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  <xsd:element id="aeis_RevolvingFacilityVariableInterestRateMember" name="RevolvingFacilityVariableInterestRateMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="aeis_TreasuryStockSharesAcquiredRelatedParty" name="TreasuryStockSharesAcquiredRelatedParty" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="aeis_TegamIncMember" name="TegamIncMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="aeis_NorthAmericaExcludingUnitedStatesMember" name="NorthAmericaExcludingUnitedStatesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="aeis_LineOfCreditFacilityContingentIncreaseAdditionalBorrowingCapacity" name="LineOfCreditFacilityContingentIncreaseAdditionalBorrowingCapacity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="aeis_EquityClassifiedAwardsMember" name="EquityClassifiedAwardsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="ComputerEquipmentFurnitureFixturesAndVehiclesMember" id="aeis_ComputerEquipmentFurnitureFixturesAndVehiclesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LiabilityClassifiedAwardsMember" id="aeis_LiabilityClassifiedAwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfActiveStockBasedIncentiveCompensationPlans" id="aeis_NumberOfActiveStockBasedIncentiveCompensationPlans" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SlPowerElectronicsCorporationMember" id="aeis_SlPowerElectronicsCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ScheduleOfLineOfCreditFacilityAvailableCapacityTableTextBlock" id="aeis_ScheduleOfLineOfCreditFacilityAvailableCapacityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
