FI114978B - Elevator has rectifier and inverter separated from each other and inverter integrated with alternating current elevator motor - Google Patents

Abstract

The elevator has a drive apparatus having a frequency converter consisting of a rectifier (RECT1), inverter (INV1) and a direct voltage circuit in between the rectifier and the inverter separated from each other. The inverter is integrated with an alternating current (AC) elevator motor (M1). An independent claim is also included for method of controlling elevator.

Description

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THE LIFT AND ITS CONTROL

The present invention relates to an elevator, wherein the elevator motor is an AC motor controlled by a frequency converter, wherein the frequency converter has 5 rectifiers connected to the AC mains and an inverter (motor drive) supplying the motor and a DC circuit between them. The invention also relates to a method for controlling an elevator during maintenance / repair.

Today, elevator drives are generally either general-purpose or special-purpose drives developed by elevator manufacturers. Both solutions are problematic for elevator manufacturers, since general-purpose drives are not optimized for traction, and because elevator manufacturers have relatively low usage rates for economical manufacturing. General use has been a good solution mainly for other applications like pumps etc. Developing control software has been relatively easy as almost 15 short-circuit motors have always been used as motor and control has been the same in most applications. Recently, permanent magnet synchronous (PMSM) machines have become popular and performance requirements for motor and motion control have increased. It has become increasingly expensive to develop general - purpose motor drives that could control all kinds of engines. PMSM control also tends to increase costs because open-loop motor control is difficult in PMSM compared to a short-circuit motor. Due to lower output frequencies, the use of PMSM requires larger power semiconductors such as IGBTs (Insulated Gate Bipolar Transistor).

In non-machine-type elevators, the electrical control of the motor drive: 25 units are typically located on the roof of the shaft. · The engine is repaired and electricized from the roof of the elevator car. Access to the roof of the elevator car requires that the elevator car be first raised to a suitable level. Reaching the roof of the elevator car is relatively easy in counterweight lifts because an empty elevator car rises by itself without electrical power.

30 In an unweighted elevator, the elevator car does not automatically rise upwards I *, for example, in the event of a failure in the motor drive of the elevator or its control unit, but must be provided with a separate power supply for maintenance and repairs. i This can be arranged so that there is a space between the drive and the motor; an additional switch arrangement, either to the elevator shaft or to the installation panel (Main tenance access panel = MAP), to which a battery is then connected to move the elevator during maintenance / repair. This requires an additional switch and the necessary connections. Connecting is time consuming and often requires specialized tools. In addition, moving the elevator car in this manner consumes a relatively large amount of energy 2 114978 (typically 100 ... 300 kJ, which is the full capacity of a typical 12 V / 8Ah battery). Maintenance and repairs are therefore difficult, and especially more difficult, than in counterbalanced lifts.

Thus, the main problem with an unweighted elevator is that moving the elevator car during maintenance / repair requires additional coupling. Another problem is that the relatively simple connection to the motor does not help if the power output of the motor drive (inverter) is damaged. In addition, there must be a relatively expensive and shielded cable between the cabling motor and the MAP, since PWM control, especially on long cables, easily generates 10 RF interference.

The object of the present invention is to overcome the drawbacks of the prior art and to provide a novel elevator drive architecture based on a customer-specific solution, which not only implies changes to the control software but also a completely new enclosure concept specifically adapted to a machine roomless elevator.

In the elevator drive according to the invention, the motor drive (inverter) is integrated with the elevator motor. Only the rectifier and the elevator drive control unit are located in the control / power unit in the elevator shaft.

In the inverter drive according to the invention 20 - the inverter is a "black box" with no user interface - the drive interface is simple motion control - the inverter is thermally optimized for traction drive operation:,; - the inverter is very compact as a brick · .. - the inverter has DC- inlet • '; 25 - dimensions so small that flexible placement is possible ..: The invention also provides the following advantages: · ·. - motor operation is very simple and reliable • ·' .f - motor-to-motor cabling is minimal '' - motor drive can utilize motor mechanics and cooling capacity • »j - DC battery can be used as back-up power source:.: - motor drive can be tested with motor and operating parameters can be set at engine factory: - motor drive manufacture is advantageous when manufactures 35 large quantities of standard products articles>

In addition, maintenance becomes easier as the number of components decreases, especially since component connections are a major cause of failure. In addition, the integrated system operates more reliably than a solution implemented with separate components, and the same rectifier can be used for multiple elevator drives.

