JP6336250B2 - Inverter device - Google Patents

Description

  Embodiments described herein relate generally to an inverter device having a braking function.

  In recent years, inverter devices have been used for lift and elevator applications. The inverter device is used by being connected to a commercial power source in normal times. On the other hand, in the event of an emergency such as a power outage, a battery (DC auxiliary power supply) with a voltage lower than the normal input voltage (voltage obtained by rectifying the AC voltage of the commercial power supply) is connected to the inverter device, and the inverter device is temporarily activated. Therefore, a function (rescue operation) for driving to the nearest floor is required. The number of batteries used in an emergency is better when the installation location, maintenance, cost, etc. are taken into consideration.

  However, for example, the torque of the induction motor has a characteristic that is approximately proportional to V (voltage) / F (frequency). Therefore, if the output voltage of the inverter device is low, sufficient torque output can be obtained unless the frequency is low. Absent. In order to rescue a person in the elevator early in an emergency, it is necessary to devise a technique for obtaining a sufficient torque output at a high frequency even when a battery having a voltage lower than the normal input voltage is used.

JP 2002-171783 A

  Therefore, an inverter device is provided that can output a high voltage to a load even when a DC auxiliary power supply having a voltage lower than the normal input voltage is used.

The inverter device of the embodiment includes an inverter circuit that outputs an AC voltage to a load, a positive DC power supply line that connects an output terminal of a DC main power supply and an input terminal of the inverter circuit, a negative DC power supply line, and the positive DC power supply. the anode of limited resistor arranged line inrush current limiting circuit comprising a parallel circuit of a short-circuit switch, with a cathode connected to the positive DC power supply line between the pre-Symbol inrush current limiting circuit and the inverter circuit There is connected in parallel with the first diode connected to the braking pin the braking terminal brake switch circuit consisting of a switching element connected between the negative-side DC power supply line, and with the brake switch circuit It has a capacitor .

Further, a second diode provided in the positive DC power supply line between the positive output terminal of the DC main power supply and the inrush current limiting circuit with the DC main power supply side as an anode, and a DC auxiliary power supply in series In a connected state, the positive output terminal of the DC main power supply and the positive electrode of the DC auxiliary power supply are connected between the positive output terminal and the negative output terminal of the DC main power supply , and the A third diode for preventing backflow connected in a direction to discharge from the DC auxiliary power supply, a reactor having one end connected to the positive output terminal of the DC main power supply, and one end connected to the cathode of the second diode A braking resistor, a changeover switch for selecting any one of the other end of the reactor and the other end of the braking resistor and connecting to the braking terminal, and a control circuit are provided.

  When the DC main power source can supply a DC voltage, the control circuit connects the other end of the braking resistor to the braking terminal by a changeover switch, and controls the braking of the load by turning on the switching element according to a predetermined braking condition. . On the other hand, when the DC main power supply cannot supply a DC voltage due to a power failure or the like, the other end of the reactor is connected to the braking terminal by a changeover switch, and the switching element is turned on and off to boost the voltage of the DC auxiliary power supply. To do.

The block diagram of the inverter apparatus which shows 1st Embodiment Sequence diagram at power failure FIG. 1 equivalent diagram showing the second embodiment FIG. 1 equivalent view showing the third embodiment FIG. 1 equivalent view showing the fourth embodiment FIG. 1 equivalent diagram showing the fifth embodiment FIG. 1 equivalent view showing the sixth embodiment FIG. 1 equivalent diagram showing a seventh embodiment

Each embodiment described below applies an inverter device to an elevator control device. In each embodiment, substantially the same parts are denoted by the same reference numerals and description thereof is omitted.
(First embodiment)
A first embodiment will be described with reference to FIGS. 1 and 2. Although not shown in the drawings, the elevator has a configuration in which a passenger car and a counterweight that can move up and down a hoistway provided in a building are connected by a main rope. The main rope is hung on a sheave of a hoisting machine provided at the upper part of the hoistway, and a car is connected to one end of the main rope, and a counterweight is connected to the other end. The elevator control device drives the motor 2 of the hoisting machine using the inverter device 1 described below, so that the hoisting machine winds up the main rope and raises / lowers the car along the hoistway.

  The inverter device 1 is supplied with AC power from a three-phase commercial power source 3 via a contactor 4 and drives an electric motor 2 (load) such as an induction motor or a synchronous motor constituting a hoisting machine. A battery 5 as a DC auxiliary power supply is prepared for the inverter device 1 in preparation for when the commercial power supply 3 fails. The inverter device 1 is mainly composed of an inverter unit 6 configured with versatility.

