JP7845513B2 - Elevator temperature estimation system - Google Patents

Description

This disclosure relates to an elevator temperature estimation system.

Patent Document 1 discloses an example of an elevator control device. The control device predicts and calculates the temperature state of the elevator's components. Based on the predicted temperature state, the control device controls the operation of the elevator to prevent the components from becoming overloaded.

International Publication No. 2005/030627

However, the elevator control device described in Patent Document 1 estimates the temperature state of the inverter, which is a component of the device, using a transfer function model with the drive current as the input quantity. Therefore, in devices where there is thermal interference from heat generation or cooling from the surroundings in addition to self-heating, the prediction accuracy may decrease. On the other hand, using advanced models such as the finite element method to improve prediction accuracy may result in excessive computation time and processing power.

This disclosure relates to the solution of such problems. This disclosure provides an elevator temperature estimation system that can more easily improve the accuracy of temperature estimation even when there is thermal interference due to heat generation or cooling.

The elevator temperature estimation system according to this disclosure comprises an elevator control device, an ambient temperature sensor for measuring the ambient temperature of the elevator, and a calculation unit that performs temperature estimation calculations for preset temperature estimation points in the elevator based on a preset thermal model. The temperature estimation calculation performed by the calculation unit takes the ambient temperature input from the ambient temperature sensor, the parameters of the thermal model, and control information input from the control device that has a causal relationship with transient heat generation or cooling as input, and outputs a time series of temperature fluctuations at the temperature estimation points as the calculation result. The thermal model is an RC ladder and The thermal circuit model includes a heat flow source, the parameters of the thermal model are identified in advance by regression analysis based on control information corresponding to the elevator operating conditions and the temperature of the temperature estimation point and the ambient temperature measured in a test conducted in advance under those operating conditions, the RC ladder includes thermal resistance and heat capacity connected in one dimension or more and in one or more stages by a Foster network or Kauer network, and the heat flow source takes the control information as an argument and expresses the temporal change in the heat generation or cooling state of equipment affecting the temperature of the temperature estimation point by a change in the magnitude of the heat flow rate.

The elevator temperature estimation system described herein makes it easier to improve the accuracy of temperature estimation, even in cases of thermal interference due to heat generation or cooling.

This is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 1 is applied. This figure shows an example of a thermal model for the temperature estimation system according to Embodiment 1. This figure shows an example of a thermal model for the temperature estimation system according to Embodiment 1. This diagram shows an example of the operation of the temperature estimation system according to Embodiment 1. This is a hardware configuration diagram of the main part of the temperature estimation system according to Embodiment 1. This is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 2 is applied. This is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 3 is applied.

The embodiments for carrying out the subject matter of this disclosure will be described with reference to the attached drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are simplified or omitted as appropriate. However, the subject matter of this disclosure is not limited to the following embodiments, and any modification of any component of the embodiments or omission of any component of the embodiments is possible without departing from the spirit of this disclosure.

Embodiment 1.
Figure 1 is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 1 is applied.

Elevator 1 is applicable to buildings with multiple floors. A hoistway 2 for elevator 1 is provided in the building. The hoistway 2 is a long vertical space spanning multiple floors of the building. Elevator 1 comprises a hoisting machine 3, a main rope 4, a car 5, a counterweight 6, and a control device 7.

The hoisting machine 3 has a sheave. The hoisting machine 3 is a device that has the function of generating torque to rotate the sheave. The hoisting machine 3 includes, for example, a motor that generates torque.

The main rope 4 is wound around the sheave of the hoisting machine 3. The main rope 4 supports the load of the elevator car 5 by suspending the car 5 in the hoistway 2. The main rope 4 supports the load of the counterweight 6 by suspending the counterweight 6 in the hoistway 2. The main rope 4 may be, for example, a strand rope or a belt rope.

The elevator car 5 and the counterweight 6 travel in opposite directions within the hoistway 2 as the main rope 4 moves due to the rotation of the sheave of the hoisting machine 3. The elevator car 5 is a device that transports passengers and others between multiple floors by traveling vertically within the hoistway 2. The counterweight 6 is a device that balances the load on the main rope 4 on both sides of the sheave of the hoisting machine 3 with the elevator car 5. The elevator car 5 and the counterweight 6 travel vertically within the hoistway 2 by being guided, for example, by guide rails (not shown).

