Abstract: The invention concerns a method for generating an alarm signal in a motor which comprises a rotor (50) whose actual rotation speed during operation lies in a normal zone (nSoll, TSoll), can deviate from that normal zone in the event of a fault, and is to be monitored for a fault state, comprising the following steps: At least one alarm switch-on rotation speed (naOn, TAOn) and at least one alarm switch-off rotation speed (nAOff, TAOff) are defined, of which the latter is located closer to the normal zone than the former, an associated pair of alarm switch-on rotation speed and alarm switch-off rotation speed defining between them a hysteresis zone. When the rotation speed to be monitored arrives, coming from the hysteresis zone, at the alarm switch-on rotation speed, an alarm switch-on criterion (Flag DIR=0) is generated. The duration of this alarm switch-on criterion is monitored. When this duration reaches a predetermined value (tdOn), an alarm signal (ALARM) is activated (FIG. 13: S186, S194).

Abstract: In a method for commutating an electronically commutated motor, a predictive calculation is made of a first time span that the rotor will need in order to pass through a specified rotation angle that lies between a first rotational position (∂0) and a later second rotational position (∂1) at which a switching operation is to be effected in the motor. Upon actual passage through the first rotational position, a reference time is identified and stored. The time difference between the present time and the stored reference time is then monitored repeatedly and compared to the first time span; and when a specified relationship exists between the time difference and the first time span, the switching operation is performed.

Abstract: An arrangement having an electric motor (10) has a microcontroller (12) for influencing at least one motor function and a nonvolatile storage element (14) for storing at least one variable as a definition for that motor function. The arrangement also has an interface (13a) for a data line (13) for transferring the at least one variable, in particular a current limiting value (Iref) from or to a storage element (14) by way of the microcontroller (12), and optionally by way of an internal data bus (15). The invention also relates to use of the device in the context of batteries of fans, and program-controlled current limitation for startup of an electric motor (10).

Abstract: The rotation speed of an electric motor (9) is controlled by a controller (6) which receives its setpoint from a characteristic function (23). The characteristic function (23) calculates a setpoint for the controller (6) on the basis of an originally analog variable A (2) that is converted to digital by an A/D converter AD (10), with the aid of support values of a “MEM+DATA” characteristic that are stored in a memory (4); those values not predefined by the support values are calculated by interpolation.

Abstract: The invention concerns a method for nonvolatile storage of at least one operating data value of an electric motor (32). The latter comprises a microprocessor or microcontroller (23) that controls its commutation, and it comprises a nonvolatile memory (74). In this method, when the motor (32) is switched on, an old operating data value is transferred from the nonvolatile memory (74) into a volatile memory (97) associated with the microprocessor (23) and saved there as a variable. The variable is updated by the microprocessor in the time intervals between the commutation operations (FIG. 13). At intervals of time, the operating data value saved in the nonvolatile memory (74) is replaced by the updated operating data value corresponding to the present value of the variable. A motor for carrying out this method is described.

Abstract: The invention concerns a method for controlling the commutation in an electronically commutated motor (20) which comprises a stator having at least one phase (24, 26), and a permanent-magnet rotor (22), and with which a current limiter (36, 58) and a controller (18) for regulating a motor variable are associated. The current limiter (36, 58) serves to limit the current (I) in the at least one phase (24, 26) to a setpoint value. The regulation by means of the controller (18) is accomplished by modifying the distance in time (W) between switching on (t1) and switching off (t2) of the current (i1, i2) in the at least one phase. In this method, the setpoint value to which the current limiter limits the current (i1, i2) in the relevant phase is modifiable.

