Elevator control device and elevator control method

Abstract

To optionally adjust drive timing for a power semiconductor element greatly changed from generation to generation to desired drive timing.SOLUTION: An elevator control device for controlling an operation of an elevator by controlling a power semiconductor element 104 for driving a motor for lifting a car comprises: a time detection unit 2263 that detects a time from outputting of a driving signal to the power semiconductor element 104 upon reception of a control command until at least one of a voltage and a current of the power semiconductor element 104 reaches a prescribed value; and a control command arithmetic unit 2262 that determines a time difference between the time detected by the delay detection unit 2263 and a reference time. The control command arithmetic unit 2262 sets a delay time from the reception of the control command to the outputting of the driving signal on the basis of information on the time difference.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an elevator control device and an elevator control method.

Background Art

[0002] In an elevator control device, for example, power semiconductor devices such as IGBT (Insulated Gate Bipolar Transistor) and MOSFET (Metal - Oxide - Semiconductor Field Effect Transistor) are used as elements for driving a motor that raises and lowers a car. When maintaining an elevator over a long period, changes in main components such as a power conversion device including the power semiconductor device used for motor drive also have a significant impact on the elevator control device. Therefore, great care is required for replacements accompanying the discontinuation of manufacturing of main components such as a power conversion device.

[0003] By the way, when the generation of a power semiconductor device such as an IGBT changes significantly, due to technological progress, characteristics such as the operating speed of the power semiconductor device are improved dramatically. Along with this, when changing the power semiconductor device of an existing elevator to a new - generation product, the drive timing changes, and it may not be possible to obtain the same control performance as in the case of the old power semiconductor device before the change. To address this, a technique has been proposed in which an appropriate gate resistance value is determined by measuring the time from when a voltage is applied to the gate terminal of the power semiconductor device until the voltage of the gate terminal reaches a voltage value equal to or higher than a predetermined threshold voltage (see, for example, Patent Document 1).

[0004] Patent Document 1 describes that "when a voltage is applied to the gate terminal of a voltage-driven semiconductor, the voltage of the gate terminal changes in proportion to the gate terminal capacitance, and the capacitance estimation method of the gate terminal capacitance based on the difference in the voltage rise time uses a counting circuit utilizing pulses of a fixed period. After applying a voltage to the gate terminal, the total number of pulse counts during the period until the voltage value reaches a threshold voltage or higher is measured. Then, the gate current of the gate drive circuit is adjusted using a gate resistance adjustment voltage proportional to the total number of pulse counts."

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the prior art described in the above Patent Document 1, due to the influence of switching losses and generated noise of the power semiconductor device, the range of selectable gate resistance values is limited, and the adjustment range of the driving timing of the power semiconductor device is also reduced. As a result, the range in which the driving timing of the power semiconductor device can be adjusted by the gate resistance value is small, and since this range is at the level of fine adjustment, it becomes difficult to arbitrarily adjust the driving timing to a desired driving timing for power semiconductor devices such as IGBTs whose operating timing varies greatly due to a large change in generation.

[0007] The present invention has been made in view of such a situation, and an object of the present invention is to provide an elevator control device and an elevator control method capable of arbitrarily setting the driving timing of a power semiconductor device to a desired driving timing when changing to a power semiconductor device whose operating timing varies greatly due to a large change in generation.

Means for Solving the Problems

[0008] The elevator control device of the present invention for solving the above problems is an elevator control device that controls the operation of an elevator by controlling a power semiconductor device that drives a motor for raising and lowering a car, and outputs a drive signal to the power semiconductor device in response to a control command, and then detects the time until at least one of the voltage and current of the power semiconductor device reaches a predetermined value, and an arithmetic unit that obtains the time difference between the time detected by this time detection unit and a reference time, and the arithmetic unit is characterized in that it sets the delay time from receiving the control command to outputting the drive signal based on the information of the obtained time difference.

[0009] Further, the elevator control method of the present invention for solving the above problems is an elevator control method that controls the operation of an elevator by controlling a power semiconductor device that drives a motor for raising and lowering a car, detects the time until at least one of the voltage and current of the power semiconductor device reaches a predetermined value after outputting a drive signal to the power semiconductor device in response to a control command, obtains the time difference between the detected time and a reference time, and sets the delay time from receiving the control command to outputting the drive signal based on the information of this time difference.