The control device 7 is a device that controls the operation of the elevator 1. The control device 7 controls, for example, the movement of the car 5 in response to a call. In this example, the movement of the car 5 from the departure floor to the destination floor is considered one movement of the car 5. The control device 7 also controls, for example, the opening and closing of doors provided on the car 5 of the elevator 1. The control device 7 holds control information related to the control of the elevator 1. The control information includes parameters that are causally related to either or both of the transient heat generation or cooling of each component constituting the elevator 1. These parameters may be continuous, discrete, or represent one of several options. The control information includes discontinuous values that represent the operating modes of the elevator 1, such as inverter drive command signals, fan drive command signals, door open command signals, and door close command signals. The control information also includes continuous values, such as motor current command values and car speed command values. The inverter is, for example, one that outputs drive current to the hoisting machine 3. Fans are used, for example, to blow air onto air-cooling equipment that makes up elevator 1.

In elevator 1, a temperature estimation system 8 is applied. The temperature estimation system 8 is a system that estimates the temperature of pre-set temperature estimation points in elevator 1 based on a pre-set thermal model. The temperature estimation points are points that correspond to the equipment constituting elevator 1 and are the subject of temperature estimation. The temperature estimation points may correspond to equipment such as the control device 7 or the hoisting machine 3, or to other equipment. The temperature estimation system 8 may be a system that estimates the temperature of multiple temperature estimation points. In this case, a separate thermal model may be set for each temperature estimation point. Multiple temperature estimation points may be set for each piece of equipment constituting elevator 1. For example, temperature estimation points may be set for some or all of the following: the magnet temperature and winding temperature of a permanent magnet motor, the bearing temperature, the chip temperature and case temperature of a power semiconductor, the electrolytic capacitor temperature, or the battery temperature.

The temperature estimation system 8 includes the control device 7 of the elevator 1. The temperature estimation system 8 comprises an ambient temperature sensor 9, a storage unit 10, and a calculation unit 11. Here, some or all of the functions of the storage unit 10 and the calculation unit 11 may be mounted on an external device of the elevator 1, or on equipment such as the control device 7 of the elevator 1.

The ambient temperature sensor 9 is a sensor that measures the ambient temperature of the elevator 1. The ambient temperature of the elevator 1 represents the temperature of the operating environment in which the equipment constituting the elevator 1 operates, such as the temperature around the equipment. Preferably, the ambient temperature sensor 9 is installed in a location where the influence of localized heat generation by the equipment constituting the elevator 1 is small. The ambient temperature sensor 9 is installed, for example, below the control device 7. The ambient temperature sensor 9 measures the ambient temperature at the location where it is installed. The temperature estimation system 8 may include a plurality of ambient temperature sensors 9 installed in different locations.

The memory unit 10 is the part equipped with the function of storing information. The memory unit 10 includes a parameter storage area 12 and a threshold storage area 13. The parameter storage area 12 is a storage area for storing parameters of the thermal model. The threshold storage area 13 is a storage area for storing temperature protection thresholds for the equipment of the elevator 1. The temperature protection threshold is a temperature threshold that is set in advance for each temperature estimation point in order to perform temperature protection for the equipment corresponding to that temperature estimation point.

The calculation unit 11 is the part equipped with the function of performing temperature estimation calculations at the temperature estimation point. The calculation unit 11 receives control information of the elevator 1 from the control device 7. The calculation unit 11 receives the ambient temperature measured by the ambient temperature sensor 9 from the ambient temperature sensor 9. The calculation unit 11 reads the parameters of the thermal model stored in the parameter storage area 12 of the storage unit 10. For example, as a temperature estimation calculation, the calculation unit 11 takes the control information of the elevator 1 and the parameters of the thermal model as input and calculates the temperature rise value at the temperature estimation point. The calculation unit 11 adds the calculated temperature rise value to the ambient temperature and outputs the time series of temperature fluctuations at the temperature estimation point as the calculation result.

