be described using the time chart of FIG. At the time 1 of the same figure, the power supply of the inverter 1 rises rapidly and the state changes from D to C. FIG. At this time, the counterpart inverter 2 remains in the D state because the power supply has not risen yet. Since only the inverter 1 can pump operation, the inverter 1 automatically operates by single operation. At time 2, inverter 1 detects and operates the pump start condition. At this time, the inverter 1 outputs the B state from the C state to display that it is in operation. At the time 3, the pump stop condition is detected and the inverter 1 stops and outputs the C state from the B state. Next, since the power supply of the inverter 2 rapidly rises at the time 4, the inverter 2 outputs the C state from the D state. Inverter 1 is shifted to parallel or parallel operation because the inverter 2 is in the C state, so that alternating or parallel operation is possible. At time 5, the pump starting condition is detected. At this time, since both the inverter 1 and the inverter 2 take in the signal of the same sensor, the starting condition is established at the same time. However, since the inverter 1 is set as a priority, the inverter 1 is started first, and from the state C Output B Inverter 2 is already in the alternating mode when the power supply suddenly rises because the inverter 1 is in the C state. However, the inverter 2 is delayed to operate even when the starter condition is detected. Since 1) operates first to output the B state, the inverter 2 stops operating. By staggering the timing in this manner, starting at the same time is prevented. After the time 5, the preceding and subsequent stages are assured, so the start condition is established at the time 6 and the start is established at the time 6, and the inverter 2 is operated. After that, shift driving is similarly performed. When a failure occurs in the inverter 1 at the time 10, the state of the inverter 1 changes from B to D. At this time, the inverter 2 which is stopped determines that the state of the inverter 1 changes from B to D, and determines that the failure has occurred. In addition, since the start condition is detected, operation is started to output the state from C to B. When the inverter 2 recovers the failure of the inverter 1 at the time 11 during operation, the inverter 1 outputs the state from D to C, and thus the normal alternate operation mode becomes possible, thus becoming a standby state. At time 12, inverter 2 stops, and after time 13, normal alternating operation is performed.

Next, the parallel operation operation will be described using the time chart of FIG. At the time 1 of FIG. 6, the inverter is in the same state as the time 4 of FIG. 6, and when the starting condition is detected at the time 2 of FIG. 6, the inverter is set as a priority as in the time 5 of FIG. 6. (1) first starts driving. When the parallel start condition is satisfied at time 3, the inverter 1 outputs a " parallel start request " A to the inverter 2 when the inverter C is in a state C capable of automatic operation. The inverter 2 confirms that the inverter 1 outputs the state A, and starts operation. At this time, the inverter 2 outputs B from the state C and gradually increases the speed to the speed (preferably the MAX speed) set. Inverter 1 performs the shift operation from time 3 to time 4 so that the discharge pressure becomes constant with a target value of O3 (the point of the highest target pressure on the first discharge side) in the F curve in FIG. At time 4, when the inverter 2 reaches the set speed, the inverter 2 outputs that the state becomes "parallel constant speed state" from state B to state A. When the inverter 1 confirms the state A of the inverter 2, the inverter 1 performs a shift operation based on the estimated end pressure constant control according to the change in the amount of water to a target value on the O3 to O5 of the F curve in FIG. When the inverter 1 detects the parallel release condition at time 5, the pump 4-1 is stopped and the state is output from A to C. The inverter 2 confirms that the inverter 1 is in the C state, and shifts on the basis of the estimated end pressure constant control in accordance with the change in the amount of water from the constant speed operation to the target value on the O0 to O3 of the F curve in FIG. Is done. In this way, the above-described signal supply and reception can detect the starting, parallel introduction, parallel releasing, and stopping conditions only with the preceding device, thereby enabling unification of control. Moreover, this method can suppress the pressure fluctuation of parallel starting small, and can switch a driver by parallel.

Next, a flow for realizing the control as in the time charts of FIGS. 6 and 7 will be described using the flowchart of FIG. "○" in the drawing indicates a symbol that outputs its own state. &Quot; □ " is a symbol indicating which state the other party's state has transitioned to. In reference numeral 800, the priority is determined in advance by an external terminal of the inverter. When the power is turned on in 801, in 802, the priority is forcibly set to the preceding device and the non-priority to the subsequent device. In 803, the process is in a waiting state until the start condition is established. If the start condition is established, the process proceeds to 804, where the process is divided by setting whether it is a predecessor or a successor.

