WO2019146022A1

WO2019146022A1 - Motor control device

Info

Publication number: WO2019146022A1
Application number: PCT/JP2018/002165
Authority: WO
Inventors: 昂司岡川; 彰畑井
Original assignee: 三菱電機株式会社
Priority date: 2018-01-24
Filing date: 2018-01-24
Publication date: 2019-08-01
Also published as: JP6567223B1; JPWO2019146022A1

Abstract

This motor control device (2) is provided with: a convertor circuit (5) which converts AC power to DC power and comprises upper and lower arms, a first switching element being provided on either the upper arm or the lower arm; a surge current suppression circuit (4) which is connected in parallel to the first switching element and has a second switching element and a resistor connected in series to the second switching element; a capacitor (8) connected in parallel to the converter circuit (5) on the output side of the converter circuit (5); and a control circuit (7) for controlling the first switching element and the second switching element.

Description

Motor controller

The present invention relates to a motor control device having a function of suppressing inrush current.

A mechanical device used for smoke exhaust in a building or a factory is required to operate the motor to smoke in an emergency. In general, a converter and a power converter including a capacitor on the output side of the converter are used in a motor controller incorporated in such a mechanical device. Here, in order to prevent the inrush current from flowing when the power conversion device is activated, that is, when the AC power is turned on, an inrush current suppression circuit is often provided.

In the power conversion device described in Patent Document 1, an inrush current suppression circuit configured of a diode and a resistor connected in series with each other is connected between the AC power supply and the converter circuit of the power conversion device.

JP 2001-238459 A

However, in the motor control device described in Patent Document 1 having the inrush current suppression circuit, there is a problem that standby power is generated because energization is continued in the inrush current suppression circuit in a standby state other than an emergency. there were.

The present invention has been made in view of the above, and an object thereof is to obtain a motor control device capable of suppressing generation of standby power in a rush current suppression circuit.

In order to solve the problems described above and to achieve the object, the present invention is composed of upper and lower arms having a first switching element in either the upper arm or the lower arm, and converts AC power into DC power. And a resistor circuit connected in series to the second switching element and the second switching element, and an inrush current suppression circuit connected in parallel to the first switching element. Furthermore, the present invention comprises a capacitor connected in parallel with the converter circuit on the output side of the converter circuit, and a control circuit for controlling the first switching element and the second switching element.

The motor control device according to the present invention has the effect of being able to suppress the generation of standby power in the inrush current suppression circuit.

The figure which shows the structure of the mechanical apparatus concerning Embodiment 1 of this invention. The figure which shows the structure of the mechanical apparatus concerning Embodiment 2 of this invention. The figure which shows the structure of the mechanical apparatus concerning Embodiment 3 of this invention. The figure which shows the structure of the mechanical apparatus concerning Embodiment 4 of this invention.

Hereinafter, a motor control device according to an embodiment of the present invention will be described in detail based on the drawings. The present invention is not limited by the embodiment.

Embodiment 1
FIG. 1 is a diagram showing the configuration of a mechanical device 1 according to a first embodiment of the present invention. A specific example of the mechanical device 1 is a mechanical device for smoke exhaust. The mechanical device 1 includes a motor control device 2 that converts power supplied from an AC power supply, and a motor 3 driven by the motor control device 2. That is, a three-phase or single-phase AC power supply is connected to the input end of the motor control device 2, and the motor 3 is connected to the output end of the motor control device 2.

The motor control device 2 includes an inrush current suppression circuit 4, a converter circuit 5 for converting AC power to DC power, an inverter circuit 6 for converting DC power to AC power to drive the motor 3, and a control circuit 7. It has the capacitor | condenser 8 for smoothing which is an electrolytic capacitor, and the voltage measurement part 30 which measures the voltage of the capacitor | condenser 8. FIG. Although converter circuit 5 is described below as converting three-phase AC power to DC power, converter circuit 5 may convert single-phase AC power to DC power.

The inrush current suppression circuit 4 is a circuit for suppressing the inrush current at the time of charging which flows into the capacitor 8 immediately after the AC power supply is turned on. The control circuit 7 controls the inrush current suppression circuit 4, the converter circuit 5 and the inverter circuit 6. Further, as described later, when the control circuit 7 receives an emergency signal indicating that the exhaust gas start is required from the host controller 17 provided outside the mechanical device 1, the inrush current suppression circuit 4 and the converter circuit 5 are Transmit control signals to Here, the control circuit 7 uses the voltage value measured by the voltage measurement unit 30 in order to determine the completion of charging of the capacitor 8.

