Description:FIELD OF INVENTION
High Voltage DC Generation using AC Rectification and Voltage Multiplication
Department: Electrical and Electronics Engineering, specializing in Power Electronics and High Voltage Engineering
BACKGROUND OF INVENTION
In high-voltage applications, the need for efficient and compact DC power sources is paramount. Traditional methods of generating high-voltage DC require bulky transformers and complex circuitry, which pose challenges in terms of cost, space, and energy efficiency. The invention of a high-voltage DC generation system using diodes and capacitors in a voltage multiplier circuit provides a practical and effective alternative. This technique, widely known as the Cockcroft-Walton or Villard voltage multiplier, enables the conversion of standard AC supply into a stable high-voltage DC output, reaching up to 2 kV. By strategically cascading multiple diode-capacitor stages, the circuit successively steps up the voltage while maintaining a lightweight and compact design. This innovation is instrumental in applications such as X-ray machines, particle accelerators, industrial electrostatics, and scientific instrumentation. It enhances efficiency, reliability, and safety while eliminating the need for costly transformers, making high-voltage generation more accessible for modern technological advancements.
the patent application number 202241026863 discloses a high step-up dc-dc converter with switched inductor, switched capacitor and voltage multiplier cell. a high step-up dc-dc converter integrating switched inductor, switched capacitor, and voltage multiplier cell enhances voltage gain efficiently, making it ideal for renewable energy systems, electric vehicles, and high-voltage applications.
the patent application number 202141027429 discloses a tool holder for a torque multiplier assembly and method of assembly thereof. a tool holder for a torque multiplier assembly securely accommodates torque tools, ensuring precise force transmission. the method of assembly involves aligning, fastening, and integrating components for enhanced durability, efficiency, and mechanical stability.
SUMMARY
The invention presents a highly efficient method for generating high-voltage DC up to 2 kV from an AC source using a diode-capacitor-based voltage multiplier circuit. By employing a carefully designed multi-stage configuration, this system progressively steps up the AC voltage through successive rectification and charge storage, eliminating the need for bulky transformers. The architecture of the circuit is optimized to ensure minimal power loss, enhanced reliability, and compactness, making it suitable for various high-voltage applications such as medical equipment, industrial electrostatics, scientific research, and power transmission. The use of diodes and capacitors in a cascading manner allows the generation of stable, ripple-free high-voltage DC with high efficiency. This invention significantly improves upon traditional high-voltage power supply methods, offering a lightweight, cost-effective, and easily implementable solution for modern high-voltage applications while maintaining superior electrical performance.
Objective of the Invention
1. To develop an efficient and compact high-voltage DC generation system using diode-capacitor voltage multiplication.
2. To eliminate the need for bulky transformers, reducing size, weight, and cost.
3. To achieve a stable and ripple-free high-voltage DC output suitable for industrial, medical, and scientific applications.
4. To enhance the reliability and efficiency of high-voltage power supply systems.
5. To provide a scalable and modular design adaptable to various voltage requirements.
DETAILED DESCRIPTION OF INVENTION
The generation of high-voltage DC (HVDC) up to 2 kV from a standard AC supply is crucial for various applications, including industrial, medical, and scientific fields. Traditional methods of voltage stepping utilize step-up transformers, which increase voltage by electromagnetic induction. However, these transformers are often bulky, expensive, and inefficient for low-current applications.
To overcome these limitations, the voltage multiplier circuit, composed of diodes and capacitors in a ladder network, provides a compact and efficient solution for converting AC to high-voltage DC. This approach is particularly useful where high voltage with low current is required, such as in CRT displays, oscilloscopes, X-ray machines, and industrial electrostatic applications.
1. Compact and lightweight – Eliminates the need for large transformers.
2. Efficient AC-to-DC conversion – Suitable for applications requiring high voltage and low current.
3. Cost-effective – Uses inexpensive diodes and capacitors.
4. Scalable design – Output voltage can be increased by adding more stages.
5. Reliable and maintenance-free – No moving parts, reducing wear and tear.
Existing Methods for High-Voltage DC Generation
1. Step-Up Transformers with Rectifiers
o Uses transformers to increase AC voltage, followed by rectifiers to convert it to DC.
o Disadvantages: Bulky, costly, and less efficient for low-current applications.
2. Marx Generator
o Generates pulsed high-voltage DC using a series of capacitors and spark gaps.
o Disadvantages: Not suitable for continuous DC output applications.
3. Cockcroft-Walton Voltage Multiplier
o Uses a ladder network of diodes and capacitors to progressively step up AC voltage.
o Advantages: Compact, scalable, and efficient for generating HVDC from an AC source.
The voltage multiplier circuit provides a reliable, efficient, and cost-effective method for generating high-voltage DC up to 2 kV from a 230V AC source. This makes it an ideal alternative to transformers, especially for applications requiring high voltage and low current.