In the case of the preceding stage, starting is started at 805. At 806, it is checked whether or not it is a failure. If it is normal, at 807, the terminal pressure according to the change in the quantity of water is a target value of the phase O0 to O3 of the F curve in FIG. After the constant control is performed, an under-quantity condition is checked at 808 and the condition is established. In the case of stopping, in 822, the setting is switched from the preceding machine to the successor to prepare for the shift operation. When the parallel condition is checked at 810 without detecting the under-quantity condition at 808, if the partner state is checked at 811 and is "automatic standby", the parallel parallel request is output at 812 by outputting the "parallel start request" to the counterpart. The discharge side is confirmed at 813, and the discharge pressure is set at 814 to 816 as the target value of the F curve O3 (point of the highest target pressure on the first discharge side) in FIG. This is controlled constantly. When it is confirmed that the opposite side state is a "parallel constant state", the second terminal pressure in accordance with the change in the water quantity is controlled constantly at the target value of the O3 to O5 of the F curve in FIG. The parallel release condition is checked at 820, and if the condition is satisfied, the preceding device is stopped at 821. In the meantime, when the following machine is fixedly stopped at 817 to 820, the process returns to 807, where only one end pressure is constantly controlled. In 819, the failure state of the preceding device (self) is checked. In the case where the preceding device stops due to a failure or parallel release, in step 822, the setting is switched from the preceding device to the successor in preparation for the next shift operation, similarly to the stop of detecting the excessive quantity. The above is the process as a preceding device for realizing the time chart of FIG. 6 and FIG.

Next, when it is set as a successor in 804 with respect to the processing of the subsequent machine, it is checked in 823 whether the preceding device of the other party is operated or operated. In operation, it is checked whether there is a parallel request at 824, and when there is a request, a parallel start is made at 826. If it starts, it operates at a constant speed until the preceding unit stops at 829. When it starts, it starts to accelerate, and when it reaches the preset speed in 828, it informs the predecessor. When the follower stops at 829, the setting of the follower is switched to the predecessor at 830. Subsequently, the process is shifted to 806 as the predecessor, and end pressure constant control is performed. In the case where the preceding device stops due to a failure or under-quantity detection in the parallel request waiting state (automatic waiting) in 823 to 824, the setting of the successor to the preceding device is made in 825 and the next start is prepared. The above is the process as a follower for realizing the time chart of FIG. 6 and FIG.

According to the above embodiment, it consists of two turbomachines and two inverters for driving them one by one, and these inverters are equipped with a microcomputer and have a status display section and a control constant setting section for detecting a load state of the turbomachinery. It takes in a signal of the sensor group and is set to operate in advance based on the load state to the control constant setting unit, and is connected by the minimum signal line which displays the operation state and the failure state to each other, and the two inverters interlock with each other. In the turbomachine drive device which performs constant end pressure constant control while performing parallel start, in the case of parallel start control, a "parallel start request" signal is set in the supply and demand signal, and when the preceding device detects the parallel operation start condition, the starter inverter requests the parallel start operation. Outputs a signal to start the idle inverter. Outputs a "Parallel" signal and gradually increases the speed with a preset acceleration to reach a predetermined constant speed (preferably the highest speed) and outputs a "parallel constant speed" signal to the preceding device. The shift operation control is carried out so that the target pressure on the first discharge side becomes constant from the time of automatic operation "to the" parallel constant speed state ", and the predecessor is set to the second discharge side target pressure when the parallel gear started in parallel is operated in the" parallel constant state "operation. Therefore, the shifting operation is performed so that the estimated end pressure constant control is performed, and in the control at the time of parallel release, the follower performs the constant speed operation during the parallel operation. The parallel release condition set in advance can be detected by the predecessor. When the minimum speed is reached, the pressure is monitored and when the stop pressure is reached, the preceding device is stopped and output to the follower.When the follower in constant speed receives the "Automatic Standby" signal, it is determined according to the preset target pressure on the first discharge side from the constant speed operation. Since the variable speed operation is performed so that the estimated end pressure constant control can be performed, it becomes possible to detect the start and stop conditions of parallel operation with only one preceding inverter, even with a dual inverter.