Next, the circuit connection of the motor control device 2 will be described in detail. The

input terminals

101, 102, and 103 of the converter circuit 5 are provided corresponding to each of the R phase, S phase, and T phase of the AC power supply. Then, signals of R-phase, S-phase, and T-phase of the AC power supply are input to the

input terminals

101, 102, and 103, respectively.

Here, converter circuit 5 has an upper arm constituted by switching

elements

11, 12, 13 which are first switching elements, and a lower arm constituted by

diode elements

14, 15, 16. In FIG. 1, the R-phase upper and lower arms are composed of the R-phase upper arm which is the switching element 11 and the R-phase lower arm which is the diode element 14, and the R-phase upper arm and the R-phase lower arm are connected in series with each other. The input terminal 101 is connected to the electrical connection point between the R-phase upper arm and the R-phase lower arm. The S-phase upper and lower arms and the T-phase upper and lower arms have the same configuration, and the R-phase upper and lower arms, the S-phase upper and lower arms, and the T-phase upper and lower arms are connected in parallel with each other to form a three-phase upper and lower arm.

The inrush current suppression circuit 4 includes a switching element 9 which is a second switching element, and a resistor 10 which is a resistor connected in series to the switching element 9. Further, inrush current suppression circuit 4 is connected between a terminal connected to an AC power supply and positive electrode side output terminal 201 of converter circuit 5. That is, the inrush current suppression circuit 4 is connected in parallel with the switching element of the upper arm of the converter circuit 5. Note that one terminal of the inrush current suppression circuit 4 may be physically connected not to the positive electrode side output terminal 201 itself but to a connection point at which the positive electrode side output terminal 201 is at the same electrical potential. Although the inrush current suppression circuit 4 is connected in parallel with the switching element 11 of the R-phase upper arm in FIG. 1, it may be connected in parallel with the switching element 12 of the S-phase upper arm. The elements 13 may be connected in parallel. That is, the inrush current suppression circuit 4 may be connected in parallel to the switching element of the upper arm constituting the converter circuit 5 without being limited to the R phase.

Input terminals

61 and 62 of the inverter circuit 6 and both terminals of the smoothing capacitor 8 are connected to the positive output terminal 201 and the negative output terminal 202 of the converter circuit 5, respectively. That is, the capacitor 8 is connected in parallel with the converter circuit 5 on the output side of the converter circuit 5. The motor 3 is connected to the output terminal of the inverter circuit 6.

In the motor control device 2, the inrush current flowing to the capacitor 8 immediately after the AC power is turned on is suppressed by the inrush current suppression circuit 4. Then, converter circuit 5 converts the first AC power input from the AC power supply to

input terminals

101, 102, 103 into DC power, and the DC power is output from positive electrode side output terminal 201 and negative electrode side output terminal 202. Output. The inverter circuit 6 converts the DC power output from the converter circuit 5 to the positive electrode side output terminal 201 and the negative electrode side output terminal 202 into second AC power, and supplies the second AC power to the motor 3. The control circuit 7 can variably control the frequency of the second AC power generated by the inverter circuit 6.

The control circuit 7 controls the energization of the inrush current suppression circuit 4 by transmitting a control signal to the gate electrode of the switching element 9 of the inrush current suppression circuit 4. That is, when the control signal for turning on the switching element 9 is transmitted, the inrush current suppression circuit 4 is energized, and if the control signal for turning off the switching element 9 is transmitted, the inrush current suppression circuit 4 is electrically disconnected. Become. For example, as a control for the on operation, a positive voltage may be applied to the gate electrode of the switching element 9 as a control signal, and for a control for the off operation, a control signal applied to the gate electrode of the switching element 9 It is sufficient to change the positive voltage at the time of on operation to 0V.

At the start of the smoke exhaust operation, switching element 9 of inrush current suppression circuit 4 is rendered conductive in response to a control signal corresponding to the on operation from control circuit 7. When the switching element 9 becomes conductive, a conduction path is formed between the AC power supply and the capacitor 8 via the switching element 9 and the resistor 10, charging of the capacitor 8 becomes possible, and charging is started.

