JP3472522B2 - Multiple motor control device, power conversion device, inverter module, converter module - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control device for simultaneously controlling a plurality of motors by using a converter and an inverter.

[0002]

2. Description of the Related Art As a conventional motor control device, an inverter is used to convert an input current into a sinusoidal alternating current, and at the same time, P
A WM (Pulse Width Modulation) control is used to control the motor speed, and a converter (AC-DC conversion circuit) that serves as a power supply circuit for the inverter also uses a boost chopper that can improve the power factor of the power supply to generate a DC voltage. PAM
(Pulse Amplitude Modulation) control to control the motor speed is known (for example, Japanese Patent Laid-Open No. 61-
10968, JP-A-59-198897,
JP-A-59-181973).

In this system, the motor speed is controlled by PWM control at low speed, and the motor speed is controlled by DC voltage control (PAM control) of the power supply circuit at high speed. Further, there are a method of switching to PAM control, a case of changing the duty ratio of the motor drive circuit to 100%, a method of maintaining the duty ratio at the time of switching, and a method of setting a fixed duty ratio pattern. .

A converter 1 for converting alternating current into direct current.
As an inverter device in which a plurality of inverters having a motor rotation speed control function are connected to a stand, there is disclosed in
There are those described in Japanese Patent Laid-Open No. 155283 and Japanese Patent Laid-Open No. 10-225163.

Among these, in the device disclosed in Japanese Patent Application Laid-Open No. 10-155283, a converter having a rectifier circuit and inrush current prevention integrated therein, a control circuit for controlling the rotation speed of the motor, and a signal exchange with the outside. The converter modules are shared by connecting each inverter module having an interface circuit to be modularized and connecting a plurality of inverter modules to one converter module.

In Japanese Unexamined Patent Publication No. 10-225163, a converter having a DC voltage control function is connected to a plurality of inverters capable of vector control of an induction motor, and the induction motor is rotated for a certain period of time at or below a command rotation speed. if you did this,
A technique for preventing burnout of the induction motor by lowering the DC voltage command of the converter is disclosed.

[0007]

In the above-mentioned conventional technique, the method of using the PWM control and the PAM control together uses one converter and one inverter. Considering the control of a plurality of motors using the above technique, as shown in FIG. 4, a motor control device (1
A plurality of devices each having a converter and an inverter of 1) are prepared, and these motor control devices are connected to a power source.

According to such a conventional system, a system using hundreds or thousands of motor control devices (such a system is realized in a system in which the output of each motor control device is relatively small). Therefore, the number of converters that will be DC power supply circuits is required, which increases the cost. Further, there is a fixed loss of the DC power supply circuit itself (a loss that occurs regardless of the magnitude of the output), which lowers the system efficiency.

Japanese Unexamined Patent Publication (Kokai) No. 10-155283 discloses a technique in which a converter and an inverter are modularized, and a plurality of inverter modules are connected to one converter module to share the converter module. However, the inverter module and the converter module operate independently, and the fact that the inverter module and the converter module cooperate to control the rotation of the motor is not considered.

The interface circuit built in the inverter module is a terminal for rewriting the speed command and the memory to the inverter control circuit, and exchanges the internal information of the inverter and the like with the host control device and the converter. No technology has been disclosed that does not include a communication means and that improves the motor control performance by such communication.

The contents described in Japanese Patent Application Laid-Open No. 10-225163 are contents in which a plurality of inverters detect information on the number of revolutions of a motor connected to each inverter, and the control state is changed according to the information. The purpose is to prevent burning of the steel.

Specifically, when the rotation speed of the motor is lower than the rotation speed command for a certain period of time, the DC voltage command is switched and lowered to prevent burnout.

Also in this conventional example, the rotation speed control of the motor is performed by the inverter, and the converter is used as a power supply source to the inverter. Therefore, there is no idea of controlling the rotation speed by the converter.