The calculation unit 11 may perform temperature estimation calculations sequentially in real time, or it may perform them intermittently, such as after each trip of the elevator 1 or after a certain period of time has elapsed. The frequency of temperature estimation calculations by the calculation unit 11 may be set for each temperature estimation point according to the thermal time constant of the equipment corresponding to the temperature estimation point. The frequency of temperature estimation calculations by the calculation unit 11 may be, for example, every few seconds to every few hours.

The calculation unit 11 compares the estimated temperature calculated for the temperature estimation point with the temperature protection threshold corresponding to that temperature estimation point. When the estimated temperature of the temperature estimation point exceeds the temperature protection threshold corresponding to that temperature estimation point, the calculation unit 11 outputs an alert signal to the control device 7 that applies operational protection to the equipment corresponding to that temperature estimation point. Here, the alert signal may be a signal instructing an emergency stop of the car 5's movement, a signal instructing the car 5 to stop at the nearest floor, or simply a warning, depending on the severity of the situation caused by the malfunction of the equipment. When the alert signal is an instruction regarding the movement of the car 5, the control device 7 controls the operation of the elevator 1 according to the instruction.

Next, we will explain the configuration of the thermal model of the temperature estimation system 8 using Figure 2.
Figures 2A and 2B show examples of thermal models for the temperature estimation system according to Embodiment 1.

The thermal model is a thermal circuit model that includes an RC ladder 14 and a heat flow source 15. Figure 2A shows a thermal circuit model with a one-dimensional, three-stage Foster network connection. Figure 2B shows a thermal circuit model with a one-dimensional, three-stage Kauer network connection.

The RC ladder 14 is composed of thermal resistances 16 and thermal capacities 17 connected in a ladder-like manner. The RC ladder 14 is composed of a Foster network or a Kauer network. In the RC ladder 14, the thermal resistances 16 and thermal capacities 17 are connected in one dimension or more and in one or more stages. The resistance value of the thermal resistance 16 is expressed, for example, in units of K/W. The capacity value of the thermal capacities 17 is expressed, for example, in units of Ws/K. The heat flow rate of the heat source 15 is expressed, for example, in units of W.

In this example, the thermal circuit model is set independently for each temperature estimation point. When there are multiple temperature estimation points, it is not necessary for each temperature estimation point to share a thermal circuit model. Because the thermal circuit model is independent for each temperature estimation point, the individual thermal models become simpler, thereby reducing computation time. Furthermore, this tends to improve the accuracy of temperature estimation. While a sufficiently high estimation accuracy can often be obtained with a one-dimensional RC ladder 14 in each thermal model, the RC ladder 14 may be extended to two dimensions or more as needed.

In this example, the heat flow source 15 takes the control information of the elevator 1 as an argument and expresses the temporal change in the heat generation or cooling state of equipment affecting each temperature estimation point as a change in the magnitude of the heat flow rate. The heat flow source 15 expresses, for example, the temporal change in the heat generation or cooling state of other equipment, such as equipment surrounding the equipment corresponding to the temperature estimation point, as a change in the magnitude of the heat flow rate. The heat flow source 15 is composed of, for example, an arbitrary function such as that expressed by the following equation (1).

Here, t _n represents the time at the nth point in the time series. P(t _n ) represents the heat flow rate of the heat source 15 at time t _n . _{x i} (t _n ) represents the value of the i-th control information of elevator 1 at time t _n . _{A j} represents the j-th parameter among the time-independent constant parameters of the thermal model. _{T n} represents the temperature of the temperature estimation point at the nth point in the time series. Function f _k is the k-th function among the pre-set functions that constitute the model of the heat source 15. In this example, the model of the heat source 15 is represented by a sum of functions f _k . In this example, n, i, j, and k are natural numbers. The model of the heat source 15 may be a sum of three or fewer functions, or five or more functions, or a combination of multiple functions such as a product or composition.