FIG. 1 shows the case where a thyristor element is used as the switching element 9. The thyristor element is cut off after a control signal corresponding to the OFF operation is transmitted from the control circuit 7 to the gate electrode of the thyristor element, after a conduction maintaining time determined from the electrical characteristics of the thyristor element.

The control circuit 7 controls the

switching elements

11, 12, 13 which are the first switching elements constituting the converter circuit 5 and the switching element 9 which is the second switching element which constitutes the inrush current suppression circuit 4. Then, control circuit 7 interrupts electrical conduction between inrush current suppression circuit 4 and converter circuit 5 in normal operation. Specifically, since

switching elements

9, 11, 12, 13 are elements capable of interrupting electrical conduction by the control signal, control circuit 7 normally switches the control signal for the OFF operation to switching

element

9 , 11, 12, and 13 are applied to the gate electrodes. Then, when receiving an emergency signal indicating that exhaust gas start is necessary from the host controller 17 in an emergency, the control circuit 7 outputs a control signal for energization, that is, a control signal for on operation to the

switching elements

9, 11, 12. , 13 are applied to the gate electrodes. Since the control circuit 7 needs to be always operated, although not shown, a dedicated power supply of the control circuit 7 is provided in the motor control device 2.

Hereinafter, the operation of the motor control device 2 used for the exhaust gas mechanical device 1 will be described separately for normal and emergency.

In a normal state in which mechanical device 1 does not perform the smoke exhaust operation, control circuit 7 outputs a control signal for the off operation to inrush current suppression circuit 4 and converter circuit 5, and switching element 9 and switching

elements

11 and 12. , 13 in the shutoff state. As a result, no current flow path is formed in any of inrush current suppression circuit 4 and converter circuit 5, and current does not flow from capacitor AC and inverter circuit 6 from the AC power supply.

In an emergency where the mechanical device 1 carries out a smoke exhausting operation, the control circuit 7 outputs a control signal for the on operation to the inrush current suppression circuit 4 to make the switching element 9 conductive, thereby switching the switching element 9. And the current to the capacitor 8 through the resistor 10. Control circuit 7 determines that charging of capacitor 8 is completed based on the measurement result of voltage measurement unit 30, and then outputs a control signal for the on operation to converter circuit 5 to switch switching

elements

11, 12, and 13 Is turned on. Thus, converter circuit 5 can convert the input AC voltage into a DC voltage and output it. Thus, after the charging of the capacitor 8 is completed, the capacitor 8 and the inverter circuit 6 are energized from the AC power supply via the converter circuit 5.

When control signals for on operation are output to converter circuit 5 and switching

elements

11, 12 and 13 are brought into conduction, capacitor 8 and inverter circuit 6 are switched from the AC power supply even if rush current suppression circuit 4 is not conducted. Since the

switching elements

9, 12 and 13 become conductive, the inrush current suppression circuit 4 may be cut off by controlling the switching element 9 to the cut off state. In this case, it is possible to further reduce the standby power generated in inrush current suppression circuit 4 while converter circuit 5 is on.

The motor control device 2 according to the first embodiment includes the inrush current suppression function, and in parallel with the switching

elements

11, 12, and 13 constituting the upper and lower arms of the converter circuit 5, in order to reduce standby power. The inrush current suppression circuit 4 having the switching element 9 is provided. As a result, when the motor operation is started, the inrush current to the capacitor 8 can be suppressed by turning on the switching element 9 of the inrush current suppression circuit 4 while the switching element 11 of the converter circuit 5 is turned off. Since both the

switching elements

11, 12 and 13 of the converter circuit 5 and the switching element 9 of the inrush current suppression circuit 4 are turned off, the current to the converter circuit 5 and the inrush current suppression circuit 4 is cut off. Generation of standby power can be suppressed. That is, the inrush current suppression circuit 4 can be energized from the AC power supply only when the motor 3 needs to be operated, and the inrush current suppression circuit 4 can be electrically disconnected when it is not necessary.

Here, when the motor control device 2 according to the first embodiment is not used, consider, for example, a case where the motor control device is configured with a diode, which is not a switching element, connected in series with the resistance of the inrush current suppression circuit 4. . In this case, since the energization of the inrush current suppression circuit 4 is continued even when the motor is not in operation, the temperature of the parts rises due to the generation of the standby power, which leads to a decrease in the life of the parts. If the motor control device 2 according to the first embodiment is used, generation of the standby power of the inrush current suppression circuit 4 can be suppressed when the motor is not in operation, so that the component temperature rise can be suppressed. As a result, it is possible to prevent the deterioration of the parts due to the temperature rise of the parts and to realize the long life.