That is, these prior arts do not consider PAM control of a plurality of connected motors, and cannot always supply the DC voltage desired by the inverter.

An object of the present invention is to provide a system in which a plurality of motor drive circuits (inverters) are connected to a single power supply circuit (converter), and even a single converter has status signals of a plurality of inverters (motor internal information). In view of the above, the PAM control of the converter is made possible by totally considering these status signals, and a motor control device for efficiently controlling a plurality of motors is provided.

Another object of the present invention is to provide a motor control device that enables power control and high-efficiency operation of the entire system by connecting a power supply circuit and a plurality of motor drive circuits through communication means such as a network.

[0017]

In order to achieve the above object, basically, the following means for solving the problems is proposed.

That is, a plurality of inverters for controlling the rotation speed of a motor are connected to one converter capable of controlling a DC voltage, and the speed control (PWM control) of each motor is performed by each inverter. The internal speed of the motor and the motor load, etc. (inverter status signal) is captured via communication means, and the DC voltage of the converter is controlled as necessary based on this status signal to control the rotation speed of multiple motors. Was set to be controllable (PAM control).

Further, the converter or the inverter is provided with communication means, the upper control device for collectively controlling the detected values detected inside each is provided, and the device for controlling the converter or the inverter according to the control signal from the upper control device. To propose.

Further, a module in which the inverter or converter is provided with communication means for communicating with each other through a network, and the inverter or converter and the communication means are integrated is proposed.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an overall configuration diagram of a motor control device according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 is a converter for converting an AC power supply into a DC power supply, which is a step-up chopper type circuit for simultaneously improving the power factor of the power supply and controlling the DC voltage.

A plurality of inverters 2, 4 and 6 capable of controlling the rotation speed of the motor are connected to the converter 1 through DC power supply lines. To each of the inverters 2, 4 and 6, motors 3, 5 and 7 to be drive-controlled (motors can be used for various purposes, but here, compressors are shown as examples) are connected. The rotation speed of the motor is controlled by PWM control by each corresponding inverter.

This converter 1 and a plurality of inverters 2,
4, 6 and the control circuit 8 are connected via a network (internal network).

The control circuit 8 outputs a DC voltage command value to the converter 1 via the network, and the inverter 2
Output the rotation speed command value (speed command value) to 4 and 6, and
It has a calculation function of inputting the DC voltage value of the converter and the status signal of the inverter (for example, input current value, inverter duty ratio) and calculating the DC voltage value based on the input.

The control circuit 8 is also connected to an external network so that the speed command of the motor can be set and changed from the outside.

FIG. 2 shows a circuit configuration of the converter 1.

The converter 1 controls the switching operation of the full-wave rectifier circuit 10, the step-up chopper circuit 11, the smoothing capacitor 12, and the step-up chopper circuit in order to convert the AC power supply into the DC power, thereby improving the power factor of the power supply. At the same time, it is composed of a converter control circuit 13 for controlling the DC voltage to a predetermined value and a communication circuit 14 for communicating with the control circuit 8 via a network. The communication circuit 14 is a signal conversion circuit for exchanging signals between the converter control circuit 13 and the control circuit 8 above it.

FIG. 3 shows the circuit configuration of the inverters 2, 4, and 6.

The inverters 2, 4 and 6 have an inverter main circuit 21 composed of a switching element and a diode, and a switching element P which is arranged according to the rotor positions of the motors 3, 5 and 7.
The inverter control circuit 22 that drives the WM signal to control the rotation speed of the motor communicates with the control circuit 8 via a network, and outputs the rotation speed command value to the inverter control circuit 22 according to the control signal from the control circuit 8. It is composed of a communication circuit 23 for outputting.

The communication circuit 23 is a signal conversion circuit for exchanging signals between the inverter control circuit 22 and the control circuit 8. The communication circuit 23 outputs the duty ratio of the PWM signal output from the inverter control circuit 22 to the control circuit 8. ing.