In the control of the transient state during parallel start, when the preceding device detects the parallel operation start condition, the starter applies a start request to the idle inverter to start the idle inverter, until the inverter starts the parallel constant constant state. The speed change operation is performed so that the discharge pressure is controlled at the highest target pressure on the first discharge side, and the predecessor has a constant terminal pressure constant control while varying the discharge target pressure according to the target discharge pressure on the second generation when the follower started in parallel is operated in parallel constant speed. Since the shift operation is performed as much as possible, it is possible to perform stable pressure control by suppressing divergence of the control state by not updating the target pressure on the discharge side of the preceding stage until the successor is stable when the transient state is unstable during parallel startup. have.

In addition, the signal connecting two inverters includes the one stopped due to a failure, and the signal is displayed in the same state as the output of the inverter's power interruption, thereby avoiding a fault signal without separately inputting the trip signal of the ground fault breaker. It became possible.

In addition, a mode switch is provided to connect the manual-switching-automatic signal to the external input terminals of the two inverters, and in FIG. 4, DI5 is turned on and DI6 is turned off, thereby turning "auto", DI5 off, and DI6 on. This makes it possible to make the control states of the two inverters the same by giving meaning to "switch" by turning both "manual", DI5 and DI6 off or on.

In addition, by shorting any one external input terminal of one of the two inverters to a "priority", for example, the malfunction of simultaneous operation at the time of power-on or power failure recovery can be prevented. This makes it possible to easily set the priority device.

Further, since the system of the complete double system is constituted by the first system and the second system, fault backup is taken, and the reliability can be further improved.

In addition, the inverter is equipped with a program in advance so as to operate in accordance with the load operation pattern, and is set by the setting unit of the inverter to operate based on this, and is set as a priority when the load state detecting means detects the starting pressure. Is started, and the underload detection means detects the underload condition and stops when the stop condition is established, so the supply and demand of the two inverters does not require an external communication circuit unit and complicated supply and demand logic, such as alternating operation or alternating Since the parallel operation can be performed, the control device can be simplified, and the weight and size can be reduced at the same time. And since the number of parts points is reduced, reliability improves. In addition, short circuits and short circuits in the main circuit are prevented by an earth leakage breaker, and the inverter itself monitors a fault condition on the other side of the load by a change in the internal state amount of the inverter. Since the starter can be externally set in advance by the inverter and the start timings are staggered, the operation sequence is not disturbed (when power failure returns, etc.).

In addition, since a failure retry operation is added, the failure state can be reliably detected.

Moreover, since the pressure sensor which detects a load state and the pressure sensor which detects a suction side pressure can be shared by two inverters, it becomes simple and low price.

According to the present invention, since the two inverters can be operated in conjunction with the signal exchange between the inverters with the minimum signal supply and demand, the externally mounted control device is unnecessary, so that the turbo machine driving device can be made simple and light in weight and low in cost. And its application.

Claims (13)