Also, in order to suppress power consumption due to standby power and component deterioration due to temperature rise, conventionally, in order to energize the motor control device from the power source only when necessary, a magnetic contactor, ie, a contactor, and a higher rank for contactor control There was a case to use a controller. In this case, man-hours for work of wiring connection to the contactor are required. Moreover, although the installation space for a contactor is also needed, there existed a problem that an installation space increases because a contactor is large. However, according to the motor control device 2 according to the first embodiment, a mechanical device for exhausting smoke that can shut off the current at normal times without using a contactor can be configured, so that the number of steps can be reduced, the size can be reduced, and the size can be reduced. Cost can be realized.

Second Embodiment
FIG. 2 is a diagram showing the configuration of a mechanical device 1A according to a second embodiment of the present invention. A specific example of the mechanical device 1A is a mechanical device for smoke exhaust. The mechanical device 1A according to the second embodiment differs from the mechanical device 1 according to the first embodiment in the configuration of the motor control device. The configuration of inrush current suppression circuit 4 differs between motor control device 2A according to the second embodiment and motor control device 2 according to the first embodiment. In the inrush current suppression circuit 4 of the motor control device 2A according to the second embodiment, the switching element 18 incorporates a resistor. That is, the resistor 10 of the inrush current suppression circuit 4 of the first embodiment corresponds to the on resistance of the switching element 18 in the second embodiment. The other configuration is the same as that of the first embodiment, and the same components as those in the first embodiment are denoted by the same reference numerals and redundant description will be omitted.

The switching element 18 which is the second switching element according to the second embodiment can shut off the current by the gate signal indicating the gate voltage, and adjusts the on-resistance by changing the value of the gate voltage. Use an element that can FIG. 2 shows an example in which an IGBT (Insulated Gate Bipolar Transistor) element is used as the switching element 18. That is, inrush current suppression circuit 4 according to the second embodiment is formed of an IGBT as switching element 18 and the on resistance of this IGBT.

Hereinafter, the operation of the motor control device 2A used in the smoke exhaust machine device 1A will be described separately for normal and emergency.

In a normal state in which mechanical device 1A does not perform the smoke exhausting operation, control circuit 7 outputs a control signal for off operation to inrush current suppression circuit 4 and converter circuit 5, and switching element 18 and switching

elements

11, 12 , 13 in the shutoff state. As a result, no current flow path is formed in any of inrush current suppression circuit 4 and converter circuit 5, and current does not flow from capacitor AC and inverter circuit 6 from the AC power supply.

In an emergency where the mechanical device 1A carries out a smoke exhausting operation, the control circuit 7 outputs a control signal for the on operation to the inrush current suppression circuit 4 to make the switching element 18 conductive. Conduction of switching element 18 forms a conduction path between AC power supply and capacitor 8 via switching element 18, and capacitor 8 can be charged by the current suppressed by the on resistance of switching element 18. It becomes. When the IGBT element is used as the switching element 18, the IGBT element has a characteristic that the on resistance is changed by the voltage inputted to the gate, so the gate voltage is adjusted to charge the capacitor 8 Inrush current can be suppressed. That is, the motor control device 2A according to the second embodiment obtains the same rush current suppression effect as the motor control device 2 having the configuration in which the switching element 9 and the resistor 10 described in the first embodiment are connected in series. Can.

Then, when an IGBT element is used as the switching element 18, the control circuit 7 outputs the gate voltage in a pulse shape, so that the current flowing through the IGBT element is also in a pulse shape, so the average conduction current can be reduced. . As a result, the temperature rise of the IGBT element can be suppressed. Further, the average conduction current of the IGBT element can be adjusted by adjusting the magnitude of the voltage amplitude of the gate voltage in accordance with the electrical characteristics of the IGBT element. As a result, the temperature of the IGBT element can be controlled. The switching element 18 may use an element other than the IGBT element as long as the on resistance can be adjusted by the gate signal.

In the present embodiment, although the case where rush current suppression circuit 4 is formed of only IGBT elements is disclosed, it goes without saying that inrush current suppression circuit 4 may be provided with a resistance connected in series to the IGBT elements. Yes.