Each function f _k is preferably a function that does not accumulate errors over time. Each function f _k is preferably a function whose absolute value does not diverge to infinity over time. Furthermore, each function f _k may be a function determined by constant parameters, such as function f ₁ in equation (1). Furthermore, each function f _k may include control information x ₁ as an argument, such as function f ₂ in equation (1). Furthermore, each function f _k may include multiple constant parameters, such as function f ₃ in equation (1). Furthermore, each function f _k may include one or both of a first-order lag element and a dead-time element, such as function f ₃ in equation (1). This allows the thermal model to more accurately represent the thermal behavior of the equipment in elevator 1, even when temperature fluctuations respond with a delay to changes in the state of elevator 1. Furthermore, each function f _k may take the temperature at a past time as an argument, such as function f ₄ in equation (1). As a result, even when the time constants differ between the heating and cooling processes, the thermal model can more accurately represent the thermal behavior of the equipment in elevator 1. Furthermore, since the control information of elevator 1 required to create the model of heat source 15 differs depending on the temperature estimation point, the model equation for heat source 15 will be different for each temperature estimation point.

Thus, the thermal model includes the resistance value of the thermal resistance 16 and the capacity value of the heat capacity 17 of the RC ladder 14, and the parameter _Aj of the heat flow source 15 as parameters of the thermal model. These parameters of the thermal model are identified in tests conducted in advance. In the tests, the elevator 1 is operated under multiple operating conditions. The parameters of the thermal model are identified for each temperature estimation point by a regression analysis method based on control information corresponding to these operating conditions, the temperature of the temperature estimation point measured during the operation, and the ambient temperature of the elevator 1. Here, the resistance value of the thermal resistance 16 and the capacity value of the heat capacity 17 of the RC ladder 14 as parameters of the model do not need to be directly related to the physical thermal resistance 16 and heat capacity 17 of any equipment in the elevator 1. Also, the model of the heat flow source 15 does not need to be directly related to the physical amount of heat generated in any equipment in the elevator 1.

Examples of calculation formulas sequentially calculated in the calculation unit 11, which uses a thermal model including the RC ladder 14 of a one-dimensional Foster network, are shown in the following equations (2) to (4).

Here, t _n represents the time at the nth point in the time series. P(t _n ) represents the heat flow rate of the heat source 15 at time t _n . R _m represents the resistance value of the thermal resistance 16 at the m-th stage of the RC ladder 14. C _m represents the capacity value of the heat capacity 17 at the m-th stage of the RC ladder 14. _{P C m} (t _n ) represents the heat flow rate through the heat capacity 17 at the m-th stage of the RC ladder 14 at time t _n . T(t _n ) represents the temperature rise value of the temperature estimation point at time t _n . The temperature rise value T(t _n ) of the temperature estimation point is expressed as shown in equation (4) by the sum of the temperature differences T _m (t _n ) at each stage of the RC ladder 14 over all stages. The temperature difference T _m at each stage of the RC ladder 14 is calculated using equation (2). Here, in the calculation of equation (2), the heat flow rate P _Cm (t _n-1 ) flowing to the heat capacity 17 at the previous time point t _n-1 is required. This heat flow rate P _Cm (t _n-1 ) is calculated in advance using equation (3) during the calculation of time point t _n-1 , which is before the calculation of time point _{t n} .

Next, we will explain an example of the operation of the temperature estimation system 8 using Figure 3.
Figure 3 is a flowchart showing an example of the operation of the temperature estimation system according to Embodiment 1.

In step S1, the ambient temperature sensor 9 measures the ambient temperature of the elevator 1. Then, the temperature estimation system 8 proceeds to step S2.

In step S2, the control device 7 outputs control information for the elevator 1 to the calculation unit 11. After that, the temperature estimation system 8 proceeds to step S3.

In step S3, the calculation unit 11 calculates the temperature rise value of the temperature estimation point using a thermal model based on the control information. After that, the temperature estimation system 8 proceeds to step S4.

In step S4, the calculation unit 11 adds the temperature rise value to the ambient temperature to estimate the temperature at the temperature estimation point. The calculation unit 11 outputs the estimated temperature as time-series data to, for example, the control device 7. After that, the temperature estimation system 8 proceeds to step S5.