The components of the converter and the inverter shown in FIGS. 2 and 3 can be integrated into a module to reduce the size and cost.

Further, the converter control circuit 13 shown in FIG.
If a microcomputer having a network communication function is used for the inverter control circuit 22 shown in FIG. 3 and FIG. 3, the functions of the communication circuits 14 and 23 can be realized by the communication function of the microcomputer.

The control circuit 8 outputs the respective rotation speed command values to the plurality of inverters 2, 4 and 6 via the network (internal network) in accordance with the command signal input from the external network. In addition, each inverter 2,
The duty ratios of 4 and 6 are taken in through a network, a DC voltage value required for motor speed control is calculated based on these values, and the voltage command value is output to the converter 1 through the network.

FIG. 5 shows a DC voltage command changing method performed in the control circuit 8.

In step (S1), the conduction ratios of the inverters 2, 4, 6 are read via the network.
Next, in (S2), the maximum value is selected from the read flow rates.

In (S3), the maximum value of the selected conduction ratio is compared with the preset comparison value D1, and if the maximum conduction ratio is larger, the process proceeds to (S4) and the DC voltage command value is set. Is increased by a preset amount. In other cases, the process proceeds to (S5) to compare the maximum conduction ratio with the comparison value D2 again. If the comparison value D2 is large, the process proceeds to (S6) to set the DC voltage command value to a preset value. Decrease with.

The DC voltage command value obtained here is output to the converter 1 via the network.

In the above method, the maximum flow rate value and the comparison values D1 and D
It was only comparing 2 but each inverter 2, 4, 6
It is also possible to select the maximum conduction ratio value and the minimum conduction ratio value of and to obtain the DC voltage command value based on each value. FIG. 6 shows the algorithm.

The difference from FIG. 5 lies in the step (S2
′) And (S5 ′) only. Explaining only this part, in (S2 '), the maximum value and the minimum value are selected from the read conduction ratio.

Next, in (S3), the maximum value of the flow rate is compared with the comparison value D1, and if the maximum value is larger, (S3)
Proceed to 4) and increase the DC voltage command value.

In other cases, the process proceeds to (S5 ') to compare the minimum value of the flow rate with the comparison value D3. If the minimum value is smaller, the process proceeds to (S6) to decrease the DC voltage command value.

By using this algorithm, the conduction ratio of each of the inverters 2, 4 and 6 falls within the range between D1 and D3, and efficient motor control can be performed as a whole.

As described above, according to the present embodiment, a plurality of inverters and one converter are used for PWM for a plurality of motors.
In addition to control, speed control by PAM control is possible,
A fixed loss can be reduced and a highly efficient motor control device can be realized as compared with a system in which a converter is prepared for each inverter.

Therefore, for example, a great effect can be expected in a system having a large number of motors with a small output per unit, a fan motor control device in a building or the like.

In the above-mentioned embodiment, the duty factor is given as an example of the inverter status signal. However, the duty factor, input current, output current, output power, motor speed, motor load, consumption At least one of the power may be used.

Further, the control circuit 8 includes the inverters 2,
The input currents flowing into 4, 6 are detected, and the load of each motor is estimated (calculated) from the input current value, the DC voltage value of the converter 1 and the motor speed, and the optimum DC voltage value of the converter 1 is calculated. You may.

FIG. 7 shows the relationship between the converter DC voltage and the inverter duty ratio with respect to the motor speed when the motor control of the above embodiment is executed. This figure shows the condition under constant load torque.

This figure is a diagram when the algorithm shown in FIG. 5 is used. As shown in the figure, as the motor speed increases, the inverter 2 with the largest load is selected from the inverters 2, 4 and 6, and the inverter has a duty ratio of D.
When the rotation range is 1 or more, the PWM control shifts to the PAM control, and the DC voltage of the converter 1 is controlled stepwise.
Here, if the increase / decrease width of the DC voltage is made fine, the DC voltage apparently changes from a step shape to a linear shape, and the conduction ratio also changes to a linear shape.