Further, in order to prevent the occurrence of the overcurrent breakdown by causing the switching element 18 to reversely conduct, the switching element 18 can be provided with a reverse breakdown voltage characteristic or an element capable of preventing reverse conduction represented by a diode. It is necessary to connect in series with the switching element 18.

As described above, in the motor control device 2A according to the second embodiment, the gate of the switching element 18 constituting the inrush current suppression circuit 4 for suppressing the inrush current flowing to the capacitor 8 immediately after the AC power supply is turned on. By changing the voltage, the on resistance of the switching element 18 can be adjusted. Further, it is possible to suppress the temperature rise by outputting the gate voltage in a pulse shape, or to control the temperature of the element by adjusting the voltage amplitude of the gate voltage. Although the IGBT element is described as the switching element 18 in the second embodiment, the switching element 18 may be a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). That is, the switching element 18 may be any switching element whose resistance value of the on resistance is adjusted by the control signal from the control circuit 7.

Third Embodiment
FIG. 3 is a diagram showing the configuration of a mechanical device 1B according to a third embodiment of the present invention. A specific example of the mechanical device 1B is a mechanical device for smoke exhaust. The mechanical device 1B according to the third embodiment differs from the mechanical device 1 according to the first embodiment in the configuration of the motor control device. The motor control device 2B according to the third embodiment differs from the motor control device 2 according to the first embodiment in the configuration of the converter circuit, the configuration of the rush current suppression circuit, and the connection point. In motor control device 2B, converter circuit 5 is replaced with converter circuit 5B, inrush current suppression circuit 4 is replaced with inrush current suppression circuit 19, and the other configuration is similar to that of the first embodiment, The same reference numerals are given to constituent elements, and duplicate explanations are omitted.

The motor control device 2B includes an inrush current suppression circuit 19, a converter circuit 5B, an inverter circuit 6, a control circuit 7, a smoothing capacitor 8, and a voltage measurement unit 30.

Converter circuit 5B has an upper arm formed of

diode elements

22, 23, 24, and a lower arm formed of switching

elements

25, 26, 27 which are first switching elements. In FIG. 3, the R-phase upper and lower arms are composed of an R-phase upper arm which is a diode element 22 connected in series with each other and an R-phase lower arm which is a switching element 25. The input terminal 101 is connected to the target connection point. The S-phase upper and lower arms and the T-phase upper and lower arms have the same configuration, and the R-phase upper and lower arms, the S-phase upper and lower arms, and the T-phase upper and lower arms are connected in parallel with each other to form a three-phase upper and lower arm.

The control circuit 7 controls the inrush current suppression circuit 19, the converter circuit 5B and the inverter circuit 6. Further, as described later, when the control circuit 7 receives an emergency signal indicating that the exhaust gas start is required from the host controller 17 provided outside the mechanical device 1B, the rush current suppression circuit 19 and the converter circuit 5B Transmit control signals to Here, the control circuit 7 uses the voltage value measured by the voltage measurement unit 30 in order to determine the completion of charging of the capacitor 8.

Next, the circuit connection of the motor control device 2B will be described in detail.

Input terminals

101, 102, and 103 of converter circuit 5B are provided corresponding to the respective phases of the AC power supply. The inrush current suppression circuit 19 includes a switching element 20 which is a second switching element, and a resistor 21 which is a resistor connected in series to the switching element 20. In FIG. 3, the switching element 20 is shown by a thyristor element. In addition, inrush current suppression circuit 19 is connected between the terminal connected to the AC power supply and negative electrode side output terminal 202 of converter circuit 5B. That is, the inrush current suppression circuit 19 is connected in parallel with the switching element of the lower arm of the converter circuit 5B. Note that one terminal of the rush current suppression circuit 19 may be physically connected not to the negative electrode side output terminal 202 itself but to a connection point at which the negative electrode side output terminal 202 is electrically at the same potential. In FIG. 3, the inrush current suppression circuit 19 is connected in parallel with the switching element 27 of the T-phase lower arm, but may be connected in parallel with the switching element 25 of the R-phase lower arm. The elements 26 may be connected in parallel. That is, the inrush current suppression circuit 19 may be connected in parallel to the switching element of the lower arm constituting the converter circuit 5B as well as the T phase.

