JP4727095B2 - Motor power supply - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power supply device for a motor provided with an inverter that receives power supplied from a commercial AC power source and supplies AC power of variable frequency to the motor and stores regenerative power of the motor in a capacitor.
[0002]
[Prior art]
FIG. 18 shows a power supply device for a motor for driving a conventional elevator or the like disclosed in, for example, Japanese Patent Laid-Open No. 11-299275. A sheave 9 for winding a rope that suspends the elevator car 11 and the counterweight 10 is driven by a motor 7. The commercial power from the commercial AC power source 2 is supplied from the inverter 5 to the motor 7 through the smoothing capacitor 4 from the rectifier 3. When the first voltage V15 detected by the first voltage detector 15 of the smoothing capacitor 4 is equal to or higher than the predetermined first voltage V01, the regenerative power of the motor 7 is absorbed by the capacitor group 6 via the converter 13 and stored. To do. When the commercial power Pi obtained by the first voltage V15 and the first current I17 detected by the first current detection means 17 of the commercial power supply is Pm or more, the power stored in the capacitor group 6 is passed through the converter 13 Electric power is supplied to the motor 7.
[0003]
[Problems to be solved by the invention]
The conventional motor power supply apparatus is configured as described above, and energy can be saved by storing the regenerative energy of the motor 7 in the capacitor group 6 and using the stored energy for the power running operation of the motor 7. it can. However, the converter 13 is interposed between the smoothing capacitor 4 and the capacitor group 6 in order to control the feeding power and stored power of the capacitor group 6 and to prevent the voltage across the terminals of the capacitor group 6 from exceeding the withstand voltage. For this reason, there is a problem that the apparatus becomes complicated and causes a cost increase.
[0004]
The present invention was made to solve the above-described problems, and provides a power supply device for a low-cost motor that does not require a converter for power storage and power supply of a capacitor group for power storage, An object of the present invention is to provide a highly reliable motor power supply device that prevents inrush current flowing in a capacitor group.
[0005]
[Means for Solving the Problems]
In view of the above object, the present invention provides a rectifier for rectifying a commercial AC power supply, a smoothing capacitor connected in parallel to the rectifier, and an inverter connected in parallel to the smoothing capacitor and supplying AC power of variable frequency to the motor. The motor power supply apparatus includes a plurality of small unit capacitors, a capacitor group having a larger total capacity than the smoothing capacitors is provided in parallel with the smoothing capacitors, and the number of the small unit capacitors is at least equal to that of the rectifier. A current suppression means for suppressing the current flowing through the capacitor group by increasing the maximum output voltage value by a value obtained by dividing the small unit capacitor by the withstand voltage value; and according to a predetermined condition, the current suppression means is connected to the terminals of the smoothing capacitor and the capacitor. Current suppression control means connected between the terminals of the group. The current suppression unit is connected between the smoothing capacitor and the capacitor group, and the current suppression control unit detects a voltage across the capacitor group at every predetermined sampling time, and the voltage A memory for storing at least two samples of detection data of the detection means; and a switch means connected in parallel to the current suppression means, and the voltage across the terminals of the capacitor group based on the detection data stored in the memory And controlling the connection of the current suppressing means by controlling the switch means so as to suppress the current flowing through the capacitor group in accordance with the voltage change rate of the capacitor. The motor power supply device is characterized by the above.
[0011]
Further, the current suppression means is composed of a plurality of current suppression elements having different current suppression effects connected in series, and the current suppression control means includes switch means respectively connected to each current suppression element to control each of them. Features.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described according to each embodiment with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a block diagram showing a motor power supply apparatus according to Embodiment 1 of the present invention. In FIG. 1, 1 is a motor power supply device, 2 is a commercial AC power supply, 3 is a rectifier that rectifies the commercial AC power supply 2 into direct current, 4 is a smoothing capacitor, 5 is an inverter that outputs power of variable voltage and variable frequency, and 6 is Consists of small unit capacitors such as multiple electric double layer capacitors, the total capacity is set larger than the smoothing capacitor, and the number of small unit capacitors is at least the maximum output voltage value of the rectifier divided by the withstand voltage value of the small unit capacitor More capacitors are provided, 7 is a motor, 8 is a speed reducer, 9 is a sheave, 10 is a counterweight, and 11 is a car.
[0013]
Next, the operation of the motor power supply device 1 according to the first embodiment will be described. Here, an elevator is taken as an example of the motor load. In FIG. 1, the terminals P0 and N0 of the smoothing capacitor 4 and the terminals P1 and N1 of the capacitor group 6 are directly connected (between P0 and P1, and between N0 and N1). It can be considered that the voltage between N1 is equal.
[0014]
First, the charging operation during motor regeneration will be described. For example, when the car 11 is lighter than the counterweight 10, if the car 11 is to be raised, the motor 7 acts as a generator and generates regenerative power. The regenerative power generated from the motor 7 increases the voltage between the terminals P0 and N0. The smoothing capacitor 4 and the capacitor group 6 are charged with regenerative power as the voltage between the terminals P0 and N0 rises.
[0015]
Next, the discharge operation during the power running operation of the motor 7 will be described. For example, when the car 11 is heavier than the counterweight 10, if the car 11 is to be raised, the motor 7 acts as an electric motor and consumes power running power. The power running power consumed by the motor 7 drops the voltage between the terminals P0 and N0. If the voltage between the terminals P0 and N0 is higher than the DC voltage obtained by rectifying the commercial AC power supply 2 with the rectifier 3 (about DC280V in the case of AC200V), the power running power is supplied from the smoothing capacitor 4 and the capacitor group 6. The voltage between the terminals P0-N0 drops. When the voltage between the terminals P0 and N0 of the capacitor group 6 becomes equal to the DC voltage obtained by rectifying the commercial AC power supply 2 by the rectifier 3 (about DC280V in the case of AC200V), the discharge from the capacitor group 6 stops and the powering power is supplied. Switches to a commercial AC power source 2.
[0016]
Since it operates as described above, the voltage between the terminals of the capacitor group 6 (P1-N1) is always equal to or higher than a DC voltage obtained by rectifying the commercial AC power supply 2 using the rectifier 3 (in the case of AC200V, approximately DC280V). On the other hand, an electric double layer capacitor or the like which is a small unit capacitor has a withstand voltage, and must be used within a range not exceeding this. Therefore, the number of small unit capacitors connected in series as the capacitor group 6 is limited by the following expression.
[0017]
NC ≧ Vdc / Vc
NC: number of small unit capacitors, Vdc: DC voltage obtained by rectifying commercial AC power supply 2 using rectifier 3
Vc: Withstand voltage of small unit capacitor
[0018]
Here, in general, Vdc can be expressed as √2Vac with the voltage of the commercial AC power supply 2 as Vac. However, in actual application, Vdc is applied as the following equation in consideration of the variation of Vac and the efficiency of the rectifier 3.
[0019]
NC ≧ √2 (Vac + ΔV) * η / Vc
ΔV: Maximum fluctuation of voltage of commercial AC power supply 2 η: Efficiency of rectifier 3
[0020]
If the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter, or a voltage / current sensor.
[0021]
Embodiment 2. FIG.
