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Namen diplomske naloge je predstaviti toplotne črpalke in njihov vpliv na kakovost električne napetosti v omrežju. Odjemalci v današnjem času uporabljamo ogromno električnih naprav, kjer mnoge od njih slabšajo napetostne razmere v omrežju. Večkrat je mentor praktičnega izobraževanja v podjetju Elektro Gorenjska, d.d. pri reševanju problemov zaradi slabih napetostnih razmer naletel na odjemalce, ki so kot toplotni vir uporabljali toplotne postaje. Na njegovo priporočilo sem izbral toplotne črpalke, ki so zadnje čase močno v porastu. Na konkretnem primeru sem prikazal napetostno stanje odjemalca, ki za ogrevanje hiše uporablja toplotno postajo in se je zaradi težav s kakovostjo napetosti pritožil distribucijskemu podjetju. S to diplomsko nalogo bi rad poudaril, da za slabe napetostne razmere ni mogoče kazati s prstom le na enega krivca. To je težava, v katero so vključeni tako proizvajalci električnih naprav, odjemalci kot tudi distribucijska podjetja. Slednja so kot dobavitelj električne energije seveda dolžna vzpostaviti ustrezne napetostne razmere, vendar pa so zaradi nevednih in nerazumevajočih odjemalcev večkrat kritizirani kot edini krivec. V začetku diplomskega dela sem na kratko predstavil kakovost oskrbe z električno energijo, ki je temelj za zanesljivo delovanje strojev in za minimaliziranje njihovih izgub, za preprečitev okvare opreme in naprav ter za končno zadovoljstvo uporabnikov. Kakovost oskrbe z električno energijo je nadpomenka kakovosti napetosti v omrežju. Kakovost napetosti sloni na poznavanju kratkostične moči in na elektromagnetni združljivosti, določena pa je s standardom SIST EN 50160. Podvržena je tokovnim in elektromagnetnim motnjam, ki napetost popačijo ter poslabšajo delovanje naprav in opreme. Opisal sem vseh trinajst elektromagnetnih motenj, vendar me v povezavi s toplotnimi črpalkami zanimajo le napetostni upadi in hitre napetostne spremembe. V drugem delu naloge sem se površno dotaknil distribucijskega omrežja, ki je zadnji segment v verigi omrežja, od vira energije do odjemalca. Za zagotavljanje napetosti in frekvence v skladu s standardi mora biti omrežje dobro načrtovano. Velikokrat je ravno neustrezen presek vodnikov kriv za nedopustno velike tokovne obremenitve in za prevelike padce napetosti. Pri načrtovanju so pomembne tudi dolžine vodnikov med uporabniki, oddaljenost med virom in odjemalcem ter faktor istočasnosti. Izpeljal sem tudi enačbo za izračun padca napetosti na vodu z dolžino l. Tretji del diplomske naloge opisuje toplotne črpalke, ki so zadnje čase kot način ogrevanja zelo v porastu. Predstavljajo obnovljivi vir energije, saj črpajo sončno energijo akumulirano v snoveh. Opisal sem splošno delovanje tokokroga toplotnih naprav, njene temeljne enote ter različne vrste glede na princip delovanja. Pri svojem raziskovanju sem se usmeril v toplotne črpalke zrak/voda, kjer se izkorišča toploto akumulirano v zraku in se jo prenese na vodo. Podrobneje sem se posvetil tudi električnim elementom znotraj toplotne črpalke. Kompresor je zanimiv zlasti iz vidika zagonov in njegove glasnosti, električno krmiljenje in regulacija ter električni grelec pa iz vidika povečanja porabe električne energije. V četrtem delu naloge sem poudaril razloge za nastanek težav v relaciji toplotnih črpalk in elektroenergetskega omrežja. Težave toplotnih črpalk nastanejo zaradi preobčutljivosti na elektromagnetne motnje ali morebitnih velikih zagonskih tokov, težave v omrežju pa vzrok starosti ali slabega načrtovanja. V zadnjem delu diplomske naloge sem teoretični del nadgradil s konkretnim primerom slabih napetostnih razmer. Odjemalec uporablja kakovostno toplotno črpalko z mehkim zagonom, vzrok za težave pa se nahaja v omrežju s premajhnimi preseki. The aim of this thesis is to present heat pumps and their impact on the quality of the electricity supply network. Customers today use a lot of electrical appliances, where many of them deteriorating voltage conditions on the network. Several times the mentor of practical education in the company Elektro Gorenjska, d.d. in solving problems due to poor voltage conditions encountered clients who are used as the heat source of the heat station. On his recommendation I chose the heat pump, which recently strongly on the rise. A specific example I show the stress state of the client, which is used for heating houses heat station and is due to problems with the quality of the voltage appealed to the distribution company. This thesis would like to emphasize that the poor power situation can not show the finger at only one culprit. This is a problem which includes both manufacturers of electrical appliances, customers as well as distribution companies. The latter as a supplier of electricity, of course, required to establish the appropriate voltage conditions, but because of the ignorant and unsupportive customers repeatedly criticized as the only culprit. At the beginning of the thesis, I briefly introduced the quality of electricity supply, which is the basis for the reliable operation of the machines and to minimize their losses, to prevent damage to the equipment and appliances, and for end user satisfaction. The quality of the power supply is superior voltage quality in the network. The voltage quality is based on knowledge of the short-circuit power and electromagnetic compatibility and determined by the SIST EN 50160 standard and is subject to the current electromagnetic disturbances that distort the voltage and impair the operation of plant and equipment. I described all thirteen of electromagnetic interference, but I'm in conjunction with heat pumps only interested voltage sags and rapid voltage changes. In the second part of the thesis I carelessly touched the distribution network, which is the last segment in the chain network, the power source to the customer. To ensure voltage and frequency in accordance with the standards must be well-planned network. It is often very inadequate conductor cross section to blame for the unacceptable high current load and excessive voltage drops. When planning are also important as the cable length between the users, the distance between the source and the customers as well as simultaneous factor. I also carried out the equation for calculating the voltage drop on the line with a length l. The third part of the thesis describes a heat pump, which recently as a method of heating is on the rise. A source of renewable energy, as extracting solar energy accumulated in substances. I described the general operation of the circuit thermal plants, its basic unit and different types according to the principle of operation. In my research I have focused on the heat pump air / water, which exploits the heat accumulated in the air and transfer it to the water. More information I dedicated the electric element inside the heat pump. The compressor is particularly interesting from the perspective starts and its volume electric control and regulation, and an electric heater but from the point of view of the increase in electricity consumption. In the fourth part of the thesis I pointed out the reasons for the emergence of problems in between the heat pump and the electricity grid. Problems of heat pumps caused by hypersensitivity to electromagnetic interference or any large initial currents problems in the network but the cause of old age or poor planning. In the last part of the thesis I theoretical part with concrete examples of bad voltage conditions. The client uses good quality heat pump with soft start, the cause of the problem is located in the network with insufficient sections.