The features of the elevator drive according to the invention and the method for controlling the elevator drive are described in detail in the appended claims.

The invention will now be described in more detail by way of example with reference to the accompanying drawing, in which Figure 1 illustrates the elevator of the invention in simplified form, and Figure 2 shows the elevator drive according to the invention.

Figure 1 illustrates a non-engine room elevator with an elevator motor M1, for example a disk-like permanent magnet AC electric motor, and its control I located in the elevator shaft SHAFT 1. The CAR1 elevator car is counterweight. The moving ropes and other transmission equipment are not shown.

The control system for the elevator motor i / 11 includes an elevator power unit 15 EPU1 with a rectifier RECT1 and a control unit LCE1, a motor drive (inverter) INV1 and a mounting panel MAPI on the elevator shaft wall. The EPU1 power unit and the MAPI installation panel as well as the MAPI installation unit and the INV1 motor drive are connected via cables CABLE1 and CABLE2.

The power unit EPU1 is located on the wall of the SHAFT1 shaft. The Moot-20 market drive INV1 is integrated with the M1 motor. In this way, the cables CABLE1 and CABLE2, as well as the MAPI installation panel, form the direct current circuit of the drive.

During maintenance and repairs, the elevator car is raised by feeding MAPI (dc circuit) from the battery BATT1, for example 48 V, '; 25 5 ... 10 Ah) DC voltage.

Fig. 2 is a block diagram illustrating the invention,. elevator operation, in which the operation is divided into two parts, the power unit EPU1 'and the inverter INV1, and in which the tachometer on the motor M axis provides a' speed / position feedback '. The power unit provides inverter control, and the status of the 30 inverters is controlled to EPU1.

It will be apparent to one skilled in the art that various embodiments of the invention; . The dots are not limited to the example above, but can be exchanged; ; within the scope of the following claims.

Claims (7)

An elevator, provided with a lift basket (CAR1) and a drive machinery which drives the elevator basket, which drive unit is provided with an AC lift motor (M1) and a frequency converter comprising a rectifier (RECTI) and an inverter (INV1) and between them a DC circuit, characterized in that the rectifier (RECTI) and the inverter (INV1) are separate, and that the inverter (INV1) is integrated in the motor (M1). Elevator according to claim 1, wherein the elevator basket is located in the elevator shaft (SHAFT1) and in which elevator a connection part (MAPI) is placed in the elevator shaft or at the plane of the plane, characterized in that the rectifier and the inverter via the connection part are joined by cables (CABLE). 1, CABLE2). Elevator according to claim 1, wherein the elevator has a connection part (MAPI) located in the elevator shaft or on the plane of the aircraft, characterized in that the elevator has a backup power unit (BATT1) which can be connected to the DC intermediate link, preferably in the connection part 15 (MAPI). Elevator according to claim 1, characterized in that the rectifier is located in the control part of the elevator operation (EPU1) and the inverter has no user interface. Elevator according to claim 1, characterized in that the control part (EPU1) of the elevator operation and the connection part (MAPI) are arranged in the same unit on the plane. Elevator according to claim 1, characterized in that the elevator is machine-roomless and. counterweight. 7. Method of controlling an elevator, provided with a lift basket (CAR1) and one in; 1 'lift shaft or connecting plane (MAPI) and a drive machinery 1 · - ·' which drives the lift basket, which drive is provided with an alternating current motor (Ml) »· 25 and a frequency converter comprising a rectifier (RECTI) and an inverter (INV1). ) and • / between them a direct current circuit, in which method the elevator at e.g. maintenance work and:: repair work is controlled by another voltage source connected to the elevator, preferably a direct voltage source, characterized in that the rectifier (RECT1) and inverter (INV1) are:. separate, and that the inverter is integrated into the motor (M1), and that the second voltage is measured at the DC voltage intermediate via the connection part (MAPI).