JP2012006715A - Elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elevator reducing a stand-by electric power upon resting and reducing consumption of a regenerative energy, thereby achieving further energy-saving.SOLUTION: A balancing weight is set heavier than a car and is set lighter than the net weight of the car upon rated loading, and upon the inactive time, the power-feeding from a power source to a DC-smoothing circuit is stopped to make a resting mode and, when being restored from the resting mode, the start of operation of an inverter is controlled in such a manner that a DC voltage value of the DC-smoothing circuit when starting the switching of the inverter becomes lower in such a case that there is the landing call on a floor upper than the floor where the car is in the stand-by state as compared to such a case that there is the landing call on a floor lower than the floor where the car is in the stand-by state in the resting mode.

Description

  The present invention relates to an elevator, and more particularly, to a technique for returning from a standby state.

  Since elevators used in condominiums have a relatively low operation rate and a long standby state, it is effective to reduce standby power for further energy saving of the elevator. As a means for reducing standby power, for example, Patent Document 1 describes one that cuts off power supply to a power converter and a control power supply circuit while an elevator is on standby. However, in the technique of Patent Document 1, the voltage of the DC smoothing circuit decreases during standby, and it takes time to reach the voltage necessary for driving the elevator by charging it when returning. On the other hand, in patent document 2, it has the circuit which charges a direct current smoothing circuit separately, and the return from a standby state is accelerated and the fall of a service is suppressed.

  Non-Patent Document 1 describes an electric double layer capacitor used in a DC smoothing circuit and a storage device having a large capacity. It also describes storing regenerative energy in a capacitor of a DC smoothing circuit.

JP 2001-2335 A JP 2006-36399 A

Load leveling method for electric double-layer capacitor storage type elevator (Yusuke Ota et al. 2009 IEEJ Industrial Application Division Conference 1-84)

  However, in Patent Document 1, as already described, the voltage of the DC smoothing circuit decreases during standby, and it is charged at the time of return, and it takes time to reach the voltage required for driving the elevator. There is a problem that it takes time.

  Further, in Patent Document 2, although the return from the standby state is accelerated, there is a problem that standby power reduction is not sufficient because the DC smoothing circuit is charged even during standby.

  Further, as in Non-Patent Document 1, when a large-capacity capacitor is used in the DC smoothing circuit, the voltage drop rate of the DC smoothing circuit during standby becomes slow, so the time from standby start to return is short. In this case, the influence of the voltage drop is small. However, when a long time has passed since the start of standby, it still takes time to charge at the time of return, and there is a problem that it takes time to return. In addition, there is a problem that increasing the capacity of the capacitor leads to an increase in the size of the device. In addition, when there is a large amount of regenerative energy, there is also a problem that power cannot be stored in the capacitor and is consumed by resistance.

  The problem to be solved by the present invention is to provide an elevator capable of reducing standby power at rest and reducing consumption of regenerative energy and further saving energy.

  In addition, other problems other than the above-described problems will be made clear from the entire description of the present specification or the drawings.

  In order to solve the above problems, in the elevator according to the present invention, the counterweight is a weight that is heavier than the car and lighter than the total weight of the car when the rated load is applied. The DC voltage value of the DC smoothing circuit when starting the inverter switching is lower than the floor where the car is waiting during the sleep mode. The operation start of the inverter is controlled so as to be lower when there is a landing call on the floor above the floor on which the car is waiting than when there is a landing call on the other floor.

  The above-described configuration is merely an example, and the present invention can be modified as appropriate without departing from the technical idea. Further, examples of the configuration of the present invention other than the above-described configuration will be clarified from the entire description of the present specification or the drawings.

  ADVANTAGE OF THE INVENTION According to this invention, while reducing standby electric power at the time of a stop, consumption of regenerative energy can be reduced and a further energy saving can be aimed at. Other effects of the present invention will become apparent from the description of the entire specification.

The figure which shows the structure of Example 1 of this invention. The figure which shows the flow which returns from standby in Example 1 of this invention. The figure which shows the aspect of the change of the DC voltage in Example 1 of this invention. The figure which shows the structure of Example 2 of this invention. The figure which shows the flow which returns from standby in Example 2 of this invention. The figure which shows the aspect of the change of the DC voltage in Example 2 of this invention. The figure which shows the component of Example 1 of this invention. The figure which shows the component of Example 3 of this invention. The figure which shows the structure of Example 4 of this invention.