FIG. 2 is a block diagram showing a motor power supply apparatus according to Embodiment 2 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 2, 1A is a motor power supply according to the second embodiment, R1 is a resistor connected in series to a connection line between the terminal P0 of the smoothing capacitor 4 and the terminal P1 of the capacitor group 6, and S10 is a resistor that suppresses the flowing current. Switching means connected in parallel to R1, 31 is first voltage detecting means for detecting the voltage between terminals P0 and N0 of the smoothing capacitor 4, and 32 is second voltage for detecting the voltage between terminals P1 and N1 of the capacitor group 4. A voltage detection means 21A is a determination means for operating the switch means S10 by inputting signals from the first voltage detection means and the second voltage detection means.
[0022]
Next, the operation of the motor power supply apparatus 1A according to the second embodiment will be described. At the time of initial charging, at the time of power recovery after power failure recovery, at the time of inspection, etc., the DC voltage obtained by rectifying the commercial AC power supply 2 using the rectifier 3 and the voltage between the terminals P0 and N0, the voltage between the terminals P0 and N0, and the terminals There may be a large potential difference between the voltage between P1 and N1. In such a case, a large current instantaneously flows in the capacitor group 6 and the small unit capacitor may be destroyed. Therefore, in the motor power supply device 1A, a resistor R1 and switch means S10 that can short-circuit the resistor R1 are provided in a wiring that connects one terminal of the capacitor group 6 and the smoothing capacitor 4. The motor power supply 1A includes a first voltage detecting means 31 for detecting a voltage V0 between terminals P0 and N0, a second voltage detecting means 32 for detecting a voltage V1 between terminals P1 and N1, and a voltage V0. A determination means 21A for determining the operation of the switch means S10 according to the difference ΔV (= V0−V1) of V1 is provided, and the current flowing through the capacitor group 6 is limited by opening and closing the switch means S10.
[0023]
Here, the operation of the determination unit 21A will be described. During normal power running operation and regenerative operation, the determination unit 21A closes the switch unit S10. However, when the power is turned off once due to a power failure or the like, the following procedure is performed to prevent overcurrent charging of the capacitor group 6.
[0024]
1) The determination means 21A keeps the switch means S10 closed even after the power failure is detected.
2) The switch means S10 is opened simultaneously with power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 is opened before the contactor is turned on after power recovery.)
3) When the voltage V1 between the terminals P1 and N1 rises and the difference ΔV (= V0−V1) between the voltages V0 between the terminals P0 and N0 becomes ΔV ≦ Vs1, the switch means S10 is closed and returned to the normal state. To do.
Here, 0 <Vs1.
The switch means S10 is composed of a mechanical switch, an electromagnetic switch, a contactor, and the like, and the determination means 21A is composed of a comparison circuit and a microcomputer that performs simple arithmetic processing (the same applies hereinafter).
[0025]
If the motor power supply is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter, and the voltage V1 between the terminals P1 and N1 and the voltage V0 between the terminals P0 and N0 can be obtained. Depending on the difference ΔV, it is possible to suppress the inrush current to the capacitor group 6 at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection. The second voltage detection means 32 may be constituted by voltage detection means provided for each small unit capacitor, or voltage detection means provided for each block or module of a plurality of small unit capacitors. Good.
[0026]
Embodiment 3 FIG.
FIG. 3 is a block diagram showing a motor power supply apparatus according to Embodiment 3 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 3, 1B is a power supply device for a motor according to the third embodiment, S1 and S2 are semiconductor switching elements such as transistors, D1 and D2 are diodes, 21B is a first voltage detection means 31 and a second voltage detection means 32. Is a determination means that determines whether the semiconductor switching elements S1 and S2 are conductive or nonconductive.
[0027]
Next, the operation of the motor power supply device 1B according to the third embodiment will be described. The motor power supply device 1B includes a semiconductor switching element S1 and a diode D1 that are configured to be conductive only in the direction from the smoothing capacitor 4 to the capacitor group 6 by providing a resistor R1 on the wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4. And a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1. The motor power supply 1B includes a first voltage detecting unit 31 that detects a voltage V0 between terminals P0 and N0, a second voltage detecting unit 32 that detects a voltage V1 between terminals P1 and N1, and a voltage V0. A determination means 21B for determining the operation of the semiconductor switching elements S1 and S2 by the difference ΔV (= V0−V1) of V1 is provided, and the current flowing through the capacitor group 6 is limited by the conduction and non-conduction of the semiconductor switching elements S1 and S2.
[0028]
Here, the operation of the determination unit 21B will be described. During normal power running operation and regenerative operation, the determination unit 21B makes both the semiconductor switching elements S1 and S2 conductive, and limits the current direction by the action of the diodes D1 and D2. That is, when charging the capacitor group 6, the capacitor group 6 is energized via the semiconductor switching element S1 and the diode D1. When discharging from the capacitor group 6, the smoothing capacitor 4 is energized via the semiconductor switching element S2 and the diode D2. However, when the power is turned off once due to a power failure or the like, the determination unit 21B operates in the following procedure to prevent overcurrent charging of the capacitor group 6.
[0029]
1) The determination means 21B makes both the semiconductor switching elements S1 and S2 conductive even after the power failure is detected, and corresponds to the operation at the time of the power failure.
2) At the same time as power recovery, the semiconductor switching elements S1 and S2 are made non-conductive, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power supply 2 and the rectifier 3, the semiconductor switching elements S1 and S2 are made non-conductive before the contactor is turned on after power recovery.)
3) When the voltage V1 between the terminals P1 and N1 rises and the difference ΔV (= V0−V1) from the voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs1, the semiconductor switching elements S1 and S2 are made conductive. Return to normal.
Here, 0 <Vs1.
[0030]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter, and the power supply after the initial charge, the return after a power failure, and the inspection Inrush current to the capacitor group 6 at the time of charging can be suppressed.
[0031]
Embodiment 4 FIG.
FIG. 4 is a block diagram showing a motor power supply apparatus according to Embodiment 4 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 4, 1C is a motor power supply device according to the fourth embodiment, 33 is a memory capable of storing voltage data detected by the voltage detection means 32 for at least two samplings, and 21C is a switch means S10 by inputting a signal from the memory 33. This is a determination means for determining the operation.
[0032]
Next, the operation of the motor power supply apparatus 1C according to the fourth embodiment will be described. The motor power supply device 1C is provided with a resistor R1 and a switch means S10 that can short-circuit the resistor R1 in a wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4. In addition, the motor power supply 1C includes a voltage detection unit 32 that detects a voltage between terminals P1 and N1, a memory 33 that can store detected voltage data for at least two samplings, and a current voltage V1 between terminals P1 and N1 ( n) and a determination means 21C for determining the operation of the switch means S10 based on the voltage V1 (n-1) between the terminals P1-N1 one sampling time before and the voltage change rate of the capacitor group 6 obtained from the value of the sampling time Δt. The current flowing through the capacitor group 6 is limited by opening and closing the switch means S10. In this embodiment, since the voltage change rate of the capacitor group 6 is used as the determination criterion of the determination means 21C, not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also normal regenerative charging. It can also be applied to protect the capacitor group 6 at the time and to prevent serious accidents during discharge such as a load short circuit.
[0033]
Here, the operation of the determination unit 21C will be described. First, operating conditions of the determination means 21C in normal power running operation (during discharging) and regenerative operation (during charging) are shown below.
If (1) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, the switch means S10 is opened and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1.
(2) If | (V1 (n) −V1 (n−1)) / Δt | <dVs0, the switch means S10 is closed and the current is not limited.
Here, 0 <dVs0 ≦ dVs1.
[0034]
Next, the operation procedure of the determination means 21C at the time of a power failure is shown below.