FIG. 8 shows an overall configuration diagram of a second embodiment of a motor control device which performs the same operation as described above. The difference between this configuration diagram and the first embodiment is that the control circuit 8 is not provided outside the converter and the inverter. In the case of the present embodiment, it is a configuration diagram when the function (circuit) performed by the control circuit 8 is incorporated in a converter 100 (corresponding to the converter 1 in FIG. 1).

In this case, the data communicated through the network is only the duty ratio value of each inverter 2, 4, 6. Data (DC current value) in the converter 100 is processed in the converter.

Next, another embodiment of the present invention will be described with reference to FIG.
From now on, description will be made with reference to FIG.

FIG. 9 is an overall configuration diagram of a motor control device according to the third embodiment. This embodiment has almost the same configuration as that of the embodiment of FIG. 8 (that is, a circuit for controlling the DC voltage of the converter based on the status signals of the inverters 2, 4 and 6 is incorporated in the module of the converter 30). ,
The difference is that the converter 30 and each inverter 2, 4,
6 is connected not by network but by a signal line shown by a broken line, and that current detectors 41, 42, 43 for detecting the current flowing into each inverter 2, 4, 6 are provided on the power line of the inverter. is there.

Converter 30 and each inverter 2, 4, 6
A speed command value from the host is input to the signal line. The speed command value is given individually for each inverter, and different values can be given. In addition, the converter 30
The current value flowing into each inverter 2, 4, 6 is detected via the current detectors 41, 42, 43.

FIG. 10 shows an internal configuration diagram of the converter 30. The difference from FIG. 2 is that there is no communication circuit 14 and a DC voltage command circuit 15 is added instead.

The DC voltage command circuit 15 inputs the DC voltage value detected inside the converter 30, the speed command value from the host and the input current values of the respective inverters 2, 4 and 6, and based on this, Then, the converter control circuit 13
Determines (calculates) a DC voltage command value to be applied to the.

FIG. 11 shows a DC voltage command value changing method performed by the DC voltage command circuit 15. In (S1), the DC voltage value and the rotation speed command value and input current value of each inverter 2, 4, 6 are read, and in (S2) each inverter 2,
The outputs of 4 and 6 are calculated from the input current value and the DC voltage value.

Here, the output is obtained by multiplying the input current value and the DC voltage value. Originally, it was necessary to multiply by the coefficient in consideration of the efficiency of the inverter, but it was omitted here.

Next, in (S3), a DC voltage value required by each inverter 2, 4, 6 is obtained from the calculated outputs and the rotation speed command value, and the value is output as a DC voltage command value.

Here, the required DC voltage value is obtained by making a table from the values obtained in advance by measurement or the like and searching the table.

Here, the value of the DC voltage required for the motor speed control is obtained from the rotation speed command value and the actual output.
The current load torque may be estimated from the actual rotation speed and the actual output value, and the DC voltage value necessary for controlling to the rotation speed command value may be calculated.

The DC voltage value of the converter 30 and the respective inverters 2 with respect to the motor speed when the above embodiment is used.
The operation of the conduction ratios of 4 and 6 is shown in FIG. Similar to FIG. 7, this figure shows a state under the condition that the load torque is constant.

Although this drawing shows the case where the rotation speed command is also gradually changing, smooth control can be performed by shortening the control cycle (calculation cycle).

Next, a fourth embodiment will be described with reference to FIG. FIG. 13 shows the overall configuration of the fourth embodiment, in which the converter 40 is provided with the DC voltage command circuit 13 as in the third embodiment, and the same network as in the first embodiment is used. Is the case of using. The load of the motors 3, 5 and 7 is as follows:
A compressor for (air conditioner) and an indoor / outdoor fan. Basically nothing changes.