  Embodiments of the present invention will be described with reference to the drawings. In each drawing and each embodiment, the same or similar components are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 1 shows a schematic configuration of an elevator according to Embodiment 1 of the present invention. A typical rope type is used as an example of the elevator structure, and a balance weight 6 of a weight that is balanced when about half of the rated load is placed on the car 5 and the car is connected via a rope 7. Is driven by a hoisting machine 4. Note that the weight of the counterweight 6 is merely an example, and a weight that is heavier than the car 5 and lighter than the total car weight when rated loading can be used.

  The elevator drive control device 1 is connected to a power source 2, and a rectifier circuit 13 with a power limiting function is connected from the power source 2 via a main power switch 3, a switch 11 and a filter reactor 12, and AC power from the power source is connected. Is converted to DC power. Here, an example is shown in which a thyristor phase control circuit is used as the rectifier circuit 13 with the power limiting function, and the power supply from the power source is limited by the firing angle of the thyristor, and the DC voltage is low when the power is turned on. Inrush current is suppressed. Then, the elevator drive control device 1 smoothes the converted DC power by a DC smoothing capacitor 14 that is a DC smoothing circuit, converts this to DC power as a DC power source, and converts it into AC power of variable voltage / variable frequency by the elevator 15. The elevator is driven and controlled by supplying it to the motor of the hoisting machine 4. As the DC smoothing capacitor 14, an electric double layer capacitor may be used as in Non-Patent Document 1, or another capacitor may be used.

  A so-called brake resistor 161 and a brake switch 162 are connected to the elevator drive control device 1 in parallel with the DC smoothing capacitor 14 to prevent overvoltage when the regeneration mode is set. Further, when the brake switch 162 is turned off, a diode 163 is connected in antiparallel with the brake resistor 161 in order to suppress the jumping voltage due to the wiring inductance of the brake resistor 161 and the brake switch 162. For example, in the regenerative mode in which a passenger with a rated load is riding on the car 5, regeneration occurs due to the potential energy, and the voltage of the DC smoothing capacitor 14 (simply called DC voltage) increases. When the DC voltage rises to a set value (brake switch input voltage) that takes into account the rated voltage of the DC smoothing capacitor 14 and the rated voltage of the switching elements constituting the inverter 15, the brake switch control unit 182 turns on the brake switch 162. By connecting the brake resistor 161, energy is consumed as heat by this resistor, thereby suppressing a voltage increase of the DC voltage. Moreover, the brake switch control part 182 will turn off the brake switch 162, if DC voltage falls to the brake switch open | release voltage lower than brake switch input voltage.

  Further, the rectifier circuit 13 with a power limiting function limits power feeding from the power source by performing phase control with the power feeding control unit 181. FIG. 7 shows a configuration example of the rectifier circuit 13 with a power limiting function. FIG. 7 shows a case where a three-phase AC power source is used as the power source 2 and a three-phase phase control circuit is used as the rectifier circuit 13 with a power limiting function, as in the example of FIG. Yes. The main power switch 3, the switch 11 and the filter reactor 12 are also composed of three phases, and the phase control circuit is composed of six thyristor switches 1311 to 1316. In an elevator, power is often supplied from a three-phase AC power source, which is the most common configuration example.

  The power conversion circuit control unit 18 and the elevator control unit 10 are supplied with electric power necessary for control from the control power source 171. The control power source 171 is supplied from the power source 2 via a transformer, a rectifier circuit, and a smoothing circuit (not shown), for example. Power supply system and a system for supplying power from the DC smoothing capacitor 14 via a voltage conversion circuit (DC / DC converter) 172. For example, the DC voltage is low and DC is low immediately after the power is turned on. Power is supplied from the power source 2 in a state where the DC / DC converter 172 cannot sufficiently supply power. When the voltage of the DC smoothing capacitor 14 exceeds the voltage necessary for the DC / DC converter operation, power is supplied from the DC voltage via the voltage conversion circuit 172. The voltage conversion circuit 172 is also connected with a resistor of about 10 to 100 kΩ for discharging the residual charge of the DC smoothing capacitor 14 when the power is cut off. For example, the DC voltage does not remain when parts are replaced. Yes.