Figure 1: Block diagram
This block diagram represents a High Voltage DC Generation System (up to 2 kV) using a Voltage Multiplier Circuit. Below is a detailed explanation of each block:
1. Supply (AC Source)
The system begins with a standard 230V AC supply, which provides the necessary input voltage for the multiplier circuit.
2. Series Lamp
A series lamp is connected in line with the AC supply to serve as a protective component. It acts as an indicator and current limiter, preventing excessive current flow and protecting the circuit components. If a fault occurs, the lamp brightness increases, signaling a possible issue.
3. Diode and Capacitors in Ladder Networks
This is the core of the voltage multiplier circuit, consisting of diodes and capacitors arranged in a ladder configuration. It progressively steps up the AC voltage while converting it into DC. The Cockcroft-Walton multiplier is commonly used in this stage, where each stage effectively doubles the voltage.
4. Voltage Doubler Circuit
This block functions as the first stage of voltage multiplication, where the input AC voltage is rectified and stored in capacitors, leading to a doubling of the peak voltage. This circuit ensures an efficient boost in the voltage while maintaining stability.
5. Cascade Circuit
The cascade circuit consists of additional diode-capacitor stages that further multiply the voltage. By adding more stages, the system increases the DC voltage step-by-step, ultimately achieving the desired 2 kV output.
6. 2 kV DC Output
The final high-voltage DC output is generated at this stage, reaching up to 2 kV. This high voltage can be utilized for various applications, including medical devices, industrial electrostatic applications, and testing equipment.
7. Potential Divider (10:1 Ratio)
Since standard multimeters cannot directly measure high voltages like 2 kV, a potential divider circuit is used. It scales down the high voltage in a 10:1 ratio, allowing safe measurement. For instance, a 200V reading on the multimeter corresponds to an actual output of 2 kV.

8. Low Voltage DC for Meter Reading
The potential divider provides a low-voltage DC equivalent of the high voltage, making it accessible for measurement. This ensures accurate and safe monitoring of the high-voltage output.
Working Principle
1. The AC supply powers the circuit, with a series lamp acting as a safety mechanism.
2. The diode-capacitor ladder network converts AC into progressively higher DC voltage.
3. The voltage doubler circuit boosts the voltage in the initial stage.
4. The cascade circuit further steps up the voltage using multiple stages.
5. The final DC output reaches up to 2 kV.
6. A potential divider (10:1) enables safe voltage measurement by stepping down the voltage proportionally.
This system effectively generates high-voltage DC up to 2 kV using a compact, transformerless voltage multiplier approach, making it highly useful for applications requiring high voltage and low current. The inclusion of a series lamp for protection and a potential divider for safe voltage measurement ensures efficiency, reliability, and safety.

Figure 2: Schematic diagram
Hardware Components
1. Resistors – Used to limit current, divide voltage, and provide stability in the circuit.
2. Capacitors – Store and release electrical energy, essential for voltage multiplication and filtering.
3. Diodes – Allow current to flow in one direction, preventing reverse current and enabling rectification in the voltage multiplier circuit.
4. 1N4007 Diode – A general-purpose rectifier diode with a high voltage rating of 1000V and a current capacity of 1A. It is commonly used in power rectification circuits, including voltage multipliers, due to its ability to handle high reverse voltage and moderate current.
This project is designed to generate high-voltage DC up to 2.5kV from a standard 230V AC supply using a multistage voltage multiplier circuit composed of diodes and capacitors. The circuit operates on the principle of voltage multiplication, where multiple capacitor-diode stages incrementally step up the rectified voltage.
1. Voltage Multiplication Process:
o The circuit uses 8 stages of voltage multiplication, with silicon diodes (D1-D8) and 16 electrolytic capacitors (100µF/400V each) arranged in a ladder network.
o The input AC voltage (230V RMS) is first rectified and then multiplied in successive stages.
o The output voltage is given by
o
2. Voltage Measurement Using Potential Divider:
o Since standard multimeters cannot directly measure high voltage, a potential divider is introduced.
o The divider consists of 10 resistors in series, ensuring that the voltage across each resistor is: 2.5kV/10=250V
o This makes it easier to measure using a standard meter.
3. Multimeter Reading Consideration:
o Low-cost digital multimeters generally have an input impedance of 1MΩ, causing them to display only half the actual voltage due to resistance loading effects.
o Therefore, a 125V reading on the multimeter corresponds to the actual 2.5kV output.
o High-end multimeters with 100MΩ input impedance provide accurate readings since their effect on circuit impedance is negligible.
4. Safety Considerations:
o High voltage storage: Capacitors retain charge even after power is disconnected, posing a shock risk.
o Discharge Resistors: To counter this, 500kΩ resistors are placed across capacitor pairs to automatically discharge stored energy, ensuring safe operation.
• A step-up transformer could also increase voltage, but it would be bulky, expensive, and inefficient for low-current applications.