  The inverter unit 6 includes a converter 7, a capacitor 8, an inverter 9, an inrush current limiting circuit 10, a braking switch circuit 11, a control circuit 12, and drive circuits 13 and 14. Further, the inverter unit 6 includes an input terminal 16 to which input-side power lines 15u, 15v, and 15w are connected, an output terminal 17 to which the motor 2 is connected, and external terminals 18 to 18 for connecting an inductor, a braking resistor, and the like. 21 is provided.

  The inverter 9 is composed of a switching element such as an IGBT connected in a three-phase bridge. A diode is connected in antiparallel to each IGBT. The converter 7 functions as a DC main power supply, and is a rectifier circuit composed of a diode connected in a three-phase bridge. A smoothing capacitor 8 is connected between a positive DC power supply line 22 and a negative DC power supply line 23 that connect the output terminal of the converter 7 and the input terminal of the inverter 9. Hereinafter, the positive DC power supply line 22 and the negative DC power supply line 23 are referred to as a power supply line 22 and a power supply line 23, respectively.

  The power supply line 22 is provided with the external terminals 18 and 19 described above, and the external terminals 18 and 19 are open. The external terminal 18 is connected to the positive output terminal of the converter 7, and the external terminal 19 is connected to the positive input terminal of the inverter 9 via the inrush current limiting circuit 10. In a general usage mode different from the present embodiment and in a fourth embodiment described later, a reactor for suppressing harmonic currents flowing in the power supply lines 15u to 15w is connected between the external terminals 18 and 19.

  The inrush current limiting circuit 10 includes an inrush current limiting resistor 24 and a relay 25. The limiting resistor 24 and the relay contact 25b are connected in parallel. The relay contact 25b functions as a short-circuit switch, and when the relay coil 25a is energized, the relay contact 25b is closed and a path through the limiting resistor 24 is formed.

  The braking switch circuit 11 includes a first diode 26 and an IGBT 27 (switching element) connected in series with the external terminal 20 between the power supply lines 22 and 23 between the inrush current limiting circuit 10 and the inverter 9. Has been. The cathode of the diode 26 is connected to the power line 22. The external terminal 20 corresponds to a braking terminal.

  The control circuit 12 is mainly composed of a microcomputer, and executes an operation control program stored in a nonvolatile memory (not shown) to start, stop, accelerate, decelerate, brake, and increase the battery voltage. Perform processing such as control. The control circuit 12 outputs an energization signal to the relay 25 to energize the relay coil 25a. Further, the control circuit 12 outputs a PWM drive signal to the inverter 9 via the drive circuit 13 to output an AC voltage to the electric motor 2, and outputs an on drive signal to the IGBT 27 via the drive circuit 14. Turn on.

  In addition to the inverter unit 6 described above, the inverter device 1 of the present embodiment has the following configuration. A second diode 28 having the external terminal 18 side as an anode is connected between the external terminal 18 and the external terminal 19, that is, between the positive output terminal of the converter 7 and the inrush current limiting circuit 10. Yes. In the inverter unit 6, the external terminal 21 is connected to the power line 23. The battery 5, the switch 34, and the third diode 29 are connected in series between the external terminal 18 and the external terminal 21, that is, between the positive side output terminal and the negative side output terminal of the converter 7. The cathode of the diode 29 is connected to the external terminal 18.

  The switch 34 is turned off by a signal from the host control device 33 when the battery 5 is disconnected from the inverter device 1 including maintenance. The switch 34 is on during normal operation and rescue mode operation. In order to avoid unnecessary discharge of the battery 5, the contactor 4 and the switch 34 are turned on in the order when the power is turned on during normal times, and the switch 34 and the contactor 4 are turned off when the power is turned off.

  Furthermore, the inverter device 1 includes a reactor 30 used for boosting, a braking resistor 31 used for braking, and a changeover switch 32. One end of the reactor 30 is connected to the external terminal 18, and one end of the braking resistor 31 is connected to the external terminal 19. The changeover switch 32 selects one of the other end of the reactor 30 and the other end of the braking resistor 31 and connects to the external terminal 20 by a control signal from the host control device 33 provided in the elevator control device.

  Next, the operation of this embodiment will be described with reference to FIG. The host controller 33 receives the power failure detection signal and determines whether the commercial power source 3 has failed due to the power failure detection signal. The host controller 33 connects the other end of the braking resistor 31 to the external terminal 20 by the changeover switch 32 when an AC voltage is supplied from the commercial power supply 3 (hereinafter referred to as normal time).

  With the control circuit 12 stopping the energization signal to the relay 25, the host control device 33 closes the contactor 4. At this time, current flows from the commercial power supply 3 through the positive output terminal of the converter 7, the external terminal 18, the diode 28, the external terminal 19, the limiting resistor 24, the capacitor 8, and the negative output terminal of the converter 7. Inrush current when charging is limited. Thereafter, the control circuit 12 outputs an energization signal to the relay 25 to close the relay contact 25b.