Input terminals

61 and 62 of the inverter circuit 6 and both terminals of the smoothing capacitor 8 are connected to the positive electrode side output terminal 201 and the negative electrode side output terminal 202 of the converter circuit 5B, respectively. The motor 3 is connected to the output terminal of the inverter circuit 6.

In the motor control device 2B, the inrush current flowing to the capacitor 8 immediately after the AC power is turned on is suppressed by the inrush current suppression circuit 19. At the start of the exhaust smoke operation, the switching element 20 of the inrush current suppression circuit 19 conducts in response to the control signal corresponding to the on operation from the control circuit 7. The conduction of the switching element 20 forms an electric conduction path between the AC power supply and the capacitor 8 via the switching element 20 and the resistor 21 so that the capacitor 8 can be charged and charging is started.

The control circuit 7 controls the switching

elements

25, 26 and 27 which are the first switching elements constituting the converter circuit 5 B and the switching element 20 which is the second switching element which constitutes the inrush current suppression circuit 19. Then, control circuit 7 interrupts electrical conduction between inrush current suppression circuit 19 and converter circuit 5B in normal operation. Specifically, since switching

elements

20, 25, 26, and 27 are elements that can cut off electrical conduction by a control signal, control circuit 7 normally switches the control signal for the off operation to switching element 20. , 25, 26, and 27 are applied to the gate electrodes. Then, when receiving an emergency signal indicating that exhaust gas start is required from the host controller 17 in an emergency, the control circuit 7 outputs a control signal for energizing, that is, a control signal for on operation, to the

switching elements

20, 25, 26. , 27 gate electrodes.

Hereinafter, the operation of the motor control device 2B used for the smoke exhaust machine device 1B will be described separately for normal and emergency.

In a normal state in which mechanical device 1B does not perform the smoke exhaust operation, control circuit 7 outputs a control signal for the off operation to inrush current suppression circuit 19 and converter circuit 5B, and switching element 20 and switching

elements

25, 26. , 27 in the shutoff state. As a result, no current flow path is formed in any of inrush current suppression circuit 19 and converter circuit 5B, and current does not flow from capacitor AC and inverter circuit 6 from the AC power supply.

In an emergency where the mechanical device 1B performs a smoke exhausting operation, the control circuit 7 outputs a control signal for the on operation to the inrush current suppression circuit 19 to make the switching element 20 conductive, thereby switching the switching element 20. And the current to the capacitor 8 through the resistor 21. Control circuit 7 determines that charging of capacitor 8 is completed based on the measurement result of voltage measurement unit 30, and then outputs a control signal for the on operation to converter circuit 5B to switch switching

elements

25, 26, 27. Is turned on. Thus, converter circuit 5B can convert the input AC voltage into a DC voltage and output it. Thus, after the charging of the capacitor 8 is completed, the capacitor 8 and the inverter circuit 6 are energized from the AC power supply through the converter circuit 5B.

As described above, the motor control device 2B according to the third embodiment is configured such that the inrush current suppression circuit is connected in parallel with the switching element of the lower arm, so that the motor control device 2B is implemented after having the inrush current suppression function. The small and simple configuration other than the mode 1 makes it possible to deenergize the AC power supply and to cut off electricity.

Fourth Embodiment
FIG. 4 is a diagram showing the configuration of a mechanical device 1C according to a fourth embodiment of the present invention. A specific example of the mechanical device 1C is a mechanical device for smoke exhaust. The mechanical device 1C according to the fourth embodiment differs from the mechanical device 1 according to the first embodiment in the configuration of the motor control device. The motor control device 2C according to the fourth embodiment differs from the motor control device 2 according to the first embodiment in the configuration of the converter circuit. In motor control device 2C, converter circuit 5 is replaced with converter circuit 5C, and the other configuration is the same as that of the first embodiment, and the same components are assigned the same reference numerals and duplicated. The description is omitted.

The motor control device 2C includes an inrush current suppression circuit 4, a converter circuit 5C, an inverter circuit 6, a control circuit 7, a smoothing capacitor 8, a voltage measuring unit 30, and a capacitance for noise suppression. And the capacitive element 28. The capacitive element 28 has a configuration in which a capacitive element between the input terminal 61 of the inverter circuit 6 and the ground and a capacitive element between the input terminal 62 of the inverter circuit 6 and the ground are connected in parallel. Therefore, the capacitive element 28 is connected to the capacitor 8.

