Controller of Solar charger Circuit Diagram

 This is the simple Controller of Solar charger Circuit Diagram .When connecting a solar panel to a rechargeable battery, it is usually necessary to use a charge controller circuit to prevent the battery from overcharging. Charge control can be performed with a number of different circuit types. Lower power solar systems can use a series analog charge controller. Series regulators control the charging current by interrupting the flow of current from the solar panel to the battery when the battery reaches a preset full voltage. MPPT controllers use an inductor for energy storage and a high frequency switching circuit to transfer the energy to the battery.

This circuit is for a shunt-mode charge controller. In a shunt-mode circuit, the solar panel is permanently connected to the battery via a series diode. When the solar panel charges the battery up to the desired full voltage, the shunt circuit connects a resistive load across the battery to absorb the excess power from the solar panel. The main advantage of shunt-mode solar regulation is the lack of a switching transistor in the power path between the solar panel and battery. Switching transistors are non-perfect devices, they waste a percentage of available solar power as heat. Inefficiency in the shunt-mode controller’s switching transistor does not effect charging efficiency, it only turns on when excess power is purposely being wasted.

Controller of Solar charger Circuit Diagram 

Solar power is routed from the PV panel through the 1N5818 Schottky diode to the battery. When the battery reaches the full setpoint, the output on the lower half of the TLC2272 dual op-amp turns on. This activates the IRFD110 MOSFET transistor and connects the 68 ohm 3W load resistor to the battery. The load across the battery causes the battery voltage to drop, and the comparator circuit turns back off. This oscillation continues while solar power is available. The 300nF capacitor across the op-amp slows the oscillation frequency down to a few hertz. The two 100K resistors in series provide a regulated 4.5V reference point for use as comparator reference points.

The 2N3906 transistor is wired with a zener diode in its base circuit, when the PV voltage is above 12V, the 2N3906 transistor turns on and enables the comparator circuit. The upper half of the TLC2272 op-amp inverts the dump load control signal, this is used to power the high intensity red LED. The LED turns on when the battery reaches the full setpoint. The LED does not waste any useful charging power since it only turns on when the battery is full.

The 78L09 IC provides 9V regulated power to the comparator circuitry. Operational power for this circuit is provided entirely from the PV panel, there is virtually no power taken from the battery at night.

This circuit can be modified for higher amperage by replacing the 1N5818 diode, 68 ohm load resistor and IRFD110 MOSFET with higher power components. If the load resistor is connected directly across the PV panel at noon on a sunny day, the PV output voltage should drop to 12V or less. Higher power PV panels will require a resistor with lower ohms and a higher wattage rating. In cold climates, it may be useful to use the load resistor’s heat to keep the battery warm.

Operation of a high power version of this circuit with a wind generator should be possible, although the author has not tried this. For a 20 amp version of this circuit, the IRFD110 MOSFET should be replaced with an IRFZ44N and the 1N5818 schottky diode should be replaced with a 20L15T. Both of these parts should have large heat sinks. The 68 ohm/3W resistor should be changed to a much larger resistor, An 0.6 ohm/250W resistor would be able to handle 20 amps at 12V.

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Simple Bootstrap Circuit Diagram

This is the Simple Bootstrap Circuit Diagram. Bootstrapping the substrate of a JFET amplifier reduces the distortion caused by the non-linlearity of the JFET input capacitance. In the figure, a second feedback divider bootstraps the substrate of Ul. With R{ = 500 kQ (source impedance), THD at 10 kHz was reduced an order of magnitude.

Simple Bootstrap Circuit Diagram

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Simple Train And Slot-Car Controller Circuit Diagram

This is a Simple Train And Slot-Car Controller Circuit Diagram. As shown, a 555 timer (Ul) is configured as an astable multivibrator (oscillator) with a 400:1 duty cycle and a frequency of 40 Hz. When power is applied to the circuit, capacitor CI (connected to pin 6 of Ul) is discharged and the output of the 555 (which is used to sink current) is low. Capacitor CI begins to charge via R1 and R2 toward the positive supply rail. When the charge on CI reaches about 66% of + V, the output of Ul at pin 3 goes high. At that point, CI begins to discharge through R2. 

 Train And Slot-Car Controller Circuit Diagram

When the charge on CI decreases to about 33% of the supply voltage, the output of Ul returns to the low state, and the cycle is repeated until power is removed from the circuit. When the output of Ul is low, C3 is discharged into Ul via transistor Q2. When Ul pin 3 goes high, C3 charges through a current source that consists of Dl, D2, R3, R4, and Ql. The charge/discharge cycling of C3 produces a stream of pulses that are fed to the inverting inputs of U2A and U2B (an LM358 dual op amp). Two voltage-divider networks (R7, R8, R9, and RIO, Rll, R12) set the reference voltage that is applied to the noninverting inputs of U1A and U1B at pins 3 and 5. Potentiometers R9 and R12 set the low-level duty cycle (5 to 10%) of U1A and U1B. 

They are adjusted so that the train headlights glow, but the motor hums only slightly. Potentiometer R3 adjusts the ramp rate of C3 for 100% duty cycle at the full throttle setting. A double-pole, single-throw switch (SIA and SIB) is used to place R3/C4 and R4/C5 in the circuit. The R5/C4 and R6/C5 combinations cause the reference voltages presented to the noninverting inputs to U2A and U2B to change very slowly when the throttle is turned up and down. When the ACL/DCL switch is turned off, the resistance of the throttle-divider networks are much smaller than those of R5 and R6, so the reference voltages on C4/C5 change `instantly` to the new throttle setting. 

The output drivers consist of resistors R13 and R15, and transistors Q3 and Q4 for output` `; and resistors R17 to R20, and transistors Q5 and Q6 for output `B.` Components R13/R16/Q3 and R17/R20/Q5 limit the output drive currents of Q4 and Q6 to about 3 A each. Resistors R14/R15 and R18/R19 turn on Q4 and Q5, respectively, before the breaKOhmver voltage is reached to prevent damage to the output drivers and dissipate the energy that is stored in an inductive field (such as in a motor). The power supply delivers 18 V to the track, ltage regulator U3 (a 78L09 9-V, 100-mA voltage regulator) supplies power to the control circuits

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Audio Powered Tape Recorder Controller Circuit Diagram

This is a simple Audio Powered Tape Recorder Controller Circuit Diagram. A tape recorder can be controlled by rectifying the audio input and driving an IRF511 power MOSFET to switch a tape recorder on when audio is present. This circuit was used with a communications receiver to record intermittent transmissions (such as aircraft, repeater output, etc.). 

 Audio Powered Tape Recorder Controller Circuit Diagram

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Simple Universal Power Controller Circuit Diagram

This is a simple universal power controller circuit diagram. In this circuit use Relay K1 has a low-impedance coil and K2 has a high-impedance coil. When a sensor opens, current is routed through the coil of Kl. K1 activates, opens its contacts, and prevents a sensor contact re closure from affecting the circuit. When Kl contacts open, current to the main relay K2 is limited by the impedance of Kl. 2 controls power to a load (air conditioner, furnace blower, etc.).

Universal Power Controller Circuit Diagram

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Build a Bang-Bang Controllers Circuits Diagram

Bang-Bang Controllers Circuits Diagram Just one chip, the PWR-DRV1 from Power Integrations, builds a `bang-bang` controller that switches 275 mA and runs off the rectified 115-Vac mains. An on-chip zener diode powers the chip from high voltage through a dropping resistor.


Bang-Bang Controllers Circuits Diagram

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