  The battery 5 is configured by connecting a plurality of 12V or 24V batteries in series. However, the direct current voltage of the battery 5 is lower than the output voltage of the converter 7 in the normal time in order to minimize the number of batteries used for reasons such as securing the installation location of the battery 5, maintenance, and cost. For this reason, the battery 5 is electrically disconnected by the diode 29 for preventing backflow at normal times.

  The control circuit 12 outputs a PWM drive signal to the inverter 9 in order to raise and lower the car in accordance with the command received from the host controller 33. At this time, current flows from the commercial power source 3 through the positive output terminal of the converter 7, the external terminal 18, the diode 28, the external terminal 19, the relay contact 25b, the capacitor 8 and the inverter 9, and the negative output terminal of the converter 7, The electric motor 2 is driven.

  At the time of deceleration, the energy regenerated from the electric motor 2 is consumed by the braking resistor 31 to be braked. The control circuit 12 outputs an ON drive signal to the IGBT 27 when the DC voltage between the power supply lines 22 and 23 exceeds the braking threshold value. At this time, a current flows in a path from the power supply line 22 to the power supply line 23 via the external terminal 19, the braking resistor 31, the changeover switch 32, the external terminal 20, and the IGBT 27.

  FIG. 2 shows an example of a sequence when a power failure occurs in the commercial power supply 3. The operation of the control circuit 12 and the host control device 33 of the inverter device 1 is maintained by the auxiliary power supply even during a power failure. When a power failure occurs in the commercial power source 3, the DC voltage between the power lines 22 and 23 decreases, and the control circuit 12 stops the energization signal to the relay 25 and opens the relay contact 25b (step S1). At this time, current flows from the battery 5 through the switch 34, the diode 29, the diode 28, the external terminal 19, the limiting resistor 24, the capacitor 8, and the external terminal 21, and the capacitor 8 is charged by the battery 5.

  When the host controller 33 detects a power failure based on the power failure detection signal (step T1), the host controller 33 transmits a contactor 4 disconnection signal (step T2). In response to this, the contactor 4 is opened (step S2). After the contactor 4 is opened and the inverter device 1 is disconnected from the commercial power supply 3, the host control device 33 transmits a command to shift to the rescue mode to the inverter device 1 (step T3). The control circuit 12 of the inverter device 1 receives the command, shifts to the rescue mode (step S3), outputs an energization signal to the relay 25, and closes the relay contact 25b (step S4). The host controller 33 transmits a change command for the changeover switch 32 (step T4). Thereby, the changeover switch 32 is switched and the other end of the reactor 30 is connected to the external terminal 20 (step S5). Thereafter, the host controller 33 transmits a start permission signal to the inverter device 1 (step T5).

  The control circuit 12 of the inverter device 1 outputs a drive signal in which the on level and the off level are repeated to the IGBT 27 and starts boost control (step S6). When the IGBT 27 is turned on, current flows from the battery 5 through the switch 34, the diode 29, the reactor 30, the changeover switch 32, the external terminal 20, the IGBT 27, and the external terminal 21, and the current flowing through the reactor 30 increases. When the IGBT 27 is turned off, the current flowing through the reactor 30 charges the capacitor 8 through the diode 26. Thus, in the rescue mode, the reactor 30 and the braking switch circuit 11 constitute a booster circuit.

  When the DC voltage between the power supply lines 22 and 23 rises due to the boosting operation, the control circuit 12 outputs a PWM drive signal to the inverter 9 while continuing the boosting operation to drive the electric motor 2 (step S7). As a result, the car can be moved to the nearest floor by the input power from the battery 5.

  In the rescue mode, a non-boosting path is formed from the battery 5 via the switch 34, diode 29, diode 28, external terminal 19, relay contact 25b, capacitor 8, and external terminal 21 in parallel with the boosting path. When the DC voltage between the power supply lines 22 and 23 is boosted higher than the battery voltage, the voltage at the external terminal 19 is higher than the external terminal 18, so the non-boosting path is blocked by the diode 28.

  On the other hand, when the energy supply due to the boosting operation is insufficient due to a sudden increase in the motor load and the DC voltage between the power supply lines 22 and 23 is lower than the battery voltage, the voltage at the external terminal 19 is lower than the external terminal 18. Become. At this time, since the diode 28 becomes conductive, a current flows from the battery 5 to the capacitor 8 and the inverter 9 through the non-boosting path. Therefore, even when the boosting capability is insufficient due to an increase in load or the like, the DC voltage between the power supply lines 22 and 23 can be maintained substantially at the battery voltage.

  As described above, the inverter device 1 according to the present embodiment drives the electric motor 2 by boosting the voltage of the battery 5 when the commercial power supply 3 fails. Thereby, even when the battery 5 having a voltage lower than the normal input voltage (the output voltage of the converter 7) is used, the electric motor 2 can be operated with a high frequency and a high torque. As a result, the car can be moved to the nearest floor in a short time, and the people in the elevator can be rescued quickly.