Abstract: An electronically commutated motor has a rotor (108), a stator having a stator winding arrangement (102), and a full bridge circuit (137) for controlling the current (i1, i2) in the stator winding arrangement (102); in the full bridge circuit (137), first semiconductor switches (114, 130) are connected to a first DC supply lead (116) and second semiconductor switches (132, 136) to the other DC supply lead (122), said second switches being bidirectionally conductive of current in the switched-on state. The motor has an arrangement (172, 198, 188) for opening the first semiconductor switches (114, 130) and for closing the second semiconductor switches (132, 136) during a predetermined operating state. An arrangement (202) is provided for monitoring the direction of the current (i1, i2) which flows in the second semiconductor switches (132, 136) when the latter are conductive during the predetermined operating state.

Abstract: An improved method of commutating an electronically commutated DC motor shuts off application of power between the end of one current pulse and the beginning of the subsequent current pulse. Based upon the instantaneous rotation speed, one calculates at what instant to shut off the power. During the power interruption, the disconnected winding is operated in short-circuit mode using two MOSFET transistors, and the decay of the current is monitored. When the current reaches a predetermined reduced value, the terminals of the winding are switched to a high-resistance state, until the subsequent current pulse is started. This has the advantage that less reactive power occurs during operation, and one need not install as bulky a storage capacitor as the capacitors used heretofore.

Abstract: In a method for commutating an electronically commutated motor, a predictive calculation is made of a first time span that the rotor will need in order to pass through a specified rotation angle that lies between a first rotational position (∂0) and a later second rotational position (∂1) at which a switching operation is to be effected in the motor. Upon actual passage through the first rotational position, a reference time is identified and stored. The time difference between the present time and the stored reference time is then monitored repeatedly and compared to the first time span; and when a specified relationship exists between the time difference and the first time span, the switching operation is performed.

Abstract: In a method for controlling a physical variable in an electronically commutated motor, current is supplied to the stator winding arrangement (102) of the motor in the form of current blocks. The interval (BW) between the switch-on command and switch-off command for controlling those current blocks, i.e. the length (BW) of the control signals, is influenced by a control apparatus, and the effective current value of those current blocks is influenced by setting a pulse duty factor (pwm). The length of the control signals is limited in both directions. If a control signal becomes shorter than a specified lower limit, the pulse duty factor (pwm) is decreased, so that the effective value of the current falls and the length (BW) of the current blocks is increased by the control system. If a control signal becomes longer than a specified upper limit, the pulse duty factor is increased, so that the effective value of the current rises and the length of the current blocks decreases in compensatory fashion.

Abstract: The rotation speed of an electric motor (9) is controlled by a controller (6) which receives its setpoint from a characteristic function (23). The characteristic function (23) calculates a setpoint for the controller (6) on the basis of an originally analog variable A (2) that is converted to digital by an A/D converter AD (10), with the aid of support values of a “MEM+DATA” characteristic that are stored in a memory (4); those values not predefined by the support values are calculated by interpolation.

Abstract: The rotation speed of an electric motor (9) is controlled by a controller (6) which receives its setpoint from a characteristic function (23). The characteristic function (23) calculates a setpoint for the controller (6) on the basis of an originally analog variable A (2) that is converted to digital by an A/D converter AD (10), with the aid of support values of a “MEM+DATA” characteristic that are stored in a memory (4); those values not predefined by the support values are calculated by interpolation.

Abstract: A watchdog circuit for a microprocessor which has a reset input and a control output, which output, when operation is normal, periodically delivers, under program control, a signal (P0B2) of predefined duration (t1); and having a capacitor (32) that can be charged via a charging circuit; having a discharging circuit (40, 42), controlled by the control output, for said capacitor (32), for periodic discharge thereof during the predefined duration (t1); the charging circuit and discharging circuit being adapted to the program sequence of the microprocessor such that when the microprocessor is operating normally, charging of the capacitor via the charging circuit corresponds respectively to discharge thereof via the discharging circuit; so that the voltage at said capacitor rises and falls within a predefined voltage range; and having an apparatus (30), for monitoring the charge state of said capacitor (32), which, in the presence of a charge state thereof that does not occur in normal operation, effects a reset