In the case of this circuit, the control circuit 80 is the remote controller 9
0 and the external network. A home network or the like can be considered as the external network.

If the home network is connected to a host device that monitors the power consumption in the home and the power consumption in the home is likely to exceed the allowable value, the output of the air conditioner is automatically output. It is possible to build a system that suppresses

14 and 15 show internal configuration diagrams (circuit diagrams) of the converter 40 and the inverters 50, 60 and 70 used in the embodiment of FIG. This figure is shown in FIGS.
Are combined, and each circuit has a built-in detection circuit for detecting a used current.
Naturally, the detected current value is passed through the network via the communication circuit.

A converter and an inverter system can be easily constructed by modularizing the converter and the inverter and connecting them by a network, and the converter determines the DC voltage value from the state of the inverter and operates. Is possible.

FIG. 16 to FIG. 18 relate to the fifth embodiment of the present invention and exemplify a home refrigerator, an air conditioner, and a microwave oven as the power control target of the power conversion device. A method of suppressing the output of the air conditioner when the allowable value is likely to be exceeded will be described.

FIG. 16 shows home appliances 201, 202, 2
03 and the host controller 200 that grasps the power consumption of each electric appliance 201, 202, 203 and controls the power consumption are connected by a network.

Each of the electric appliances 201, 202 and 203 outputs the amount of electric power used to the host controller 200 through the network. Here, the same effect can be obtained by connecting a power meter to the input side of each electric appliance and transmitting the power usage amount from the power meter to the host controller 200.

The host controller 200 is connected to a telephone line so that each electric appliance can be controlled from the outside. In this case, it is necessary to have a structure in which each electric appliance can be turned on and off by the signal of the network.

As shown in FIG. 17, the higher-level control device 200, in (S1), each electric appliance 201, 202, 2
The power consumption from 03 is read, and the total power in the home and which device is currently using the most power are calculated in (S2).

In (S3), the allowable power value which is the maximum amount of power that can be used by the home is compared with the current total power, and when the total power is about to exceed the allowable power, in other words, the total power is allowed. When the power amount is approached, the process proceeds to (S4), and the power usage restraint command signal and the set power amount of the device are output.

Here, the power consumption suppression command signal and the set power consumption are output to all the electrified appliances 201, 202, 203, only to the appliances using maximum power, or to the appliances with low priority. A method can be considered. Here, it is assumed that the air is output to the air conditioner having a low priority.

When the power use amount suppression command signal and the set power amount are output, the air conditioner 202 receives the signal and the control circuit 80 in the air conditioner performs the operation shown in FIG.

The power control circuit in the control circuit 80 is shown in FIG.
In step (S1) of each of the inverters 50, 6
The outputs from 0, 70 and the converter 40 are read, the electric power used in the entire air conditioner is calculated, and the result is output to the network in (S2). The output power consumption is read by the host controller 200.

Next, in (S3), the host controller 20
From 0, check whether the power consumption suppression command signal and the set power consumption are output to the air conditioner. If the power consumption suppression command signal and the set power consumption are output, go to (S5),
If not output, the process proceeds to (S4).

At (S4), the rotation speed is controlled according to a command from the remote controller which is a normal air conditioner control. In the case of (S5), power suppression control is performed.

The power suppression control is a method of controlling the power consumption of the air conditioner to the set power amount output from the host controller 200. Specifically, the rotation speed command value is lowered to set the power consumption to the set power amount. It is a control thing.

If the rotation speed command value changes, converter 40 and inverters 50, 60, 70 operate accordingly.

As described above, it is possible to bring out the maximum capacity within the range of the permissible electric power in the home and to highly efficiently control the operation of the electric appliances.

Although the above is a system for home use, an embodiment applied to an air conditioning fan control system for a clean room, a building, etc. is shown in FIG.

FIG. 19 shows a configuration in which three fan control devices 301, 302 and 303 equivalent to the contents described in the first embodiment are used.
2, 303 are connected to each phase of the three-phase power supply. By connecting the power supply lines in this way, the three-phase balance is secured.