  In the rescue mode executed during a power failure, the brake switch circuit 11 is used as a booster circuit. That is, the braking switch circuit 11 functions as an original braking switch that energizes the braking resistor 31 during deceleration during normal times, and functions as a boosting circuit that boosts the battery voltage during power outages. This sharing is possible because, when a power failure occurs, the car ascending / descending speed is slower than normal, and the deceleration rate of the electric motor 2 is reduced, so that braking control using the braking resistor 31 is not necessary. According to the present embodiment, the inverter device 1 having a boosting function can be configured by using the general-purpose inverter unit 6 as it is, so that the size and cost can be reduced.

(Second Embodiment)
A second embodiment will be described with reference to FIG. In the inverter device 41 of the present embodiment, the connection position of the second diode 28 is different from that of the inverter device 1 shown in FIG. That is, the cathode of the diode 28 is connected to the external terminal 18 and the external terminals 18 and 19 are short-circuited.

  A battery 5, a switch 34, and a diode 29 are connected in series between the anode of the diode 28 and the external terminal 21. One end of the reactor 30 is connected to the anode of the diode 28, and one end of the braking resistor 31 is connected to the external terminal 19, that is, the positive output terminal of the converter 7. Other circuit configurations are the same as those of the inverter device 1.

  The contents of control by the control circuit 12 are the same as in the first embodiment. According to the present embodiment, no diode is interposed in the path from the positive output terminal of the converter 7 to the capacitor 8 and the inverter 9 at the normal time when the AC voltage is supplied from the commercial power supply 3. Therefore, it is possible to reduce the loss generated in the inverter device 41 in the normal time. In addition, operations and effects similar to those of the first embodiment can be obtained.

(Third embodiment)
A third embodiment will be described with reference to FIG. The inverter device 51 of the present embodiment is also different in the connection position of the second diode 28 from the inverter device 1 shown in FIG. That is, the diode 28 is connected in series with the limiting resistor 24 between both terminals of the relay contact 25b (between the short-circuited nodes) with the converter 7 side as an anode. The external terminals 18 and 19 are short-circuited. Other circuit configurations are the same as those of the inverter device 1.

  As in the first embodiment, the normal control contents by the control circuit 12 limit the inrush current and then close the relay contact 25b to drive the motor 2. On the other hand, at the time of a power failure, the control circuit 12 does not output an energization signal to the relay 25, and executes the boost control with the relay contact 25b opened. If the relay contact 25b is closed during the step-up operation, a reverse current flows from the capacitor 8 through the relay contact 25b, the external terminal 19, the external terminal 18, the reactor 30, the changeover switch 32, the external terminal 20, and the IGBT 27. is there.

  According to the present embodiment, as in the second embodiment, no diode is interposed in the path from the positive output terminal of the converter 7 to the capacitor 8 and the inverter 9 during normal operation. Therefore, loss during normal time can be reduced. In the rescue mode during a power failure, a non-boosting path is formed from the battery 5 via the switch 34, the diode 29, the external terminal 19, the diode 28, the limiting resistor 24, the capacitor 8, and the external terminal 21 in parallel with the boosting path. Although the limiting resistor 24 is interposed in the non-boosting path, when the boosting capability is insufficient, an effect of maintaining the DC voltage between the power supply lines 22 and 23 at a value close to the battery voltage can be expected. In addition, operations and effects similar to those of the first embodiment can be obtained.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIG. The inverter device 61 of the present embodiment includes the second diode 28 at the same position as in the third embodiment. Reactor 30 is connected between external terminal 18 and external terminal 19, that is, between the positive output terminal of converter 7 and inrush current limiting circuit 10 on power supply line 22. The changeover switch 32 selects one of the one end (external terminal 19) of the braking resistor 31 and the other end of the braking resistor 31 and connects it to the external terminal 20. Other circuit configurations are the same as those of the inverter device 1.

  At the normal time, the other end of the braking resistor 31 is connected to the external terminal 20 by the changeover switch 32, and the control circuit 12 limits the inrush current and then closes the relay contact 25b to drive the motor 2. During driving of the electric motor 2, the reactor 30 suppresses the harmonic current flowing through the power supply lines 15u to 15w, so that the power factor is improved. According to this embodiment, the reactor 30 can be used effectively by using one reactor 30 for power factor improvement at the normal time and using it for boosting at the time of a power failure.

  At the time of a power failure, the external terminal 19 is connected to the external terminal 20 by the changeover switch 32, and the control circuit 12 executes the boost control with the relay contact 25b opened. This is because if the relay contact 25b is closed during the boosting operation, a short circuit occurs between the power supply lines 22 and 23 along the path of the relay contact 25b, the external terminal 19, the changeover switch 32, the external terminal 20, and the IGBT 27. Also according to the present embodiment, the same operations and effects as those of the first embodiment can be obtained.