Abstract: An electronically commutated motor has at least two winding phases (112, 114) which are wound together or otherwise inductively coupled. Current in each phase is controlled by a respective power transistor (124, 128). An integrated circuit controller (146) receives signals from a Hall sensor (118) and generates rotor position output signals (OUT1, OUT2) which are oppositely phased and are applied to the bases of the respective power transistors (124, 128) so that the power transistors never both conduct at the same time. Further, a pair of latching transistors (162, 172) and a pair of base drain resistors (164, 174), connected to respective bases of the power transistors (124, 128) are provided, in order to assure “soft” switching of the power transistors at low RPM, yet prompter switching and higher efficiency at high RPM. These additional components also ensure a sufficiently long current gap between switch-off of one power transistor and switch-on of the other power transistor.

Abstract: An electronically commutated claw pole motor has an external rotor (42) with a shaft (40) and a rotor magnet (62). The claw pole motor contains a stator (64) which has a first soft ferromagnetic stator pole piece (74) located on its side facing away from the external rotor (42). The stator pole piece is provided with first claw poles (82, 84) projecting toward the external rotor (42). The stator has a second soft ferromagnetic stator pole piece (76) located on its side facing the external rotor (42). The second soft ferromagnetic pole piece is provided with second claw poles (88, 90) extending from the external rotor (42) and having a larger axial extension (h2) than the first claw poles (82, 84) and projecting into gaps (92) between the first claw poles (82, 84). An axial bearing (44, 46) supports the end (44) of the shaft (40) which faces away from the external rotor (42).

Abstract: A memory device, e.g. a capacitor, is provided for a collectorless DC motor. This component is charged whenever a particular rotor position is reached. In so doing, a voltage value or quantity on this memory device is changed. This quantity is compared to another quantity, which is dependent on a desired parameter, e.g. ambient temperature or gas or dust concentration. A reference signal is produced when a particular reference criterion is satisfied. The difference between the beginning of this reference signal and a second predetermined rotor position, which follows the initial predetermined rotor position with respect to time, is measured, and on the basis of this measurement, the current flow of the collectorless DC motor is influenced or regulated. In particular, the current can be toggled on and off as the rotor passes certain predetermined positions.

Abstract: An electronically commutated motor (10) has a permanent-magnet external rotor (58) and an inner stator (20) with claw-poles (30,32; 44,46). Preferably, the claw-poles extend axially from opposite directions along the outside of the stator (20) and are interdigited. A galvanomagnetic sensor (14) generates a rotor position signal, based upon measurement of a stray or cross-flux field (.phi..sub.1) of the rotating permanent-magnet external rotor (58,66). Between the claw-poles of the stator (20) are a plurality of neutral field zones (52). The motor turns in a predetermined direction (72) and the galvanomagnetic sensor (14) is positioned adjacent the stator (20) at a location which is circumferentially displaced with respect to a neutral field zone (52), in order to trigger early commutation of current to windings (22,24) of the motor (10).

Abstract: An improved motor for driving a variable-speed fan used, for example, to prevent overheating of electronic equipment, features an electronic controller which sends current pulses through the stator winding(s) of the motor, and varies the slope of trailing edges of these pulses in accordance with at least one sensed operating parameter of the motor, such as temperature of the power semiconductors which control the motor current. The slopes are steepened at high motor speeds to reduce electrical losses, and flattened at low motor speeds to minimize noise. Another feature of the improved motor provides for fail-safe, high-speed operation of the fan when the sensed value of the operating parameter is implausible, for example when a lead from a temperature-dependent sensing resistor breaks. In a preferred embodiment, a bridge circuit is used, which includes a transistor in one diagonal of the bridge circuit.

Abstract: An electric motor (10) particularly a low-voltage collectorless dc motor, has a microprocessor (18, 40) with a reset input (24). Further, it has a device (26) which, during the running of the motor, generates signals (R) which depend upon the rotational position of the rotor (14) of the motor (30). These signals are applied to the reset input (24) and have the effect that the microprocessor is reset to predefined starting states or conditions, at times controlled by the turning of the rotor (14).