1) The determination means 21C keeps the switch means S10 closed even after a power failure is detected.
2) The switch means S10 is opened simultaneously with power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 is opened before the contactor is turned on after power recovery.)
3) If the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt <dVs0, the switching means Close S10 and return to normal.
[0035]
If the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. At the time of initial charge, after recovery from a power failure, when power is turned on after inspection In addition, the inrush current to the capacitor group 6 can be suppressed against an accident during discharging such as a normal opening operation or a load short circuit.
[0036]
Embodiment 5 FIG.
5 is a block diagram showing a motor power supply apparatus according to Embodiment 5 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 5, 1D is a motor power supply device according to the fifth embodiment, 33 is a memory capable of storing voltage data detected by the voltage detection means 32 for at least two samplings, and 21D is a semiconductor switching element that receives signals from the memory 33 as input. It is a determination means for determining the conduction and non-conduction of S1 and S2.
[0037]
Next, the operation of the motor power supply apparatus 1D according to the fifth embodiment will be described. The motor power supply device 1D includes a semiconductor switching element S1 and a diode D1 provided with a resistor R1 on a wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4 so as to be conductive only from the smoothing capacitor 4 toward the capacitor group 6. And a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1.
[0038]
The motor power supply 1D includes a voltage detection unit 32 that detects a voltage between terminals P1 and N1, a memory 33 that can store the detected voltage data for at least two samples, and a current voltage V1 between terminals P1 and N1 ( n) and the voltage V1 (n-1) between the terminals P1-N1 one sampling time before and the voltage change rate of the capacitor group 6 obtained from the value of the sampling time Δt, the determination of the operation of the semiconductor switching elements S1, S2 Means 21D are provided, and a current flowing through the capacitor group 6 is limited by conduction and non-conduction of the semiconductor switching elements S1 and S2. In the present embodiment, the capacitor group 6 is calculated from the current voltage V1 (n) between the terminals P1 and N1, the voltage V1 (n-1) between the terminals P1 and N1 one sampling time ago, and the value of the sampling time Δt. Is used as the determination criterion of the determination means 21D, so that the capacitor group 6 can be protected not only at the time of initial charging, at the time of recovery after a power failure, at the time of power-on after inspection, but also at the time of normal regenerative charging. It can also be applied to prevent serious accidents during discharge such as load short circuit.
[0039]
Here, the operation of the determination unit 21D will be described. First, the operating conditions of the determination means 21D in normal power running operation (during discharging) and regenerative operation (during charging) are shown below.
(1) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, if the semiconductor switching elements S1 and S2 are made non-conductive and the resistor R1 is energized, the current flowing through the capacitor group 6 Suppress.
If (2) | (V1 (n) −V1 (n−1)) / Δt | <dVs0, the semiconductor switching elements S1 and S2 are made conductive together, and the current direction is limited by the action of the diodes D1 and D2. That is, when charging the capacitor group 6, the capacitor group 6 is energized via the semiconductor switching element S1 and the diode D1. When discharging from the capacitor group 6, the smoothing capacitor 4 is energized via the semiconductor switching element S2 and the diode D2. At this time, current limitation is not performed.
Here, 0 <dVs0 ≦ dVs1.
[0040]
Next, the operation procedure of the determination means 21D at the time of a power failure is shown below.
1) The determination means 21D keeps the semiconductor switching elements S1 and S2 kept conductive even after the power failure is detected.
2) Simultaneously with power recovery, the semiconductor switching elements S1 and S2 are turned off, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power supply 2 and the rectifier 3, the semiconductor switching elements S1 and S2 are made non-conductive before the contactor is turned on after power recovery.)
3) If the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt <dVs0, semiconductor switching The elements S1 and S2 are turned on and returned to normal.
[0041]
If the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. At the time of initial charge, after recovery from a power failure, when power is turned on after inspection In addition, the inrush current to the capacitor group 6 can be suppressed against an accident during discharging such as a normal opening operation or a load short circuit.
[0042]
Embodiment 6 FIG.
FIG. 6 is a block diagram showing a motor power supply apparatus according to Embodiment 6 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 6, reference numeral 1E denotes a motor power supply device according to the sixth embodiment, and 21E denotes a determination unit that operates the switch unit S10 in response to an output signal of a current detection unit 34 that detects a current flowing through the capacitor group 6.
[0043]
Next, the operation of the motor power supply device 1E according to the sixth embodiment will be described. The motor power supply device 1E is provided with a resistor R1 and a switch means S10 that can short-circuit the resistor R1 in a wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4. The motor power supply device 1E includes a current detection unit 34 that detects a current value flowing between the terminals P1 and P0, and a determination unit 21E that determines the operation of the switch unit S10 based on the detected current value. The current flowing through the capacitor group 6 is limited by opening and closing. In the present embodiment, since the current value is used as the determination criterion of the determination means 21E, the capacitor group 6 is not only at the time of initial charging, at the time of recovery after a power failure, at power-on after inspection, but also at the time of normal regenerative charging. It can also be applied to protection against accidents and to prevent serious accidents during discharge such as load short circuits.
[0044]
Here, the operation of the determination unit 21E will be described. First, the operating conditions of the determination means 21E in normal power running operation (during discharging) and regenerative operation (during charging) are shown below.
(1) If I ≧ Is1, the switch means S10 is opened, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1.
(2) If I <Is0, the switch means S10 is closed and the current is not limited.
Here, it is assumed that 0 <Is0 ≦ Is1.
The current value I is an absolute value and does not indicate the direction of the current.
[0045]
Next, the operation procedure of the determination means 21E at the time of a power failure is shown below.
1) The determination means 21E keeps the switch means S10 closed even after the power failure is detected.
2) The switch means S10 is opened simultaneously with power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 is opened before the contactor is turned on after power recovery.)
3) When the current I between the terminals P0 and P1 is I <Is0, the switch means S10 is closed and the normal state is restored.
[0046]
If the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. At the time of initial charge, after recovery from a power failure, when power is turned on after inspection In addition, the inrush current to the capacitor group 6 can be suppressed against an accident during discharging such as a normal opening operation or a load short circuit.
[0047]
Embodiment 7 FIG.
FIG. 7 is a block diagram showing a motor power supply apparatus according to Embodiment 7 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 7, 1F is a motor power supply device according to the seventh embodiment, and 21F is a determination means for operating the semiconductor switching elements S1 and S2 in response to the output signal of the current detection means 34 for detecting the current flowing through the capacitor group 6. .
[0048]
Next, the operation of the motor power supply device 1F according to the seventh embodiment will be described. The motor power supply device 1F includes a semiconductor switching element S1 and a diode D1 that are provided with a resistor R1 on a wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4 so as to be conductive only from the smoothing capacitor 4 toward the capacitor group 6. And a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1. The motor power supply 1F includes a current detection unit 34 that detects a current value flowing between the terminals P1 and P0, and a determination unit 21F that determines the operation of the semiconductor switching elements S1 and S2 based on the detected current value. The current flowing through the capacitor group 6 is limited by the conduction and non-conduction of the switching elements S1 and S2. In the present embodiment, since the current value is used as the determination criterion of the determination means 21F, the capacitor group is not only at the time of initial charging, at the time of recovery after a power failure, at power-on after inspection, but also at normal regenerative charging. 6 can also be applied to prevent serious accidents during discharge such as load short circuit.
[0049]
Here, the operation of the determination unit 21D will be described. First, the operating conditions of the determination means 21D in normal power running operation (during discharging) and regenerative operation (during charging) are shown below.