A fifth embodiment will be described with reference to FIG. The inverter device 71 of the present embodiment has a configuration in which the braking resistor 31 and the changeover switch 32 are omitted from the inverter device 51 shown in FIG. The reactor 30 is always connected between the external terminal 19 (or the external terminal 18) and the external terminal 20. The circuit 11 corresponding to the braking switch circuit shown in FIG. 4 is not used during normal operation but is used for boosting operation during a power failure. The inverter device 71 operates in the same manner as in the third embodiment except that braking control is not performed during normal operation. If braking control is necessary, the converter 7 may be replaced with a converter having a regenerative configuration.

(Sixth embodiment)
A sixth embodiment will be described with reference to FIG. The inverter device 81 of this embodiment differs in the connection position of the battery 5 with respect to the inverter device 1 shown in FIG. That is, the positive side terminal and the negative side terminal of the battery 5 are connected to the power supply lines 15 u and 15 v via the contactors 82, respectively. The connected power lines are not limited to the U phase and the V phase. Accordingly, the third diode 29 is deleted. The contactors 4 and 82 constitute a power source selection switch 83. The host control device 33 opens the contactors 4 and 82 together, or selects and closes either one, and connects the commercial power supply 3 or the battery 5 to the input terminal 16.

  During normal operation, the contactor 4 is closed, and the other end of the braking resistor 31 is connected to the external terminal 20 by the changeover switch 32. On the other hand, in the rescue mode after a power failure, the contactor 82 is closed, and the other end of the reactor 30 is connected to the external terminal 20 by the changeover switch 32. At this time, the control circuit 12 of the inverter device 1 drives the IGBT 27 to turn on and off to perform boost control.

  When the IGBT 27 is turned on, the contactor 82 from the battery 5, the input terminal 16, the diode 7 a of the converter 7, the external terminal 18, the reactor 30, the changeover switch 32, the external terminal 20, the IGBT 27, the power line 23, the diode 7 e of the converter 7, and the input terminal 16. Current flows through the booster path of the contactor 82. When the IGBT 27 is turned off, the current flowing through the reactor 30 charges the capacitor 8 through the diode 26.

  Also in this embodiment, in parallel with the above-described boosting path, the battery 5 to the contactor 82, the input terminal 16, the diode 7a, the external terminal 18, the diode 28, the external terminal 19, the relay contact 25b, the capacitor 8, the power supply line 23, the diode 7e, A non-boosting path through the input terminal 16 and the contactor 82 is formed. When the voltage at the external terminal 19 becomes higher than the external terminal 18 due to the boosting operation, the non-boosting path is blocked by the diode 28.

  According to this embodiment, the battery voltage can be input from the input terminal 16 of the inverter device 81 under the condition of connecting the battery 5 to the inverter device 81 during the rescue mode after the power failure. Other operations and effects are the same as those of the first embodiment.

(Seventh embodiment)
A seventh embodiment will be described with reference to FIG. Inverter device 91 of this embodiment is provided with reactors 92u, 92v, and 92w in power supply lines 15u, 15v, and 15w between contactors 4 and 82 and input terminal 16 with respect to inverter device 81 shown in FIG. . The inverter device 91 uses these reactors 92u to 92w in place of the reactor 30 to perform a boosting operation, and thus the reactor 30 is unnecessary. The changeover switch 32 selects either the external terminal 18 or the other end of the braking resistor 31 and connects it to the external terminal 20. Other circuit configurations are the same as those of the inverter device 81.

  During normal operation, the contactor 4 is closed, and the other end of the braking resistor 31 is connected to the external terminal 20 by the changeover switch 32. At this time, reactors 92u to 92w are interposed on the input side of converter 7, so that the power factor can be improved. On the other hand, at the time of a power failure, the contactor 82 is closed, and the external terminal 18 is connected to the external terminal 20 by the changeover switch 32. At this time, the control circuit 12 of the inverter device 1 drives the IGBT 27 to turn on and off to perform boost control.

  When the IGBT 27 is turned on, the contactor 82, reactor 92u, input terminal 16, diode 7a, external terminal 18, switch 32, external terminal 20, IGBT 27, power supply line 23, diode 7e, input terminal 16, reactor 92v, contactor from the battery 5 are turned on. Current flows through the boosting path 82, and the current flowing through the reactors 92u and 92v increases. When the IGBT 27 is turned off, the current flowing through the reactors 92 u and 92 v charges the capacitor 8 through the diode 26. As described above, in the rescue mode, the reactors 92u and 92v and the braking switch circuit 11 constitute a booster circuit.