In step S5, the calculation unit 11 determines whether the estimated temperature of the temperature estimation point exceeds the temperature protection threshold corresponding to that temperature estimation point. If it is determined that the temperature exceeds the temperature protection threshold, the temperature estimation system 8 proceeds to step S6. On the other hand, if it is not determined that the temperature exceeds the temperature protection threshold, the temperature estimation system 8 proceeds to step S1.

In step S6, the calculation unit 11 outputs an alert signal to the control device 7. The control device 7 controls the elevator 1 based on the alert signal. After that, the temperature estimation system 8 proceeds to step S1.

As described above, the temperature estimation system 8 according to Embodiment 1 comprises a control device 7 for the elevator 1, an ambient temperature sensor 9, and a calculation unit 11. The ambient temperature sensor 9 measures the ambient temperature of the elevator 1. The calculation unit 11 performs temperature estimation calculations for pre-set temperature estimation points in the elevator 1 based on a pre-set thermal model. In the temperature estimation calculation, the calculation unit 11 takes as input the ambient temperature input from the ambient temperature sensor 9, the parameters of the thermal model, and control information input from the control device 7 that has a causal relationship with transient heat generation or cooling. In the temperature estimation calculation, the calculation unit 11 outputs a time series of temperature fluctuations at the temperature estimation points as the calculation result. The thermal model is a thermal circuit model including an RC ladder 14 and a heat flow source 15. The parameters of the thermal model are identified in advance by a regression analysis method based on control information according to the operating conditions of the elevator 1 and the temperature of the temperature estimation points and the ambient temperature measured in a test conducted in advance under those operating conditions. The RC ladder 14 includes thermal resistance 16 and heat capacity 17 connected in one dimension or more and in one or more stages by a Foster network or Kauer network. The heat flow source 15 takes control information as an argument and expresses the temporal change in the heat generation or cooling state of the equipment that affects the temperature of the temperature estimation point by changing the magnitude of the heat flow.

With this configuration, the temperature estimation system 8 estimates the temperature at the temperature estimation point using a thermal model that includes an RC ladder 14 and a heat flow source 15. Temporal changes such as heat generation or cooling of surrounding equipment are represented by changes in the magnitude of the heat flow rate of the heat flow source 15. This allows for improved accuracy in temperature estimation at the temperature estimation point without the need for advanced models such as the finite element method. In particular, even when the structural function of the equipment changes over time, for example, when the on and off states of a cooling fan cooling the equipment corresponding to the temperature estimation point are switched over over time, the accuracy of temperature estimation at the temperature estimation point can be further improved by changes in heat flow rate via control information. Furthermore, since the thermal model is composed of an RC ladder 14, the required calculation time and computing power are not excessive. Therefore, the temperature at the temperature estimation point can be estimated quickly with simple calculations, enabling low-cost, real-time, continuous temperature estimation. The results of the temperature estimation can be used in various applications in the maintenance and management of elevator 1, such as estimating the lifespan from the operating temperature of each piece of equipment to plan maintenance and replacement, or using the operating temperature of each piece of equipment for quality control.

Furthermore, the thermal model includes at least one of the elements of a first-order lag and dead time in the heat flow source 15.

This configuration allows for improved prediction accuracy of temperature estimation at a temperature estimation point, even when the influence of heat generation or cooling from surrounding equipment is greater than the self-heating of the equipment corresponding to the temperature estimation point, and the temperature change lags behind changes in control information.

Furthermore, the heat source 15 of the thermal model includes an element that takes the temperature of the temperature estimation point as an argument.

This configuration allows for improved prediction accuracy of temperature estimation at temperature estimation points, even when the time constants for the heating and cooling processes differ.

Furthermore, the calculation unit 11 outputs an alert signal to the control device 7 to protect the operation of the equipment in the elevator 1 when the estimated temperature of the temperature estimation point exceeds a preset temperature protection threshold.

This configuration allows for advanced sensorless temperature protection of equipment corresponding to a temperature estimation point, without requiring sensors to directly measure the temperature at that point, by using the temperature estimation results of that point.

