A magnetic core electrical machine includes a plurality of “U”-shaped stator yokes arranged circumferentially with respect to a rotor and either staggered to form a continuous flux return path or displaced relative to permanent magnets of the rotor in order to reduce cogging. Various mechanisms and/or circuits are provided to limit an output of the electrical machine at high speeds, and boost the voltage output at low speeds.

High efficiency magnetic core electrical machine

An electronically commutated motor (20) has connections (56, 62) for connection to a DC source (63). It has a permanent-magnet rotor (22), as well as a first and a second series circuit (40, 50) in each of which, respectively, a stator winding section is connected in series with a first and a second controllable semiconductor switch, with the two series circuits being connected in parallel to form a parallel circuit (52). In a supply line to this parallel circuit (52), a third controllable semiconductor switch (60) controls the power supply from the DC source (63) to the motor (20). A control apparatus is designed to carry out the following steps during operation: influenced by the rotation position of the rotor (22), the capability to supply power from the DC source (63) to one winding section is activated during a potential current-flow phase and the capability to supply power to the other winding section is deactivated, alternately, during this potential current-flow phase. In this case, the potential current-flow phase to the one winding section is in each case separated in time by a commutation process from that of the other winding section. The third controllable semiconductor switch (60) is switched off at a switching time (Figure 4: t64) in order to initiate a commutation process, during a potential current-flow phase. The first or second semiconductor switch (34, 44) which is switched on at the switching time (t64) is kept switched on so that, during operation, a circulating current (i31; i31') flows in the parallel circuit (50) during operation after the third semiconductor switch (60) has been switched off and produces a driving torque in the motor, with this circulating current being monitored. When this circulating current reaches a predetermined low absolute value, the first and/or second semiconductor switch that is switched on at that instant is switched off. Depending on the rotation position of the rotor (22), the potential current-flow phase in the one winding section is deactivated, and that in the other winding section is activated, as part of the commutation process, and the third semiconductor switch is switched on again.

Method for operating and electronically commutated motor, and motor for carrying out a method such as this

This disclosure relates generally to valves, and more particularly, to gas valve assemblies. In one example, a valve leakage test may be performed on a valve assembly including a valve body with a first valve and a second valve, where the valves may be positioned across a fluid path in the valve body with an intermediate volume between the valves. A pressure sensor may be in fluid communication with the intermediate volume and may sense a measure that is related to the pressure in the intermediate volume. The pressure sensor may communicate with a controller to determine a measure that is related to a pressure change in the intermediate volume and compare the measure that is related to a pressure change to a first and/or second threshold value. The controller may output a signal if the measure meets and/or exceeds the first and/or second threshold value.

Gas valve with valve leakage test

This disclosure relates generally to valves, and more particularly, to gas valve assemblies. In one example, a valve assembly may be configured to perform a valve proving test as part of an operational cycle of a combustion appliance coupled to the valve assembly. The valve assembly may include a valve body having a fluid path, first and second valve sealing members translatable between an opened position and a closed position, and one or more pressure sensors in fluid communication with an intermediate volume of the fluid path between the first and second valve sealing members. A valve controller may be in communication with the pressure sensor and may monitor a measure related to a pressure change rate in the intermediate volume. The valve controller may then output a signal if the measure related to a pressure change rate in the intermediate volume meets and/or exceeds a threshold value.

Gas valve with electronic valve proving system

The invention relates to a two-phase electronically-commuted DC-motor, comprising a permanent magnetic rotor (36), terminals (28, 30) for connecting the motor to a power supply (22) and a stator (102) with a winding arrangement. The above has a first winding phase (52), provided with a first controllable semiconductor circuit (70), for control of the current in the first winding phase (52) and a second winding phase (54), provided with a second controllable semiconductor circuit (80), for control of the current in the second winding phase (54). The first and second semiconductor circuits (70, 80) together define a partial amount of semiconductor circuits for the electronic commutation. The motor also comprises a third controllable semiconductor circuit (50), arranged in a line from one of the terminals (28, 30) to the winding (52, 54), a device (74) for prevention of a reverse current, arranged in a common line to the semiconductor circuits (70, 80) of the partial amount and an arrangement for carrying out the following steps: depending on a desired operating condition of the motor (20), the third semiconductor circuit (50) is alternately blocked and activated without switching the semiconductor circuit from the partial amount currently in a conducting state off, such that, during operation, following a blocking of the third semiconductor circuit (50), a decaying ring current (i2, i3), flows through the semiconductor circuit from the partial amount currently in a conducting state and the other semiconductor circuit from the partial amount or a recovery diode (76, 81 ), provided therein and through the first and second winding phase (52, 54), generating a torque on the motor when the energy from the power supply (22) is temporarily interrupted.

Method for operation of a two-phase electronically-commuted motor and motor for carrying out said method

An electronically commutated motor (20) has terminals (56, 62) for connection to a DC power source (63). It has a permanent magnetic rotor (22), further comprising a first and a second series circuit (40, 50), in each of which a stator winding is connected in series with a first or second controllable semiconductor switch, which two series circuits parallel to a parallel circuit (52) are switched. In a supply line to this parallel circuit (52) controls a third controllable semiconductor switch (60), the power supply from the DC power source (63) to the motor (20). A control device is designed to carry out the following steps during operation: Depending on the rotational position of the rotor (22), the possibility of energy supply from the DC source (63) to one winding strand during a potential energization phase is alternately activated, and the possibility of energy supply to the other winding strand is deactivated during this potential energization phase. In this case, the potential energization phase of one winding strand is separated in time by a commutation from that of the other winding strand. During a potential energization phase, the third controllable semiconductor switch (60) is blocked at a switchover time (FIG. 4: t64) in order to initiate a commutation process. The at the switching time (t64) conductive first or second semiconductor switch (34, ...

Electronically commutated motor operating method for drive system, involves maintaining two semiconductor switches e.g. FET, in conductive state such that circular current flows in parallel circuit after disabling third switch

An electronically commutated one-phase motor ( 20; 20 ′) has a stator having at least one winding strand ( 30, 32; 30 ′), and it has a permanent-magnet rotor ( 22 ) that induces, as it rotates, a voltage (u ind ) in the winding strand. The motor further has an electronic calculation device or microcontroller ( 26 ) which is configured to execute, during operation, the following steps repetitively: sampling the induced voltage (u ind ) in a currentless winding strand, for example, during a half-wave of the induced voltage, in order to obtain a plurality of analog voltage values; digitizing the analog voltage values in order to obtain a plurality of digitized voltage values; and processing the plurality of digitized voltage values to ascertain the instantaneous rotation direction of the motor rotor. The control circuit then can use these data to assure reliable motor start-up, regardless of any external driving forces which occur.

One-phase brushless motor

The motor (20) has an electronic computing device (26) to repeat a starting procedure for a prolonged time duration, when a time duration of a starting current pulse (i-30) is prolonged according to termination of a circle current (i power star) inspite of generation of an induced voltage. The computing device repeats the starting procedure with a shortened time duration, when the induced voltage is not generated on the side of a winding strand (30). The computing device switches the motor to normal commutation, when the induced voltage is generated on the side of the winding strand.

Jens Löffler

Papers

Method for operating and electronically commutated motor, and motor for carrying out a method such as this

Method for operation of a two-phase electronically-commuted motor and motor for carrying out said method

Electronically commutated motor operating method for drive system, involves maintaining two semiconductor switches e.g. FET, in conductive state such that circular current flows in parallel circuit after disabling third switch

One-phase brushless motor

Single phase electronically commuted motor