UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 1)* American Superconductor Corporation ----------------------------------- (Name of Issuer) Common Stock, $.01 par value ---------------------------- (Title of Class of Securities) 030111108 --------- (CUSIP Number) George W. Lloyd, Esq. Testa, Hurwitz & Thibeault, LLP High Street Tower 125 High Street Boston, MA 02110 ----------------- (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) September 29, 1999 ------------------ (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(b)(3) or (4), check the following box [_]. Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See (S)240.13d-7 for other parties to whom copies are to be sent. *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page. The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D - ----------------------- --------------------- CUSIP NO. 030111108 PAGE 2 OF 6 PAGES - ----------------------- --------------------- - ------------------------------------------------------------------------------ NAME OF REPORTING PERSON 1 S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON CHARTH (Compagnie Holding d'Applications et de Realisations Thermiques et Hydraliques) S.A. - ------------------------------------------------------------------------------ CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* 2 (a) [_] (b) [_] - ------------------------------------------------------------------------------ SEC USE ONLY 3 - ------------------------------------------------------------------------------ SOURCE OF FUNDS* 4 WC - ------------------------------------------------------------------------------ CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [_] 5 - ------------------------------------------------------------------------------ CITIZENSHIP OR PLACE OF ORGANIZATION 6 France - ------------------------------------------------------------------------------ SOLE VOTING POWER 7 NUMBER OF -0- SHARES ----------------------------------------------------------- SHARED VOTING POWER BENEFICIALLY 8 -0- OWNED BY ----------------------------------------------------------- EACH SOLE DISPOSITIVE POWER 9 REPORTING -0- PERSON ----------------------------------------------------------- SHARED DISPOSITIVE POWER WITH 10 -0- - ------------------------------------------------------------------------------ AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 11 -0- - ------------------------------------------------------------------------------ CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* 12 [_] - ------------------------------------------------------------------------------ PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 13 0% - ------------------------------------------------------------------------------ TYPE OF REPORTING PERSON* 14 CO - ------------------------------------------------------------------------------ *SEE INSTRUCTIONS BEFORE FILLING OUT! INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7 (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.

SCHEDULE 13D - ----------------------- --------------------- CUSIP NO. 030111108 PAGE 3 OF 6 PAGES - ----------------------- --------------------- This statement on Schedule 13D Amendment No. 1 ("Amendment No. 1") is an amendment to the Schedule 13D (filed on October 16, 1997) that was filed with the Securities and Exchange Commission on behalf of CHARTH (Compagnie Holding D'Applications et De Realisations Thermiques et Hydraliques) S.A., a corporation organized under the laws of France ("CHARTH"). CHARTH is a wholly-owned subsidiary of Electricite de France, S.A., a corporation organized under the laws of France ("EDF"). Item 5. Interest in Securities of the Issuer On September 28, 1999, CHARTH transferred 1,000,000 shares of Issuer's Common Stock to E.D.F. Capital Investissement, S.A., a wholly-owned subsidiary of EDF, for no consideration. (a) Amount Beneficially Owned: CHARTH beneficially owns 0 shares of Common Stock of the Issuer. Percent of Class: Based on shares outstanding as of June 30, 1999, CHARTH owns 0% of the outstanding Common Stock of the Issuer. (b) Number of shares as to which CHARTH has: (i) sole power to vote or direct the vote: 0 shares (ii) shared power to vote or direct the vote: Not applicable. (iii) sole power to dispose or to direct the disposition of: 0 shares (iv) shared power to dispose or to direct the disposition of: Not applicable. (c) Except as set forth in this Amendment No. 1, none of CHARTH, EDF, and, to the best knowledge of CHARTH and EDF, any person named in Schedules I and II, has affected any transaction in the Common Stock during the past 60 days. (d) Not applicable. (e) On September 28, 1999, CHARTH ceased to be the beneficial owner of more than five percent of the Issuer's Common Stock.

SCHEDULE 13D - ----------------------- --------------------- CUSIP NO. 030111108 PAGE 4 OF 6 PAGES - ----------------------- --------------------- After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and current. Date: September 16, 1999 CHARTH (COMPAGNIE HOLDING D'APPLICATIONS ET DE REALISATIONS THERMIQUES ET HYDRAULIQUES) S.A. By: /s/ Alain Bertay ----------------- Name: Alain Bertay Title: Chief Executive Officer

SCHEDULE 13D - ----------------------- --------------------- CUSIP NO. 030111108 PAGE 5 OF 6 PAGES - ----------------------- --------------------- SCHEDULE I ---------- Executive Officers and Directors of CHARTH (Compagnie Holding d'Applications et de Realisations Thermiques et Hydraliques) S.A Name and Address of Corporation or Name Principal Occupation or Employment Other Organization in Which Employed - ------------------------------ ---------------------------------- ------------------------------------ Paul Godin Chairman Electricite de France Alain Bertay Chief Executive Officer Electricite de France Pierre Bart Director Electricite de France Jean-Pierre Bourdier Director Electricite de France Loic Caperan Director Electricite de France Pierre Carlier Director Electricite de France Bernard Dupraz Director Electricite de France Bernard Esteve Director Electricite de France Jacques Chauvin Administrator Electricite de France

SCHEDULE 13D - ----------------------- --------------------- CUSIP NO. 030111108 PAGE 6 OF 6 PAGES - ----------------------- --------------------- SCHEDULE II ----------- Conseil D'Administration of Electricite de France, S.A. Name and Address of Corporation or Name Principal Occupation or Employment Other Organization in Which Employed - -------------------------------- ----------------------------------- ------------------------------------ Francois Roussely President Electricite de France Francois Ailleret Administrator Electricite de France Andre Aurengo Administrator Lat Pitie Salpetriere Christophe Blanchard Dignac Administrator Ministere de l'Economie, des Finances et de l'Industrie Jean-Pierre Cremona Administrator Electricite de France Jean-Michel Charpin Administrator Commissariat au Plan Yannick d'Escatha Administrator Commissariat a l'Energie Atomique Daniel Foundoulis Administrator Conseil National de la Consommation Jean Gaubert Administrator Depute Nicolas Jachiet Administrator Ministere de l'Economie, des Finances et de l'Industrie Jean-Marc Mauchaufee Administrator Electricite de France Alain Martin Administrator Electricite de France Yvon Montane Administrator Depute Louis Schweitzer Administrator Renault Robert Pantaloni Administrator Electricite de France Marie-Catherine Polo Administrator Electricite de France Christine Saincy Administrator Electricite de France Jean-Francois Stoll Administrator Ministere de l'Economie, des Finances et de l'Industrie