Elevator temperature control and energy-saving system and control method thereof

Abstract

The present invention discloses a temperature control and energy-saving system, comprising: a first power factor detection device electrically connected to an input port of a local power grid; electrical equipment electrically connected to the local power grid; and an elevator system electrically connected to the local power grid, wherein the elevator system comprises an elevator reactive power compensation unit, and the elevator reactive power compensation unit compensates for the reactive power of the local power grid so that the elevator itself generates heat.

Description

Technical Field

[0001] The present invention relates to the field of elevators, and in particular to an elevator temperature control and energy-saving system. Background Art

[0002] When in standby mode, elevators consume little energy and generate very little heat in the machine room. To ensure continuous and safe elevator operation during winter in northern China, the machine room must be equipped with defrosting heating equipment, heaters, or air conditioners. This heating system heats the entire machine room; for machine-room-less elevators, the entire elevator shaft must be heated. This heating method is extremely inefficient and wastes a significant amount of energy. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an efficient elevator temperature control and energy-saving system and a control method thereof.

[0004] In order to solve the above technical problems, the present invention discloses an elevator temperature control and energy-saving system, comprising:

[0005] a first power factor detection device electrically connected to an input port of a local power grid;

[0006] Electrical equipment connected to the local power grid;

[0007] An elevator system electrically connected to a local power grid comprises an elevator reactive power compensation unit, which compensates for the reactive power of the local power grid so that the elevator generates heat.

[0008] Preferably, the elevator reactive power compensation unit includes an elevator inverter device, which compensates for the reactive power of the local power grid by adjusting the current and / or voltage phase angle input to or output from the elevator.

[0009] Preferably, it further includes a second reactive power compensation device and a second power factor detection device; the second power factor detection device is electrically connected to the input port of the second reactive power compensation device; the elevator system compensates for the reactive power of the local power grid based on data detected by the second power factor detection device.

[0010] Preferably, the elevator system and the electrical equipment are at least one each.

[0011] Preferably, the first power factor detection device or the second power factor detection device is a current detection device or a voltage detection device.

[0012] Preferably, the first power factor detection device is a functional block in the elevator equipment.

[0013] Preferably, the first power factor detection device and the second power factor detection device are a functional block in the elevator equipment.

[0014] Preferably, the first power factor detection device and the second power factor detection device are a functional block in the second reactive power compensation device.

[0015] The present invention also discloses a control method for an elevator temperature control and energy-saving system, comprising the following steps:

[0016] When the ambient temperature of the elevator system is lower than the preset minimum temperature, the elevator analyzes the detection data of the first power factor detection device or the second power factor detection device, compensates for the reactive power of the local power grid where the elevator is located, and at the same time increases the temperature of the elevator system itself and its surroundings.

[0017] Preferably, the preset minimum temperature is 0°C.

[0018] Preferably, when the reactive power compensation fails to reach a preset control target, the elevator device continues to perform reactive power output compensation until the temperature of the elevator system itself is controlled at a maximum preset temperature.

[0019] Preferably, the maximum preset temperature is 50°C.

[0020] Preferably, when the reactive power compensation reaches the control target, the elevator will reduce the output of reactive compensation and keep the temperature of the elevator system itself and the surrounding area near a specific temperature, preferably between 5°C and 40°C.

[0021] Preferably, when the reactive power compensation reaches the control target and the elevator temperature itself is still lower than the preset minimum temperature, the elevator can use hysteresis control of under-compensation and over-compensation of the power factor to make the elevator inverter continue to generate heat, so that the elevator itself heats up and maintains the temperature near a specific temperature.

[0022] Preferably, when the reactive power compensation reaches the control target and the elevator's own temperature is still lower than the preset minimum temperature, the elevator can continuously output current to drive the elevator traction machine through the inverter device, causing the traction machine itself to heat up, causing the elevator inverter device itself to heat up, and maintaining the temperature near a specific temperature.

[0023] Preferably, when the compensation of reactive power reaches the control target and the temperature of the elevator itself is still lower than the preset minimum temperature, the elevator can increase the output current of a specific phase according to the current data detected by the second power factor detection device, so that the current of the specific phase detected by the second power factor detection device gradually decreases, causing the elevator inverter device itself to heat up and maintain the temperature near the specific temperature.

[0024] This solution allows elevator equipment to raise the ambient temperature in low-temperature environments through self-heating, eliminating the need for additional heating equipment or reducing its output. Furthermore, the elevator equipment's compensation for reactive power in the local power grid contributes to energy conservation and consumption reduction. Maintaining the operating temperature of elevator power components within a certain range over the long term helps extend the thermal cycle life of these components. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural diagram of embodiment 1 of the present invention.

[0026] Figure 2 It is a structural diagram of embodiment 2 of the present invention. DETAILED DESCRIPTION

[0027] Embodiment 1: The present invention includes an elevator temperature control and energy-saving system, comprising: a first power factor detection device electrically connected to an input port of a local power grid; electrical equipment electrically connected to the local power grid; and an elevator system electrically connected to the local power grid. The elevator system includes an elevator reactive power compensation unit, which compensates for the reactive power of the local power grid to generate heat for the elevator. The elevator reactive power compensation unit includes an elevator inverter, which compensates for the reactive power of the local power grid by adjusting the current and / or voltage phase angles input to or output from the elevator.