Advantages of the Invention

[0010] According to the present invention, when changing to a power semiconductor device with greatly different operation timings due to a large change in generations, the drive timing of the power semiconductor device can be arbitrarily set to a desired drive timing.

[0011] Problems, configurations, and effects other than those described above will be clarified by the description of the embodiments for carrying out the following invention (hereinafter referred to as embodiments).

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

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Figure 7

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments (embodiments) for carrying out the present invention will be described with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same function or configuration are denoted by the same reference numerals, and redundant descriptions are omitted. In addition, when there are a plurality of elements having the same or similar functions, they may be described with different subscripts attached to the same reference numeral. However, when it is not necessary to distinguish between a plurality of elements, the subscript may be omitted in the description.

[0014] <Schematic Configuration of the Main Part of an Elevator to which the Present Invention is Applied> FIG. 1 is a configuration diagram schematically showing the schematic configuration of the main part of an elevator to which the present invention is applied.

[0015] An elevator generally includes a power conversion device 100 and an elevator control device 200. The power conversion device 100 includes a converter 101 therein, and the converter 101 converts three-phase AC power output from a three-phase AC power supply 300 with a constant frequency into DC power. In addition to the converter 101, the power conversion device 100 includes a smoothing capacitor 102 and an inverter 103 therein.

[0016] In the power conversion device 100, the smoothing capacitor 102 smooths the DC power converted from the three-phase AC power by the converter 101. The inverter 103 has semiconductor elements, more specifically, power semiconductor elements 104 such as IGBTs, and converts the DC power smoothed by the smoothing capacitor 102 into three-phase AC power with a variable frequency and supplies it to the motor 400. Examples of the power semiconductor elements 104 include MOSFETs in addition to IGBTs.

[0017] The motor 400 rotationally drives the hoisting wheel 500, and operates the elevator by raising and lowering the car 700 suspended by the main rope 600 and the counterweight 800.

[0018] The elevator control device 200 controls the operation of the elevator by controlling the power semiconductor elements 104 such as IGBTs that drive the motor 400 for raising and lowering the car 700.

[0019] In the elevator with the above-described configuration, when maintaining the elevator for a long term, changes in the main components such as the power conversion device 100 including the power semiconductor elements 104 such as IGBTs used for driving the motor 400 also have a great impact on the elevator control device 200. Therefore, careful attention is required for the replacement accompanying the discontinuation of the production of the main components such as the power conversion device 100.

[0020] Incidentally, when the generation of the power semiconductor device 104 changes significantly, due to technological progress, characteristics such as the operating speed of the semiconductor device will improve dramatically. Along with this, when changing the existing power semiconductor device 104 of the elevator to a new-generation power semiconductor device, the driving timing may change, and it may not be possible to obtain the same control performance as before. The elevator control device made to address this will be described below as the elevator control device according to the reference example.

[0021] <Elevator control device according to the reference example> The reference example is an example in which a driving unit (driving board) that drives a power semiconductor device (TRS) uses a driving unit corresponding to the characteristics of the power semiconductor device to be used. FIG. 2 is a block diagram showing a configuration example of the elevator control device according to the reference example.

[0022] The elevator control device 200 according to the reference example includes a control unit 210 that controls the elevator and a driving unit 220 that drives the power semiconductor device (TRS) 104. The control unit 210 is configured as an MPU (Micro Processing Unit) board using, for example, a microcomputer 211.

[0023] In FIG. 2, the case where the power semiconductor device (TRS) 104 uses the power semiconductor device 104_A having characteristic A is illustrated. Correspondingly, as the driving unit 220, a driving unit (driving board) 220_A having a driver 221_A corresponding to characteristic A that drives the gate of the power semiconductor device 104_A is provided.

[0024] In the elevator control device 200 according to the reference example with the above configuration, when changing the power semiconductor device 104_A to a power semiconductor device 104_B having a new-generation characteristic B, in order to obtain the same control performance as before, as the driving unit 220, a driving unit 220_B having a driver 221_B corresponding to characteristic B is used. Similarly, when changing to a power semiconductor device 104_C having characteristic C, as the driving unit 220, a driving unit 220_C having a driver 221_C corresponding to characteristic C is used.

