摘要:
A system and method of monitoring a photovoltaic (PV) installation includes providing a string of multiple panel interface device enabled PV panels; operatively connecting an inverter to the string; operatively connecting at least one PV panel to the string; discharging an input capacitance of the inverter; comparing a current in the string to a predetermined current threshold value; and controlling connection of the at least one PV panel to the string based on the comparing of the current in the string to the predetermined current threshold value. A panel interface device may be used to discharge the input capacitance of the inverter.
摘要:
A system and method of monitoring a photovoltaic (PV) installation includes providing a string of multiple panel interface device enabled PV panels; operatively connecting an inverter to the string; operatively connecting at least one PV panel to the string; discharging an input capacitance of the inverter; comparing a current in the string to a predetermined current threshold value; and controlling connection of the at least one PV panel to the string based on the comparing of the current in the string to the predetermined current threshold value. A panel interface device may be used to discharge the input capacitance of the inverter.
摘要:
A flyback converter controller with forced primary regulation is disclosed. An example flyback converter controller includes a secondary control circuit to be coupled to a switched element coupled to a second winding of a coupled inductor of a flyback converter. The secondary control circuit is to be coupled across an output of the second winding to switch the switched element in response to a difference between an actual output value at the output of the second winding and a desired output value to force a current in a third winding of the coupled inductor that is representative of the difference between the actual output value at the output of the second winding and the desired output value. A primary control circuit is also included and is to be coupled to a primary switch coupled to a first winding of the coupled inductor. The primary control circuit is to be coupled to receive the current forced in the third winding by the secondary control circuit. The primary control circuit is coupled to switch the primary switch to regulate an output of the flyback converter coupled to the output of the second winding in response to the forced current.
摘要:
A power supply controller controls power supplies for power-up and/or shut-down in a desired sequence. An input voltage for the power supplies powers, and is monitored by, a first control unit having outputs for enabling the power supplies. A second control unit monitors output voltages of the power supplies, and an isolating signal coupler couples signals in both directions between the first and second control units. The second control unit is powered in an isolated manner from the input voltage, conveniently via a transformer constituting the signal coupler. The control units together respond to the monitored voltages for enabling the power supplies in accordance with the desired sequence, information for which can be stored in a non-volatile store. The second control unit can also include enable outputs isolated from the input voltage, and trim outputs for adjusting the monitored voltages.
摘要:
A switch is coupled to a control circuit and to an input of a power converter. The control circuit is coupled to drive the switch in a first operating mode to transfer energy from the input to an output of the power converter when an electrical energy source is coupled to the input of the power converter. The control circuit is coupled to drive the switch in a second operating mode when the electrical energy source is uncoupled from the input. A capacitance is coupled between input terminals of the input of the power converter and is discharged to a threshold voltage in less than a maximum period of time from when the electrical energy source is uncoupled from the input terminals. The control circuit is coupled to drive the switch to have a high average impedance in the first operating mode.
摘要:
A circuit to discharge a capacitance between input terminals of a power system is disclosed. An example circuit includes a control circuit coupled to an input of a power system. The control circuit is coupled to detect whether an electrical energy source is coupled to an input of the power system. A switch is also included and is coupled to the control circuit and to the input of the power system. The control circuit is coupled to drive the switch in a first operating mode when the electrical energy source is coupled to the input of the power system. The control circuit is coupled to drive the switch in a second operating mode when the electrical energy source is uncoupled from the input of the power system. A capacitance coupled between input terminals of the input of the power system is discharged through the switch to a threshold voltage in less than a maximum period of time from when the electrical power source is uncoupled from the input terminals of the power system.
摘要:
A controller that forces primary regulation is disclosed. An example controller includes a switched element to be coupled to a second winding of an energy transfer element of a power supply. A secondary control circuit is coupled to the switched element. The secondary control circuit is to be coupled across an output of the second winding to switch the switched element in response to a difference between an actual output value at the output of the second winding and a desired output value to force a current in a third winding of the energy transfer element that is representative of the difference between the actual output value at the output of the second winding and the desired output value. A primary switch is to be coupled to a first winding of the energy transfer element. A primary control circuit is coupled to the primary switch. The primary control circuit is to be coupled to receive the current forced in the third winding of the energy transfer element in response to the secondary control circuit. The primary control circuit is coupled to switch the primary switch to regulate an output of the power supply coupled to the output of the second winding in response to the forced current.
摘要:
A plurality of DC power supply modules have track pins interconnected for tracking of output voltages of the modules during power-up and normal power-down. Each module pulls down its track pin voltage in response to any fault, and detects a track pin voltage below a threshold to detect a fault communicated from any other module, to facilitate fault power-down. The track pin voltage is initially raised above the threshold for power-up. One module can be designated a master for monitoring an input voltage to the modules and for determining the track pin voltage for normal power-up and power-down.
摘要:
A control unit controls cascaded PFC and LLC converters, the LLC converter having an input coupled to an output, of the PFC converter and providing an output voltage that decreases with increasing switching frequency. The control unit produces a sawtooth waveform with a linear ramp for controlling the LLC converter switching frequency, and hence its output voltage, in dependence upon a feedback signal. It also produces for the PFC converter a PWM signal with a frequency that is the same as or an integer fraction of the LLC converter switching frequency, by comparing two thresholds with the linear ramp in respective different cycles of the sawtooth waveform to turn on and off a switch of the PFC converter during these different cycles. Logic circuits prevent PFC converter switch transitions from occurring simultaneously with switching transitions of the LLC converter.
摘要:
A flyback converter with forced primary regulation is disclosed. An example flyback converter includes a coupled inductor including a first winding, a second winding, and a third winding. The first winding is coupled to an input voltage and the second winding is coupled to an output of the power converter. A switched element is coupled to the second winding. A secondary control circuit is coupled to the switched element and the second winding. The secondary control circuit is coupled to switch the switched element in response to a difference between a desired output value and an actual output value to force a current in the third winding that is representative of the difference between the desired output value and the actual output value. A primary switch is coupled to the first winding. A primary control circuit is coupled to the primary switch and the third winding. The primary control circuit is coupled to switch the primary switch to regulate the output of the power converter in response to the forced current.