A turbomachine driving apparatus for controlling the speed of the turbomachine, comprising at least two turbomachines, at least two inverters respectively driving the turbomachine, and a plurality of sensors for detecting a load state of the turbomachine, wherein the inverter Are connected by at least four types of supply and demand signals indicative of the operation state of each other, at least the two inverters take in common the plurality of sensor signals, and at least the two inverters stop at least by the supply and demand signal from each other. And controlling the speed of the turbo machine by judging single operation, alternating operation, or parallel operation. 2. The turbomachine drive apparatus according to claim 1, wherein the turbomachine is a turbo type pump. The turbomachine driving apparatus according to claim 1, wherein the turbomachine is a turbo blower. The turbomachine driving apparatus according to claim 1, wherein the four types of supply and demand signals are received and received between the inverters as two output signals and two input signals. The four kinds of supply and demand signals include: a parallel start request signal for applying a start request to one of the inverters during operation from one of the inverters during operation to start the inverter during idle operation; A signal during the automatic operation outputted from the other inverter to the one inverter until the predetermined constant speed after the other inverter is started after the one inverter of A parallel constant speed signal outputted from the other inverter to the one inverter when operating at a constant speed, and another inverter from the inverter in the stopped state when one or both of the one or the other inverter is stopped Turbo machine driving device, characterized in that consisting of a signal during automatic stop output. 6. The turbo according to claim 5, wherein the auto-stop signal includes a signal indicating that the inverter is stopped due to a failure and a signal indicating that the inverter is stopped due to a power failure as a signal in the same state. Mechanical drive. 6. The discharge-side target of the turbomachine of claim 5, wherein the inverter is driven by the one inverter until the other inverter, which is subsequently started in parallel, sends the parallel steady state signal after the other inverter sends the automatic driving signal. A shift operation means for controlling the pressure to be constant and the turbo machine is shifted so that the estimated end pressure constant control is performed according to the discharge side target pressure during two parallel operations when the other inverter sends the parallel constant speed status signal. And a preset speed based on the rotational speed and the load side pressure of the turbo machine in which the discharge side pressure is constantly shifted to the other inverter during the parallel operation of the turbo machine driven by the other inverter in the constant speed operation. Means for detecting a release condition and the detection of the parallel release condition; Means for outputting the auto-stop signal to one inverter, and the other inverter estimates according to the discharge-side target pressure during one preset operation instead of the constant speed operation control when receiving the auto-stop signal during parallel operation. And a means for shifting in such a manner that constant pressure is controlled. The method according to claim 1, wherein the manual-switching-automatic mode switch is commonly connected to the external input terminals of the two inverters, and the input terminal is a mode switching terminal so that the mode state of the two inverters is always maintained at the same level. A turbomachine drive device characterized by being easily realized. The inverter according to claim 1, wherein an external input terminal for determining which of the two inverters is preferentially operated when the sensor detects a predetermined starting state is provided in the inverter, respectively, and the terminal is short-circuited. A turbomachine driving device comprising a turbocharger driven by an inverter as a priority. The turbomachine driving apparatus according to claim 1, wherein the system of the dual system is configured by the first system and the second system. At least two turbomachines, at least two inverters for driving the turbomachines per unit, and a plurality of sensors for detecting a load state of the turbomachine and outputting the detection signal to the inverter in common; In a control method of a turbomachine driving device which performs control, an inverter set as a priority is started when the sensor detects a predetermined start state, and an inverter which drives the priority when the priority detects a parallel operation start condition. The start-up request is applied to the idle inverter from the standstill, and the follower driven by the idle inverter is started, and the prioritizer is discharged at the maximum target pressure during one operation until the successor driven by the parallel-inverted inverter becomes the parallel constant speed state. Shifting operation with an inverter so that constant discharge pressure is controlled, When the subsequent starter in parallel operation is operated in parallel constant speed state, the shift operation is performed so that the estimated end pressure constant control is performed according to the discharge side target pressure during two parallel operation, and the parallel release condition is based on the detection signal of the sensor during parallel operation. Is detected, the operation of the priority device is stopped and at the same time, the priority device is set as a successor or the successor as a preceding device, and when the sensor detects a predetermined underload condition, the preceding device is stopped and the relationship between the preceding device and the subsequent device is detected. The control method of the turbomachine driving device, characterized in that the replacement input. Two turbomachines, two inverters for driving the turbomachines one by one, and a plurality of sensors for detecting a load state of the turbomachine and outputting the detection signal in common to the inverters to control the turbomachine. In the control method of a turbomachine driving device performed, when only one inverter of the two is in operation and the other inverter is idle, the inverter in operation is set as a predecessor. The follower driven by the idle inverter is started by applying a start request from the driven inverter to the idle inverter. The shifting operation is performed so that the discharge pressure is constant, and the predecessor is started in parallel and the successor is parallel. When the constant speed operation is performed, the shift operation is performed so that the estimated end pressure constant control is performed according to the discharge target pressure in the two parallel operation. When the parallel release condition is detected based on the detection signal of the sensor during the parallel operation, the preceding device operates. And when the relationship between the preceding and succeeding devices is stopped, and the sensor detects a predetermined underload condition, the inverter is set to stop and the relationship between the preceding and succeeding devices is inputted. Control method of the turbomachine drive unit. In a turbomachine driving apparatus comprising a plurality of turbomachines, a plurality of inverters respectively driving the turbomachines, and a plurality of sensors for detecting a load state of the turbomachine, to control the speed of the turbomachine. Connected by a plurality of types of supply and demand signals indicating an operation state, the plurality of inverters take in common the plurality of sensor signals, and the plurality of inverters are at least stopped by the supply and demand signal, and at least the operation is stopped. The turbomachine drive device characterized in that speed control of the turbomachine is performed by judging operation and parallel operation.