  The elevator control unit 10 is a part that controls the entire elevator, but only the part related to the present invention is shown here. The operation control unit 101 exchanges control information with the power conversion circuit control unit 18 so that a desired operation can be performed from the information on the car 5 and the hall call information on each floor.

  The elevator control unit 10 performs the next operation from the hall call information from the hall call devices 8B, 81 to 8N on each floor from the first basement floor to the ground N floor and information indicating the state of the car 5 such as the position and loading information. Is determined by the operation mode determination unit 102, the operation start voltage Vst in the inverter operation start control unit 103 is switched to V1 or V2, and the operation start voltage Vst is compared with the DC voltage Vdc. Is equal to or higher than Vst, an operation start signal is sent to the inverter control unit 183. The switching of the inverter operation start voltage Vst will be described later with reference to FIG. In addition, the operation mode determination unit 102 of the elevator control unit 10 uses the information on the car 5 such as the hall call information and the loading information of the car 5 to make it quiet when there is no use for a certain period of time (approximately several minutes or more). Be able to judge.

  Next, the operation when the elevator is quiet will be described with reference to FIG. As in the case of the prior art, in the off-season (1001), for example, the switch 11 such as an electromagnetic contactor is opened, and the rectifier circuit 13 with the power limiting function and the inverter 15 are stopped in order to set the sleep state. The standby power is reduced (1002). Accordingly, power supply from the power source 2 to the DC smoothing capacitor 14 is also stopped. Even in this state, since the elevator control unit 10 continues to have a part of the functions, the DC voltage Vdc decreases with time because the power consumption is small compared with the operation (1003). Note that the progress of the decrease in the DC voltage Vdc varies depending on the capacity and voltage of the DC smoothing capacitor 14, and becomes considerably slow when an electric double layer capacitor or the like is connected as in the example of Non-Patent Document 1. .

  Although not shown in the figure, when the power supply from the power source 2 has been stopped for a long time, when the DC voltage Vdc drops to a voltage that the voltage conversion circuit 172 cannot operate, the switch 11 is turned on for control. This can be done by supplying power from the power source 2 via the power source 171.

  For example, let us consider a case (1004) where a landing call is generated on the k-th floor above the car 5 while the car 5 is stopped on the first floor as shown in FIG. Thus, since the operation of the elevator is resumed, the switch 11 is turned on and the rectifier circuit 13 with a power limiting function is activated to charge the DC smoothing capacitor 14 (1005). As a result, the DC voltage Vdc increases (1006).

  On the other hand, the operation mode determination unit 102 determines whether the operation at the time of returning from the stop is power running or regeneration (1007), and switches the operation start voltage Vst of the inverter 15 to V1 or V2. Here, the car 5 is empty because it is a return from the stop, and the empty car 5 rises from the standby floor (the first floor) of the car 5 to the k floor above it, so Since the counterweight 6 that is heavier than the car 5 is lowered, the regeneration mode is set, so that the operation start voltage Vst of the inverter 15 is set to V1 (1008a). On the other hand, if the empty car 5 is lowered when the driving for returning from the stop is, for example, when there is a landing call on the floor below the standby floor of the car 5 in the stop state. In order to enter the power running mode, the operation start voltage Vst of the inverter 15 is set to V2 higher than V1 (1008b). Here, the operation start voltage Vst of the inverter 15 is switched between V1 and V2 depending on whether the operation mode is the regeneration mode or the power running mode when the inverter is started when returning from the stop. The reason will be described later.

  In the inverter control unit 183, when the DC smoothing capacitor 14 is charged, the DC voltage Vdc rises (1006), and when the inverter starter voltage Vst is equal to or higher than the operation start voltage Vst (Vdc ≧ Vst) (1009), the inverter 15 starts operating. The elevator brake is released (1010), and the elevator car 5 starts to be lifted (return from rest).