(1) If I ≧ Is1, the semiconductor switching elements S1 and S2 are made nonconductive, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1.
(2) If I <Is0, the semiconductor switching elements S1 and S2 are both conducted, and the current direction is limited by the action of the diodes D1 and D2. That is, when charging the capacitor group 6, the capacitor group 6 is energized via the semiconductor switching element S1 and the diode D1. When discharging from the capacitor group 6, the smoothing capacitor 4 is energized via the semiconductor switching element S2 and the diode D2. At this time, current limitation is not performed.
Here, it is assumed that 0 <Is0 ≦ Is1.
The current value I is an absolute value and does not indicate the direction of the current.
[0050]
Next, the operation procedure of the determination means 21F at the time of a power failure is shown below.
1) The determination means 21F continues to keep the semiconductor switching elements S1 and S2 conductive even after the power failure is detected.
2) Simultaneously with power recovery, the semiconductor switching elements S1 and S2 are turned off, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. (Although not shown, when a contactor exists between the commercial power supply 2 and the rectifier 3, the semiconductor switching elements S1 and S2 are made non-conductive before the contactor is turned on after power recovery.)
3) When the current value I between the terminals P0 and P1 is I ≦ Is0, the semiconductor switching elements S1 and S2 are turned on and returned to normal.
[0051]
If the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. At the time of initial charge, after recovery from a power failure, when power is turned on after inspection In addition, the inrush current to the capacitor group 6 can be suppressed against an accident during discharging such as a normal opening operation or a load short circuit.
[0052]
Embodiment 8 FIG.
FIG. 8 is a block diagram showing a motor power supply apparatus according to Embodiment 8 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 8, 1G is a motor power supply according to the eighth embodiment, R1 and R2 are resistors connected in series between terminals P0 and P1, S10 is a switch means connected in parallel to the resistor R1, and S20 is a resistor R2. The switch means 21G connected in parallel is a determination means for determining the operation of the switch means S10 and S20 based on the signals of the voltage detection means 31 and 32.
[0053]
Next, the operation of the motor power supply device 1G according to the eighth embodiment will be described. Here, the resistance R1 ≦ R2. In the motor power supply 1G, resistors R1 and R2 are arranged in series on a wiring connecting one terminal of the capacitor group 6 and the smoothing capacitor 4, and further, switch means S10 and S20 capable of short-circuiting the resistors R1 and R2 are provided. . The motor power supply 1G includes a first voltage detecting means 31 for detecting a voltage V0 between terminals P0 and N0, a second voltage detecting means 32 for detecting a voltage V1 between terminals P1 and N1, and a voltage V0. A determination means 21G for determining the operation of the switch means S10 and S20 according to the difference ΔV (= V0−V1) of V1 is provided, and the current flowing through the capacitor group 6 is limited by opening and closing the switch means S10 and S20.
[0054]
Here, the operation of the determination unit 21G will be described. First, during normal power running operation and regenerative operation, the determination means 21G closes both the switch means S10 and S20. However, when the power is turned off once due to a power failure or the like, the following procedure is performed to prevent overcurrent charging of the capacitor group 6.
1) The determination means 21G keeps the switch means S10 and S20 closed even after the power failure is detected.
2) The switch means S10 and S20 are opened simultaneously with the power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistors R1 and R2. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 and S20 are opened before the contactor is turned on after the power recovery.)
3) When the voltage V1 between the terminals P1 and N1 rises and the difference ΔV (= V0−V1) from the voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs3, the switch means S10 is closed, and the switch means The current flowing through the capacitor group 6 is suppressed by energizing the resistor R2 with S20 opened.
[0055]
4) Further, if the voltage V1 between the terminals P1 and N1 rises and the difference in voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs2, the switch means S20 is closed, and at the same time the switch means S10 is opened. The current flowing through the capacitor group 6 is suppressed by energizing the resistor R1.
5) Further, when the voltage V1 between the terminals P1 and N1 rises and the difference in voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs1, the switch means S10 is closed, and the normal state is restored.
Here, 0 <Vs1 ≦ Vs2 ≦ Vs3.
[0056]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing in the capacitor group 6 can be changed stepwise according to the value of the voltage difference ΔV between the terminals, the capacitor group 6 is returned to the capacitor group 6 at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection. When the inrush current is suppressed, safety is high and power loss in the resistor can be reduced.
[0057]
Embodiment 9 FIG.
FIG. 9 is a configuration diagram showing a motor power supply apparatus according to Embodiment 9 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 9, 1H is a power supply device for a motor according to the ninth embodiment, R1 and R2 are resistors connected in series between terminals P0 and P1, S1, S2, S3 and S4 are semiconductor switching elements such as transistors, D1, D2, D3, and D4 are diodes, and 21H is a determination unit that determines the operation of the semiconductor switching elements S1, S2, S3, and S4 based on signals from the voltage detection units 31 and 32.
[0058]
Next, the operation of the motor power supply device 1H according to the ninth embodiment will be described. Here, the resistance R1 ≦ R2. The power supply device 1H for the motor is provided with resistors R1 and R2 in series on the wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4, and is configured to be conductive only from the smoothing capacitor 4 to the capacitor group 6 direction. A circuit composed of S1 and a diode D1, and a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1, respectively. A circuit composed of a semiconductor switching element S3 and a diode D3 configured to be conductive only in the direction of the capacitor group 6, and a circuit configured of a semiconductor switching element S4 and a diode D4 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 Are arranged in parallel with the resistor R2.
[0059]
The motor power supply 1H includes a first voltage detection unit 31 that detects a voltage V0 between terminals P0 and N0, a second voltage detection unit 32 that detects a voltage V1 between terminals P1 and N1, and a voltage V0. A determination unit 21H that determines the operation of the semiconductor switching elements S1, S2, S3, and S4 based on the difference ΔV (= V0−V1) of V1 is provided, and a capacitor group is formed by the conduction and non-conduction of the semiconductor switching elements S1, S2, S3, and S4. The current flowing to 6 is limited.
[0060]
Here, the operation of the determination unit 21H will be described. During normal powering operation and regenerative operation, the determination unit 21H makes all the semiconductor switching elements S1 to S4 conductive and limits the current direction by the action of the diodes D1 to D4. That is, when the capacitor group 6 is charged, the capacitor group 6 is energized via the semiconductor switching element S1 and the diode D1, and the semiconductor switching element S3 and the diode D3. When discharging from the capacitor group 6, the smoothing capacitor 4 is energized via the semiconductor switching element S 2 and the diode D 2, and the semiconductor switching element S 4 and the diode 4. However, when the power is turned off once due to a power failure or the like, the determination unit 21H operates in the following procedure to prevent overcurrent charging of the capacitor group 6.
[0061]
1) The determination means 21H keeps the semiconductor switch elements S1, S2, S3, and S4 conductive even after the power failure is detected.
2) The semiconductor switch elements S1, S2, S3, and S4 are made non-conductive simultaneously with the power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistors R1 and R2. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the semiconductor switching elements S1, S2, S3, and S4 are made non-conductive before the contactor is turned on after the power recovery. .)
3) When the voltage V1 between the terminals P1 and N1 rises and the difference ΔV (= V0−V1) from the voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs3, the semiconductor switching elements S1 and S2 are made conductive. By making S3 and S4 non-conductive and energizing the resistor R2 via the semiconductor switching element S1 and the diode D1, the current flowing through the capacitor group 6 is suppressed.
