An apparatus can comprise a circuit and an electrical element coupled to the circuit. The circuit can include a pulse generator to generate an electrical pulse having a first power and a load. The electrical element can be configured to receive heat that is converted into electrical energy by the circuit to apply a second power, greater than the first power, to the load.

An apparatus can comprise a circuit and an electrical element coupled to the circuit. The circuit can include a pulse generator to generate an electrical pulse having a first power and a load. The electrical element can be configured to receive heat that is converted into electrical energy by the circuit to apply a second power, greater than the first power, to the load.

An apparatus includes a power converter having switches coupled to input voltage rails and to opposing terminals of a coil to be energized. The switches are configured to be turned ON or OFF to conduct or block current, respectively, responsive to switch control signals. The apparatus also includes a controller to generate the switch control signals to compel the power converter to selectively operate (i) in a normal mode in which the switches are periodically turned ON and OFF to supply current from the input voltage rails to the coil to energize the coil, and (ii) in a protection mode in which first switches are continuously turned ON, and second switches are continuously turned OFF, to interrupt the current, and to circulate an initial current, flowing in the coil when the protection mode is entered, through the power converter and the coil so that the initial current decays toward zero.

The present application relates to a bidirectional digital switching power amplifier based on a magnetic suspension drive platform and its multi-step current predictive control method. The control method includes the following steps: establishing a prediction model of a bidirectional digital switching power amplifier; introducing a feedback correction term for a closed loop prediction; calculating an optimal modulation duty cycle through a value function; generating, according to the obtained modulation duty cycle, four PWM drive signals by a pulse width modulation module to control four switch tubes respectively to achieve current prediction control. The present application effectively improves the system control accuracy with small steady-state error, small on-line computation amount, simple algorithm, easy digital realization, and good practical value and application prospect.

This motor control device has an inexpensive configuration and enhances motor current target value tracking. This motor control device has an H bridge circuit that has a switching element and is connected to a motor coil provided in a motor, and a control means that drives the switching element at each prescribed PWM period and specifies an operation mode for the H bridge circuit from among a charge mode for increasing the motor current (Icoil) flowing through the motor coil, a fast decay mode for decreasing the motor current, and a slow decay mode. In each PWM period, the control means selects one of the operation modes on the basis of the result of comparing the motor current and a current reference value (Iref) before the time that has passed from the start of the PWM period reaches a prescribed current control re-execution time (Tr) and selects one of the operation modes on the basis of the result of comparing the motor current and the current reference value after the time that has passed reaches the current control re-execution time.

In a power converter, a first electrical path connects between the series resonant circuit and a selected terminal from the high- and low-side input and output terminals of the power converter. An auxiliary diode is provided on one of the series resonant circuit and the first electrical path. An auxiliary switch, when turned on, causes an inductor current to flow through the auxiliary diode to the resonance inductor, thus storing electromagnetic energy into the resonance inductor, and causes the resonance inductor and the capacitance component of the series resonant circuit to resonate with each other. A second electrical path bypasses the auxiliary switch for flow of the inductor current. A discharge unit is provided on the second electrical path. The discharge unit is activated to discharge the electromagnetic energy stored in the resonance inductor via the second electrical path.

A latch system includes a releasably secured latch or keeper and a solenoid assembly. The solenoid assembly has a solenoid driver coupled to a power supply, a switching circuit connected with the solenoid driver, and a function generator to selectively adjust a frequency of a pick current output from the power supply and provided to the solenoid driver. The frequency is adjusted until the pick current induces a resulting vibration of said latch system sufficient to free a preloaded latch or keeper. The adjusted frequency may be a target frequency or a range of frequencies. Also included may be a preload sensor. When a preload is sensed, the frequency may be adjusted by the function generator until the pick current induces a resulting vibration of said latch system sufficient to free a preloaded latch or keeper.

In one example, a circuit includes a voltage source, an inductive load, a capacitor, a switching unit, and a load unit. The switching unit is configured to operate in a first state and a second state. The switching unit couples the inductive load to the voltage source during the first state. The switching unit couples the inductive load to the capacitor during the second state. The load unit is configured to receive energy from the capacitor based on a comparison of a voltage of the capacitor and a reference voltage.

Disclosed are a switching apparatus including an internal circuit using an inductive element and a control method thereof. The switching apparatus includes a switch that regulates a current of the inductive element, and a signal control circuit that arithmetically calculates a turn-off time point of the switch by using a monitoring voltage corresponding to the current of the inductive element, a sampling voltage of the monitoring voltage, and a reference voltage corresponding to a target average current of the inductive element, and controls the switch.

A load drive controlling device includes a dulling controller, a dulling adjuster, and a Proportional Integral (PI) controller. The dulling adjuster sets a first electric current value for a dulling adjustment operation according to a change trend of a target electric current value in an inductive load. The dulling adjuster performs the dulling adjustment operation on the first electric current and limits a dulled value based on a guard value. The PI controller performs a PI control based on a deviation between the dulled value and an actual value of the electric current. The dulling controller sets the first electric current value and the guard value according to a change trend of the target electric current value. In such a configuration, the load drive controlling device improves an electric current response while preventing an over-accumulation of an integration value.