Control circuit 7 controls inrush current suppression circuit 4, converter circuit 5 C and inverter circuit 6. Further, as described later, when the control circuit 7 receives an emergency signal indicating that the exhaust gas start is required from the host controller 17 provided outside the mechanical device 1C, the rush current suppression circuit 4 and the converter circuit 5C Transmit control signals to Here, the control circuit 7 uses the voltage value measured by the voltage measurement unit 30 in order to determine the completion of charging of the capacitor 8.

Next, the circuit connection of the motor control device 2C will be described in detail.

Input terminals

101, 102, and 103 of converter circuit 5C are provided corresponding to the respective phases of the AC power supply. Further, the rush current suppression circuit 4 is connected between the input terminal 101 to which the R-phase signal of the AC power supply is input and the positive electrode side output terminal 201 of the converter circuit 5C. The terminal connected to the AC power supply of the rush current suppression circuit 4 may be connected to the input terminal 102 and the input terminal 103 instead of or in addition to the input terminal 101. That is, the inrush current suppression circuit 4 is connected between the positive electrode side output terminal 201 and the input terminal corresponding to at least one phase of the AC power supply as well as the R phase. The

input terminals

61 and 62 of the inverter circuit 6 and both terminals of the smoothing capacitor 8 are connected to the positive electrode side output terminal 201 and the negative electrode side output terminal 202 of the converter circuit 5C, respectively. The motor 3 is connected to the output terminal of the inverter circuit 6. The inrush current suppression circuit 4 includes a switching element 9 and a resistor 10 connected in series.

Converter circuit 5C has an upper arm constituted by switching

elements

11, 12 and 13 which are first switching elements, and a lower arm constituted by switching elements 25 26 and 27 which are third switching elements. In FIG. 4, the R-phase upper and lower arms are composed of the R-phase upper arm which is the switching element 11 and the R-phase lower arm which is the switching element 25 connected in series with each other. The input terminal 101 is connected to the target connection point. The S-phase upper and lower arms and the T-phase upper and lower arms have the same configuration, and the R-phase upper and lower arms, the S-phase upper and lower arms, and the T-phase upper and lower arms are connected in parallel with each other to form a three-phase upper and lower arm.

In FIG. 4, the inrush current suppression circuit 4 is connected in parallel with the switching element 11 of the R-phase upper arm. Here, as described above, since the inrush current suppression circuit 4 may be connected between at least one of the

input terminals

101, 102, and 103 and the positive electrode side output terminal 201, the inrush current The suppression circuit 4 may be connected in parallel with the switching element of the upper arm of at least one of the R-phase upper arm, the S-phase upper arm and the T-phase upper arm.

The control circuit 7 is a second switching element constituting the inrush current suppression circuit 4 and the

switching elements

11, 12, 13, 25, 26, 27 which are the first and third switching elements constituting the converter circuit 5C. The switching element 9 is to be controlled. Then, control circuit 7 interrupts electrical conduction between inrush current suppression circuit 4 and converter circuit 5C in normal operation. Specifically, since switching

elements

9, 11, 12, 13, 25, 26, and 27 are elements that can cut off electrical conduction by a control signal, control circuit 7 normally operates for off operation. A control signal is applied to the gate electrodes of the

switching elements

9, 11, 12, 13, 25, 26 and 27. Then, upon receiving an emergency signal indicating that exhaust gas start is required from the host controller 17 in an emergency, the control circuit 7 generates a control signal for energizing, that is, a control signal for on operation, the switching element 9 and the switching element 11. , 12, 13, 25, 26, and 27 are applied to the gate electrodes.

When the capacitive element 28 is connected to the capacitor 8 as a noise countermeasure, a current path from the AC power source to the ground through the inrush current suppression circuit 4, the capacitor 8 and the capacitive element 28, and the upper arm of the converter circuit 5 C from the AC power source There is a current path to ground through capacitor 8 and capacitive element 28, and a current path from the AC power supply to the lower arm of converter circuit 5C, to ground through capacitor 8 and capacitive element 28.

In the normal state where the mechanical device 1C does not perform the exhaust operation, the charge of the capacitor 8 is not consumed, so the capacitor 8 may be charged by the above current path. The capacitor 8 being charged in an ordinary state in which the motor 3 is not operated and having an unintended voltage may cause a malfunction or destruction of the motor control device 2C. Therefore, the motor control device 2C needs to operate so that the capacitor 8 is not charged in normal operation.