[0062]
4) Further, if the voltage V1 between the terminals P1 and N1 rises and the difference from the voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs2, the semiconductor switching elements S3 and S4 are turned on, and S1 and S2 are simultaneously turned on. The current flowing through the capacitor group 6 is suppressed by conducting the resistor R1 through the semiconductor switching element S3 and the diode D3.
5) Further, when the voltage V1 between the terminals P1 and N1 rises and the difference in the voltage V0 between the terminals P0 and N0 becomes ΔV ≦ Vs1, the semiconductor switch elements S1 to S4 are turned on and returned to the normal state.
Here, 0 <Vs1 ≦ Vs2 ≦ Vs3.
[0063]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing in the capacitor group 6 can be changed stepwise according to the value of the voltage difference ΔV between the terminals, the capacitor group 6 is returned to the capacitor group 6 at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection. When the inrush current is suppressed, safety is high and power loss in the resistor can be reduced.
[0064]
Embodiment 10 FIG.
FIG. 10 is a block diagram showing a motor power supply apparatus according to Embodiment 10 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 10, reference numeral 1I denotes a motor power supply device according to the tenth embodiment, 33 denotes a memory capable of storing voltage data detected by the voltage detection means 32 for at least two samplings, and 21I inputs a signal from the memory 33 to switch means S10. , Determination means for determining the operation of S20.
[0065]
Next, the operation of the motor power supply device 1I according to the tenth embodiment will be described. Here, the resistance R1 ≦ R2. In the motor power supply device 1I, resistors R1 and R2 are arranged in series on a wiring connecting one terminal of the capacitor group 6 and the smoothing capacitor 4, and further, switch means S10 and S20 capable of short-circuiting the resistors R1 and R2 are provided. . Further, the motor power supply device 1I includes a voltage detection means 32 for detecting a voltage between the terminals P1 and N1, a memory 33 capable of storing the detected voltage data for at least two samplings, and a voltage V1 between the current terminals P1 and N1 ( n) and determination means for determining the operation of the switch means S10 and S20 based on the voltage change rate of the capacitor group 6 obtained from the voltage V1 (n-1) between the terminals P1-N1 one sampling time before and the value of the sampling time Δt. 21I, and the current flowing through the capacitor group 6 is limited by opening and closing the switch means S10 and S20.
[0066]
In the present embodiment, the voltage change rate of the capacitor group 6 is used as the determination criterion of the determination means 21I. Therefore, not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also normal regenerative charging. It can also be applied to protect the capacitor group 6 at the time and to prevent serious accidents during discharge such as a load short circuit.
[0067]
Here, the operation of the determination unit 21I will be described. First, the operating conditions of the determination means 21I in normal powering operation (during discharging) and regenerative operation (during charging) are shown in FIG. 14 and will be described below. In addition, the inside of () shows the route | root in FIG.
[0068]
(1) Regardless of the state of the switch means S10 and S20, if | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs3, the determination means 21I opens the switch means S10 and S20, and the resistance By energizing R1 and R2, the current flowing through the capacitor group 6 is suppressed.
If (2) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs2 and the switch means S10 and S20 are both opened, the determination means 21I maintains the current state.
(3) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs2 and if both the switch means S10 and S20 are not open, the determination means 21I closes the switch means S10 and switches The means S20 is opened, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R2.
(4) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, and if the switch means S10 is closed and S20 is open, the determination means 21I maintains the current state.
[0069]
(5) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, and if the switch means S10 is not closed and S20 is not open, the determination means 21I opens the switch means S10, The switch means S20 is closed and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1.
(6) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs0, and if the switch means S10 is open and S20 is closed, the determination means 21I maintains the current state.
(7) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs0, and if the switch means S10 is closed and S20 is not open, the determination means 21I is closed for both the switch means S10 and S20. The current is not suppressed.
(8) If | (V1 (n) −V1 (n−1)) / Δt | <dVs0, the determination unit 21I is closed with both the switch units S10 and S20, and does not suppress the current.
Here, 0 <dVs0 ≦ dVs1 ≦≦ dVs2 ≦ dVs3.
[0070]
Next, the operation procedure of the determination means 21I at the time of a power failure is shown below.
1) The determination means 21I keeps the switch means S10 and S20 closed even after the power failure is detected.
2) The switch means S10 and S20 are opened simultaneously with the power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistors R1 and R2. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 and S20 are opened before the contactor is turned on after the power recovery.)
3) If the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs2, the switching means S10 is closed, the resistor R2 is energized, and the current flowing through the capacitor group 6 is suppressed.
[0071]
4) Furthermore, if the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs1, The switch means S20 is closed, and at the same time, the switch means S10 is regenerated and the resistor R1 is energized to suppress the current flowing through the capacitor group 6.
5) Further, if the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs0, The switch means S10 is closed and returned to normal.
Here, the switch means S10 and S20 may be mechanical switches, electromagnetic switches, contactors, or the like.
[0072]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing through the capacitor group 6 can be changed stepwise according to the voltage change rate between the terminals P1 and N1, the capacitor at the time of initial charging, at the time of recovery after a power failure, and at the time of turning on the power after inspection When the inrush current to the group 6 is suppressed, safety is high and power loss in the resistor can be reduced. Furthermore, the inrush current to the capacitor group 6 can be suppressed not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also at the time of discharge such as normal opening operation or load short circuit.
[0073]
Embodiment 11 FIG.
FIG. 11 is a configuration diagram showing a motor power supply apparatus according to Embodiment 11 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 11, 1J is a motor power supply device according to the eleventh embodiment, 33 is a memory capable of storing voltage data detected by the voltage detection means 32 for at least two samplings, and 21J is a semiconductor switch element that receives signals from the memory 33 as input. This is a determination means for determining the operations of S1, S2, S3, and S4.
[0074]
Next, the operation of the motor power supply device 1J according to the eleventh embodiment will be described. Here, the resistance R1 ≦ R2. The power supply device 1J for the motor is provided with resistors R1 and R2 in series on the wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4, and is configured to be conductive only from the smoothing capacitor 4 to the capacitor group 6 direction. A circuit composed of S1 and a diode D1, and a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1, respectively. A circuit composed of a semiconductor switching element S3 and a diode D3 configured to be conductive only in the direction of the capacitor group 6, and a circuit configured of a semiconductor switching element S4 and a diode D4 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 Are arranged in parallel with the resistor R2.
[0075]
The motor power supply 1J includes a voltage detection means 32 for detecting the voltage between the terminals P1 and N1, a memory 33 capable of storing the detected voltage data for at least two samples, and a current voltage V1 between the terminals P1 and N1 ( n) and the voltage V1 (n-1) between the terminals P1-N1 one sampling time before and the voltage change rate of the capacitor group 6 obtained from the value of the sampling time Δt, the determination of determining the operation of the semiconductor switch elements S1 to S4. Means 21J are provided, and current flowing through the capacitor group 6 is limited by conduction and non-conduction of the semiconductor switching elements S1, S2, S3, and S4 of the semiconductor switch elements S1 to S4. In this embodiment, since the voltage change rate of the capacitor group 6 is used as the determination criterion of the determination means 21J, not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also normal regenerative charging. It can also be applied to protect the capacitor group 6 at the time and to prevent serious accidents during discharge such as a load short circuit.