  According to the present embodiment, the reactors 92u to 92w can be effectively used by using the reactors 92u to 92w for power factor improvement during normal times and for boosting during a power failure. As a result, the inverter device 91 can be reduced in size and cost compared to a configuration in which a power factor improving reactor (ACL) and a boosting reactor are separately provided. In addition, operations and effects similar to those of the first and sixth embodiments can be obtained.

(Other embodiments)
In addition to the plurality of embodiments described above, the following configuration may be adopted.
In the first to fifth embodiments, other types of DC voltage sources may be used as the DC main power source instead of the converter 7 formed of a rectifier circuit.

  In the sixth embodiment, the positive terminal of the battery 5 is connected to the external terminal 18 and the negative terminal is connected to the power line 15v, or the positive terminal of the battery 5 is connected to the power line 15u, and the negative side The terminal may be connected to the external terminal 21. In the case of this connection form, the conduction diode of the converter 7 in the rescue mode can be reduced by one, so that the effect of reducing the loss can be expected. Note that the power supply line to which the terminal of the battery 5 is connected is not limited to the U phase and the V phase.

  In the seventh embodiment, a configuration in which the positive terminal of the battery 5 is connected to the external terminal 18 and the negative terminal is connected to the power supply line 15v (a connection node between the contactor 4 and the reactor 92v), or the positive side of the battery 5 The terminal may be connected to the power supply line 15u (connection node between the contactor 4 and the reactor 92u), and the negative terminal may be connected to the external terminal 21. In the case of this connection configuration, boosting is performed using any one of the reactors 92u to 92w. Since one conduction diode of the converter 7 in the rescue mode can be reduced, an effect of reducing loss can be expected. Note that the power supply line to which the terminal of the battery 5 is connected is not limited to the U phase and the V phase.

The control circuit 12 may be configured to be able to control the changeover switch 32 and the power source selection switch 83 (contactors 4, 82).
The switching element constituting the brake switch circuit 11 may be, for example, an FET or a bipolar transistor.

  The inverter apparatus of each embodiment mentioned above can be widely used for not only an elevator control apparatus but the apparatus which needs to drive a load also at the time of a power failure. The load is not limited to the electric motor.

  According to the embodiment described above, when the DC main power supply cannot supply a DC voltage due to a power failure or the like, the voltage of the DC auxiliary power supply is boosted and input to the inverter circuit, so that a high AC voltage can be output to the load. it can. At this time, since the braking switch circuit used for braking the load is used as the booster circuit, the braking switch circuit can be used effectively, and the device can be reduced in size and cost.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof in the same manner as included in the scope and gist of the invention.

  In the drawings, 1, 41, 51, 61, 71, 81, 91 are inverter devices, 2 is an electric motor (load), 5 is a battery (DC auxiliary power supply), 7 is a converter (DC main power supply, rectifier circuit), 8 is Capacitor, 9 is an inverter (inverter circuit), 10 is an inrush current limiting circuit, 11 is a braking switch circuit, 12 is a control circuit, 20 is an external terminal (braking terminal), 22 is a positive DC power line, and 23 is a negative side DC power line, 24 is a limiting resistor, 25b is a relay contact (short-circuit switch), 26 is a first diode, 27 is an IGBT (switching element), 28 is a second diode, 29 is a third diode, 30 is a reactor, 31 is Braking resistor, 32 is a changeover switch, 83 is a power source selection switch, and 92u, 92v, and 92w are reactors.

Claims (7)

