Abstract:
A power supply appliance of a transport system is provided. The appliance includes a power rectifier of the motor, an AC voltage circuit, a control voltage circuit, a power supply circuit of the safety devices, an AC/DC transformer fitted between the AC voltage circuit and the control voltage circuit to supply power from the AC voltage circuit to the control voltage circuit, and a power shaping circuit.
Abstract:
A system and a method for monitoring a safety circuit are presented. The system includes a control appliance and the safety circuit comprises at least one serial circuit of two or more switches. The arrangement system also includes a way of measuring the status of at least one switch, as well as a way of conveying the status information of the switch to the control appliance. The method includes measuring the status information of at least one switch and sending the measured status information to the control appliance.
Abstract:
A DC/DC bridge having a power stage provided with controllable semiconductor switches controls a direct currently load, and comprises two bridge sections, one of which bridge sections conducts direct currently while the other bridge section is controlled via pulse width modulation to regulate the current magnitude. Two of three bridge arms of the DC/DC bridge are connected in parallel and semiconductor switches in the parallel-connected bridge arms are controlled via pulse width modulation to form a pulse width modulation controlled bridge section.
Abstract translation:具有设置有可控半导体开关的功率级的DC / DC桥控制直接的当前负载,并且包括两个桥接部分,其中一个桥接部分目前正在导通,而另一个桥接部分通过脉冲宽度调制被控制以调节电流幅度 。 DC / DC电桥的三个桥臂中的两个并联连接,通过脉宽调制来控制并联桥臂中的半导体开关,形成脉宽调制控制桥段。
Abstract:
The power control of a transport system comprises an electric motor for moving the transport appliance as well as a power supply appliance of the motor, which comprises an intermediate circuit. The power supply appliance of the motor is fitted between the power source and the electric motor. The transport system further comprises a network rectifier, which is fitted between the power source and the intermediate circuit of the power supply appliance of the motor for supplying braking power returning from the motor of the transport appliance to the power source.
Abstract:
Method for controlling a permanent magnet synchronous motor, wherein an equivalent circuit describing the characteristics of the permanent magnet synchronous motor is formed, and via calculations based on. the equivalent circuit, a vectorial representation of the control quantities is produced, in which the horizontal axis of the co-ordinate system used represents the magnetisation, the vertical axis represents the torque and the vectors used are stator voltage (Us), supply voltage (e) and current (I), which is at a distance of 90° from the horizontal axis. In the vectorial representation, a correction vector (dU) is formed via inference based on the equivalent circuit and the correction vector is summed with the electromotive force, giving the stator voltage (Us) as a result.
Abstract:
A conveying system, includes control devices for controlling the operation of the conveying system. The conveying system also includes a central control. The central control is arranged to select from a plurality of the different operating modes of the conveying system the operating mode to be used at any given time. The central control is connected to the control devices with a communications channel for indicating the operating mode selected to the control devices.
Abstract:
The invention relates to a frequency converter, which is fitted to supply power between a polyphase alternating electricity source and an electric machine. The frequency converter comprises a network rectifier connected to the alternating electricity source and an inverter connected to the electric machine. The power supply is implemented in the network rectifier and in the inverter with solid-state change-over switches, which change-over switches comprise an antiparallel-connected diode fitted in parallel with the controllable switch. The network rectifier and the inverter are connected to each other with an intermediate circuit, which intermediate circuit is implemented without a passive energy storage.
Abstract:
The invention relates to an elevator system and a method for reducing total power in an elevator system. According to the invention, the elevator system comprises at least one elevator without counterweight for moving people and/or goods, which elevator without counterweight comprises a power converter unit, an elevator motor, a traction sheave, a set of hoisting ropes and an elevator car, and which elevator system comprises means for storing mechanical energy and discharging an energy storage.
Abstract:
The present invention describes a method and an apparatus for storing electric energy needed in an elevator system into a supercapacitor. Furthermore, the invention can be used as a source of reserve power in emergency situations, such as power failures. The supercapacitor is connected together with three switching branches to a rectified signal of the power supply of the motor. By closing and opening the switches, the supercapacitor can be charged when the motor load is small. When the motor load is large or when the power supply fails, the electric energy contained in the supercapacitor can be discharged for use by the motor. In an emergency, the motor drives the elevator at a speed lower than normal, and therefore a supply voltage lower than normal is sufficient. Also, energy obtained from braking of the elevator can be stored in the supercapacitor, which has a storage capacity of considerable magnitude as compared to an ordinary capacitor. By applying the invention, the energy consumption of the elevator can be reduced because the waste energy obtained from the power supply can be stored and utilized when more energy is needed.
Abstract:
A method and an apparatus for adjustment of the rotor angle of an elevator motor (M), in which method: the rotor angle of the elevator motor is measured, the rotor angle is adjusted by using the measured rotor angle value as feedback data, and the rotor angle is measured by means of a pulse emitter (PE) or tachometer connected to the elevator motor. In the method, a disturbance signal (u) is fed into the rotor angle feedback data to produce a change (disturbance) in the rotor angle, the change (disturbance) is compared to the disturbance signal (u), and, on the basis of the comparison, a control signal is generated to adjust the rotor angle.