Hereinafter, the operation of the motor control device 2C used for the smoke exhaust machine device 1C will be described separately for normal and emergency.

In a normal state in which mechanical device 1C does not carry out a smoke exhausting operation, control circuit 7 outputs a control signal for off operation to inrush current suppression circuit 4 and converter circuit 5C, switching element 9 and switching

elements

11 and 12 , 13, 25, 26, 27 in the shutoff state. As a result, no current flow path is formed in any of inrush current suppression circuit 4 and converter circuit 5C, and current does not flow from capacitor AC and inverter circuit 6 from the AC power supply.

In an emergency where the mechanical device 1C performs a smoke exhausting operation, the control circuit 7 outputs a control signal for the on operation to the inrush current suppression circuit 4 to make the switching element 9 conductive, thereby switching the switching element 9 And the current to the capacitor 8 through the resistor 10. Control circuit 7 determines that charging of capacitor 8 is completed based on the measurement result of voltage measurement unit 30, and then stops the control signal to inrush current suppression circuit 4 to put switching element 9 in the cutoff state. A control signal for the on operation is output to converter circuit 5C to make switching

elements

11, 12, 13, 25, 26, 27 conductive. Thus, converter circuit 5C can convert the input AC voltage into a DC voltage and output it. Thus, after the charging of the capacitor 8 is completed, the capacitor 8 and the inverter circuit 6 are energized from the AC power supply via the converter circuit 5C.

When an AC reactor is connected between the AC power supply and motor control device 2C, or when phase control or power factor control is applied to converter circuit 5C, capacitor 8 and AC power supply described above are used. The energization operation to the inverter circuit 6 can be implemented without any problem.

In the above, in the motor control device 2C, the inrush current suppression circuit 4 is connected between the input terminal corresponding to at least one phase of the AC power supply and the positive electrode side output terminal 201, but the rush current As in the motor control device 2B of the third embodiment, the rush current suppression circuit 19 is connected between the input terminal corresponding to at least one phase of the AC power supply and the negative output terminal 202 without connecting the suppression circuit 4 to this point. It does not matter if it is provided. In this case, switching

elements

25, 26 and 27 connected in parallel with rush current suppression circuit 19 are used as the first switching elements, and the remaining

switching elements

11, 12 and 13 of converter circuit 5C are used as the third switching elements. I assume. Furthermore, as described in the second embodiment, the inrush current suppression circuit 4 or the inrush current suppression circuit 19 may be configured using the switching element 18 whose ON resistance can be adjusted based on the gate signal.

As described above, according to the motor control device 2C according to the fourth embodiment, even when the capacitive element 28 for noise reduction is provided, the motor control device 2C is small and simple with the inrush current suppression function. Depending on the configuration, energization from the AC power supply and electrical disconnection can be achieved.

The configuration shown in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and one of the configurations is possible within the scope of the present invention. Parts can be omitted or changed.

1, 1A, 1B, 1C Machine device, 2, 2A, 2B, 2C motor control device, 3 motor, 4, 19 rush current suppression circuit, 5, 5B, 5C converter circuit, 6 inverter circuit, 7 control circuit, 8

capacitor

9, 11, 12, 13, 18, 20, 25, 26, 27 switching elements, 10, 21 resistors, 14, 15, 16, 22, 23, 24 diode elements, 17 upper controller, 28 capacitive elements, 30 Voltage measurement unit.

Claims

A converter circuit configured of an upper arm and a lower arm, the upper and lower arms having a first switching element, and converting AC power into DC power;
An inrush current suppression circuit having a second switching element and a resistor connected in series to the second switching element, and connected in parallel to the first switching element;
A capacitor connected in parallel with the converter circuit on the output side of the converter circuit;
A control circuit for controlling the first switching element and the second switching element;
Motor controller equipped with
The motor control device according to claim 1, wherein the resistance is an on-resistance built in the second switching element, and the control circuit controls a resistance value of the on-resistance.
A capacitive element connected between the capacitor and the ground;
The motor control device according to claim 1, wherein the upper and lower arms of the converter circuit have a third switching element connected in series to the first switching element.
The motor control device according to any one of claims 1 to 3, wherein the control circuit controls so that a pulse current flows in the second switching element.
The motor control device according to any one of claims 1 to 4, wherein the converter circuit converts three-phase AC power into DC power.