[0076]
Here, the operation of the determination means 21J will be described. First, the operating conditions of the determination means 21J in normal powering operation (during discharging) and regenerative operation (during charging) are shown in FIG. 15 and will be described below. In addition, the inside of () shows the route | root in FIG.
[0077]
(1) Regardless of the state of the semiconductor switching elements S1 to S4, if | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs3, the judging means 21J will disable all the semiconductor switching elements S1 to S4. The current flowing through the capacitor group 6 is suppressed by conducting the resistor R1 and R2.
If (2) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs2 and all the semiconductor switching elements S1 to S4 are non-conductive, the determination unit 21J maintains the current state.
(3) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs2 and if all the semiconductor switching elements S1 to S4 are not non-conductive, the determination unit 21J determines the semiconductor switching elements S1 and S2 The conduction, S3, and S4 are made non-conduction, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R2. At this time, the current passes through the semiconductor switching element S1 and the diode D1 when charging, and passes through the semiconductor switching element S2 and the diode D2 when discharging.
(4) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, and if the semiconductor switching elements S1 and S2 are conductive and S3 and S4 are nonconductive, the determination means 21J maintain.
[0078]
(5) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs1, and if the semiconductor switching elements S1 and S2 are not conducting and S3 and S4 are not conducting, the judging means 21J is semiconductor switching. The elements S1 and S2 are made non-conductive and S3 and S4 are made conductive, and the current flowing through the capacitor group 6 is suppressed by energizing the resistor R1. At this time, the current passes through the semiconductor switching element S3 and the diode D3 when charging, and passes through the semiconductor switching element S4 and the diode D4 when discharging.
(6) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs0, and if the semiconductor switching elements S1 and S2 are non-conductive and S3 and S4 are conductive, the determination means 21J maintain.
(7) | (V1 (n) −V1 (n−1)) / Δt | ≧ dVs0, and if the semiconductor switching elements S1 and S2 are not conducting and S3 and S4 are not conducting, the judging means 21J is semiconductor switching. All the elements S1 to S4 are made non-conductive, and the current is not suppressed.
At this time, the current passes through the semiconductor switching element S1, the diode D1, the semiconductor switching element S3, and the diode D3 when charging, and passes through the semiconductor switching element S2, the diode D2, the semiconductor switching element S4, and the diode D4 when discharging. To do.
(8) If | (V1 (n) −V1 (n−1)) / Δt | <dVs0, the judging means 21J makes all the semiconductor switching elements S1 to S4 non-conductive and does not suppress the current. At this time, the current passes through the semiconductor switching element S1, the diode D1, the semiconductor switching element S3, and the diode D3 when charging, and passes through the semiconductor switching element S2, the diode D2, the semiconductor switching element S4, and the diode D4 when discharging. .
Here, 0 <dVs0 ≦ dVs1 ≦≦ dVs2 ≦ dVs3.
[0079]
Next, operation | movement of the determination means 21J at the time of a power failure is shown.
1) The determination means 21J keeps the semiconductor switch elements S1 to S4 conductive even after the power failure is detected.
2) Simultaneously with the power recovery, all the semiconductor switch elements S1 to S4 are made non-conductive and the resistors R1 and R2 are energized to suppress the current flowing through the capacitor group 6. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, all the semiconductor switching elements S1 to S4 are made non-conductive before the contactor is turned on after power recovery.)
3) Semiconductor switching element if the voltage V1 between the terminals P1 and N1 increases and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs2. S1 and S2 are made conductive, and S3 and S4 are made non-conductive at the same time, thereby energizing the resistor R1 and suppressing the current flowing through the capacitor group 6. At this time, the current passes through the semiconductor switching element S1 and the diode D1.
[0080]
4) Furthermore, if the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs1, The semiconductor switch elements S1 and S2 are made non-conductive, and S3 and S4 are made conductive at the same time, thereby energizing the resistor R2 and suppressing the current flowing through the capacitor group 6. At this time, the current passes through the semiconductor switching element S3 and the diode D4.
5) Further, if the voltage V1 between the terminals P1 and N1 rises and the time increase rate of the voltage V1 between the terminals P1 and N1 becomes (V1 (n) −V1 (n−1)) / Δt ≦ dVs0, All the semiconductor switch elements S1 to S4 are made conductive, and return to normal.
[0081]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing through the capacitor group 6 can be changed stepwise according to the voltage change rate between the terminals P1 and N1, the capacitor at the time of initial charging, at the time of recovery after a power failure, and at the time of turning on the power after inspection When the inrush current to the group 6 is suppressed, safety is high and power loss in the resistor can be reduced. Furthermore, the inrush current to the capacitor group 6 can be suppressed not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also at the time of discharge such as normal opening operation or load short circuit.
[0082]
Embodiment 12 FIG.
FIG. 12 is a configuration diagram showing a motor power supply apparatus according to Embodiment 12 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 12, 1K is a power supply device for a motor according to the seventh embodiment, and 21K is a determination means for inputting the detection signal of the current detection means 34 and determining the operation of the switch means S10 and S20.
[0083]
Next, the operation of the motor power supply device 1K according to the twelfth embodiment will be described. Here, the resistance R1 ≦ R2. In the motor power supply 1K, resistors R1 and R2 are arranged in series on a wiring connecting one terminal of the capacitor group 6 and the smoothing capacitor 4, and switch means S10 and S20 capable of short-circuiting the resistors R1 and R2 are provided. . The motor power supply device 1K includes a current detection unit 34 that detects a current value flowing between the terminals P1 and P0, and a determination unit 21K that determines the operation of the switch units S10 and S20 based on the detected current value. The current flowing through the capacitor group 6 is limited by opening and closing S10 and S20. In the present embodiment, the voltage change rate of the capacitor group 6 is used as the determination criterion of the determination means 21K. Therefore, not only at the time of initial charging, at the time of recovery after a power failure, but at the time of power-on after inspection, normal regenerative charging is also performed. It can also be applied to protect the capacitor group 6 at the time and to prevent serious accidents during discharge such as a load short circuit.
[0084]
Here, the operation of the determination unit 21K will be described. First, the operating conditions of the determination means 21K in normal power running operation (during discharging) and regenerative operation (during charging) are shown in FIG. 16 and will be described below. In addition, the inside of () shows the route | root in FIG.
[0085]
(1) Regardless of the state of the switch means S10 and S20, if I ≧ Is3, the determination means 21K opens the switch means S10 and S20 and energizes the resistors R1 and R2, thereby supplying the current flowing through the capacitor group 6. Suppress.
(2) If I ≧ Is2 and the switch means S10 and S20 are both open, the determination means 21K maintains the current state.
(3) If I ≧ Is2 and the switch means S10 and S20 are not open, the judging means 21K closes the switch means S10, opens the switch means S20, and energizes the resistor R2, thereby allowing the capacitor group 6 Suppresses the current flowing through
(4) If I ≧ Is1, and the switch means S10 is closed and S20 is open, the determination means 21K maintains the current state.
[0086]
(5) If I ≧ Is1 and the switch means S10 is not closed and S20 is not open, the judging means 21K opens the switch means S10, closes the switch means S20, and energizes the resistor R1 to provide a capacitor. The current flowing through group 6 is suppressed.
(6) If I ≧ Is0, and the switch means S10 is open and S20 is closed, the determination means 21K maintains the current state.
(7) If I ≧ Is0 and the switch means S10 is not closed and S20 is not open, the determination means 21K is closed with both the switch means S10 and S20 and does not suppress the current.
(8) If I <Is0, the determination unit 21K closes both the switch units S10 and S20 and does not suppress the current.
