A communication system for use in a switching module includes a low-side control block coupled to control switching of a low-side switch of the switching module. The low-side control block is further coupled to be referenced with a low-side reference system ground. A high-side control block is coupled to control switching of a high-side switch of the switching module. The high-side control block is further coupled to be referenced with a floating node of the switching module. During steady state operation, the low-side control block is coupled to send signals during each switching cycle to the high-side control block to turn the high-side switch on and off. A status update is communicated from the high-side control block to the low-side control block through a first single-wire communication link.

Provided are a protection circuit for a brushless DC motor, and a control device. The protection circuit is applied to a control device for a brushless DC motor, the control device including a main control chip and a protection circuit for driving a brushless DC motor. The protection circuit includes a sampling signal input end (RNF), a first resistor (R1), a first capacitor (C1), a second capacitor (C2), a comparator (IC2) and a switching element (IC1), connected together in a preset structure.

A method for protecting a controllable semiconductor switch from overload and short-circuiting in a load circuit, the methodincluding detecting an output voltage of the semiconductor switch;comparing a detected output voltage with a predicted switching progress; anddeactivating the semiconductor switch if the detected output voltage is lower than the predicted switching progress.

A communication system for use in a switching module includes a low-side control block coupled to control switching of a low-side switch of the switching module. The low-side control block is further coupled to be referenced with a low-side reference system ground. A high-side control block is coupled to control switching of a high-side switch of the switching module. The high-side control block is further coupled to be referenced with a floating node of the switching module. During steady state operation, the low-side control block is coupled to send signals during each switching cycle to the high-side control block to turn the high-side switch on and off. A status update is communicated from the high-side control block to the low-side control block through a first single-wire communication link.

The mechanism enables torque protection in a brushless motor without the need to use measurement of the current drawn, establishing the torque level based on measurement of the brushless motor rotation speed. The rotation speed corresponding to the nominal torque has therefore been previously established so that when there is over-torque, the rotation speed is decreased. This makes it possible to infer that there is over-torque, thus achieving torque protection for brushless motors which is effective, simple and highly economical. The mechanism has the following: A power supply (1), a rotation direction setter (2), a control unit (3) which is connected to the rotation direction setter (2); a brushless motor (5) which has a connection for sending a BREAK instruction from the control unit (3) to the motor (5), a signal which is sent when a shutdown occurs due to over-torque.

A protection circuit for an electric motor with a single phase winding, consisting of two coil sections with central tapping, wherein the two coil ends of the coil sections are each connected to ground via a switching element. The task of the invention is for an electric motor of this type to ensure a thermal relief for the switching elements, improved and smoother running, reduced warming of the printed circuit board, improved EMC characteristics, a more robust design of the overall switching, a focused conduction of the losses and an extra protection against any surge impulses from a mains network.

A direct-current (DC) motor control device includes first and second switches, a conducting element and a power storage element. The power storage element, the conducting element and the second switch are connected to each other and form a loop, and the first switch is connected to a common node between the power storage element and the conducting element. When the DC electric power source is normally connected to the DC motor control device, the first switch is turned on, and the conducting element establishes a unidirectional conduction from a DC motor to the power storage element while the second switch is turned off.

An over-current protection method and circuit for a DC Inverter is provided in the present invention. Said over-current protection circuit comprises: a sampling unit for sampling output currents from a power module to form a sampling signal; a signal-processing unit for amplifying with various magnification factors and low-pass filtering the sampling signal to generate a first over-current signal and a second over-current signal; a signal-generating unit for generating a first interrupt trigger signal based on the first over-current signal; a comparison unit for comparing the second over-current signal with a reference voltage corresponding to an over-current threshold of a motor, with a comparison result being a second interrupt trigger signal; and a control unit for controlling the power module based on the first interrupt trigger signal, and the motor based on the second interrupt trigger signal. The over-current protection method and circuit provided in the present invention are able to satisfy over-current protection of the power module and the motor of the inverter simultaneously.

A method for protecting a motor from overheating, includes: running a motor in a given parameter P and detecting a real-time temperature R of the motor; comparing the real-time temperature R with a plurality of set temperatures, the plurality of set temperatures including an overheating protection temperature Rm, shutdown temperature Rmax and recovery operation temperature Rmin, Rmin<Rm<Rmax; according to a comparison result, controlling the motor to operate at an initial current value I0, or operate in a reduced current value with respect to the initial current value I0, or stop running; and when the real-time temperature R meets the condition: Rm<R<Rmax, running the motor in an overheating protection mode, where the motor operates in a current value I lower than the initial current value I0, and the current value I decreases with the increase of the real-time temperature R.

The present techniques include methods and systems for detecting a failure in a capacitor bank of an electrical drive system. Embodiments include using discharge resistors to discharge capacitors in the capacitor bank, forming a neutral node of the capacitor bank. In different capacitor configurations, the neutral node is measured, and the voltage is analyzed to determine whether a capacitor bank unbalance has occurred. In some embodiments, the node is a neutral-to-neutral node between the discharged side of the discharge resistors and a neutral side of the capacitor bank, or between the discharged side of the discharge resistors and a discharged side of a second set of discharge resistors. In some embodiments, the node is a neutral-to-ground node between the discharged side of the discharge resistors and a ground potential.