Abstract: An electric multi-mode drive system (400), a method for operating the same, a vehicle (110) and a track (401). The system is arranged for operating at one part (402) of the track (401), at a station (410; 411), an electric Linear Doubly Fed Motor, LDFM, (310) for launching the vehicle (110), and for operating at another part (403) of the track (401), between stations (410; 411), a further electric motor (320; 330; 340; 350), not an LDFM, arranged for at least one of accelerating, coasting and restarting movement of the vehicle (110) after launching. Electric power for operating the further electric motor (320; 330; 340; 350), is provided by an on-board rechargeable electrical energy storage device. With the LDFM (310), sufficient power is generated for accelerating the vehicle (110), and recharging the on-board electrical energy storage device during standstill, braking and/or launching.

Abstract: An electric multi-mode drive system (400), a method for operating the same, a vehicle (110) and a track (401). The system is arranged for operating at one part (402) of the track (401), at a station (410; 411), an electric Linear Doubly Fed Motor, LDFM, (310) for launching the vehicle (110), and for operating at another part (403) of the track (401), between stations (410; 411), a further electric motor (320; 330; 340; 350), not an LDFM, arranged for at least one of accelerating, coasting and restarting movement of the vehicle (110) after launching. Electric power for operating the further electric motor (320; 330; 340; 350), is provided by an on-board rechargeable electrical energy storage device. With the LDFM (310), sufficient power is generated for accelerating the vehicle (110), and recharging the on-board electrical energy storage device during standstill, braking and/or launching.

Abstract: A method of controlling an electric motor (motor) includes providing a processor having an associated memory storing a stator resistance (Rs) estimation (RSE) algorithm that is programmed to implement the RSE algorithm to execute steps including injecting a current waveform at an arbitrary frame of reference into the stator using a field-oriented-control (FOC) motor controller including an Id controller and an Iq controller, and measuring current and voltage values from the motor responsive to the injecting. The measured current and voltage values are then transformed into transformed current and voltage values in a d/q coordinate system. The transformed current and voltage values are low pass filtered to generate filtered d/q current and voltage values, and a value for Rs is estimated from the filtered d/q current and voltage values. The arbitrary frame of reference can be a time-varying frame of reference.

Abstract: A method of controlling an electric motor (motor) includes providing a processor having an associated memory storing a stator resistance (Rs) estimation (RSE) algorithm that is programmed to implement the RSE algorithm to execute steps including injecting a current waveform at an arbitrary frame of reference into the stator using a field-oriented-control (FOC) motor controller including an Id controller and an Iq controller, and measuring current and voltage values from the motor responsive to the injecting. The measured current and voltage values are then transformed into transformed current and voltage values in a d/q coordinate system. The transformed current and voltage values are low pass filtered to generate filtered d/q current and voltage values, and a value for Rs is estimated from the filtered d/q current and voltage values. The arbitrary frame of reference can be a time-varying frame of reference.

Abstract: The fluid flow of a fluid displacement device (100) provided with an electric motor (120) may be set on the basis of a power and control unit (90). Thereto, a power circuit generally comprising an inverter (30), such as a frequency inverter, drives the electric motor (110), particularly with a driving voltage (D1). Voltage and current (A1, A2) in the electric motor (110) are sensed sensorless. Torque and rotation speed of the electric motor (110) are derived from said sensed voltage and current (A1, A2). A fluid flow of the fluid displacement device (110) is estimated in an estimator (15) based on said torque and rotation speed of the electric motor (120) and at least some fluid displacement device characteristics stored in a memory.

Abstract: A lighting system for operation with a dimmer circuit comprising a triac connected to a load. The load comprises a driver circuit for supplying current to a light source comprising one or more LEDs, the current being determined at least in part by an adjusted setpoint value. The system further comprises a setpoint filter circuit for obtaining a dimmer setpoint value determined at least in part by a setting of the dimmer circuit, and for generating an adjusted setpoint value. The sensitivity of the adjusted setpoint value to changes in the dimmer setpoint value is low at low values of the dimmer setpoint value.

Abstract: The invention relates to a dimmer triggering circuit (12) for triggering a dimmer in an alternating current network. The dimmer has a voltage-level detector (15), and a bipolar current source circuit (18). The voltage-level detector (15) detects whether an absolute value of an input voltage of the dimmer triggering circuit is below a threshold value. The bipolar current source circuit (18) provides a current if the voltage detected by the voltage-level detector (15) is below the threshold value. If the voltage detected is not below the threshold value, the bipolar current source circuit is deactivated. The dimmer triggering circuit (12), in operation, dissipates an average power less than 100 mW.

Abstract: A lighting system for operation with a dimmer circuit comprising a triac connected to a load. The load comprises a driver circuit for supplying current to a light source comprising one or more LEDs, the current being determined at least in part by an adjusted setpoint value. The system further comprises a setpoint filter circuit for obtaining a dimmer setpoint value determined at least in part by a setting of the dimmer circuit, and for generating an adjusted setpoint value. The sensitivity of the adjusted setpoint value to changes in the dimmer setpoint value is low at low values of the dimmer setpoint value.

Abstract: An amplifier circuit (11) for amplifying electric signals, comprising controllable switching means (2) for generating a block wave signal whose amplitude varies between first and second supply voltage values during operation, filter means (9) for filtering the block wave signal so as to produce an output signal (10). The filter means (9) comprise a self-inductance (16) and a capacitance (17). The amplifier circuit (11) furthermore comprises modulating means (3) for pulse width modulation of the block wave signal by driving the switching means (2) in response to an input signal (16) to be amplified, and correction means (12) for providing from a reference value (Uref) derived from the input signal and an output signal value proportional to the output signal (10) a correction signal for controlling the modulating means (3).

Abstract: Disclosed is a method for determining the contents of a gas bottle, in particular a liquid gas bottle, comprising the following steps: First of all, the gas bottle is excited by applying a signal to a loudspeaker mounted on said gas bottle. The signal from a microphone mounted on the gas bottle is compared in phase with the signal used for excitation, with the frequency of the signal applied to said loudspeaker being altered continuously, until a resonant frequency is established. This resonant frequency is converted into a filling level of the gas bottle according to a previously determined relationship between the resonant frequency and the filling level. Furthermore, an apparatus is disclosed with which the above-mentioned method may be put into practice.