The host controller 300 is connected to each unit via a network, and also monitors the current and voltage of the three-phase power supply.

As shown in FIG. 19, each fan control unit is connected by a network, and by grasping the power consumption and output torque of each fan, power control of each fan, failure diagnosis, filter clogging, etc. can be performed. Each fan control circuit can detect and can perform efficient motor control.

[0088]

According to the present invention, speed control by PAM control in addition to PWM control for a plurality of motors is possible with a plurality of inverters and one converter, and a converter is provided for each inverter. In addition, the fixed loss can be reduced and a highly efficient motor control device can be realized.

Therefore, for example, a great effect can be expected in a system having a small output per unit and having a large number of motors, a fan motor control device in a building or the like.

Further, by providing communication means such as a network in the converter or the inverter, calculating the amount of power used, the input current, the output torque, etc. and controlling them by the host controller, power control, failure diagnosis, etc. can be performed. .

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a motor control device according to a first embodiment of the present invention.

FIG. 2 is an internal configuration diagram of a converter used in the first embodiment.

FIG. 3 is an internal configuration diagram of an inverter used in the first embodiment.

FIG. 4 is an overall configuration diagram of a motor control device according to a conventional technique.

FIG. 5 is a flowchart showing a DC voltage command changing method according to the first embodiment.

FIG. 6 is a flowchart showing another example of the DC voltage command changing method according to the first embodiment.

FIG. 7 is an operation explanatory diagram according to the first embodiment.

FIG. 8 is an overall configuration diagram of a motor control device according to a second embodiment of the present invention.

FIG. 9 is an overall configuration diagram of a motor control device according to a third embodiment of the present invention.

FIG. 10 is a configuration diagram of a converter used in the third embodiment.

FIG. 11 is a flowchart showing a DC voltage command changing method according to the third embodiment.

FIG. 12 is an operation explanatory diagram according to the third embodiment.

FIG. 13 is an overall configuration diagram of an air conditioner control device according to a fourth embodiment of the present invention.

FIG. 14 is a configuration diagram of a converter used in the fourth embodiment.

FIG. 15 is a configuration diagram of an inverter used in the fourth embodiment.

FIG. 16 is a configuration diagram of a motor control device for home electric appliances according to a fifth embodiment of the present invention.

FIG. 17 is a flowchart showing a home power control method according to the fifth embodiment.

FIG. 18 is a method for controlling electric power in an air conditioner according to another embodiment of the present invention.

FIG. 19 is an overall configuration diagram of a motor control device according to a sixth embodiment of the present invention.

[Explanation of symbols]

1, 30, 40, 100 ... Converter, 2, 4, 6, 5
0, 60, 70 ... Inverter, 8, 80 ... Control circuit, 2
00, 300 ... Higher-order control device, 3, 5, 7 ... Motor, 1
3 ... Converter control circuit, 14, 23 ... Communication circuit, 15
... DC voltage command circuit, 21 ... Inverter main circuit, 22 ...
Inverter control circuit, 301, 302, 303 ... Motor control device unit, 90 ... Remote control.

Continuation of the front page (56) Reference JP-A-7-222456 (JP, A) JP-A-11-313441 (JP, A) JP-A-63-283493 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) H02P 7/67 H02M 7/48

Claims (9)