Inverter circuit that outputs an AC voltage to a load, a positive DC power line connecting the output terminal of the DC main power supply and an input terminal of the inverter circuit, a negative DC power line, and a limiting resistor provided on the positive DC power line And an inrush current limiting circuit comprising a parallel circuit of a short circuit switch, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode connected to a braking terminal. In an inverter device comprising a braking switch circuit comprising a switching element connected between one diode, the braking terminal and the negative DC power supply line, and a capacitor connected in parallel with the braking switch circuit,
A second diode provided with the DC main power supply side as an anode on the positive DC power supply line between the positive output terminal of the DC main power supply and the inrush current limiting circuit;
With the DC auxiliary power supply connected in series, the positive output terminal of the DC main power supply and the positive electrode of the DC auxiliary power supply correspond between the positive output terminal and the negative output terminal of the DC main power supply. and connected, and a third diode for preventing the auxiliary DC power source is connected in the direction of discharging from the backflow, the
A reactor having one end connected to the positive output terminal of the DC main power supply;
A braking resistor having one end connected to the cathode of the second diode;
A selector switch that selects one of the other end of the reactor and the other end of the braking resistor and connects to the braking terminal;
When the DC main power supply can supply a DC voltage, the other end of the braking resistor is connected to the braking terminal by the changeover switch, and the switching element is turned on according to a predetermined braking condition to brake the load. And when the DC main power source cannot supply a DC voltage, the other end of the reactor is connected to the braking terminal by the changeover switch, and the switching element is turned on and off to change the voltage of the DC auxiliary power source. An inverter device comprising a control circuit for boost control. Inverter circuit that outputs an AC voltage to a load, a positive DC power line connecting the output terminal of the DC main power supply and an input terminal of the inverter circuit, a negative DC power line, and a limiting resistor provided on the positive DC power line And an inrush current limiting circuit comprising a parallel circuit of a short circuit switch, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode connected to a braking terminal. In an inverter device comprising a braking switch circuit comprising a switching element connected between one diode, the braking terminal and the negative DC power supply line, and a capacitor connected in parallel with the braking switch circuit,
A second diode having a cathode connected to the positive output terminal of the DC main power supply;
With the DC auxiliary power supply connected in series, the positive electrode of the DC auxiliary power supply corresponds to the anode side of the second diode between the anode of the second diode and the negative output terminal of the DC main power supply. and connected, and a third diode for preventing the auxiliary DC power source is connected in the direction of discharging from the backflow,
A reactor having one end connected to the anode of the second diode;
A braking resistor having one end connected to the positive output terminal of the DC main power supply;
A selector switch that selects one of the other end of the reactor and the other end of the braking resistor and connects to the braking terminal;
When the DC main power supply can supply a DC voltage, the other end of the braking resistor is connected to the braking terminal by the changeover switch, and the switching element is turned on according to a predetermined braking condition to brake the load. And when the DC main power source cannot supply a DC voltage, the other end of the reactor is connected to the braking terminal by the changeover switch, and the switching element is turned on and off to change the voltage of the DC auxiliary power source. An inverter device comprising a control circuit for boost control. Inverter circuit that outputs an AC voltage to a load, a positive DC power line connecting the output terminal of the DC main power supply and an input terminal of the inverter circuit, a negative DC power line, and a limiting resistor provided on the positive DC power line And an inrush current limiting circuit comprising a parallel circuit of a short circuit switch, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode connected to a braking terminal. In an inverter device comprising a braking switch circuit comprising a switching element connected between one diode, the braking terminal and the negative DC power supply line, and a capacitor connected in parallel with the braking switch circuit,
A second diode provided in series with the limiting resistor between the short-circuit nodes of the short-circuit switch with the DC main power supply side as an anode;
With the DC auxiliary power supply connected in series, the positive output terminal of the DC main power supply and the positive electrode of the DC auxiliary power supply correspond between the positive output terminal and the negative output terminal of the DC main power supply. and connected, and a third diode for preventing the auxiliary DC power source is connected in the direction of discharging from the backflow, the
A reactor having one end connected to the positive output terminal of the DC main power supply;
A braking resistor having one end connected to the positive output terminal of the DC main power supply;
A selector switch that selects one of the other end of the reactor and the other end of the braking resistor and connects to the braking terminal;
When the DC main power supply can supply a DC voltage, the other end of the braking resistor is connected to the braking terminal by the changeover switch, and the switching element is turned on according to a predetermined braking condition to brake the load. When the DC main power supply cannot supply a DC voltage, the other end of the reactor is connected to the braking terminal by the changeover switch, the short-circuit switch is turned off, and the switching element is turned on / off. An inverter device comprising: a control circuit that boosts and controls the voltage of the DC auxiliary power supply. Inverter circuit that outputs an AC voltage to a load, a positive DC power line connecting the output terminal of the DC main power supply and an input terminal of the inverter circuit, a negative DC power line, and a limiting resistor provided on the positive DC power line And an inrush current limiting circuit comprising a parallel circuit of a short circuit switch, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode connected to a braking terminal. In an inverter device comprising a braking switch circuit comprising a switching element connected between one diode, the braking terminal and the negative DC power supply line, and a capacitor connected in parallel with the braking switch circuit,
A second diode provided in series with the limiting resistor between the short-circuit nodes of the short-circuit switch with the DC main power supply side as an anode;