  In order to prevent the elevator from moving at the moment of brake release due to the difference in mass between the car 5 and the counterweight 6, a torque is applied to the hoist 4 by power supply from the inverter 15 before the brake is released. Start-up compensation is made. Even in the case of a hall call in the regenerative mode in which the empty car 5 rises as in this example, a DC voltage higher than V1 is required because the startup compensation period is in the power running mode. Here, when the empty car 5 waiting in the rest state is called on another floor and moves, there is no passenger, so there is no problem even if it suddenly starts immediately after the brake is released, We decided not to compensate for start-up when the car 5 is empty. Thereby, in the regeneration mode, the operation start voltage Vst of the inverter 5 can be made lower than in the power running mode.

  In addition, as a means of knowing the passengers in the car 5, recently, in addition to sensors that measure the mass in the car, image recognition by a camera has become widespread, and the presence or absence of passengers can be reliably detected. When it is detected that the car is an empty car 5 other than the return from the resting state, the start-up compensation may not be performed.

  FIG. 3 shows schematic changes in the DC voltage Vdc, the switch 11 input command, the operation command of the rectifier circuit 13 with the power limiting function, the inverter 15 operation permission, the brake switch 162 input command, the torque command, and the speed command. At time t0, the operation control unit 101 of the elevator control unit 10 determines that it is quiet because a certain time has elapsed since the last elevator operation, and turns off the switch 11 and operates the rectifier circuit 13 with a power limiting function. To stop and enter hibernate mode. As a result, standby power during a pause can be reduced. Although not shown, the operation of the inverter 15 is also stopped during standby.

  Since the power supply from the power source 2 is stopped, the DC voltage Vdc decreases, and Vdc <V2 at time t1, so that the inverter 15 cannot be restarted as it is (the operation permission signal of the inverter 15 is shown in the figure). Off).

  Assume that a landing call is generated on the k-th floor above the floor on which the car 5 is waiting at the time t2 when the DC voltage is lowered while the power supply is shut off for a long time. In response to the landing call, the operation control unit 101 of the elevator control unit 10 turns on the switch 11 in order to recover from standby, and also operates the rectifier circuit 13 with a power limiting function. As a result, the DC smoothing capacitor 14 is charged and the DC voltage Vdc rises. At this time, the operation mode determination unit 102 determines the regeneration mode in which the empty car 5 that has been on standby rises, and the inverter operation start control unit 103 determines the operation start voltage Vst = V1 (where V1 is greater than V2). Switch to a lower voltage.

  At time t3, since DC voltage Vdc ≧ operation start voltage Vst (V1), the operation permission of the inverter 15 is turned on, and the operation of the inverter 15 is started by the inverter control unit 183, and the inverter is activated according to the torque command and the speed command. 15 is switching-controlled. At this time, since there are no passengers, the brakes are released without starting compensation, and the car 5 moves according to the speed command. The speed command is generally moderated immediately after stopping and immediately before reaching a constant speed, but is simplified and shown as a straight line in the figure.

  If the operation start voltage Vst of the inverter 15 is kept at V2, the DC voltage Vdc changes as shown by the dotted line from t3 to t4 in FIG. 3, and the operation start time of the inverter 15 is t4. The movement starts late, and the arrival of passengers at the k-th floor is delayed compared to the case where movement starts at t3. That is, since torque is required in the power running mode, it is necessary to set the operation start voltage Vst to V2. However, in the regenerative mode, torque is not required as compared to the power running mode, so the operation is started. The voltage Vst can be set to V1, which is lower than the case of V2 required in the power running mode, whereby the operation start time of the inverter 15 can be set to a time t3 earlier than the time t4. Can be made faster.

  Immediately after the start of the operation of the inverter 15, the rise of the DC voltage Vdc is suppressed, but as the speed increases, the regenerative power generated by the lowering of the counterweight 6 heavier than the empty car 5 increases. The voltage rises. At time t5, the DC voltage Vdc becomes equal to or higher than the brake switch input setting voltage Vdon, the brake switch 162 is turned on, and excess regenerative power is consumed as heat. As a result, the DC voltage Vdc decreases. When the speed is reduced and the regenerative power decreases, the DC voltage Vdc becomes equal to or lower than the brake switch opening set voltage Vdoff at time t6, so that the brake switch 162 is opened. Note that the change in DC voltage when the brake switch 162 is turned on varies depending on the resistance value of the brake resistor 161, and the time t6 varies depending on voltage setting values such as Vdon and Vdoff.

