An inductor current-sensing circuit for measuring a current in an inductor includes (a) a first RC network coupled between a first terminal of the inductor and a reference voltage source; and (b) a second RC network coupled between a second terminal of the inductor and the reference voltage source. The first RC network and the second RC network each have a time constant substantially equal to the ratio between the inductance and the DC resistance of the inductor. The inductor which current is being measured may be a primary inductor of a four-switch buck boost converter receiving an input voltage and providing an output voltage.

An isolation transformer boost system. The system including a power supply and an isolation transformer. The isolation transformer including a primary winding electrically connected to the power supply, a secondary winding, a first voltage tap, and a second voltage tap. The isolation transformer is configured to, in response to a command from an electronic processor, disconnect a connection from the first voltage tap and establish a second connection from the second voltage tap.

An isolation transformer boost system. The system including a power supply and an isolation transformer. The isolation transformer including a primary winding electrically connected to the power supply, a secondary winding, a first voltage tap, and a second voltage tap. The isolation transformer is configured to, in response to a command from an electronic processor, disconnect a connection from the first voltage tap and establish a second connection from the second voltage tap.

The invention discloses a converter adaptable to a wide range output voltage and a control method thereof. The converter comprises a PWM half-bridge circuit. The control method comprises the steps of: controlling the PWM half-bridge circuit to enter into a discontinuous conduction mode by regulating a switching frequency; when the PWM half-bridge circuit is operated in the discontinuous conduction mode, oscillation occurs among the output inductor, a magnetizing inductor of the transformer and a parasitic capacitor of the PWM half-bridge circuit, and when a center point voltage of the primary switching bridge arm reaches a valley or a peak, turning on the corresponding power switch. The invention reduces switching loss by controlling the corresponding power switch in the PWM half-bridge circuit to turn on when a voltage across the power switch is oscillated to valley.

The invention discloses a converter adaptable to a wide range output voltage and a control method thereof. The converter comprises a PWM half-bridge circuit. The control method comprises the steps of: controlling the PWM half-bridge circuit to enter into a discontinuous conduction mode by regulating a switching frequency; when the PWM half-bridge circuit is operated in the discontinuous conduction mode, oscillation occurs among the output inductor, a magnetizing inductor of the transformer and a parasitic capacitor of the PWM half-bridge circuit, and when a center point voltage of the primary switching bridge arm reaches a valley or a peak, turning on the corresponding power switch. The invention reduces switching loss by controlling the corresponding power switch in the PWM half-bridge circuit to turn on when a voltage across the power switch is oscillated to valley.

There is disclosed new topology for an Electronic Voltage Regulator (EVR) which can apply additive or subtractive (aka boost or buck) voltages to compensate for an increase or decrease in system voltages. This regulator employs a ladder of power capacitors which are in series and connected across the input voltage to apply different levels of voltages to a controlled or regulated transformer. Considering this, the proposed EVR can be utilized as a replacement for conventional electromechanical type on-load tap changers or (OLTCs) commonly used in power transformers, and meant to compensate voltage changes in a system. Electromechanical tap changers have some significant issues, such as defined time durations when switching to different taps, as determined by the spring-loaded mechanism's operation; a high malfunction rate due to mechanical switching when causing arcing, and thereby decreasing the operating lifetime of transformers. In this EVR instead of electromechanical taps, a combination of capacitors and TRIACs are used at each voltage level to eliminate arcing effects while increasing the speed of the tap changing process. Furthermore, the electronic regulator can improve the load power factor due to the presence of capacitors. Other advantages over conventional OLTC's is the elimination of a reactor, if used, and the elimination of a tap winding with its numerous tap leads and having correspondingly higher cost. This will reduce the overall size of the active part of the main transformers and improve efficiency by reducing operating losses. In addition, a new failure detection method is included that detects a failed TRIAC to enable the system to continue operating. The failure detection circuit is seamlessly incorporated within the main circuit and has a high-speed detection rate.

There is disclosed new topology for an Electronic Voltage Regulator (EVR) which can apply additive or subtractive (aka boost or buck) voltages to compensate for an increase or decrease in system voltages. This regulator employs a ladder of power capacitors which are in series and connected across the input voltage to apply different levels of voltages to a controlled or regulated transformer. Considering this, the proposed EVR can be utilized as a replacement for conventional electromechanical type on-load tap changers or (OLTCs) commonly used in power transformers, and meant to compensate voltage changes in a system. Electromechanical tap changers have some significant issues, such as defined time durations when switching to different taps, as determined by the spring-loaded mechanism's operation; a high malfunction rate due to mechanical switching when causing arcing, and thereby decreasing the operating lifetime of transformers. In this EVR instead of electromechanical taps, a combination of capacitors and TRIACs are used at each voltage level to eliminate arcing effects while increasing the speed of the tap changing process. Furthermore, the electronic regulator can improve the load power factor due to the presence of capacitors. Other advantages over conventional OLTC's is the elimination of a reactor, if used, and the elimination of a tap winding with its numerous tap leads and having correspondingly higher cost. This will reduce the overall size of the active part of the main transformers and improve efficiency by reducing operating losses. In addition, a new failure detection method is included that detects a failed TRIAC to enable the system to continue operating. The failure detection circuit is seamlessly incorporated within the main circuit and has a high-speed detection rate.

The present disclosure relates to a voltage regulation circuit (100). The voltage regulation circuit (100) comprises a transformer (130) having a primary winding (132) having a first end (132A) and a second end (132B), and a first secondary winding (134) having a first end (134A) and a second end (134B), wherein the first end (132A) of the primary winding (132) is configured to receive an input voltage and the second end (132B) of the primary winding (132) is configured to produce an output voltage, wherein the first end (134A) of the first secondary winding (134) is connected to a neutral node (180), wherein the primary winding (132) produces a primary voltage based on the input voltage, and wherein a secondary voltage of the first secondary winding (134) is out-of-phase to the primary voltage of the primary winding (132); and a first switch (160) configured to connect the second end (134B) of the first secondary winding (134) with the second end (132B) of the primary winding (132), wherein, when the first switch (160) is connected, the output voltage is the secondary voltage.

A system and method for an isolation transformer boost system. The system includes an isolation transformer, a sensor, and an electronic processor coupled to the sensor. The electronic processor configured to receive an electrical characteristic measurement from the sensor, compare the electrical characteristic measurement to a predetermined threshold, and activate an electrical characteristic boost when the electrical characteristic measurement is below the predetermined threshold.

A system and method for an isolation transformer boost system. The system includes an isolation transformer, a sensor, and an electronic processor coupled to the sensor. The electronic processor configured to receive an electrical characteristic measurement from the sensor, compare the electrical characteristic measurement to a predetermined threshold, and activate an electrical characteristic boost when the electrical characteristic measurement is below the predetermined threshold.