With the DC auxiliary power supply connected in series, the positive output terminal of the DC main power supply and the positive electrode of the DC auxiliary power supply correspond between the positive output terminal and the negative output terminal of the DC main power supply. and connected, and a third diode for preventing the auxiliary DC power source is connected in the direction of discharging from the backflow, the
A reactor provided on the positive DC power supply line between the positive output terminal of the DC main power supply and the inrush current limiting circuit;
A braking resistor having one end connected to the terminal on the inrush current limiting circuit side of the reactor;
A selector switch that selects either one of the terminal on the inrush current limiting circuit side of the reactor and the other end of the braking resistor and connects to the braking terminal;
When the DC main power supply can supply a DC voltage, the other end of the braking resistor is connected to the braking terminal by the changeover switch, and the switching element is turned on according to a predetermined braking condition to brake the load. And when the DC main power supply cannot supply a DC voltage, the switching switch connects the terminal on the inrush current limiting circuit side of the reactor to the braking terminal, turns off the short-circuit switch, and switches the switching An inverter device comprising: a control circuit for controlling the voltage of the DC auxiliary power supply to be boosted by operating an element on and off. Inverter circuit that outputs an AC voltage to a load, a positive DC power line connecting the output terminal of the DC main power supply and an input terminal of the inverter circuit, a negative DC power line, and a limiting resistor provided on the positive DC power line And an inrush current limiting circuit comprising a parallel circuit of a short circuit switch, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode connected to a wiring connection terminal an inverter device including a switch circuit consisting of switching elements connected, and a capacitor connected in parallel to the switching circuit between the first diode and the wire connection terminal and the negative-side DC power supply line,
A second diode provided in series with the limiting resistor between the short-circuit nodes of the short-circuit switch with the DC main power supply side as an anode;
With the DC auxiliary power supply connected in series, the positive output terminal of the DC main power supply and the positive electrode of the DC auxiliary power supply correspond between the positive output terminal and the negative output terminal of the DC main power supply. and connected, and a third diode for preventing the auxiliary DC power source is connected in the direction of discharging from the backflow, the
A reactor connected between the positive output terminal of the DC main power supply and the wiring connection terminal;
When the DC main power supply can supply a DC voltage, the switching element is held in an OFF state. When the DC main power supply cannot supply a DC voltage, the short-circuit switch is turned OFF and the switching element is turned ON / OFF. An inverter device comprising: a control circuit that operates and boosts the voltage of the DC auxiliary power supply. An inverter circuit that outputs an AC voltage to the load, a DC main power source that rectifies the AC power source and converts it to a DC power source, a positive DC power source line that connects the output terminal of the DC main power source and the input terminal of the inverter circuit, and a negative Side DC power supply line, an inrush current limiting circuit comprising a parallel circuit of a limiting resistor and a short-circuit switch provided on the positive side DC power supply line, and the positive side DC power supply line between the inrush current limiting circuit and the inverter circuit A brake switch circuit comprising a first diode having a cathode connected to the anode and a anode connected to a brake terminal; a switching element connected between the brake terminal and the negative DC power supply line; and the brake switch In an inverter device comprising a capacitor connected in parallel with the circuit,
A second diode provided with the DC main power supply side as an anode on the positive DC power supply line between the positive output terminal of the DC main power supply and the inrush current limiting circuit;
A reactor having one end connected to the positive output terminal of the DC main power supply;
A braking resistor having one end connected to the cathode of the second diode;
A selector switch that selects one of the other end of the reactor and the other end of the braking resistor and connects to the braking terminal;
A power source selection switch for selecting any one of the AC power source and the DC auxiliary power source and inputting it to the DC main power source;
When the power is supplied from the AC power source, the AC power source is input to the DC main power source by the power source selection switch, and when the power supply from the AC power source is stopped, the DC power source is switched by the power source selection switch. features and to Louis inverter device, further comprising a control circuit for inputting auxiliary power to the DC main power source. An inverter circuit that outputs an AC voltage to a load, a rectifier circuit that rectifies the AC voltage, a positive DC power supply line and a negative DC power supply line that connect an output terminal of the rectifier circuit and an input terminal of the inverter circuit, and the positive DC An inrush current limiting circuit comprising a parallel circuit of a limiting resistor and a short-circuit switch provided on the power supply line, a cathode connected to the positive DC power supply line between the inrush current limiting circuit and the inverter circuit, and an anode A braking switch circuit comprising a first diode connected to the braking terminal, a switching element connected between the braking terminal and the negative DC power supply line, and a capacitor connected in parallel with the braking switch circuit; In the inverter device provided,
A second diode provided on the positive DC power line between the positive output terminal of the rectifier circuit and the inrush current limiting circuit as the anode of the rectifier circuit;
A reactor having one end connected to an input terminal of each phase of the rectifier circuit;
A power source selection switch for selecting one of an AC power source and a DC auxiliary power source and connecting the other end of the reactor;
A braking resistor having one end connected to the cathode of the second diode;
A selector switch that selects one of the positive output terminal of the rectifier circuit and the other end of the braking resistor and connects it to the braking terminal;
When power is supplied from the AC power source, the AC power source is connected to the other end of the reactor by the power source selection switch, and the other end of the braking resistor is connected to the braking terminal by the changeover switch, According to a predetermined braking condition, the switching element is turned on to control braking of the load. When the power supply from the AC power supply is stopped, the DC auxiliary power source is connected to the other end of the reactor by the power source selection switch. And a control circuit that connects the positive output terminal of the rectifier circuit to the braking terminal by the changeover switch, and controls the boosting of the voltage of the DC auxiliary power supply by turning on and off the switching element. An inverter device characterized by that.

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