A power conversion device includes a main board, a connector module, an input conversion module, a capacitor, an output conversion module, a control module and a conducting part. The main board includes two lateral edges along a first direction and two lateral edges along a second direction. The connector module is mounted on the main board, and includes an input connector and an output connector. The output connector is located under the input connector. The input conversion module, the output conversion module and the control module are perpendicularly mounted on the main board. The conducting part is in parallel with the control module and electrically coupled with the input connector or the output connector. The connector module, the input conversion module, the capacitor and the output conversion module are mounted on the main board and arranged in a line along the second direction.

A transformerless DC to AC inverter providing an AC output at a power line voltage and at a power line frequency suitable for driving AC loads or appliances and having DC bias measurement circuitry for continuously assessing the magnitude of any DC bias component on the AC output, such as due to fault conditions or non-linear loads, and operative to eliminate or reduce any unwanted DC bias component from the AC output.

A method for operating an inverter and an inverter configured to convert DC power supplied from a DC power source into AC power supplied to an AC network by applying operational parameter limits which define limits for allowed operating points of the inverter, collect, during the converting, data of operational conditions related to the inverter, determine on the basis of the collected data whether the set operational parameter limits can be optimized with regard to one or more optimization criteria, and in response to determining that the set operational parameter limits can be optimized, adapt one or more of the set operational parameter limits applied in the converting on the basis of the collected data.

Systems and methods to estimate magnetic flux in a switched mode power supply are disclosed. An example welding-type power supply includes a switched mode power supply, comprising: a transformer configured to transform an input voltage to a welding-type voltage; a capacitor in series with a primary winding of the transformer; and switches configured to control a voltage applied to a series combination of the primary winding of the transformer and the capacitor; a voltage estimator coupled to the transformer and configured to output a signal representative of an alternating-current (AC)-coupled voltage at the capacitor; and a flux accumulator to determine a net flux in the transformer based on the voltage applied to the series combination of the primary winding of the transformer and the capacitor

A motor control apparatus includes: a smoothing capacitor; an inverter circuit; a torque limiter; and a field-weakening control device. The smoothing capacitor smooths the direct current power. The inverter circuit converts the smoothed direct current power to alternating current power. The torque limiter limits motor torque based on a torque limit value calculated from a direct current voltage applied to the smoothing capacitor, limiting the motor torque in a power running direction to a first torque value when the direct current voltage drops to a first threshold. The field-weakening control device weakens a field and raises an induced motor voltage and the direct current voltage when the power running direction motor torque is limited to the first value. The torque limiter limits the power running direction motor torque to a second value greater than the first value when the direct current voltage rises from the first to a second threshold.

A symmetry control circuit for a trailing edge phase control dimmer circuit for controlling alternating current (AC) power to a load, the symmetry control circuit including: a bias signal generator circuit configured to monitor non-conduction periods of each half cycle of said AC power for an elapsed duration of the non-conduction periods, and generate a bias signal voltage based on the elapsed duration, whereby an amplitude of the bias signal voltage is proportional to the elapsed duration of the non-conduction periods; and a bias signal converter circuit configured to convert the bias signal voltage to a bias signal current, wherein the bias signal current is added to a reference current of a conduction period timing circuit configured to determine said conduction periods, and wherein the conduction period timing circuit is configured to alter one of the conduction periods immediately following one of the non-conduction periods based on the bias signal current when added to the reference current to compensate for a phase shift of a zero-crossing of said one of the non-conduction periods corresponding to an elapsed duration of said one of the non-conduction periods so as to restore symmetry of the non-conduction periods of each half cycle of AC power.

To include a carrier-wave generation unit to generate a first carrier wave with a frequency higher than a modulation wave, and a second carrier wave with a frequency lower than the first carrier wave, a comparison unit to compare either the first carrier wave or the second carrier wave to the modulation wave in order to generate a switching signal. The carrier-wave generation unit outputs the second carrier wave when a modulation factor is lower than a threshold value, and outputs the first carrier wave when the modulation factor is equal to or higher than the threshold value. When the modulation factor is equal to or higher than the threshold value, a power conversion unit operates in an overmodulation mode, in which the switching operation is stopped during a period longer than one cycle of the second carrier wave.

Disclosed are implementations that include a power converter system including a non-isolated N-phase DC/AC power converter, for N1, with a DC voltage section and an N-phase AC voltage section, with the power converter including energy storage arrangements for each of three phases of the AC voltage section. The energy storage arrangements are commonly electrically coupled to the terminals of the DC voltage section. The system further includes a controller to control voltages at the energy storage arrangements, with the controller including one or more switching devices to control voltages at one or more terminals of the energy storage arrangements, and at least one model predictive control (MPC) module to generate control signaling, based on electrical operational characteristics of at least some of storage elements, to actuate the one or more switching devices to establish zero sequence voltage stabilization behavior at the terminals of the energy storage arrangements.

Systems and methods for a high-efficiency power converter incorporating a half-bridge topology with one or more an additional upper capacitor and a drain-source capacitor. The converter includes DC voltage terminals and a DC link capacitor coupled across a positive and negative DC terminal of the DC voltage terminals. The converter further includes a power switching element pair including a high side switch and a low side switch coupled together at a midpoint node. The converter further includes an LC filter having a switch-side inductor, a lower capacitor coupled between a second end of switch-side inductor and the negative DC terminal; and an upper capacitor coupled between the second end of the switch-side inductor and the positive DC terminal. The converter may further include drain-source capacitors coupled across the drain and source terminals of the switches.

A power conversion device includes an inverter that generates an inverter voltage, a filter that receives the inverter voltage and outputs an output voltage, a detector that detects a DC component of the output voltage, a feedback controller that receives an AC voltage command and the DC component and determines an inverter voltage command such that the DC component is equal to a target value which is zero or a value corresponding to an offset error of the detector, and a PWM controller that receives the inverter voltage command and performs pulse width modulation control of the inverter. The feedback controller computes a compensation amount for compensating for the DC component and determines, as the inverter voltage command, the AC voltage command on which a product of an absolute value of a sine wave synchronized with a period of the AC voltage command and the compensation amount is superimposed.