Next, we will explain an example of the hardware configuration of the temperature estimation system 8 using Figure 4.
Figure 4 is a hardware configuration diagram of the main components of the temperature estimation system according to Embodiment 1.

Each function of the temperature estimation system 8 can be implemented by a processing circuit. The processing circuit comprises at least one processor 100a and at least one memory 100b. The processing circuit may also include at least one dedicated hardware 200 together with the processor 100a and memory 100b, or as a substitute for them.

When the processing circuit includes a processor 100a and a memory 100b, each function of the temperature estimation system 8 is realized by software, firmware, or a combination of software and firmware. At least one of the software and firmware is written as a program. This program is stored in the memory 100b. The processor 100a realizes each function of the temperature estimation system 8 by reading and executing the program stored in the memory 100b.

The processor 100a is also called a CPU (Central Processing Unit), processing unit, arithmetic unit, microprocessor, microcomputer, or DSP. The memory 100b is composed of non-volatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM, or EEPROM.

If the processing circuit includes dedicated hardware 200, the processing circuit may be implemented as, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof.

Each function of the temperature estimation system 8 can be implemented by a separate processing circuit. Alternatively, each function of the temperature estimation system 8 can be implemented collectively by a processing circuit. Some functions of the temperature estimation system 8 may be implemented by dedicated hardware 200, while others are implemented by software or firmware. Thus, the processing circuit implements each function of the temperature estimation system 8 using dedicated hardware 200, software, firmware, or a combination thereof.

Embodiment 2.
In Embodiment 2, the differences from the example disclosed in Embodiment 1 will be explained in particular detail. For features not described in Embodiment 2, any of the features from the example disclosed in Embodiment 1 may be adopted.

Figure 5 is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 2 is applied.

The temperature estimation system 8 includes a generation unit 18. Here, some or all of the functions of the storage unit 10, the calculation unit 11, and the generation unit 18 may be mounted on an external device of the elevator 1, or on equipment such as the control device 7 of the elevator 1.

The generation unit 18 is a component equipped with the function of generating control information for each trip of the elevator car 5 of the elevator 1 before the trip is said to take place. Immediately before the start of the trip of the car 5, the generation unit 18 receives input of trip information from the control device 7, including the current floor and the destination floor of the car 5. Based on the trip information, the generation unit 18 generates control information for one trip, assuming that the trip is performed at one of several preset rated speeds, before the trip takes place. The generation unit 18 outputs the control information generated for each rated speed to the calculation unit 11.

The calculation unit 11 estimates the temperature at the temperature estimation point when the elevator car 5 travels at each rated speed, based on the control information generated by the generation unit 18 for each rated speed. The calculation unit 11 outputs to the control device 7 the fastest rated speed among the multiple rated speeds, provided that the estimated temperature does not exceed the temperature protection threshold corresponding to the temperature estimation point.

The control device 7 executes the movement of the elevator car 5 from the current floor to the target floor based on the rated speed input from the calculation unit 11.

With this configuration, the elevator car 5 travels based on a rated speed selected after comparing the estimated temperatures for multiple rated speeds with a temperature protection threshold. This allows the elevator 1 to continue providing service even if the equipment temperature becomes high, by reducing the travel speed within a range where the temperature protection of the equipment constituting the elevator 1 is not triggered.

Embodiment 3.
In Embodiment 3, the differences from the examples disclosed in Embodiment 1 or Embodiment 2 will be described in particular detail. For features not described in Embodiment 3, any of the features from the examples disclosed in Embodiment 1 or Embodiment 2 may be adopted.

Figure 6 is a diagram showing the configuration of an elevator to which the temperature estimation system according to Embodiment 3 is applied.

The temperature estimation system 8 comprises a gateway 19 and a data server 20.

The gateway 19 is a device that can connect to a public network, such as the Internet or a telephone network. The gateway 19 is installed, for example, in a building to which the elevator 1 is applied. The gateway 19 is connected, for example, to the processing unit 11.