Here, 0 <Is0 ≦ Is1 ≦ Is2 ≦ Is3.
The current value I is an absolute value and does not indicate the direction of the current.
[0087]
Next, the operation procedure of the determination means 21K at the time of a power failure is shown below.
1) The determination means 21K keeps the switch means S10 and S20 closed even after the power failure is detected.
2) The switch means S10 and S20 are opened simultaneously with the power recovery, and the current flowing through the capacitor group 6 is suppressed by energizing the resistors R1 and R2. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, the switch means S10 and S20 are opened before the contactor is turned on after the power recovery.)
3) When the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is2, the switch means S10 is closed, the resistor R2 is energized, and flows to the capacitor group 6 Suppresses current.
[0088]
4) Further, if the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is1, the switch means S20 is closed, and at the same time, the switch means S10 is regenerated, and the resistance R1 is energized to suppress the current flowing through the capacitor group 6.
5) Further, when the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is0, the switch means S10 is closed, and the normal state is restored.
Here, the switch means S10 and S20 may be mechanical switches, electromagnetic switches, contactors, or the like.
[0089]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing through the capacitor group 6 can be changed stepwise in accordance with the value of the current I flowing between the terminals P1 and P0, at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection When the inrush current to the capacitor group 6 is suppressed, safety is high and power loss in the resistor can be reduced. Furthermore, the inrush current to the capacitor group 6 can be suppressed not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also at the time of discharge such as normal opening operation or load short circuit.
[0090]
Embodiment 13 FIG.
FIG. 13 is a configuration diagram showing a motor power supply apparatus according to Embodiment 13 of the present invention. In the figure, the same reference numerals as those in FIG. In FIG. 13, 1L is a motor power supply according to the thirteenth embodiment, and 21L is a determination means for operating the semiconductor switching elements S1 to S4 in response to the output signal of the current detection means 34 for detecting the current flowing through the capacitor group 6. is there.
[0091]
Next, the operation of the motor power supply apparatus 1L according to the thirteenth embodiment will be described. Here, the resistance R1 ≦ R2. The power supply device 1L of the motor is provided with resistors R1 and R2 in series on the wiring connecting the capacitor group 6 and one terminal of the smoothing capacitor 4, and is configured to be conductive only from the smoothing capacitor 4 to the capacitor group 6 direction. A circuit composed of S1 and a diode D1, and a circuit composed of a semiconductor switching element S2 and a diode D2 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 are arranged in parallel with the resistor R1, respectively. A circuit composed of a semiconductor switching element S3 and a diode D3 configured to be conductive only in the direction of the capacitor group 6, and a circuit configured of a semiconductor switching element S4 and a diode D4 configured to be conductive only in the direction from the capacitor group 6 to the smoothing capacitor 4 Are arranged in parallel with the resistor R2.
[0092]
The motor power supply 1L includes a current detection unit 34 that detects a current value flowing between the terminals P1 and P0, and a determination unit 21L that determines the operation of the semiconductor switch elements S1 to S4 based on the detected current value. The current flowing through the capacitor group 6 is limited by the conduction and non-conduction of the semiconductor switching elements S1, S2, S3, and S4 of the switch elements S1 to S4. In this embodiment, since the voltage change rate of the capacitor group 6 is used as the determination criterion of the determination means 21L, not only at the time of initial charge, at the time of recovery after a power failure, and at the time of power-on after inspection, but also normal regenerative charge It can also be applied to protect the capacitor group 6 at the time and to prevent serious accidents during discharge such as a load short circuit.
[0093]
Here, the operation of the determination unit 21L will be described. First, the operating conditions of the determination means 21L in normal power running operation (during discharging) and regenerative operation (during charging) are shown in FIG. 17 and will be described below. In addition, the inside of () shows the route | root in FIG.
[0094]
(1) Regardless of the state of the semiconductor switching elements S1 to S4, if I ≧ Is3, the determination unit 21L makes all the semiconductor switching elements S1 to S4 non-conductive and energizes the resistors R1 and R2, thereby allowing the capacitor group 6 Suppresses the current flowing through
(2) If I ≧ Is2 and the semiconductor switching elements S1 to S4 are all non-conductive, the determination unit 21L maintains the current state.
(3) If I ≧ Is2 and the semiconductor switching elements S1 to S4 are not all non-conductive, the determination unit 21L sets the semiconductor switching elements S1 and S2 to be conductive and S3 and S4 to be non-conductive, and supplies the resistance R2. The current flowing through the capacitor group 6 is suppressed. At this time, the current passes through the semiconductor switching element S1 and the diode D1 when charging, and passes through the semiconductor switching element S2 and the diode D2 when discharging.
[0095]
(4) If I ≧ Is1 and the semiconductor switching elements S1 and S2 are conductive and S3 and S4 are nonconductive, the determination unit 21L maintains the current state.
(5) If I ≧ Is1 and the semiconductor switching elements S1 and S2 are not conductive and S3 and S4 are not conductive, the determination means 21L sets the semiconductor switching elements S1 and S2 nonconductive and S3 and S4 conductive, By energizing R1, the current flowing through the capacitor group 6 is suppressed. At this time, the current passes through the semiconductor switching element S3 and the diode D3 when charging, and passes through the semiconductor switching element S4 and the diode D4 when discharging.
[0096]
(6) If I ≧ Is0, the semiconductor switching elements S1 and S2 are non-conductive, and S3 and S4 are conductive, the determination unit 21J maintains the current state.
(7) If I ≧ Is0 and the semiconductor switching elements S1 and S2 are not conductive and S3 and S4 are not conductive, the determination unit 21J sets all the semiconductor switching elements S1 to S4 to nonconductive and does not suppress the current. . At this time, the current passes through the semiconductor switching element S1, the diode D1, the semiconductor switching element S3, and the diode D3 when charging, and passes through the semiconductor switching element S2, the diode D2, the semiconductor switching element S4, and the diode D4 when discharging. To do.
(8) If I <Is0, the determination unit 21J makes all the semiconductor switching elements S1 to S4 non-conductive and does not suppress the current. At this time, the current passes through the semiconductor switching element S1, the diode D1, the semiconductor switching element S3, and the diode D3 when charging, and passes through the semiconductor switching element S2, the diode D2, the semiconductor switching element S4, and the diode D4 when discharging. To do.
Here, 0 <Is0 ≦ Is1 ≦ Is2 ≦ Is3.
The current value I is an absolute value and does not indicate the direction of the current.
[0097]
Next, operation | movement of the determination means 21L at the time of a power failure is shown.
1) The determination means 21L continues to keep the semiconductor switch elements S1 to S4 conductive even after a power failure is detected.
2) The semiconductor switch elements S1 to S4 are made non-conductive simultaneously with the power recovery, and the currents flowing through the capacitor group 6 are suppressed by energizing the resistors R1 and R2. (Although not shown, when a contactor exists between the commercial power source 2 and the rectifier 3, all the semiconductor switching elements S1 to S4 are made non-conductive before the contactor is turned on after power recovery.)
3) When the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is2, the semiconductor switch elements S1 and S2 are turned on, and S3 and S4 are turned off at the same time. R1 is energized to suppress the current flowing through the capacitor group 6. At this time, the current passes through the semiconductor switching element S1 and the diode D1.
[0098]
4) Further, if the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is1, the semiconductor switch elements S1 and S2 are made non-conductive, and S3 and S4 are made conductive at the same time. The current flowing through the capacitor group 6 is suppressed by energizing the resistor R2. At this time, the current passes through the semiconductor switching element S3 and the diode D4.