[0025] As described above, in the elevator control device 200 according to the reference example, when changing the power semiconductor element 104 to the new-generation power semiconductor elements 104_A, 104_B, and 104_C, it is necessary to change the drive unit (drive substrate) 220 to drive units 220_A, 220_B, and 220_C corresponding to the performance of the new-generation power semiconductor elements to be used. Further, in the prior art described in Patent Document 1 above, which adjusts the drive timing of the power semiconductor element by the gate resistance value, although it is not necessary to change to a drive unit corresponding to the performance of the new-generation power semiconductor element to be used, since the range in which the drive timing of the power semiconductor element can be adjusted is at the fine adjustment level, it becomes difficult to adjust the drive timing of power semiconductor elements such as IGBTs, which have a large generation change.

[0026] <Embodiment of the Present Invention> An embodiment of the present invention is an example in which when changing a power semiconductor element such as an IGBT to a power semiconductor element with a large generation change, the drive timing of the changed new power semiconductor element can be arbitrarily set to a desired drive timing. Here, as the desired drive timing, for example, the drive timing of the old power semiconductor element before changing to the new power semiconductor element with a large generation change can be exemplified.

[0027] FIG. 3 is a block diagram showing a configuration example of an elevator control device according to an embodiment of the present invention. The drive unit 220 of the power semiconductor element in the elevator control device 200 according to the present embodiment includes a timing adjustment unit 222 that sets the drive timing of the new power semiconductor element to a desired drive timing, specifically, the drive timing of the old power semiconductor element before the change, when changing the old power semiconductor element to a new power semiconductor element with a large generation change. In addition to the timing adjustment unit 222, the drive unit 220 includes a driver 223, a voltage detection unit 224, and a current detection unit 225.

[0028] The voltage detection unit 224 detects the voltage of the power semiconductor device 104, more specifically, the terminal voltage (collector voltage) of the power semiconductor device 104, and supplies it to the timing adjustment unit 222. As the voltage detection unit 224, for example, a well-known voltage detection circuit using a comparator can be exemplified. The current detection unit 225 detects the current of the power semiconductor device 104, more specifically, the current flowing through the power semiconductor device 104, and supplies it to the timing adjustment unit 222. As the current detection unit 225, for example, a well-known current detection circuit using a shunt resistor or a current sensor can be exemplified.

[0029] The timing adjustment unit 222 has the function of a time detection unit that, after receiving a control command for the power semiconductor device from the control unit 210 and outputting a drive signal for the power semiconductor device, detects the time until at least one of the detected voltage by the voltage detection unit 224 and the detected current by the current detection unit 225 reaches a predetermined value. The detected voltage by the voltage detection unit 224 is, for example, the collector voltage of the power semiconductor device. The detected current by the current detection unit 225 is, for example, the current flowing through the power semiconductor device.

[0030] The timing adjustment unit 222 further has the function of an arithmetic unit that obtains the time difference between the time detected by the function of the time detection unit and the reference time. Here, the reference time is, for example, when the driving timing of the old power semiconductor device before the change is used as a reference, the time from receiving the control command and outputting the drive signal until at least one of the voltage and current of the old power semiconductor device reaches a predetermined value. Then, the timing adjustment unit 222 sets the delay time from receiving the control command to outputting the drive signal for the new power semiconductor device based on the information of the time difference obtained by the function of the arithmetic unit, and outputs a drive signal to the new power semiconductor device via the driver 223 at the timing when this delay time has elapsed.

[0031] As described above, in the elevator control device 200 according to the present embodiment, after receiving a control command and outputting a drive signal for a power semiconductor element, the time until at least one of the detected voltage and detected current of the power semiconductor element reaches a predetermined value is detected, and the time difference between the detected time and a reference time is obtained. Then, based on the information of the obtained time difference, for the new power semiconductor element, the delay time from receiving the control command to outputting the drive signal is set, and a control command (control signal) is output to the new power semiconductor element. By this control, when changing a power semiconductor element such as an IGBT to a power semiconductor element with a significantly different operation timing due to a large change in generation, the drive timing of the new power semiconductor element after the change can be arbitrarily set to a desired drive timing without increasing the switching loss of the power semiconductor element.