The data server 20 is a server equipped with the function of accumulating and storing data about elevator 1. The data server 20 is an example of a storage unit. The data server 20 may be composed of, for example, one or more server devices. The data server 20 may be built on a cloud service. The data server 20 is located, for example, outside the building to which elevator 1 is applied. The data server 20 is connected to the gateway 19, for example, through a public telephone network.

The calculation unit 11 uploads the estimated temperature for each temperature estimation point to the data server 20 via the gateway 19. The data server 20 accumulates and stores the time-series history of the estimated temperatures for each temperature estimation point uploaded from the calculation unit 11 for long-term storage.

This configuration allows for the estimation of the lifespan of each device based on its operating temperature stored in the data server 20, enabling the planning of maintenance and replacement, as well as quality control of each device based on its operating temperature.

Furthermore, when the estimated temperature is used for purposes such as maintenance and replacement planning, the temperature estimation does not necessarily have to be performed in real time. In this case, some or all of the functions of the calculation unit 11 and the storage unit 10 may be installed in the data server 20. In this case, the calculation unit 11 acquires information such as control information for the elevator 1 and measured ambient temperature from the control device 7, for example, via the gateway 19.

The temperature estimation system described herein is applicable to elevators.

1. Elevator, 2. Hoistway, 3. Hoisting machine, 4. Main rope, 5. Cage, 6. Counterweight, 7. Control device, 8. Temperature estimation system, 9. Ambient temperature sensor, 10. Memory unit, 11. Calculation unit, 12. Parameter memory area, 13. Threshold memory area, 14. RC ladder, 15. Heat flow source, 16. Thermal resistance, 17. Heat capacity, 18. Generation unit, 19. Gateway, 20. Data server, 100a. Processor, 100b. Memory, 200. Dedicated hardware

Claims (6)

Elevator control device,
An ambient temperature sensor that measures the ambient temperature around the elevator,
A calculation unit that performs temperature estimation calculations for pre-set temperature estimation points in an elevator based on a pre-set thermal model,
Equipped with,
The temperature estimation calculation performed by the calculation unit takes the ambient temperature input from the ambient temperature sensor, the parameters of the thermal model, and control information input from the control device that has a causal relationship with transient heat generation or cooling as input, and outputs a time series of temperature fluctuations at the temperature estimation point as the calculation result.
The aforementioned thermal model is a thermal circuit model that includes an RC ladder and a heat flow source.
The parameters of the thermal model are identified in advance by a regression analysis method based on the control information corresponding to the elevator's operating conditions, and the temperature of the temperature estimation point and the ambient temperature measured in a test conducted in advance under those operating conditions.
The RC ladder includes thermal resistance and thermal capacitance connected in one or more dimensions and one or more stages by a Foster network or a Kauer network.
The heat source, using the control information as an argument, expresses the temporal change in the heat generation or cooling state of the equipment affecting the temperature at the temperature estimation point by a change in the magnitude of the heat flow rate.
Elevator temperature estimation system. The thermal model includes at least one of the elements of a first-order lag and dead time in the heat source.
The elevator temperature estimation system according to claim 1. The heat source in the thermal model includes an element that takes temperature as an argument.
The elevator temperature estimation system according to claim 1 or claim 2. The calculation unit outputs an alert signal to the control device to protect the operation of the elevator equipment when the estimated temperature at the temperature estimation point exceeds a preset temperature protection threshold for the equipment.
The elevator temperature estimation system according to claim 1 or claim 2 . For each trip of the elevator, the system includes a generation unit that generates control information before the trip, based on information including the current floor and destination floor of the elevator car input from the control device, for each trip to be performed at a preset number of rated speeds.
The calculation unit estimates the temperature of the temperature estimation point when the run is performed at each of the multiple rated speeds input from the generation unit, based on the control information for each of the multiple rated speeds, and outputs to the control device the fastest rated speed among the multiple rated speeds in which the estimated temperature does not exceed the temperature protection threshold.
The control device executes the run based on the rated speed input from the calculation unit.
The elevator temperature estimation system according to claim 4. The elevator temperature estimation system according to claim 1 or claim 2 , further comprising a storage unit that stores and stores the temperature of the temperature estimation point estimated by the calculation unit.