  Thereafter, at time t7, the car 5 arrives at the k-th floor and moves up and down according to the destination registration of the passenger who has boarded the car. Note that the operation start voltage Vst is returned to the setting of V2 in order to perform start-up compensation even in the regenerative mode thereafter.

  With such a configuration, the standby power can be reduced during a stop, and when returning from the stop, a time t4 is given to a passenger call on a floor above the floor on which the elevator is waiting. And the time can be shortened by the difference between time t3. Further, by setting the setting value of the operation start voltage Vst of the inverter 15 to V1, which is lower than V2, the energy stored in the DC smoothing capacitor 14 until the DC voltage Vdc changes from V1 to Vdon is stored from V2 to Vdon. Therefore, the energy consumed by the brake resistor 161 can be reduced, which can contribute to the energy saving of the elevator.

  In general elevators, the frequency of use is low except in the morning and evening hours, and there are many cases where the elevator is in a quiet state. In this case, the elevator is often on the first floor as a reference floor. At this time, if there are passengers on any floor on the ground, the effect of shortening the waiting time and reducing energy consumption can be expected.

  In the first embodiment, it is not essential that the rectifier circuit 13 with the power limiting function has the power limiting function. Therefore, the configuration of the general rectifier circuit 13 may be used.

  Further, it is not essential that start-up compensation is not performed, and it may be performed. However, in this case, power is consumed somewhat, but energy is saved as compared with the case where Vst = V2.

  In FIG. 4, the schematic structure of the elevator in Example 2 of this invention is shown. Although almost the same as FIG. 1, in this example, the operation mode determination unit 102 determines the operation mode when returning from the standby state and switches the set value of the operation start voltage Vst of the inverter 15 to V1 or V2. At the same time, a command is sent to the power supply control unit 181 to change the current command.

  FIG. 5 shows the flow at this time, and FIG. 6 shows changes in the DC voltage Vdc. 5 is different from FIG. 2 in that the operation start voltage Vst = V1 is set for the inverter 15 during regeneration, the charging current Iso = I1 is set (1008c), and the inverter 15 is set for power running. The operation start voltage Vst = V2 is set (V1 <V2), and the charging current Iso = I2 is set (I1 <I2) (1008d).

  In FIG. 6, the difference from FIG. 3 will be described. When a call from the k-th floor occurs at time t2, the regeneration mode is set as in the first embodiment, so that the operation start voltage Vst of the inverter 15 becomes Vst = V1. It is possible to reduce the power from the power source 2 by setting and reducing the charging current Iso of the rectifier circuit 13 with the power limiting function to I1. In this case, the increase in the DC voltage Vdc becomes gentler than that in the case where the DC voltage Vdc is not limited, and reaches V1 at the time t4 when the operation start voltage V2 of the inverter 15 is set as usual and the charging current Iso = I2 is set. Therefore, the operation start time of the inverter 15 and the time t10 arriving at the k-th floor are not changed and the time is not shortened, but the power supplied from the power source 2 is reduced and the consumption at the brake resistor 161 is reduced. Since there exists an effect which reduces electric power, it can contribute to the energy saving of an elevator. Note that the operation start time of the inverter 15 in the regeneration mode can be set between the time t3 and the time t4 by making the limit of the charging current Iso looser than that in the case of FIG. The effect of shortening can also be obtained.

  In FIG. 8, the component in Example 3 of this invention is shown. FIG. 8 shows a configuration in which a three-phase AC power source is used as the power source 2, a rectifier circuit 13 with a power limiting function, and a step-up chopper circuit is combined with a diode rectifier circuit as in the example of FIG. is there. The rectifier circuit is composed of six diodes (1321 to 1326) and a filter capacitor 133, and the boost chopper circuit is composed of a chopper switch 134, an antiparallel diode 136, a chopper reactor 135, and a polarity limiting diode 137.

  While the phase control circuit of FIG. 7 requires six control signals, the control signal in the case of FIG. 8 is only one chopper switch 134, and the signal system is simplified.