[0032] In particular, by setting the reference time for obtaining the time difference based on the drive timing of the old power semiconductor element before the change, and using the time from receiving the control command to outputting the drive signal until at least one of the voltage and current of the old power semiconductor element reaches a predetermined value, even when changing to a power semiconductor element with a large change in generation, control performance equivalent to that of the old power semiconductor element can be obtained.

[0033] Also, in the case of the elevator control device 200 according to the above-described reference example, it is necessary to change the drive unit (drive board) 220 to drive units 220_A, 220_B, 220_C corresponding to the performance for each of the new-generation power semiconductor elements 104_A, 104_B, 104_C to be used. On the other hand, in the elevator control device 200 according to the present embodiment, since the drive timing of the new power semiconductor element after the change can be arbitrarily set to a desired drive timing in one drive unit 220, one drive unit 220 can correspond to new power semiconductor elements (104_A, 104_B, 104_C) with a large change in generation.

[0034] Hereinafter, specific examples for realizing the elevator control device (control method) according to the present embodiment will be described.

[0035] [Embodiment 1] Embodiment 1 Embodiment 1 of the present invention is a specific configuration example for realizing the elevator control device according to this embodiment. FIG. 4 is a block diagram showing a configuration example of the elevator control device according to Embodiment 1 of the present invention.

[0036] The drive unit 220 of the power semiconductor element in the elevator control device according to Embodiment 1 has a gate substrate 226 corresponding to the timing adjustment unit 222 in FIG. 3. The gate substrate 226 can be constituted by an FPGA (Field Programmable Gate Array) or the like. In addition to the gate substrate 226, the drive unit 220 includes a driver 223, a voltage detection unit 224, and a current detection unit 225 similar to the timing adjustment unit 222 in FIG. 3, and further includes a mode switching switch unit 227.

[0037] The mode switching switch unit 227 is a switch for switching the operation mode of the drive unit 220 under the operation by the user. Specifically, the mode switching switch unit 227 switches between a normal mode in which the elevator operates normally and an adjustment mode in which, when the old power semiconductor element is changed to a new power semiconductor element with a large generation change, the delay time from receiving a control command from the control unit 210 to outputting a drive signal for the power semiconductor element is set under the control of the gate substrate 226.

[0038] The gate substrate 226 has a configuration including an I / F circuit 2261, a control command calculation unit 2262, a time detection unit 2263, and a parameter storage unit 2264.

[0039] The I / F circuit 2261 receives a control command for the power semiconductor element 104 from the microcomputer 211 of the control unit 210, or transmits the mode information selected by the mode switching switch unit 227 to the microcomputer 211.

[0040] When the mode switch unit 227 selects the normal mode, the control command calculation unit 2262 operates the elevator normally under the control of the control unit 210. Also, when the mode switch unit 227 selects the adjustment mode, the control command calculation unit 2262 first receives a control command for the power semiconductor element 104 from the control unit 210 and outputs a drive signal for the power semiconductor element 104. This drive signal is applied to the gate of the power semiconductor element 104 via the driver 223 and the gate resistor 105, and is also given to the time detection unit 2263. A shunt resistor 106 is connected in series to the emitter side of the power semiconductor element 104. Instead of the shunt resistor 106, a current sensor or the like can also be used.

[0041] The time detection unit 2263 takes as inputs the collector voltage of the power semiconductor element 104 detected by the voltage detection unit 224 and the current flowing through the power semiconductor element 104 detected by the current detection unit 225. Then, after the control command calculation unit 2262 receives a control command (control signal) for the power semiconductor element 104 from the control unit 210 and outputs a drive signal, the time detection unit 2263 detects the time until at least one (preferably both) of the collector voltage of the power semiconductor element 104 and the current flowing through the power semiconductor element 104 reaches a predetermined value. The time information detected by the time detection unit 2263 is given to the control command calculation unit 2262.