• A voltage multiplier is compact, lightweight, and cost-effective, making it suitable for generating high voltage at low current, as needed in applications like:
o CRTs (Cathode Ray Tubes)
o TV Picture Tubes
o Oscilloscopes
o Industrial and medical high-voltage systems
This project effectively demonstrates the use of diodes and capacitors in a voltage multiplier circuit to step up 230V AC to around 2.5kV DC safely and efficiently. With proper voltage measurement techniques and safety precautions, the design can be extended to higher voltage levels (30-50kV) for advanced industrial and medical applications.
•
Figure 3: Layout Diagram
Testing Procedures for Circuit Verification
To ensure the proper functioning of an electronic circuit, various tests must be conducted after hardware assembly and soldering. The following are two crucial tests:
1. Continuity Test
A continuity test is used to verify whether an electrical circuit is complete, allowing current to flow without interruption. This is particularly important to detect open circuits caused by broken conductors, damaged components, or excessive resistance.
Procedure:
• A small voltage is applied across the circuit using a continuity tester or a multimeter in buzzer mode.
• If the circuit is complete, current flows, and the tester produces a beep sound or an LED lights up.
• If there is a break in the circuit, no sound or light is observed, indicating an open path in the circuit.
Applications:
• Identifying breaks in a bundle of wires by checking for negligible resistance between the correct ends.
• Detecting improper soldering, component failures, or circuit diagram errors.
Implementation in This Project:
• This test is performed immediately after soldering to ensure all connections are intact.
• The multimeter’s ground terminal is connected to the circuit’s ground, and the other probe is placed on the path being tested.
• If the circuit is continuous, the multimeter beeps, confirming a complete connection.
2. Power-On Test
The power-on test ensures that the voltage at various terminals is as required before inserting integrated circuits (ICs). This helps prevent damage to components due to incorrect voltage levels.
Procedure:
1. Check Power Source:
o If using a transformer, measure the output voltage to confirm the expected 12V AC (or as per the circuit design).
o If using a battery, verify its voltage level to ensure it is fully charged.
2. Verify Power Supply Circuit:
o Before powering the circuit, ensure that ICs are not yet inserted to avoid damage.
o Measure the voltage at the input of the voltage regulator (e.g., 7805, 7809, 7815, 7915, etc.).
o Check if the regulator provides the correct output voltage:
 7805 → 5V output
 7809 → 9V output
 7815 → 15V output
3. Measure Voltage at Critical Terminals:
o Using a multimeter in voltage mode, verify the power supply pins of the ICs and other circuit terminals.
o Ensure each component receives the required voltage as per the design.
Outcome:
If all voltage levels are correct, the circuit is ready for further testing and IC integration. This step prevents damage to sensitive components and ensures stable operation.

DETAILED DESCRIPTION OF DIAGRAM
Figure 1: Block diagram
Figure 2: Schematic diagram
Figure 3: Layout Diagram , Claims:1. High voltage dc upto 2 kv from ac by using diode and capacitor in voltage multiplier circuit claims that the circuit utilizes a multi-stage voltage multiplier configuration using diodes and capacitors to convert an AC input (230V RMS) to a high-voltage DC output (approximately 2.5KV).
2. Use of Silicon Diodes and Electrolytic Capacitors: The design incorporates eight silicon diodes (D1–D8) and sixteen 100µF/400V electrolytic capacitors arranged in a multi-stage configuration to achieve the required voltage boost.
3. Stage-Wise Voltage Doubling: Each stage in the voltage multiplier doubles the peak AC voltage and stores the charge, progressively increasing the output voltage up to the desired high-voltage level.
4. Approximate Output Calculation: The output voltage is estimated using the formula:
V_out ≈ √2 × V_in × Number of Stages
With 230V AC input and 8 stages, the output reaches approximately 2.5KV DC.
5. Potential Divider for Voltage Measurement: A series resistor potential divider (consisting of 10 resistors) is used to scale down the high voltage for safe measurement, making it possible to read a proportional voltage on a standard multimeter.
6. Multimeter Impedance Consideration: Due to the low input impedance (~1MΩ) of standard multimeters, the measured voltage appears half of the actual value (e.g., a reading of 125V corresponds to 2.5KV). High-impedance multimeters (100MΩ) would show the correct value.
7. Automatic Capacitor Discharge Mechanism: 500KΩ resistors are connected across each capacitor pair to ensure automatic discharge after circuit use, preventing high-voltage retention and reducing the risk of electric shock.
8. High Voltage Rectification with Diodes: The 1N4007 diodes are used for rectification, enabling high-voltage AC-to-DC conversion while blocking reverse current to maintain voltage stability in each stage.
9. Safety Precautions for High Voltage Handling: The design includes resistors across capacitors to prevent accidental shocks and ensures controlled voltage scaling, making it safer for practical applications.
10. Scalability for Higher Voltages: The number of stages can be increased or decreased based on voltage requirements, making the circuit flexible for applications requiring different high-voltage outputs.