  FIG. 9 shows a configuration according to the fourth embodiment of the present invention. Here, the power source 2 uses a single-phase power source, and the rectifier circuit 13 with a power limiting function uses a phase control circuit using thyristors 1311 to 1314. In addition, a plurality of electric double layer capacitors are connected in series to the DC smoothing capacitor portion, and here, 5 series (1411 to 1415) are provided. Since the electric double layer capacitor has a larger capacitance than a general electrolytic capacitor or the like, it is possible to suppress the pulsation of the DC voltage even when the power source is not a three-phase but a single phase. On the other hand, in many cases, for example, parallel resistors (1421 to 1425) are connected so that the voltage sharing between the series is equal, and even if there is a difference in capacitance, the non-uniformity is often suppressed. Due to the large capacitance, the voltage drop during power shutoff is gradual, but there is also a resistance to equalize the voltage sharing, so the DC voltage drops when the power is shut off for a certain period of time, so it is charged when returning At that time, it is possible to reduce the time required for the return by doing as shown in FIG.

  In addition, the increase in DC voltage during regeneration is slow because the capacitance is large, but if the capacitance is increased in order to reduce the power consumption in the brake resistor 161, the electric double layer capacitor becomes larger and the size of the device increases. Therefore, energy saving can be achieved by setting a low DC voltage at the start of the operation that is in the regenerative mode as shown in FIGS.

  The present invention has been described using the embodiments. However, the configurations described in the embodiments so far are only examples, and the present invention can be appropriately changed without departing from the technical idea. Further, the configurations described in the respective embodiments may be used in combination as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1 Elevator drive control apparatus 2 Power supply 3 Main power switch 4 Hoisting machine 5 Car 6 Balance weight 7 Rope 8B, 81, 82, 8k, 8N Landing call apparatus 10 Elevator control part 11 Switch 12 Filter reactor 13 With power limiting function Rectifier circuit 14 DC smoothing capacitor 15 Inverter 18 Power conversion circuit control unit 101 Operation control unit 102 Operation mode determination unit 103 Inverter operation start control unit 151 Current sensor 161 Brake resistor 162 Brake switch 163 Diode 171 Control power source 172 Voltage conversion circuit 181 Power supply control 182 Brake switch controller 183 Inverter controller

Claims (5)

In an elevator having a car, a counterweight connected to the car via a rope, a hoisting machine that drives the car, and an elevator drive control device that drives the hoisting machine,
The counterweight is a counterweight that is heavier than the car and lighter than the total car weight when rated loading,
The elevator drive control device includes a rectifier circuit that converts AC power from a power source into DC power, an inverter that converts the DC power into AC power and supplies the AC power, and the rectifier circuit and the inverter. A DC smoothing circuit provided in between, and an elevator control unit;
The elevator control unit is configured to stop the power supply from the power source to the DC smoothing circuit when it is quiet and to set the sleep mode, and the DC when starting the switching of the inverter when returning from the sleep mode. The DC voltage value of the smoothing circuit is higher in the floor above the floor on which the car is waiting than when there is a landing call on the floor below the floor on which the car is waiting in the sleep mode. An elevator having an inverter operation start control unit that controls the start of operation of the inverter so as to be lower when there is a landing call.   In Claim 1, when returning from the said sleep mode, the said car is waiting rather than the case where there is a landing call in the floor below the floor where the said car is waiting during the said sleep mode. The elevator characterized in that the time from the start of power feeding to the DC smoothing circuit to the start of switching of the inverter is shorter when there is a landing call above the floor.   3. When returning from the suspension mode according to claim 2, when there is a landing call on a floor below the floor where the car is waiting during the suspension mode, and from the floor where the car is waiting The elevator characterized in that the magnitude of the current supplied to the DC smoothing circuit is the same as when there is a hall call on the upper floor.   In claim 1, when returning from the pause mode, when there is a landing call on a floor below the floor where the car is waiting during the pause mode, and from the floor where the car is waiting An elevator characterized in that the time from the start of power feeding to the DC smoothing circuit to the start of switching of the inverter is the same when there is a hall call on the upper floor.   In any one of Claims 1, 2, and 4, when returning from the sleep mode, than when there is a hall call on a floor below the floor on which the car is waiting during the sleep mode, The elevator characterized in that the magnitude of the current supplied to the DC smoothing circuit is smaller when there is a landing call on the floor above the floor where the car is waiting.

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