(57) [Claims] 1. An inverter capable of controlling the rotation speed of a motor is connected to one converter capable of converting an AC power supply into a DC power and controlling a DC voltage, and the speed of each motor is controlled by each of the inverters. to capture via the communication means a state signal of the inverter, by controlling the DC voltage of the converter on the basis of these status signals, comprising means for controlling the rotational speed of the plurality of motors, the converter Control of DC voltage is controlled by multiple inverters.
Inverter with the highest load among the signals captured from
The status signal of the data is selected and based on this selected status signal.
A control device for a plurality of motors, characterized in that it is configured to be carried out . 2. An AC power source is converted into a DC voltage and a DC voltage is converted.
The motor speed is controlled by one converter that can be controlled.
A plurality of inverters that can control the
In addition to controlling the speed of each motor by a controller, the status signals of the converter and the inverter are input to a higher-order control device via communication means, and the higher-order control device performs the above-mentioned operation based on the status signals of a plurality of inverters. Determining the DC voltage value of the converter, outputting the command value , and
The determination of the DC voltage value of the converter depends on a plurality of inverters.
Of the signals loaded from the
The status signal of the data is selected and based on this selected status signal.
A control device for a plurality of motors, which is configured to be executed first . 3. An AC power source is converted into a DC voltage and a DC voltage is converted.
The motor speed is controlled by one converter that can be controlled.
A plurality of inverters that can control the
In addition to controlling the speed of each motor by the data controller, the converter module incorporates the status signals of the plurality of inverters through the communication means and the communication means, and the DC voltage of the converter is calculated based on these status signals. A control circuit that determines and outputs a control command is incorporated ,
Moreover, the DC voltage value of the converter is determined by a plurality of
The signal with the largest load among the signals acquired from the burner
The status signal of the inverter is selected, and the selected status signal is selected.
A controller for a plurality of motors, which is configured to be executed based on the above . Wherein said converter and said control device by multiple motors according to any one of claims 1 to 3, to use the network to communicate with each inverter. 5. An AC power source is converted into a DC voltage and a DC voltage is converted.
The motor speed is controlled by one converter that can be controlled.
A plurality of inverters that can control the
In addition to controlling the speed of each motor by the motor, the status signals of these inverters are acquired via communication means.
The DC of the converter based on these status signals.
By controlling the voltage, the rotation speed of the multiple motors can be controlled.
A control means for controlling said control means, as the inverter state signal, the converter requiring incorporate a DC voltage value and the motor rotation speed of the the input electric current values flowing to the each inverter converter this having an arithmetic means for calculating a DC voltage value
And a control device for a plurality of motors. 6. An AC power source is converted to a DC voltage and a DC voltage is converted.
The motor speed is controlled by one converter that can be controlled.
A plurality of inverters that can control the
In addition to controlling the speed of each motor by a data controller , the status signals of the converter and the inverter are transmitted by communication means.
Is input to the higher-level control device via the
Based on the status signals of a plurality of inverters.
Determines the DC voltage value of the data, outputs the command value, and
Controller of the higher-level, direct current of the converter that requires capturing a DC voltage value of the converter and the input electric current values flowing before <br/> SL each inverter as an inverter state signal and the motor speed A control device for a plurality of motors, comprising a calculation means for calculating a voltage value. 7. An AC power source is converted into a DC voltage and a DC voltage is converted.
The motor speed is controlled by one converter that can be controlled.
A plurality of inverters that can control the
In addition to controlling the speed of each motor by the motor , communication means and
Capture status signals of multiple inverters via communication means
The DC voltage of the converter based on those status signals.
A control circuit that determines and outputs a control command is incorporated,
And the control circuit, calculation for calculating a DC voltage value of the converter requiring incorporate a DC voltage value of the converter and the input electric current values flowing to the each inverter as an inverter state signal and the motor speed Equipped with means
A control device for a plurality of motors characterized by the above . 8. An inverter circuit having a motor rotation speed control function is connected to a communication circuit having a function of inputting a rotation speed command signal from the outside and transmitting internal information of the inverter itself to the outside. An inverter module in which a communication circuit is installed on the same substrate and integrated. 9. An inverter module for controlling the rotation speed of a motor using a microcomputer, wherein the microcomputer has a communication function using a network, and controls the rotation speed of the motor according to a command signal from the network. An inverter module characterized by being capable of outputting an inverter control status signal to the outside through a network.