[0028] When the ambient temperature of the elevator equipment falls below a specific temperature, preferably 5°C, the elevator analyzes the detection data from the first power factor detection device and compensates for the reactive power of the local power grid where the elevator is located, while simultaneously increasing the ambient temperature of the elevator equipment. If the reactive power compensation fails to meet the control target, the elevator equipment continues to output reactive power compensation until the ambient temperature of the elevator equipment is controlled below the temperature at which the elevator equipment can safely operate, preferably 40°C. If the reactive power compensation meets the control target, but the elevator's temperature remains below 5°C, the elevator uses hysteresis control, combining under- and over-compensation of the power factor, to cause the elevator's inverter to continuously generate heat and maintain the elevator's self-generated temperature near a specific temperature, preferably 5°C. The elevator can also employ a method in which the inverter continuously outputs current to drive the elevator's traction motor, causing the motor to generate heat, thereby increasing the temperature of the elevator's inverter and maintaining it near the specific temperature. The technical effect of the present invention is that using the elevator equipment's own heat instead of external heating equipment can improve heating efficiency. Specifically, less energy is required to heat the local space within the elevator control cabinet.

[0029] It is generally estimated that the self-heating capacity of an elevator can be several kilowatts, which is enough to replace external heating equipment.

[0030] Most of the elevator's losses come from the elevator's frequency conversion circuit, including conduction loss and switching loss of semiconductor devices. These losses are generally dissipated to the surrounding area of ​​the elevator equipment in the form of heat.

[0031] By using the elevator frequency conversion control component to compensate for the reactive power of the local power grid, it is possible to achieve the goal of saving energy and reducing consumption for the local power grid, and also to use the loss of the elevator frequency conversion control component to increase the temperature of the elevator equipment itself and the surrounding environment.

[0032] When the elevator meets the reactive power compensation target for the local power grid, it can also take maintaining the self-generated and surrounding temperatures of the elevator equipment as the control target, and adopt a swing control strategy near the reactive power compensation target to make the elevator inverter continue to generate heat.

[0033] The maximum reactive power compensation output of the elevator to the local grid is to keep the ambient temperature of the elevator equipment below the maximum operating temperature allowed. The preferred maximum preset temperature is between 40 and 50°C.

[0034] Controlling the temperature of the elevator equipment itself and / or its surroundings, and maintaining the temperature of the elevator inverter components within a specific range, is conducive to the normal operation of the elevator in a low-temperature environment; and keeping the elevator inverter within a certain temperature range for a long time is also conducive to improving the power cycle life of the elevator power devices.

[0035] Example 2 The difference between the solution of Example 2 and Example 1 is that Example 2 also includes a second reactive power compensation device and a second power factor detection device; the second power factor detection device is electrically connected to the input port of the second reactive power compensation device; the elevator system compensates for the reactive power of the local power grid based on the data detected by the second power factor detection device.

[0036] When the temperature around the elevator equipment falls below a specific temperature, preferably 5°C, the elevator analyzes the detection data from the second power factor detection device, compensates for the reactive power of the local power grid where the elevator is located, and simultaneously increases the temperature around the equipment itself. If the compensation current of the reactive power compensation device is large, the elevator equipment continues to output reactive power compensation until the temperature around the elevator equipment is controlled below the temperature at which the elevator equipment can safely operate, preferably 40°C. If the compensation current of the reactive power compensation device is small, the elevator adopts a swing control strategy around the reactive power compensation target, causing the elevator inverter to continuously generate heat and maintain the temperature around the elevator near a specific temperature, preferably 5°C.

Claims

1. An elevator temperature control and energy saving system, characterized in that: include: a first power factor detection device electrically connected to an input port of a local power grid; Electrical equipment connected to the local power grid; An elevator system electrically connected to a local power grid, the elevator system including an elevator reactive power compensation unit, the elevator reactive power compensation unit compensating for reactive power of the local power grid while generating heat in the elevator itself; the elevator reactive power compensation unit including an elevator inverter device; When the reactive power compensation reaches the control target, the elevator will reduce the reactive power compensation output and keep the elevator system and its surrounding temperature between 5℃ and 40℃; When the reactive power compensation reaches the control target and the elevator temperature is still below 5°C, the elevator can use the hysteresis control of under-compensation and over-compensation of the power factor to make the elevator inverter continue to generate heat, so that the elevator itself heats up and maintains the temperature at 5°C.

2. The elevator temperature control and energy saving system according to claim 1, characterized in that: include: The elevator reactive power compensation unit includes an elevator inverter device, which compensates for the reactive power of the local power grid by adjusting the current and / or voltage phase angle input to or output from the elevator.

3. The elevator temperature control and energy saving system according to claim 1, characterized in that: It also includes a second reactive power compensation device and a second power factor detection device; the second power factor detection device is electrically connected to the input port of the second reactive power compensation device; the elevator system compensates for the reactive power of the local power grid based on data detected by the second power factor detection device.

4. The elevator temperature control and energy saving system according to claim 1, characterized in that: The number of the elevator system and the number of the electrical equipment are at least one.

5. The elevator temperature control and energy saving system according to claim 3, characterized in that: The first power factor detection device or the second power factor detection device is a current detection device or a voltage detection device.

6. The elevator temperature control and energy saving system according to claim 3, characterized in that: The first power factor detection device is a functional block in the elevator equipment.

7. The elevator temperature control and energy saving system according to claim 3, characterized in that: The first power factor detection device and the second power factor detection device are a functional block in the elevator equipment.

8. The elevator temperature control and energy saving system according to claim 3, characterized in that: The first power factor detection device and the second power factor detection device are a functional block in the second reactive power compensation device.

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