# Analysis of Plasma Reactor Interaction with the Power Grid Depending on the Power Supply Design
## 3 Electrical Power Supply System  
The most important device cooperating with the plasma reactor is the power supply system. Properly selected, it guarantees stable parameters of the generated plasma, high efficiency of the plasma process and low interference generated by the plasma reactor. There are many plasma reactor power supply solutions dedicated to specific equipment or processes. The cooperation of the GlidArc plasma reactor was analysed with four different power supply systems. The power supplies under study were created in the Department of Electrical Engineering and Electrotechnologies at Lublin University of Technology for research projects on plasma applications in technology and industry. This research focused on the possibilities of using plasma generated in GlidArc-type reactors. However, there was no detailed analysis of the cooperation of this type of reactor with power supply systems. The basic element of all the power supplies discussed is the transformer. Sometimes the transformer itself, when properly designed, makes a good power supply. Such a power supply is shown in Figure 2. The power supply design uses three single-phase transformers T\({}_{1}\), T\({}_{2}\) and T\({}_{3}\) connected in a YNy three-phase connection circuit. These transformers form the T-circuit supplying the working electrodes WE\({}_{1}\), WE\({}_{2}\) and WE\({}_{3}\) of the plasma reactor. The transformers are characterised by cores made of the amorphous material Metglas 2605 SA1. The primary and secondary windings are concentrically wound in a manner typical of most transformers. A separate electrical circuit IS is used to power the IE\({}_{1}\) and IE\({}_{2}\) ignition electrodes of the plasma reactor. This circuit uses a high-frequency electronic high-voltage inverter. The parameters of the power supply circuit are given in Table 2. The letter designation TPS is adopted for this power supply. An extension of the TPS power supply system is the system labelled PCS. In the PCS power supply system, transformers T\({}_{1}\), T\({}_{2}\) and T\({}_{3}\) are supplied by an AC/DC/AC transistor converter, as shown in Figure 3. The converter allows the frequency of the reactor supply voltage to be adjusted between 10 and 200 Hz, and the reactor discharge current to be adjusted. Chokes with an inductance of 20 mH are installed between the transformers and the converter. The next power supply system to be tested was a system called ITPS, consisting of three suitably connected single-phase transformers, as shown in Figure 4. Three identical transformers T\({}_{1}\), T\({}_{2}\) and T\({}_{3}\) were connected to form a three-phase connection system YNyn. These transformers form the power circuit for the working electrodes WE\({}_{1}\), WE\({}_{2}\) and WE \begin{table}
\begin{tabular}{l l l l l} \hline
**Power Supply Type** & **TPS** & **ITPS** & **IFCTPS** & **PCS** \\ \hline Power & 13.8 kVA & 9 kVA & 11 kVA & 13.8 kVA \\ \hline Supply voltage & 230 V & 230 V & 230 V & 230 V \\ \hline Supply current & 20 A & 20 A & 16 A & 20 A \\ \hline Output voltage & 1.2 kV & 1.3 kV & 1.2 kV & 1.2 kV \\ \hline Output current & 3 A & 5 A & 2.4 A & 3 A \\ \hline Output frequency & 50 Hz & 50 Hz & 50 Hz & 10 \(\div\) 200 Hz \\ \hline \end{tabular}
\end{table} 
Table 2: Parameters of the reactor working electrode supply circuits. Figure 3: Converter power system PCS, PR—plasma reactor, T—reactor working electrodes power circuit, IS—ignition electrodes power circuit, C—chokes, IC—AC/DC/AC transistor converter, Np\({}_{1}\), Np\({}_{2}\), Np\({}_{3}\)—primary windings, Np\({}_{1}\), N\({}_{2}\), N\({}_{3}\)—secondary windings, WE\({}_{1}\), WE\({}_{2}\), WE\({}_{3}\)—plasma reactor working electrodes, IE\({}_{1}\), IE\({}_{2}\)—reactor ignition electrodes.