5) Further, when the voltage V1 between the terminals P1 and N1 rises and the current value I between the terminals P0 and P1 becomes I ≦ Is0, the semiconductor switch elements S1 to S4 are turned on and returned to the normal state.
[0099]
When the motor power supply device is configured as described above, the capacitor group 6 can be charged / discharged without using a charge / discharge control circuit such as a converter. Further, since the current flowing through the capacitor group 6 can be changed stepwise in accordance with the value of the current I flowing between the terminals P1 and P0, at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection When the inrush current to the capacitor group 6 is suppressed, safety is high and power loss in the resistor can be reduced. Furthermore, the inrush current to the capacitor group 6 can be suppressed not only at the time of initial charging, at the time of recovery after a power failure, and at the time of power-on after inspection, but also at the time of discharge such as normal opening operation or load short circuit.
[0100]
【The invention's effect】
As described above, according to the present invention, a rectifier for rectifying a commercial AC power supply, a smoothing capacitor connected in parallel to the rectifier, and an inverter connected in parallel to the smoothing capacitor and supplying AC power of variable frequency to the motor, In the motor power supply apparatus comprising: a plurality of small unit capacitors, a capacitor group having a total capacity larger than that of the smoothing capacitor is provided in parallel with the smoothing capacitor, and the number of the small unit capacitors is at least the rectifier. The maximum output voltage value of the motor is larger than the number divided by the withstand voltage value of the small unit capacitor. Therefore, the charge / discharge control circuit such as a converter, voltage or current sensor is not used. In both cases, the capacitor can be charged and discharged.
[0101]
In addition, since current suppression means for suppressing current flowing in the capacitor group and current suppression control means for connecting the current suppression means between the terminals of the smoothing capacitor and the terminals of the capacitor group according to a predetermined condition are provided, There is an effect of suppressing the inrush current to the capacitor group at the time of charging and at the time of recovery after a power failure.
[0102]
Further, the current suppression control means controls the connection of the current suppression means so as to suppress the current flowing through the capacitor group when the difference between the smoothing capacitor terminal voltage and the capacitor group terminal voltage is greater than a predetermined value. As a result, the inrush current to the capacitor group at the time of initial charging and at the time of recovery after a power failure can be suppressed according to the difference between the voltage between the terminals of the smoothing capacitor and the voltage between the terminals of the capacitor group.
[0103]
In addition, since the current suppression control means controls the connection of the current suppression means so as to suppress the current flowing through the capacitor group according to the voltage between the terminals of the capacitor group, the current suppression control means responds to a change in the voltage between the terminals of the capacitor group. Thus, the current flowing through the capacitor group can be limited.
[0104]
Further, since the current suppression control means controls the connection of the current suppression means so as to suppress the current flowing through the capacitor group when the current value flowing through the capacitor group is equal to or greater than a predetermined value, the current flowing through the capacitor group The effect which can suppress an electric current according to is produced.
[0105]
The current suppression means includes a resistor connected in series to a connection line connecting the smoothing capacitor and the capacitor group, and the current suppression control means is connected in parallel to the resistor and is a switch that opens under a predetermined current suppression condition. Since the means is provided, the current flowing through the capacitor group can be limited by opening and closing the switch means.
[0106]
Further, the current suppression means is composed of a plurality of current suppression elements having different current suppression effects connected in series, and the current suppression control means includes switch means respectively connected to each current suppression element so as to control each. As a result, the current flowing through the capacitor group can be changed stepwise, so that the safety is high and the power loss in the resistor can be reduced.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a motor power supply apparatus according to Embodiment 1 of the present invention;
FIG. 2 is a configuration diagram showing a motor power supply apparatus according to Embodiment 2 of the present invention;
FIG. 3 is a configuration diagram showing a motor power supply apparatus according to Embodiment 3 of the present invention;
FIG. 4 is a configuration diagram showing a motor power supply apparatus according to Embodiment 4 of the present invention;
FIG. 5 is a configuration diagram showing a motor power supply apparatus according to Embodiment 5 of the present invention;
FIG. 6 is a configuration diagram showing a motor power supply apparatus according to Embodiment 6 of the present invention;
FIG. 7 is a configuration diagram showing a motor power supply apparatus according to Embodiment 7 of the present invention;
FIG. 8 is a configuration diagram showing a motor power supply apparatus according to Embodiment 8 of the present invention;
FIG. 9 is a configuration diagram showing a motor power supply apparatus according to Embodiment 9 of the present invention;
FIG. 10 is a configuration diagram showing a motor power supply apparatus according to Embodiment 10 of the present invention;
FIG. 11 is a configuration diagram showing a motor power supply apparatus according to Embodiment 11 of the present invention;
FIG. 12 is a configuration diagram showing a motor power supply apparatus according to Embodiment 12 of the present invention;
FIG. 13 is a configuration diagram showing a motor power supply apparatus according to Embodiment 13 of the present invention;
FIG. 14 is a flowchart showing an operation of a determination unit according to the tenth embodiment of the present invention.
FIG. 15 is a flowchart showing the operation of a determination unit according to the eleventh embodiment of the present invention.
FIG. 16 is a flowchart showing the operation of a determination unit according to the twelfth embodiment of the present invention.
FIG. 17 is a flowchart showing the operation of a determination unit according to the thirteenth embodiment of the present invention.
FIG. 18 is a configuration diagram showing a conventional motor power supply device.
[Explanation of symbols]
1 to 1L motor power supply device, 2 commercial AC power supply, 3 rectifier, 4 smoothing capacitor, 5 inverter, 6 capacitor group, 21A to 21L determination means, 31, 32 voltage detection means, 33 memory (storage means), 34 current detection Means, D1, D2, D3, D4 diodes, R1, R2 resistors (current suppressing means), S1, S2, S3, S4 semiconductor switch elements, S10, S20 switch means.

Claims (2)

In a motor power supply device comprising a rectifier for rectifying a commercial AC power supply, a smoothing capacitor connected in parallel to the rectifier, and an inverter connected in parallel to the smoothing capacitor and supplying AC power of variable frequency to the motor,
A plurality of small unit capacitors are provided, and a capacitor group having a larger total capacity than the smoothing capacitor is provided in parallel with the smoothing capacitor, and the number of the small unit capacitors is at least the maximum output voltage value of the rectifier. More than the number divided by the withstand voltage value of the capacitor,
Moreover the suppressing current suppressing means the current flowing through the capacitor group, setting and a current suppression control means connected between the terminals of the terminal and the capacitor group of the smoothing capacitor the current suppressing means in accordance with a predetermined condition,
The current suppression means is connected between the smoothing capacitor and the capacitor group;
The current suppression control means is
Voltage detecting means for detecting the voltage across the capacitor group at a predetermined sampling time;
A memory for storing detection data of the voltage detection means for at least two samplings;
Switch means connected in parallel to the current suppression means;
Have
Based on the detection data stored in the memory, the switch means is conductively controlled to control the connection of the current suppressing means so as to suppress the current flowing through the capacitor group according to the voltage change rate of the terminal voltage of the capacitor group. A power supply device for a motor. The current suppression means comprises a plurality of current suppression elements having different current suppression effects connected in series, and the current suppression control means includes switch means connected to each current suppression element, respectively, and controls each of them. The power supply device for a motor according to claim 1 .

Images