[0042] When the time information detected by the time detection unit 2263 is, for example, based on the drive timing of the old power semiconductor element before the change, the control command calculation unit 2262 obtains the time difference between the time after receiving the control command and outputting the drive signal until at least one of the voltage and current of the old power semiconductor element reaches a predetermined value. Then, based on the obtained time difference information, the control command calculation unit 2262 sets the delay time from receiving the control command to outputting the drive signal for the new power semiconductor element, and outputs a control command (control signal) to the new power semiconductor element at the timing when this delay time has elapsed.

[0043] The information on the time difference obtained by the control command calculation unit 2262 is stored in the parameter storage unit 2264, which is an example of a storage unit. In this way, by storing the information on the time difference in a storage unit such as the parameter storage unit 2264, when the elevator is operating in the normal mode, the delay time can be set based on the information on the time difference stored in the parameter storage unit 2264. Therefore, the calculation load for obtaining the time difference can be suppressed, and a configuration that does not require real-time high-speed calculation can be achieved.

[0044] Fig. 5 shows the control signal from the control unit 210 and the change in the collector voltage of the power semiconductor element 104 in the elevator control device according to the first embodiment. First, in the old power semiconductor element before changing to a new power semiconductor element with a large generation change, when a drive signal is output in response to the control signal from the control unit 210 at time t1, the collector voltage of the old power semiconductor element reaches a predetermined value at time t3. Let the time from this time t1 to time t3 be T1.

[0045] Subsequently, in the new power semiconductor element after the change, when a drive signal is output in response to the control signal from the control unit 210 at time t1, the collector voltage of the new power semiconductor element reaches a predetermined value at time t2. Let the time from this time t1 to time t2 be T2. The control command calculation unit 2262 obtains the time difference (T1 - T2) between the time T1 at the driving timing of the old power semiconductor element and the time T2 at the driving timing of the new power semiconductor element, and performs an adjustment to delay the control signal from the control unit 210 for the new power semiconductor element by the time difference (T1 - T2). By this adjustment, the same control performance as that of the old power semiconductor element can be obtained for the new power semiconductor element.

[0046] [Second Embodiment] The second embodiment of the present invention is an example of an elevator control method in the elevator control device according to the first embodiment. The elevator control method is executed by the processing of the control unit 210 and the processing of the drive unit 220 in the elevator control device according to the first embodiment.

[0047] (Processing by the control unit) FIG. 6 is a flowchart showing an example of the processing by the control unit 210 according to the second embodiment. First, the control unit 210 checks the operation mode based on the mode information set by the mode switching switch unit 227 in the drive unit 220, and determines whether the operation mode is an adjustment mode for setting a delay time (step S11). If it is the adjustment mode (Yes in S11), the control command for the drive unit 220 is blocked (step S12), and then the process returns to step S11.

[0048] If the operation mode is not the adjustment mode for setting the delay time (No in S11), the control unit 210 determines whether there is a state abnormality in the drive unit 220. Specifically, it determines whether there is no abnormality in the drive unit 220 and whether it is in a state where the power semiconductor element 104 can be driven normally (step S13). If there is a state abnormality (No in S13), the process returns to step S11. If there is no state abnormality (Yes in S13), a control command for the drive unit 220 is generated (step S14). By generating the control command for the drive unit 220, a normal operation for operating the elevator normally is performed.

[0049] (Processing by the drive unit) FIG. 7 is a flowchart showing an example of the processing by the drive unit 220 according to the second embodiment. First, the drive unit 220 checks the operation mode based on the mode information set by the mode switching switch unit 227, and determines whether the operation mode is an adjustment mode for setting a delay time (step S21). If it is the adjustment mode (Yes in S21), the drive unit 220 determines whether there is a state abnormality. Specifically, it determines whether there is no abnormality in the drive unit 220 and whether it is in a state where the power semiconductor element can be driven normally (step S22). If there is an abnormality (No in S22), the process returns to step S21.

[0050] When it is determined that there is no abnormality in the drive unit 220 (Yes in S22), the drive unit 220 outputs a pulsed drive signal to the power semiconductor device 104 (step S23). In this drive signal output process, in order not to allow current to flow through the power semiconductor device 104 all at once, a process of gradually expanding the pulse width from a short pulse is performed.

