Disclosed herein are reluctance actuators and methods for feedback control of their applied force. Embodiments of the reluctance actuators include an electromagnet positioned to deflect a metallic plate to provide a haptic output. The control of the force is provided without force sensors (sensorless control) by monitoring voltage and/or current (V/I) applied during an actuation. For a given intended force output, an electrical parameter value (flux, current, or other parameter) is read from a look up table (LUT). The LUT may store a present value of the inductance of the reluctance actuator. The feedback control may be a quasi-static control in which the LUT is updated after actuation based on the monitored V/I. The feedback control may be real-time, with a controller comparing an estimated electrical parameter value based on the measured V/I with the value from the LUT.

A smart accessory device includes an actuator and is designed to be used to actuate an operating mechanism of a circuit breaker in order to either open or close the separable contacts of the circuit breaker. The accessory can be one of a shunt trip, spring release, or under voltage release device. The actuator includes a solenoid and plunger. The accessory determines the operating condition of the actuator based on how much current flows through the coil when the power source provides power to the accessory device, and continually executes a coil diagnostic to determine the operating condition of the coil while power is being provided to the accessory device. If the accessory fails to trip the circuit breaker when required, the accessory can determine whether the failure was due to either of the solenoid or the plunger.

An object is to provide a new electronic control unit that can improve detection accuracy of a sense current even in a region where the current value of the sense current is small. Provided is a sense current detection unit including a plurality of sense transistors that have different current flow rates and that are connected to current output transistors controlling a current flowing in a coil load. The current in the sense current detection unit is input to an analog/digital converter, and the current value of the current flowing in the sense current detection unit is converted into a digital value. The current value of the current flowing in the sense current detection unit is increased through a combination or a selection of the plurality of sense transistors of the sense current detection unit in a region where the current value of the main current of the current output transistors is small compared to a region where the current value of the main current is large.

A coil actuator for low and medium voltage applications including: a coil electromagnet having a single coil winding and a movable member; and a power and control unit including: a power circuit operatively coupled with the coil electromagnet, the power circuit including input terminals for receiving an input voltage and an intermediate node, the electromagnet being electrically connected with the input terminal and the intermediate node, the power circuit further including a discharge circuit, which is electrically connected with the first input terminal and the intermediate node in parallel with the coil winding, and a switch circuit, which is electrically connected with the intermediate node and the second input terminal, the switch circuit including at least a power switch; a controller operatively coupled with the power circuit to drive the at least a power switch to control of an input current circulating through the power circuit, the controller being adapted to perform a PWM control of the input current to operate the coil electromagnet; a power supply circuit adapted to feed the controller. The power supply circuit is electrically connected with the intermediate node and the controller.

A system and a method for diagnosing a contactor life using contactor coil current, whereby, after a current value of a current contactor coil is determined based on a resistance value and a voltage value according to a real-time temperature of a contactor coil, whether contactor lifetime has expired and an abnormal operation thus occurs can be previously diagnosed and predicted on the basis of whether an average current value when a corresponding contactor operates a preset number of times or more exceeds a threshold value.

In an example, a system for applying an agricultural product includes a valve and a solenoid. For instance, the valve includes a coil that generates a magnetic flux. The system includes a valve controller. The valve controller is configured to measure one or more electrical characteristics of at least one of the coil or a dissipation element. In some examples, the valve controller determines an actual duty cycle of a valve operator of the valve using the measured electrical characteristics. The valve controller determines a magnetic flux correction, for instance based on a difference between the actual duty cycle and a specified duty cycle. The valve controller operates the valve operator according to the specified magnetic flux and the magnetic flux correction to guide the actual duty cycle toward the specified duty cycle.

Methods and apparatuses for connecting multiple loads with a common return pin in engine control module application are disclosed. Only one of the multiple loads can be connected to a power source at a time. At the high side, each load is coupled to the power source through a respective pin at a connector. At the low side, the multiple loads share a common return pin at the connector that connects the loads to the ground. When a first load is connected to the power source at the high side, a first low side driver circuit is used to connect the first load to the ground at the low side. When a second load is connected to the power source at the high side, the second low side driver circuit is used to connect the second load to the ground at the low side.

Electropneumatic solenoid valve includes an electromagnetic actuator with an energizable coil and a solenoid armature movable relative to the coil, an air chamber with three air channels, and a valve member. The three air channels include first and second air channels and a control air channel. The valve member, in a first closed position, closes the first air channel and releases the second air channel and which, in a second closed position, closes the second air channel and releases the first air channel. The valve further includes a driver movable in a first and second actuating directions and that connects the valve member to the solenoid armature, a driver-pretensioning spring arranged between the driver and the solenoid armature, to provide a pretensioning force to the driver, and a restoring spring between the driver and the electromagnetic actuator to provide a restoring force to the driver against the driving direction.

A coil actuator for low and medium voltage applications comprising a coil electromagnet provided with a single coil winding and a movable anchor and a power and control unit comprising: a power circuit operatively coupled with said coil electromagnet, said power circuit comprising input terminals, at which said power circuit receives an input voltage; a PWM controller operatively coupled with said power circuit, said PWM controller being adapted to control an input current flowing through said power circuit to obtain and maintain an average operating level selected an excitation current feeding said coil electromagnet. Said PWM controller is adapted to set a plurality of reference values for said input current to control said input current, each reference value for said input current being selected among said plurality of reference values depending on the behavior of said input voltage.

Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level, and an elapsed time from the application of the fixed voltage. The controller may compare the amount of time elapsed from the application of the fixed voltage to an expected amount of elapsed time from the application of the fixed voltage to the I/P coil after which a digital logic line trip will occur for a properly functioning I/P coil and diagnose, based on the comparison, a failure in the I/P converter.