[0051] Thereafter, based on the output of the current detection unit 225, the drive unit 220 determines whether the current flowing through the power semiconductor device 104 has risen to a predetermined current value (step S24). If it has not risen to the predetermined current value (No in S24), the process returns to step S23. If it has risen (Yes in S24), an adjustment drive pulse for adjusting the delay time is output (step S25). The pulse width of the adjustment drive pulse, for example, in the above-described example, when based on the drive timing of the old power semiconductor device before the change, corresponds to the time information from when a drive signal is output in response to a control command until at least one of the voltage and current of the old power semiconductor device reaches a predetermined value.

[0052] Subsequently, based on the voltage / current detection signals from the voltage detection unit 224 and the current detection unit 225, the drive unit 220 measures the delay (time difference) with respect to the adjustment drive pulse (step S26). Then, it generates the output timing of the drive pulse equivalent to the reference power semiconductor device from the measured time difference (step S27). Then, the information on the output timing of the generated drive pulse is stored in the parameter storage unit 2264 (step S28), and thereafter, the series of processes ends.

[0053] In step S21, when it is determined that the operation mode is not the adjustment mode, that is, when it is determined that it is the normal mode (No in S21), the drive unit 220 performs a normal operation of operating the elevator according to the control command from the control unit 210 (step S29).

[0054] By a series of processes by the drive unit 220 according to the above-described Example 2, even if the power semiconductor element is changed to one with significantly different operation timings due to a large change in the generation, control performance equivalent to that of the old power semiconductor element can be obtained.

Explanation of Reference Numerals

[0055] 100…Power conversion device, 101…Converter, 102…Smoothing capacitor, 103…Inverter, 104, 104_A to 104_C…Power semiconductor element (TRS), 105…Gate resistor, 106…Shunt resistor, 200…Elevator control device, 210…Control unit (MPU board), 211…Microcomputer (microcontroller), 220, 220_A to 220_C…Drive unit (drive board), 221_A to 221_C…Driver, 222…Timing adjustment unit, 223…Driver, 224…Voltage detection unit, 225…Current detection unit, 226…Gate board, 227…Mode switching switch unit, 300…Three-phase AC power supply, 400…Motor, 500…Counterweight, 600…Main rope, 700…Car, 800…Balance weight, 2261…I / F circuit, 2262…Control command calculation unit, 2263…Time detection unit, 2264…Parameter storage unit

Claims

1. An elevator control device for controlling the operation of an elevator by controlling a power semiconductor device that drives a motor for raising and lowering an elevator car, a time detection unit that detects the time from when a drive signal is output to the power semiconductor device in response to a control command until at least one of the voltage and current of the power semiconductor device reaches a predetermined value; an arithmetic unit that obtains a time difference between the time detected by the time detection unit and a reference time; comprising: Based on the information of the time difference, the arithmetic unit sets a delay time from when the control command is received until the drive signal is output. An elevator control device characterized by the above.

2. When the power semiconductor device is changed, when the drive timing of the old power semiconductor device before the change is used as a reference, the reference time is the time from when a control command is received and a drive signal is output until at least one of the voltage and current of the old power semiconductor device reaches a predetermined value. The elevator control device according to claim 1, characterized by the above.

3. Further comprising a storage unit that stores the information of the time difference as the information of the reference time, The arithmetic unit sets the delay time using the information of the time difference stored in the storage unit. The elevator control device according to claim 1, characterized by the above.

4. Further comprising a mode switching switch unit that can switch between a normal mode in which the elevator operates normally and an adjustment mode in which the arithmetic unit sets the delay time. The elevator control device according to claim 1, characterized by the above.

5. An elevator control method for controlling the operation of an elevator by controlling a power semiconductor device that drives a motor for raising and lowering an elevator car, detect the time from when a drive signal is output to the power semiconductor device in response to a control command until at least one of the voltage and current of the power semiconductor device reaches a predetermined value, obtain a time difference between the detected time and a reference time, Based on the information of the time difference, set a delay time from when the control command is received until the drive signal is output. An elevator control method characterized by the above.

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